I1111111111111111 1111111111 11111 111111111111111 IIIII IIIII IIIIII IIII IIII IIII USO 10022679B2 c12) United States Patent (IO) Patent No.: US 10,022,679 B2 Phillip et al. (45) Date of Patent: Jul. 17, 2018
(54) MULTIBLOCK COPOLYMERS AND (52) U.S. Cl. METHODS OF USE CPC ...... BOID 71180 (2013.01); BOID 61102 (2013.01); BOID 6710011 (2013.01); (71) Applicants:University of Notre Dame du Lac, Notre Dame, IN (US); Purdue (Continued) Research Foundation (PRF), West (58) Field of Classification Search Lafayette, IN (US) None See application file for complete search history. (72) Inventors: William A. Phillip, Granger, IN (US); Bryan W. Boudouris, Lafayette, IN (56) References Cited (US) U.S. PATENT DOCUMENTS (73) Assignees: University of Notre Dame du Lac, Notre Dame, IN (US); Purdue 4,828,705 A * 5/1989 Thakore ...... A61K 9/284 Research Foundation, West Lafayette, 210/356 IN (US) 5,098,570 A * 3/1992 Schucker . B0lD 71/54 210/500.37 ( *) Notice: Subject to any disclaimer, the term ofthis (Continued) patent is extended or adjusted under 35 U.S.C. 154(b) by 179 days. FOREIGN PATENT DOCUMENTS
(21) Appl. No.: 14/774,936 CA 2660956 Al 3/2008 CN 1829564 A 9/2006 (22) PCT Filed: Mar. 11, 2014 (Continued)
(86) PCT No.: PCT/US2014/023497 OTHER PUBLICATIONS § 371 (c)(l), Duong, P.H.H., et al., "Planar Biomimetic Aquaporin-incorporated (2) Date: Sep. 11, 2015 Triblock Copolymer Membranes on Porous Alumina Supports for (87) PCT Pub. No.: WO2014/164793 Nanofiltration," J. Membrane Sci.; 409-410:34-43; Aug. 1, 2012. PCT Pub. Date: Oct. 9, 2014 (Continued)
(65) Prior Publication Data Primary Examiner - Krishnan S Menon (74) Attorney, Agent, or Firm - Haukaas Fortius PLLC; US 2016/0023171 Al Jan. 28, 2016 Michael H. Haukaas Related U.S. Application Data (57) ABSTRACT (60) Provisional application No. 61/851,615, filed on Mar. 11, 2013, provisional application No. 61/874,776, The present invention relates to polymer compositions and filed on Sep. 6, 2013. their manufacture. Specifically, the invention relates to mul tiblock polymers and copolymers, their fabrication, modifi (51) Int. Cl. cation and/or functionalization and use as membranes or BOID 71180 (2006.01) films. BOID 67100 (2006.01) (Continued) 18 Claims, 13 Drawing Sheets
C Quenched P, _ a _..I"'\. Self- ;~ - assem~ :::i:-PS-PDMA
--+--HCIO@·•f"'vfl' O~ON
Carboxylicacidfunctionality (dark inner dots) maybe ____/ converted to other,chemistries US 10,022,679 B2 Page 2
(51) Int. Cl. JP 2008272636 A 11/2009 BOID 71128 (2006.01) JP 2009256592 A 11/2009 JP 2012506772 A 3/2012 BOID 71140 (2006.01) RU 2166984 C2 5/2001 BOID 61102 (2006.01) RU 22ll725 C2 9/2003 BOID 69102 (2006.01) RU 2372983 C2 9/2009 C02F 1144 (2006.01) RU 2009ll5200 A 10/2010 WO 2004035180 Al 4/2004 COSF 293/00 (2006.01) WO 2012151482 A2 11/2012 COSJ 9/00 (2006.01) (52) U.S. Cl. OTHER PUBLICATIONS CPC ...... BOID 6710093 (2013.01); BOID 69102 (2013.01); C02F 1144 (2013.01); COSF Extended European Search Report issued by the European Patent 293/005 (2013.01); COSJ 9/00 (2013.01); Office for EP2969155A2 dated Oct. 14, 2016. BOID 67/0016 (2013.01); BOID 71/28 Jung, A., et al., "Formation of integral Asymmetric Membranes of AB Diblock and ABC Triblock Copolymers by Phase Inversion," (2013.01); BOID 71/40 (2013.01); BOID Macromol Rapid Commun.; 34(7):610-615; Apr. 12, 2013. 2325/02 (2013.01); BOID 2325/021 (2013.01); Mastroianni, S.E., et al., "Interfacial Manipulations: Controlling BOID 2325/04 (2013.01); C08J 2353/02 Nanoscale Assembly in Bulk, Thin Film, and Solution Block (2013.01) Copolymer Systems," Langmuir.; 29(12):3864-3878; Mar. 26, 2013. (56) References Cited Savage, D.F., et al., "Architecture and Selectivity in Aguaporins: 2.5 A X-Ray Structure of Aquaporin Z," PLoS Biol.; 1(3):334-340; U.S. PATENT DOCUMENTS Dec. 2003. Stoenescu, R., et al., "Asymmetric ABC-triblock Copolymer Mem 6,458,310 Bl 10/2002 Liu branes Induce a Directed Insertion of Membrane Proteins," 9,527,041 B2 * 12/2016 Wiesner ...... C08J 5/18 Macromol Biosci.; 4(10):930-935; Oct. 20, 2004. 2006/0 ll8482 Al 6/2006 Kloos et al. Dorin, Rachel Mika et al., "Designing Block Copolymer Architec 2009/0173694 Al * 7/2009 Peinemann B0lD 67/00ll tures for Targeted Membrane Performance," polymer 55 (2014) 210/650 347-353. 2012/0025414 Al* 2/2012 Schmidt . B82Y 40/00 Guo, Fengxiao, "Functional Nanoporous Polymers From Block 264/212 Copolymer Precursors," Ph.D. Thesis, Jun. 23, 2010 [online], Department of Chemical and Biochemical Engineering, Technical University of Denmark. FOREIGN PATENT DOCUMENTS Phillip, William A., et al., "Tuning Structure and Properties of Graded Triblock Terpolymer-Based Mesoporous and Hybrid CN 101516481 A 8/2009 Films," ACS Publications, Nano Letters, 20ll, ll, 2892-2900. CN 102203159 A 9/20ll JP S5676408 A 6/1981 Sperschneider, Alexandra et al., "Towards Nanoporous Membranes JP S62193604 A 8/1987 Based on ABC Triblock Terpolymers," Small 2007, 3, No. t, JP 2000033246 A 2/2000 1056-1063. JP 2008189910 A 8/2008 JP 2009533217 A 9/2009 * cited by examiner U.S. Patent Jul. 17, 2018 Sheet 1 of 13 US 10,022,679 B2
Quenched Self- ❖ assem~§ (..... ps"'PDMA
HCl
Carboxylic acid functionality ( dark inner dots) may be converted to other chemistries / (lighter inner dots)
FIG. 1
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FIG. 2 U.S. Patent Jul. 17, 2018 Sheet 2 of 13 US 10,022,679 B2
FIG. 3 PRIOR ART
FIG. 4 PRIOR ART U.S. Patent Jul. 17, 2018 Sheet 3 of 13 US 10,022,679 B2
8 7 6 5 4 3 2 1 0 6 (ppm)
FIG. 5 U.S. Patent Jul. 17, 2018 Sheet 4 of 13 US 10,022,679 B2
16 u ·rn ·rn 20 21 22 23 24 25 26 Elution Volume (ml) -
OD Q1 Q2 0.3 04 OS 0~
1 q (nm· )
FIG. 6
7
6 Parent Bulk Material
--ro 5 0.. ~ 4 m -(/) 3 Deprotected Wetted ,.._.~ Membrane t./) 2
·1
0 0 1.0 2.0 3.0 6.0 8.0 Strain(%)
FIG. 7 U.S. Patent Jul. 17, 2018 Sheet 5 of 13 US 10,022,679 B2
FIG. 8 U.S. Patent Jul. 17, 2018 Sheet 6 of 13 US 10,022,679 B2
FIG. 9 U.S. Patent Jul. 17, 2018 Sheet 7 of 13 US 10,022,679 B2
-40ps\ -35ps1 -3ps\
t10 Tirne {nlinutes)
30 b ·V ' ' . '
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FIG. 10 U.S. Patent Jul. 17, 2018 Sheet 8 of 13 US 10,022,679 B2
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•• 2 4 6 8 10 12 Solution pH
FIG. 11
100
C 0 80 ts Q} 'ijf 60 0:: C -(D 40 0 i... Q) a. 20 II Parent Deprotected II • 0 0 1 2 3 Solute Radius ( nn1)
FIG. 12 U.S. Patent Jul. 17, 2018 Sheet 9 of 13 US 10,022,679 B2
100
C 0 80 ;; 0 .~ a,) a.. 20 II Parent Deprotected II • 0 103 10-i 105 Molecular Weight (Da) FIG. 13 -Heiiurn r __,, -Nitrogen ,,,)_}_/ _ 0.3 -~Argon _r-•'' Cc) 0.. ___[' -1' / <: J-- ___)__ )_,-e:,,,,.:r- 0..---- 0 ..2 ,.__,,,.< r·)~ ,_,f f)---- ___.i---t--" ~ ,..J 0.1 <' t·...~ ,_/ 0 500 1000 1500 Time (seconds) FIG. 14 U.S. Patent Jul. 17, 2018 Sheet 10 of 13 US 10,022,679 B2 FIG. 15 U.S. Patent Jul. 17, 2018 Sheet 11 of 13 US 10,022,679 B2 a 3600 3200 2800 2400 2000 1600 1200 800 1 Wavenumber (cm- ) FIG. 16 U.S. Patent Jul. 17, 2018 Sheet 12 of 13 US 10,022,679 B2 V V r~ 1,lA11 3600 3200 2800 2400 2000 1600 1200 800 1 Wavenumber (cm-' ) FIG. 17 U.S. Patent Jul. 17, 2018 Sheet 13 of 13 US 10,022,679 B2 T PD1\-1A: 105 "C ~ Pi~PS-PDMA Pl-PS ~ 0 Li: r Pl: -ss ❖ c (ti ~, l r(U -100 -50 0 50 100 150 200 Temperature ('0 C) FIG. 18 US 10,022,679 B2 1 2 MULTIBLOCK COPOLYMERS AND tional, thermally-driven separations. Membranes also are METHODS OF USE finding application in the purification of thermally-sensitive molecules. At the same time, the purification of dilute RELATED APPLICATIONS solutes is becoming increasingly important to industry. For 5 example, the separation of monoclonal antibodies and other This application is a National Stage filing under 35 U.S.C. biopharmaceuticals from fermentation broths as well as the § 371 of International Application No. PCT/US2014/ isolation of chemicals derived from naturally-occurring 023497, filed Mar. 11, 2014, which claims priority under 35 resources are emerging areas that rely on robust separation U.S.C. § 119(e) to U.S. Provisional Patent Application No. schemes. However, using traditional separations methods to 61/851,615, filed Mar. 11, 2013, and U.S. Provisional Patent 10 purify these dilute solutes is energy intensive and requires Application No. 61/874,776, filed Sep. 6, 2013, which large volumes of solvents, which tax the natural environ applications are incorporated herein by reference in their ment and inherently increase the cost ofproduction. As such, entirety. the development of membrane processes that can accom- 15 plish these separations in a more environmentally-respon GOVERNMENT SUPPORT sible manner while using less energy is an active area of research. Currently, membranes that would allow chroma This invention was made with government support under DHHS RR025761 awarded the National Institutes ofHealth. tography or extraction based separation processes to be The government has certain rights in the invention. replaced by membrane separations do not exist. 20 As such, generating architectures that have monodisperse FIELD OF THE INVENTION pore sizes and can attain high fluxes, while adding the ability to tailor pore wall chemistry in order to increase fouling The present invention relates to polymer compositions resistance or to perform chemically-selective separations and their manufacture. Specifically, the invention relates to would advance the state-of-the-art in current membrane multiblock polymers and copolymers, their fabrication, 25 technologies. modification and/or functionalization and use as membranes or films. SUMMARY OF THE INVENTION BACKGROUND The present invention provides a novel method for the 30 development and manufacture of new materials, processes, Chemical separations are energy-intensive. About ten and devices for the implementation of membrane separa percent of the daily energy use by humans is consumed to tions, which have been a proven pathway toward more operate these processes. Despite their large energy demand, sustainable chemical separations. chemical separations are essential to the production offood, To this end, the invention described herein embraces a the purification of drinking water, and the development of 35 new paradigm in separations technology that utilizes self therapeutics. As such, a need exists to create energy-efficient assembled, chemically-tunable multiblock copolymers to and environmentally-responsible sustainable materials and fabricate, in a facile and scalable manner, a novel membrane separation processes to produce vital resources that are platform that contains well-defined monodisperse pores with important to sustaining human life on earth. tunable pore chemistries. Because they do not rely on heat to create a separation, 40 In one embodiment, the invention described herein membrane separations avoid the thermodynamic restrictions embraces functional multiblock copolymers useful in the associated with heat use (i.e., the Carnot efficiency). For fabrication ofnano structured, high performance membranes example, the success of seawater desalination by reverse with functional pore walls. osmosis (RO) is a model for the energy savings and sus One aspect of the invention provides a multiblock copo- tainability that can be realized by replacing traditional 45 lymer membrane comprising a nanoporous active selective separation processes with membrane separations. At its layer containing pores having an average diameter of less inception, RO desalination consumed almost three times than 5 nm. more energy than equivalent thermal desalination methods, The exquisite control of the physical and chemical prop such as multistage flash distillation (MSF). However, over erties that can be achieved when practicing aspects of the the past forty years, due to fundamental technological 50 invention improve the properties of the membrane. The advances, the energy demand of seawater RO has fallen precise control of pore size and shape allow for a much dramatically, and it now requires half the energy of MSF. higher flow rate compared to current commercial mem Due to this energy savings, RO is rapidly displacing thermal branes. This also allows for a size-exclusion based mecha methods as the preferred desalination technology. nism where ions, molecules, or other matter in an aqueous Central to the success of RO desalination was the opti- 55 or gaseous medium can be preferentially allowed passage mization ofthe membrane material and membrane structure. through the membrane based on having an effective size that Specifically, the transition from asymmetric cellulose is smaller than the membrane pores or can be preferentially acetate membranes to thin-film composite membranes based disallowed passage through the membrane based on having on polyamide chemistries fueled the success of reverse an effective size that is larger than the membrane pores. The osmosis. Similar opportunities exist for membrane separa- 60 effective size of the ion or molecule may be in reference to tions to replace other energy inefficient and environmentally its ionic size or to its hydration size. When an ion is taxing separations processes, such as chromatography and dissolved in water it forms a hydration shell of loosely extraction. attached water molecules that tends to increase its effective Therefore, it is clear that membrane separations have size (this is known as the hydration size) in terms of its garnered increased attention in recent years because of their 65 transport properties. The chemical functionalization of the ability to bypass the limitations associated with heat use, membrane and/or pores can also be used to further enhance which is an inherent inefficiency that hinders more tradi- membrane selectivity. US 10,022,679 B2 3 4 In some embodiments the membrane is chemically-func PDMA powder. The principle reflection (q*=0.151 nm-1) tionalized to enhance affinity to a specific type of target indicates a solid state domain spacing of -42 nm. The listed matter or contaminant or in other embodiments it may be reflections suggest a hexagonally-packed structure for the designed to mitigate fouling propensity of the membrane. PI-PS-PDMA powder in the solid state. The selectivity of the membrane may be due solely to the 5 FIG. 7. Stress-strain curves of the cast membranes. The pore sizes or to the pore chemistry, or in many embodiments parent bulk material, composed of PI-PS-PDMA, has a to a combination ofthe physical and chemical characteristics toughness of 67 kJ m-3. The parent membrane, has a of the membrane. toughness in the dry state of 2.4 kJ m-3 and 17 kJ m-3 in the wetted state. The functionalized membrane, composed of BRIEF DESCRIPTION OF THE DRAWINGS 10 PI-PS-PAA, had toughness values of 1.7 kJ m-3 and 96 kJ m-3 in the dry and wetted states, respectively. The signifi The following drawings form part ofthe specification and cant increase in toughness of the membranes in the wetted are included to further demonstrate certain embodiments or state may be attributed to the serendipitous feature of various aspects ofthe invention. In some instances, embodi crosslinking of PI domains in the presence of strong acids ments of the invention can be best understood by referring 15 for prolonged periods at elevated temperatures while con to the accompanying drawings in combination with the verting from PDMA to PAA. detailed description presented herein. The description and FIG. 8. Cross-sectional SEM micrographs of the terpoly accompanying drawings may highlight a certain specific mer membranes. The asymmetric structure of the (a) parent example, or a certain aspect of the invention. However, one PI-PS-PDMA and (b) deprotected PI-PS-PAA membranes skilled in the art will understand that portions ofthe example 20 consist ofa selective layer and a gutter layer, which contains or aspect may be used in combination with other examples microscopic voids. In the inset of (b ), a higher magnification or aspects of the invention. micrograph of the PI-PS-PAA top-surface-cross-section FIG. 1. After self-assembly of the block terpolymer to interface shows the structure of the -10 µm active layer as create the nanoporous template and proper structural char it opens into the microporous support layer. acterization, the PtBMA or PDMA (shown in the figure as 25 FIG. 9. SEM micrographs of the top surface of the Block C) can be hydrolyzed to leave a carboxylic acid terpolymer-derived membranes. (a) The active layer surface functionality on the pore walls. This functionality can be of the PI-PS-PDMA parent membrane that was cast from a manipulated to a number of other chemistries to aid in 15% (by weight) polymer solution in a 70/30 (w/w) mixture separation. of dioxane and tetrahydrofuran as solvent with a 75 s FIG. 2. Controlling the copolymer self-assembly is essen 30 evaporation time. (b) The active layer surface ofa converted tial to membrane function. On the left, cylinders oriented PI-PS-PAA membrane. This membrane is produced by soak perpendicular to the free surface produce membranes that ing a parent membrane in a 6 M hydrochloric acid solution function as highly effective membranes. On the right, cyl for 48 hours at 85° C. The structural features ofboth surfaces inders oriented parallel to the free surface produce films that are approximately the same despite the chemical treatment do not provide a useful function. Solvent selectivity and 35 used. solvent evaporation rate are two processing conditions used FIG. 10. Sample data from stirred cell transport tests on in the self-assembly and non-solvent induced phase separa the PI-PS-PAA membrane with a feed solution at pH 4.2. tion (SNIPS) membrane fabrication method that are known The volume ofthe collected permeate is plotted as a function to affect cylinder orientation. of time (a) at various applied pressures where the upper line FIG. 3. PRIOR ART. Cross-sectional SEM image of a 40 corresponds to 40 psi, the middle line corresponds to 35 psi nanoporous triblock terpolymer membrane fabricated using and the lower line corresponds to 30 psi. The slopes ofthese the casting protocol. The figures is from Phillip, et al., Nano lines are used to calculate the fluxes across the membrane, Letters, 2011, 11, 2892 and PCT Publication WO2012/ which are plotted against applied pressure in (b). The slope 151482. Note that at the membrane (the top of the image), of the line in (b) yields a permeability of 0.657 L m-2 h-1 1 the monodisperse pores serve as a thin (-100 nm) selective 45 psi- . layer. These pores have an approximate diameter ofabout 20 FIG. 11. Hydraulic permeabilities ofthe parent and depro nm. However, this membrane lacks the pore wall function tected (i.e., PAA-functionalized) terpolymer membranes ality to be described within (vide infra). plotted vs. solution pH. For pH values ranging from 2-11, FIG. 4. PRIOR ART. SEM micrographs of (a) the com the parent membrane had a constant hydraulic permeability 2 1 1 mercially-available ultrafiltration membrane made using 50 of 6 L m- h- bar- . The PI-PS-PAA membrane had a phase inversion techniques and (b) a membrane formed by permeability of0.6 Lm-2 h-1 bar-1 from pH 4-12. Below pH the self-assembly oftriblock terpolymers. Note that the pore 4, the permeability of the PI-PS-PAA membrane increased size shown in FIG. 4b is -50 nm; this is an order of monotonically; reaching a permeability of 16 L m-2 h-1 magnitude larger than those generated according to embodi bar-1 at pH 1. ments described herein. The figure is from Phillip, et al., 55 FIG. 12. Molecular weight cut-off (MWCO) curves for Nano Letters, 2011, 11, 2892. the parent and deprotected (i.e., PAA-functionalized) mem FIG. 5. 1H NMR spectra of the PI (lower) and PI-PS branes were generated using solutions that contained poly (middle) precursors and the PI-PS-PDMA triblock terpoly ethylene oxide (PEO) molecules as model solutes of known mer (upper). Characteristic peaks from each moiety are size. PEO molecular weights of 1.1, 2.1, 4.0, 6.0, 7.8, and labeled to highlight the relative composition the terpolymer. 60 10.0 kDa were used. The percent rejection was determined FIG. 6. (a) SEC traces of the triblock terpolymer series by taking the ratio ofthe PEO concentration in the permeate with THF as the mobile phase at a flow rate of 1 mL min-1. to the 1 g L-1 feed. The clean shift (i.e., no trailing or coupling signals) indicates FIG. 13. Molecular weight cut-off (MWCO) curves for the ability of the PI homopolymer and the PI-PS diblock the parent and deprotected membranes shown in FIG. 16 copolymer to serve as macroinitiating agents for the syn- 65 plotted here against molecular weight of solute molecules. thesis of the PI-PS-PD MA triblock terpolymer. (b) Small The solutions contained polyethylene oxide (PEO) mol- angle x-ray scattering (SAXS) data of the bulk PI-PS- ecules of 1.1, 2.1, 4.0, 6.0, 7.8, and 10.0 kDa molecular US 10,022,679 B2 5 6 weights. The percent rejection was determined by taking the DETAILED DESCRIPTION ratio ofthe PEO concentration in the permeate to the 1 g L-1 feed. I. Introduction FIG. 14. Gas diaphragm cell experiments were used to determine the permeability of the parent terpolymer mem- 5 This invention allows the manufacture of novel mem brane in the dry state. The membrane was placed between branes with physical and chemical properties that were gas cylinders at high (-12 psig) and low (-0 psig) pressures, previously unachievable. Previous work with block copoly and the pressure change was recorded as a function of time. mers has shown the self-assembly patterns that can be The logarithm of the ratio of the changing pressure differ obtained by controlling the process parameters can be par ence to the initial difference yields is linear with time. The 10 ticularly useful in the design of membranes by enabling the slope is used to determine the permeability for the three formatting of a nanoscale porous pattern of vertically- gases shown above, which suggest average pore sizes in the oriented, closely-packed cylindrical structures embedded range of 50 to 80 nm through the active layer of the within a membrane material. However, prior work has not membrane. The upper line corresponds to helium, the 15 been able to achieve the small pore sizes that would be middle line corresponds to nitrogen and the lower line necessary for the use of these membranes as, for example, corresponds to argon. reverse osmosis membranes. FIG. 15. SEM micrographs ofterpolymer membranes wet By using multiblock copolymers, this present inventors with the ionic liquid 1,3-dimethylimidazolium bis(trifluo have, for the first time, been able to obtain membranes from romethyl)sulfonylamide ([mmim][Tf2N]). (a) The top sur- 20 self-assembled pores with sizes that are small enough to face of the PI-PS-PDMAmembrane contains a combination allow for selective exclusion ofions dissolved in an aqueous of open pores and mushroom-like structures due to the solution based on their size. Data provided herein demon swelling ofthe PDMAchains in [mmim] [Tf2N]. (b) Pores strate sub-nanometer (<1 nm) pores that are capable of are not visible on the top surface of the PI-PS-PAA due to rejection ofeven the smallest ofdissolved ions and are in the the swelling of the PAA chains in [mmim] [Tf2N]. (c) A 25 rage of pore sizes needed for a reverse osmosis or forward higher magnification micrograph of the top surface of the osmosis system. PI-PS-PAA membranes. The present invention comprises membranes and/or films FIG. 16. ATR-FTIR monitoring the conversion ofthe pore fabricated, cast, formed or manufactured from polymers. walls from PDMA to PAA by suspension of the cast mem Such polymers may be self-assembling polymers. As used brane in a 6 M HCl solution at 85° C. as a function of time. 30 herein, a "polymer" comprises a substance that has a The signal at 1600 cm-1 corresponds to the characteristic molecular structure consisting chiefly or entirely of a large carbonyl stretch from the PDMA peak labeled (a), while the number of similar units covalently-bonded together. The absorption at -1700 cm-1 corresponds to characteristic car polymers of the present invention may comprise multiblock bonyl stretch from PAA peak labeled (b). As shown in the polymers. As used herein a "multiblock" polymer is one in 35 uppermost spectrum, peak a deceases with time as PDMA is which there are greater than two distinct polymeric blocks or converted to PAA, where the reaction nears full conversion regions. Multiblock polymers include, but are not limited to at a reaction time of 48 h. The relative intensities are multiblock copolymers, multiblock tri- or terpolymers, tri standardized using the characteristic aromatic C-H block terpolymers, and higher order multiblock polymers stretches labeled (*) of the un-reactive polystyrene domain 40 comprising four, five, six, seven, eight, nine or ten distinct 1 between 3100-3000 cm- . polymer regions or blocks. FIG. 17. ATR-FTIR spectra of a PI homopolymer (a) As used herein, a "multiblock copolymer" is a polymer before and (b) after suspension of the solid in 6 M HCl comprising two or more chemically distinct regions or solution at 85° C. for 72 hours. Analogous data are shown (c) segments (referred to as "blocks") preferably joined in a before and ( d) after suspension of the PI-PS di block copo 45 linear manner, that is, a polymer comprising chemically lymer using the same reaction conditions. During the reac differentiated units which are joined end-to-end. Types of tion of the PI analog in (a) and (b), a small qualitative polymers useful in the present invention are described in decrease in the v c-s and v c-s stretches and the increase in the more detail herein. The membranes and/or films ofthe present invention may vcH2_0 , vc-o, vc~o, and v o-H stretches between (a) and (b) indicates partial oxidation of the RAFT terminus as well as 50 be porous, isoporous or semiporous. As used herein, the term a small hydroxylation of the alkene bonds in the PI block "porous" refers to a material whose molecular structure is permeable to fluid or gas flow. A material which is "semi domain. Using the same reaction conditions of 6 M HCl porous" is porous with respect to some materials and not to solution at 85° C. for 72 hours for the PI-PS diblock analog others. By "isoporous" it is meant that the surface layer of in ( c) and (d), little difference in the aforementioned peaks 55 the membranes or films have a narrow pore size distribution. are detected in the hydroxylation ofthe PI domain indicating These materials are frequently characterized by the size of limited degradation of the PI-PS support. their pores, which are voids in the material: very small pores FIG. 18. The second heating scan of differential scanning having diameters less than 2 nanometers (nm); intermediate calorimetry (DSC) traces of the PI and PI-PS precursor size pores having diameters between 2 and 50 nm; and very samples and the PI-PS-PDMA triblock terpolymer. The 60 large pores have diameters greater than 50 nm. Conventional glass transition temperature (Tg) values for each domain in porous materials have randomly distributed voids that these samples corresponds well with the glass transition exhibit neither shape nor size uniformity. In contrast, voids temperature values measured for equivalently-sized or particles possessing a periodic distribution or lattice are homopolymer analogs. Discrete glass transition tempera referred to as ordered and those having a narrow size and tures in the triblock terpolymers were not observed readily 65 shape distribution are referred to as monodisperse. It is noted due to the close proximity of the glass transition tempera that pore size is typically used in relation to the average tures of PS and PDMA. diameter ofthe pores. The pores may not be exactly circular US 10,022,679 B2 7 8 in cross-section but they are typically cylindrical or tubular the SNIPS methodology have resulted in a limited number structures ofapproximately constant cross sectional area and of pore functionalities. The polystyrene-b-poly(vinyl pyri shape. dine) (PS-PVP) and polyisoprene-b-polystyrene-b-poly(4- Multiblock copolymers can have a range ofdispersity values vinyl pyridine) (PI-PS-P4VP) systems have been demon- (Mw/Mn). For example, the multiblock copolymer can have 5 strated to be hindered by the limited chemical group a dispersity value ( D) ranging from 1.0 to 1.5, including all conversion of the PVP functionality, which resides on the values to the 0.05 and ranges there between. In some pore wall. In addition, the PI-PS-P4VP system relies on embodiments, the dispersity value is equal to or greater than anionically-controlled polymerization mechanisms that can 1 and less than 1.1, equal to or greater than 1 and less than require low temperatures (-78° C.), in situ solvent exchange 1.2, equal to or greater than 1 and less than 1.3, equal to or 10 procedures, and stringent non aura conditions with no for greater than 1 and less than 1 .4, equal to or greater than 1 and eign bodies for high fidelity synthesis on any scale, which less than 1.5. It is desirable that the multiblock copolymer limits the large-scale utility of membranes made from these have a D of 1.01 to 1.4. materials. Another feature of the membranes or films of the inven- As such, a need exists in the art for a methodology that tion is their capacity for functionalization. Functionalization 15 may be chemical or structural. Chemical functionalization of enables the large-scale production of block polymers such the membranes or films of the present invention may occur that nanostructured membranes can be generated that allow or be effected at the membrane surface, the interface for: 1) high selectivity, 2) high flux, 3) straightforward between one or more pores and the membrane or the walls materials syntheses, and 4) generation of tailored pore lining the inside of the pores. Chemical functionalization 20 functionalities. The present invention provides such a solu may be imparted prior to casting the membrane, during the tion. casting process or after casting of the membrane or film. According to one aspect of the present invention, nano structured films or membranes are fabricated which contain II. Fabrication of Membranes tailored pore chemistries. As used herein, a "membrane" 25 refers to a selective barrier that allows, concomitantly with Traditionally, membranes have been fabricated using 1) the flow of a fluid, whether gas or liquid, the passage of phase separation techniques, which result in highly porous certain constituents while retaining other constituents. A membranes, or 2) the high-energy bombardment of dense "film" refers to a layer of material ranging from less than 10 films to produce track-etched membranes that contain a low nm to micrometers in thickness. A membrane may be a film density ofpores with a monodisperse size. However, current 30 and/or a film may act as a membrane. filtration membranes made in these ways are stymied from The polymer membranes and/or films of the present certain applications due to the tradeoffbetween high flux and invention comprise a nanoporous surface active layer and a high size selectivity and the deleterious effects of fouling. microporous support layer. Unless otherwise stated, when Furthermore, current commercial membranes that have nar referring to pore size, it is the pore diameter which is being rowly-distributed pores do not have the ability to separate 35 referenced. Pore sizes of the surface active layer are less materials of similar size with different chemical functional than 5 nm, less than 4 nm, less than 3 nm, less than 2 nm or ities. less than 1 nm. In some embodiments the pore size of the One technique for generating membrane pores with nar active surface layer is less than 0.01 nm or 0.1 nm. row size distributions includes the incorporation of self In some embodiments the pore size of the active surface assembling block polymers as the casting material. This 40 layer is between 0.5 nm-1 nm, between 0.1 nm-0.5 nm or enables the microphase-separated domains of the block between 0.01 nm-1 nm in diameter. polymer to template pore formation. Previously, this has In some embodiments the active surface layer is about occurred using either non-solvent phase separation tech 100 nm thick. The active surface layer may range from 10 niques to generate anisotropic membranes or the self-assem nm to 10,000 nm. In some embodiments the active surface bly of block polymers into ordered nanostructures and the 45 later is less than 100 nm thick. In some embodiments the subsequent removal of one of the phases through selective active surface layer is at least 10 nm, at least 20 nm, at least etching techniques to yield monolithic structures. 30 nm, at least 40 nm, at least 50 nm, at least 60 nm, at least In the phase inversion methodologies, porous charmels 70 nm, at least 80 nm, at least 90 nm or at least 100 nm thick. form as the lyophilic shells of micelles contract during the Pore sizes ( e.g., diameters) ofthe support layer may range casting process. This leaves the volumes previously occu- 50 from 500 nm to 50,000 nm. pied by the solvent-loving moieties as open pores. Mono In some embodiments the support layer is at least 500 nm, lithic membrane pores are produced by the selective etching at least 600 nm, at least 700 nm, at least 800 nm, at least 900 of specific well-ordered nanoscale domains. In both pro nm, at least 1000 nm, at least 1100 nm, at least 1200 nm, at cesses, the resulting membranes have highly uniform pore least 1300 nm, at least 1400 nm, at least 1500 nm, at least sizes. The use of the self-assembly and non-solvent induced 55 1600 nm, at least 1700 nm, at least 1800 nm, at least 1900 phase separation (SNIPS) technique has been favored over nm, at least 2000 nm, at least 2100 nm, at least 2200 nm, at monolithic templates recently due to its ability to make least 2300 nm, at least 2400 nm, at least 2500 nm, at least thinner membranes, which result in higher fluxes without 2600 nm, at least 2700 nm, at least 2800 nm, at least 2900 compromising size selectivity. Another advantage to using nm, at least 3000 nm, at least 3100 nm, at least 3200 nm, at the SNIPS technique is that in some embodiments it does not 60 least 3300 nm, nm least 3400 nm, at least 3500 nm, at least require any selective etching. Furthermore, the SNIPS pro 3600 nm, at least 3700 nm, at least 3800 nm, at least 3900 cess can be modified to coat thin membranes onto a nm, at least 4000 nm, at least 4100 nm, at least 4200 nm, at mechanical support, such as a non-woven fabric, resulting in least 4300 nm, nm least 4400 nm, at least 4500 nm, at least the potential for membrane fabrication on the industrial 4600 nm, at least 4700 nm, at least 4800 nm, at least 4900 scale. 65 nm, at least 5000 nm, at least 10,000 nm, at least 20,000 nm, The SNIPS method is not without limitations. Previous at least 30,000 nm or 40,000 nm thick. The support layer efforts regarding block polymer membranes fabricated via may range from 100 to 100,000 nm in thickness. US 10,022,679 B2 9 10 One embodiment of the invention provides an organic separation, filtration, purification or concentration ofa mate membrane comprising a nanoporous active selective layer, rial (e.g., solid, liquid or gas). wherein the nanoporous active selective layer comprises a plurality of pores, the pores having: III. Polymers of the Invention (i) substantially uniform diameters of less than 5 nm; (ii) standard deviations of the substantially uniform pore A polymer is a structure composed of one or more diameters of less than 1 nm; and monomers. A polymer made from two monomer species is (iii) substantially uniform orientations which are approxi referred to as a copolymer. A copolymer can be further mately perpendicular to surfaces of the membrane. categorized based on the distribution of the monomeric 10 units. For example a copolymer with monomeric species In one embodiment, the films or membranes are fabri- "A" and "B" could be referred to as an alternating copoly- cated from self-assembled triblock terpolymers. mer if the monomeric units are distributed in an alternating Another aspect of the invention utilizes triblock terpoly fashion such as A-B-A-B. A copolymer with monomeric mers that self-assemble into regular structures on the distribution in a pattern such as AAA-BBB is referred to as nanoscale to template the pore structure of our membranes, 15 a block copolymer as the species are arranged in blocks which can result in a membrane that contains a high density along the polymer. The homopolymer units in a block of monodisperse pores, a structural feature that current copolymer are typically linked by a covalent bond. The same membranes lack. The pore size can be tuned by using basic architecture of block copolymers can be extended to well-designed chemical syntheses to control precisely the more complex configurations. For instance, triblock, tetra molecular weight and the molecular weight distributions of 20 block, or multiblock copolymers can also be created. Mul the self-assembling macromolecules. In another aspect of tiblock refers to an unspecified number of blocks that is the invention, the films or membranes will contain a plural- greater than or equal to 2. Similarly, more complex polymers ity of singly-sized pores per square meter. In some embodi that are made up of more than two monomeric species. 14 ments, the membranes or films may have more than 10 , These may be referred to as terpolymer in the case of 3 15 16 17 18 19 10 , 10 , 10 , 10 or 10 pores per square meter. 25 monomeric species, tertrapolymers in the case of 4, or Membrane Functionalization multipolymers in the case of an unspecified number of In one aspect, the macromolecule can be designed so that monomeric species that is greater than or equal to 2. after fabricating large membrane areas using the scalable Membranes can be fabricated from a variety of different SNIPS process, the membrane pores are lined by a func materials including inorganics, such as aluminum oxide or tional moiety that can readily be converted in the solid state 30 zeolites, and organic materials, including myriad polymers. to a myriad of functional groups. This process allows for a Composite membranes, which incorporate inorganic entities "molecule-to-module" control of the membranes. This, in within polymeric matrices, also are explored commonly in turn, allows for the development of structure-property-per the hopes of combining the selectivity of highly-ordered formance relationships in established and emerging mem inorganic structures with the mechanical robustness ofpoly brane separations. Importantly, these relationships can be 35 meric materials. However, the versatility and ease of pro utilized to optimize the design of membranes in a rational cessing associated with polymeric systems make them the and systematic manner. standard material for most conventional membrane fabrica Furthermore, the pore chemistry of the membrane can be tion. tailored for the specific needs of a given separation by Polymers useful in the present invention include, but are controlling the chemical constituents and the distribution of 40 not limited to, polystyrenes, polyesters, polyamides, poly functionality along the polymer backbone of the macromol ethylene glycols, polyethers, polyetherimides, polyvinylal ecule. cohols or polyvinylchlorides and derivatives or combina According to the present invention, the membranes may tions thereof. Polymers may be biodegradeable or be functionalized at the surface, internally or at an interface, biocompatible. They may be purchased from any supplier, such as the internal face of a pore. Such functionalization 45 for example Sigma Aldrich (Natick, Mass.) supplies PEG includes the incorporation of a reactive group. Examples of b-PLA, PEG-b-PLGA, PEG-b-PS, PEG-b-PCL, PEG-b-PE, reactive groups or moieties which may be incorporated into PS-b-PMMA, PS-b-PA diblock copolymers, among others. the membranes of the present invention include, but are not As such, the Sigma Aldrich catalog is incorporated herein by limited to an alcohol, hydroxyl, carbonyl, aldehyde, thiol, reference in its entirety. Any of these copolymers may be ketone, acyl halide, carbonate, carboxylate, carboxylic acid, 50 used in the present invention. ester, methoxy, hydroperoxide, peroxide, ether, hemiacetal, According to the present invention, any of the monomers hemiketal, acetal, ketal, acetal, orthoester, heterocycle, referenced herein, whether alone or as a component of a di orthocarbonate ester, amide, amine, imine, imide, azide, or tri-polymer may serve as a monomer of the invention. cyanate, nitrate, nitrile, nitrite, nitro compound, nitroso Examples of monomers useful in the present invention compound, pyridine, pyridine derivative, thiol, sulfide, thio 55 include, but are not limited to DMA, tBMA, poly(( 4-vinyl) ether, disulfide, sulfoxide, sulfone, sulfinic acid, sulfonic pyridine), poly((2-vinyl) pyridine), poly (ethylene oxide), acid, thiocyanate, thione, thial, phosphine, phosphane, phos poly(methacrylates) such as poly(methacrylate), poly(m phonic acid, phosphate, phosphodiester, boronic acid, ethyl methacrylate), poly(dimethylethyl amino ethyl meth- boronic ester, borinic acid, borinic ester, carboxylic acid, acrylate), poly(acrylic acid), and poly(hydroxystyrene). alkyl group and a combination thereof. 60 Examples of copolymers useful in the present invention In some embodiments, the functionalization varies with include, but are not limited to, poly(styrene)-b-poly((4- pH, the wet/dry state, or with temperature. For example, vinyl) pyridine), poly(styrene)-b-poly((2-vinyl) pyridine), functionalization may comprise a zwitterionic moiety whose poly(styrene )-b-poly(ethylene oxide), poly(styrene )-b-poly ionic state varies with pH. Such versatility in a membrane (methyl methacrylate), poly(styrene )-b-poly(acrylic acid), expands the use of the membranes or films or devices to 65 poly(styrene)-b-poly(dimethylethyl amino ethyl methacry areas oftechnology or biology (including agriculture) where late), poly(styrene)-b-poly(hydroxystyrene ), poly(a-methyl environmental conditions dictate unique requirements for styrene )-b-poly(( 4-vinyl) pyridine), poly(a-methyl styrene)- US 10,022,679 B2 11 12 b-poly((2-vinyl) pyridine), poly(a-methyl styrene )-b-poly azoles, polybenzothiazinophenothiazines, polybenzothiaz ( ethylene oxide), poly( a-methyl styrene)-b-poly(methyl oles, polypyrazinoquinoxalines, polypyromellitimides, methacrylate), poly( a-methyl styrene )-b-poly(acrylic acid), polyquinoxalines, polybenzimidazoles, polyoxindoles, poly(a-methyl styrene )-b-poly(dimethylethyl amino ethyl polyoxoisoindolines, polydioxoisoindolines, polytriazines, methacrylate), poly(a-methyl styrene)-b-poly(hydroxysty - 5 polypyridazines, polypiperazines, polypyridines, polypip rene), poly(isoprene)-b-poly(( 4-vinyl)pyridine), poly(iso eridines, polytriazoles, polypyrazoles, polypyrrolidines, prene)-b-poly((2-vinyl) pyridine), poly(isoprene )-b-poly polycarboranes, polyoxabicyclononanes, polydibenzo ( ethylene oxide), poly(isoprene)-b-poly(methyl furans, polyphtalides, polyacetals, polyvinyl ethers, polyvi methacrylate), poly(isoprene )-b-poly(acrylic acid), poly nyl thioethers, polyvinyl ketones, polyvinyl halides, poly (isoprene)-b-poly( dimethylethyl amino ethyl methacrylate ), 10 vinyl nitriles, polyvinyl esters, polysulfides, polythioesters, poly(isoprene )-b-poly(hydroxystyrene ), poly(butadiene)-b polysulfones, polysulfonamides, polyureas, polyphospha poly(( 4-vinyl)pyridine ), poly(butadiene)-b-poly((2-vinyl) zenes, polysilazanes, polysiloxanes, polyolefins, or the like, pyridine), poly(butadiene)-b-poly( ethylene oxide), poly or a combination comprising at least one of the foregoing (butadiene )-b-poly(methyl methacrylate ), poly(butadiene) polymers. b-poly(acrylic acid), poly(butadiene)-b-poly( dimethyl ethyl 15 Examples of hydrophilic synthetic polymers useful in the amino ethyl methacrylate), and poly(butadiene)-b-poly(hy present invention include polyarylsulfones, polyanhydrides droxystyrene). and polysulfonates and combinations thereof. It is understood that monomers and copolymers may be Several novel materials have recently been proposed as a combined in any order to produce a terpolymer or triblock possible way of making membranes with higher permeabil copolymer. Examples ofthese include, but are not limited to, 20 ity including the use of carbon nano-tubes (CNTs ), graphene poly(isoprene-b-styrene-b-4-vinylpyridine), poly(isoprene) or use of aquaporins in membranes. (Aquaporins are the b-poly(styrene)-b-poly(( 4-vinyl)pyridine), poly(isoprene) proteins responsible for water filtration in many human and b-poly(styrene)-b-poly((2-vinyl) pyridine), poly(isoprene) animal cells). While these approaches have the potential to b-poly(styrene)-b-poly( ethylene oxide), poly(isoprene)-b deliver very high flow rates, there are significant manufac poly(styrene)-b-poly(methyl methacrylate ), poly(isoprene )- 25 turing challenges with developing these types ofmembranes b-poly(styrene)-b-poly(acrylic acid), poly(isoprene )-b-poly at a larger scale. The present invention contemplates the use ( styrene )-b-poly( dimethylethy I amino ethy I methacry late), of such non-traditional polymer substances. poly(isoprene )-b-poly( styrene )-b-poly(hydroxystyrene ), Polymers: Self Assembling. poly(isoprene )-b-poly( a-methyl styrene)-b-poly(( 4-vinyl) As the development of nanoscale mechanical, electrical, pyridine), poly(isoprene)-b-poly( a-methyl styrene )-b-poly 30 chemical and biological devices and systems increases, new ((2-vinyl) pyridine), poly(isoprene )-b-poly(a-methyl sty processes and materials are needed to fabricate nanoscale rene)-b-poly( ethylene oxide), poly(isoprene)-b-poly( a devices and components. The use of self-assembling block methyl styrene)-b-poly(methyl methacrylate), poly copolymers presents another route to patterning at nanome (isoprene)-b-poly( a-methyl styrene )-b-poly(acrylic acid), ter dimensions. The self-assembly properties of certain types poly(isoprene )-b-poly( a-methyI styrene )-b-poly( dimethy 1- 35 ofpolymers broadly defined as block copolymers have been ethyl amino ethyl methacrylate), poly (butadiene)-b-poly investigated as a possible approach to making membrane ( styrene )-b-poly( (4-vinyl)pyridine ), poly(butadiene )-b-poly materials. (styrene )-b-poly((2-vinyl) pyridine), poly(butadiene )-b-poly One embodiment of the invention provides a method for (styrene )-b-poly( ethylene oxide), poly(butadiene )-b-poly forming a nanostructured membrane of a self-assembled (styrene )-b-poly(methyl methacrylate), poly(butadiene)-b - 40 A-B-C multiblock copolymer, the method comprising the poly(styrene)-b-poly(acrylic acid), poly(butadiene )-b-poly steps of: ( styrene )-b-poly( dimethylethy I amino ethy I methacry late), a) synthesizing the self-assembled A-B-C multiblock poly(butadiene )-b-poly( styrene )-b-poly(hydroxystyrene ), copolymer using a controlled radical polymerization poly(butadiene )-b-poly( a-methyl styrene)-b-poly(( 4-vinyl) mechanism; and pyridine), poly(butadiene )-b-poly( a-methyl styrene )-b-poly 45 b) fabricating the nano structured membrane from the ((2-vinyl) pyridine), poly(butadiene)-b-poly( a-methyl sty self-assembled A-B-C multiblock copolymer using a rene)-b-poly( ethylene oxide), poly(butadiene)-b-poly( a non-solvent induced phase separation [SNIPS]; methyl styrene)-b-poly(methyl methacrylate), poly wherein the multiblock copolymer comprises a terpoly (butadiene )-b-poly(a-methyl styrene)-b-poly(acrylic acid), mer that comprises polyisoprene-b-polystyrene-b-poly poly(butadiene )-b-poly( a-methyl styrene )-b-poly( dimethyl- 50 (N,N-dimethylacrylamide) [PI-PS-PDMA] or polyiso ethyl amino ethyl methacrylate ), and poly(butadiene )-b-poly prene-b-polystyrene-b-poly(tert-buty lmethacrylate) ( styrene )-b-poly(hydroxystyrene). [PI-PS-PtBMA]. Examples ofhydrophobic synthetic polymers useful in the Another embodiment of the invention provides a nano present invention include polyacetals, polyolefins, polycar structured membrane of a self-assembled A-B-C multiblock bonates, polystyrenes, polyesters, polyamides, polyami- 55 copolymer, wherein the copolymer comprises a terpolymer deimides, polyarylates, polyethersulfones, polyphenylene that comprises polyisoprene-b-polystyrene-b-poly(N,N-di sulfides, polyvinyl chlorides, polysulfones, polyimides, methylacrylamide) [PI-PS-PDMA] or polyisoprene-b-poly polyetherimides, polytetrafluoroethylenes, polyetherke styrene-b-poly(tert-butylmethacrylate) [PI-PS-PtBMA]. tones, polyether etherketones, polyether ketone ketones, Any of the polymers disclosed herein or known to those polybenzoxazoles, polyphthalides, polyacetals, polyanhy- 60 of skill in the art may be utilized to generate self-assembled drides, polyvinyl ethers, polyvinyl thioethers, polyvinyl polymeric structures of the invention. ketones, polyvinyl halides, polyvinyl nitriles, polyvinyl The self-assembly of block polymers occurs due to an esters, polysulfonates, polysulfides, polythioesters, polysul inherent tradeoff that occurs while the materials attempt to fones, polysulfonamides, polyureas, polyphosphazenes, reach a lowest-energy conformation. In particular, the mac polysilazanes, polyethylene terephthalate, polybutylene 65 romolecules attempt to minimize the enthalpic penalty asso terephthalate, polyurethane, polytetrafluoroethylene, poly ciated with interactions between chemically-incompatible chlorotrifluoroethylene, polyvinylidene fluoride, polyoxadi- blocks while also minimizing the amount of chain stretching US 10,022,679 B2 13 14 (as chain stretching decreases the amount of configurational TABLE I-continued entropy associated with the macromolecules increases). As such, the block polymers self-assemble on a less than 1 nm Membrane types and pore size to 100 nm length scale, as they are limited by the inherent Membrane type Pore Size lengths of their molecular bonds. The exact geometries, 5 domain spacings, and alignments of these block polymers Nanofiltration (NF) 10-1 nm Reverse Osmosis (RO) <1 nm can be controlled simply by tailoring the chemistry and (also Forward Osmosis (FO)) processing of these nanomaterials. IV. Uses of the Membranes, Polymers, and 10 There are substantial differences in the mechanisms by Methods of the Invention which these membranes are able to operate successfully. MF membranes are capable of disallowing passage of bacteria According to the present invention, the membranes, films and suspended solids but tends to allow the passage of and/or devices described herein may be used to effect viruses, ions, and water molecules as these are smaller in separations, concentrations, purifications, extractions, chro 15 size and can easily pass through the MF membranes' rela matography, or filtrations of solid, liquid or gaseous medi tively large pores. In addition to what a MF membrane is ums, either alone or in combination. In some cases the goal capable of excluding, MF membranes can also be used to may be to collect the separated materials, such as the remove viruses, and as we move onto the smaller pore sizes extraction of oil or valuable minerals or materials from of NF membranes some of the larger multivalent ions can water sources. In other embodiments, these two goals may 20 also be removed. Reverse osmosis membranes can effec be simultaneously pursued, with the objective of cleaning tively remove even the smallest ofdissolved ions and mostly water and at the same time collecting and extracting value allows only the passage of water molecules, which are smaller in size than most ions. MF, UF and NF membranes' from some of the removed contaminants. Water Treatment, Purification, and Separations selectivity is based substantially on a size-exclusion mecha- In various embodiments, the invention provides methods 25 nism, where only matter that is smaller than the membrane of preparing multiblock copolymers and methods for using pore size is capable of passing through the membrane, while the membranes, including membranes that have important matter that is larger than the pore sizes is disallowed passage filtration properties. In this context, the present invention through the membrane. In order for the membrane to be finds utility in processes to purify, desalinate, or decontami effective there needs to be a low pore size variability such nate water sources in order to obtain cleaner water. 30 that most of the pores are of substantially similar size. Otherwise, a membrane's selectivity would be compro Fresh water is an increasingly-scarce world resource and there is a growing demand for more efficient and productive mised, as larger matter would be able to pass through the ways to clean contaminated water sources and to create larger pores. more fresh water. Membrane technologies have been estab Current technology has not been capable of creating an lished as the predominant water treatment technology and 35 RO membrane with consistently-sized pores in the sub 1 nm are used in various different systems ranging from micro range. Instead, current RO membranes are created with filtration (MF), ultrafiltration (UF), nanofiltration (NF), and tortuous paths, such that any molecule that traverses the reverse osmosis (RO) membranes. These membranes can be membrane travels a distance that is usually much larger than classified based on their typical pore sizes, which are sum the thickness of the membrane. These paths through the marized in the Table 1. While there are slight variations in 40 membrane can be thought of as a complex networked mesh the exact definition of these pore size ranges across the of pores and apertures that are connected by passages of literature, and while there is no official definition most varying sizes. Traversing this circuitous path through the definitions are relatively similar. ' membrane is easier for small water molecules as there are The ubiquity of water treatment schemes is not surprising numerous possible paths that it can take as it crosses the given its fundamental connection to life. The membranes 45 membrane. Being larger in size, dissolved ions have a much and films ofthe present invention may be used across a wide more difficult time finding a path through the membrane that range of applications, including treating waste water in they can fit through and will tend to take a longer path as membrane bio-reactors, treating oil and gas water to meet they traverse the membrane. The net result is that the discharge requirements, remediation ofcontaminated waters membrane allows the passage of water molecules at a rate from mining operations, desalinating seawater, brackish 50 that is orders ofmagnitude higher than the rate at which ions water desalination, municipal water treatment, viral separa can pass. This difference in permeabilities results in the very tions in bio-pharmaceutical manufacturing, treating of high rejection rates seen in today's RO membranes. One of power plant cooling water, food and beverage manufactur the consequences of this membrane architecture is that it ing, pulp and paper processing, and many more applications. reduced the attainable flow rate through the membrane. A person skilled in the art will understand that the same 55 Current RO membranes suffer from disappointingly low types of membranes, methods or processes applied to any permeabilities and also require a higher operating pressure given aqueous substance can be applied to numerous other to overcome the low permeability. These factors translate applications. into higher operating costs and capital costs. In contrast to UF and MF that tend to be low-pressure applications, RO 60 systems are typically high-pressure applications. The mini TABLE 1 mum amount of energy needed in order to separate the Membrane types and pore size dissolved solutes from the water solution is known as the osmotic pressure. RO systems must operate at a pressure that Membrane type Pore Size is higher than the osmotic pressure. An alternative approach Microfiltration (MF) 1,000-100 nm 65 to RO is the use offorward osmosis (FO) membranes. In FO Ultrafiltration (UF) 100-10 nm instead of applying pressure to overcome the osmotic pres sure gradient, FO systems expose one side of the membrane US 10,022,679 B2 15 16 to a solution that has a higher osmotic pressure which acts In like fashion, radioactive isotopes may also be removed as a draw solution and results in the flow of water from the from water sources or waste water. Biomolecules such as low osmotic pressure solution to the high osmotic pressure hormones (e.g., estrogen) may be removed from water solution. supplies using the membranes, films or devices of the The membranes and films of the present invention solve 5 present invention. these problems. Semiconductor Industry Bio separations According to another aspect of the present invention, the In addition to water treatment, ultrafiltration (-10-100 nm membranes and/or films or devices comprising the same, pore size) and nanofiltration (-1-10 nm in pore size) mem may be used in the semiconductor industry for the produc- branes are widely-used to effect size-selective separations in 10 tion of ultra-pure water. the pharmaceutical industries. For example, metals, bacteria, Military and Field Applications viruses, and other organic matter have been separated selec According to yet another aspect of the present invention, tively from aqueous solutions using ultrafiltration (UF) and the membranes, films and devices are useful to be deployed in remote or exigent circumstances including but not limited nanofiltration (NF) membranes. Furthermore, UF and NF 15 to remote areas, military installations, situations involving membranes have been used to mediate mass transfer in drug urgent or disaster relief, humanitarian missions and the like. delivery, micropatterning, and biological sensing and immo bilization applications. As such, controlling the material EXAMPLES compositions and nanostructures of these technology plat forms is of prime import. The membranes of the present 20 The following Examples are intended to illustrate the invention address these problems. above invention and should not be construed as to narrow its Furthermore, membrane separation technologies are used scope. One skilled in the art will readily recognize that the heavily in the purification ofmonoclonal antibodies (mAbs ). Examples suggest many other ways in which the invention However, current commercial membranes do not allow for could be practiced. It should be understood that numerous high throughput processing, which leads to high costs for 25 variations and modifications may be made while remaining these therapeutics, and thus, their reduced usage in clinical within the scope of the invention. settings. The high cost of large-scale mAbs production and isolation has hampered their widespread usage in clinical Example 1. General Methods settings. While membrane technologies dominate the mAbs purification market, currently-used commercial membranes 30 Nuclear Magnetic Resonance (NMR) rely on an active layer structure with a wide distribution of The lH NMR spectra were measured on a Bruker pore sizes, which hinders their use in the step that brings the DRX500 spectrometer using a -1 wt % polymer solution in final drug purity to the high level demanded of modern deuterated chloroform (Sigma-Aldrich). Size exclusion therapeutics. This situation results in the need to use chro chromatography (SEC) data were collected on a Hewlett matography colunms, which greatly lowers throughput and 35 Packard 1260 Infinity series equipped with a Hewlett increases patient costs. As such, a need exists for a high Packard G1362A refractive index (RI) detector and three throughput, low-cost biopharmaceutical purification tech PLgel 5 µm MIXED-C colunms. The mobile phase was nique with easily tunable selectivity toward specific bio comprised oftetrahydrofuran (THF) at 35° C. at a flow rate chemicals in order to advance the clinical treatment and of 1 mL min-1 The SEC was calibrated using polystyrene health of a wide variety of patients. 40 standards (Agilent Easi Cal) with molecular weights ranging 1 1 The present invention improves the design of biosepara from 1 kg mo1- to 200 kg mol- . Differential scanning tions devices in order to create high flux and high throughput calorimetry (DSC) data were collected using a TA Instru membranes for improved production and lowered costs of ments Q20 Series differential scanning calorimeter. The biopharmaceuticals. The present invention embraces and samples were initially heated to 200° C., held isothermally characterizes novel multiblock copolymers that self-as- 45 for 10 minutes before being cooled to - 75° C. under a semble into useful nanoscale structures. This next-genera nitrogen gas purge. The data shown are from the final scan 1 tion "molecule-to-module" approach allows one to design from - 75° C. to 200° C. at 10° C. min- . high performance biomedical separations devices in an Attenuated Total Internal Reflectance-Fourier Transform unambiguous and straightforward manner. The unique abil- Infrared (ATR-FTIR) ity to tune membrane nanostructure and tailor pore chem- 50 Attenuated total internal reflectance-Fourier transform istry allows energy-efficient, environmentally responsible infrared (ATR-FTIR) spectroscopic measurements were separation devices to be deployed in place of current acquired using a Thermo-Nicolet Nexus FTIR equipped technologies. with a diamond substrate. Under a constant purge of nitro Remediation and/or Removal ofHarmful Elements, Isotopes gen, the ATR-FTIR data was collected in 32 scans in the 1 or Biomolecules 55 range of 4500-800 cm- using a DTGS KBr detector and According to one aspect of the present invention, the KBr beam splitter. Small angle x-ray scattering (SAXS) membranes or films may be used to remove certain harmful measurements of the powder, containing -1% (by weight) elements from water sources. One such application is the butylated hydroxytoluene (BHT), were prepared by pressing removal of selenium. In one embodiment, the membranes or a 2 mm thick polymer disc into a washer using a Carver films of the present invention are used alone or in a device 60 press. The powder sample was then annealed at 180° C. for for the purpose of clearing or cleaning water run off or in 24 h under vacuum and then cooled to room temperature. remediation of water for purposes other than drinking. SAXS experiments were conducted at beamline 1-4 of the In another approach, magnesium may be removed from Stanford Synchrotron Radiation Laboratory (SSRL). seawater using the membranes or films of the present Monomers and Solvents. invention. In one embodiment such membranes may be used 65 All chemicals were purchased from Sigma-Aldrich unless in conjunction with, either tandem or serially, with tradi otherwise noted. Degassed, inhibitor free tetrahydrofuran tional RO systems. (THF) (Sigma-Aldrich) was purified by passage through an US 10,022,679 B2 17 18 alumina colunm (Innovative Teclmology). Isoprene, styrene, To prepare a membrane, the solution was drawn into a thin and N,N-dimethylacrylamide were purified by passage film on a glass substrate using a doctor blade set at a gate through a basic alumina (Fisher Scientific) colunm prior to height of 254 µm. After casting, the solvent was allowed to use. A Millipore water purification system (Milli Q Advan evaporate from the film for 75 s, and the film was plunged tage AlO, Millipore Corporation, Bilerica, Mass.) provided 5 subsequently into a non-solvent (DI water) bath to induce deionized water, which was used as the non-solvent during polymer precipitation. After fabrication, membranes were membrane fabrication, in preparing solutions for permeabil stored in DI water to prevent drying and cracking of the ity and solute rejection tests, and for rinsing the test cell at films. the conclusion of an experiment. Preparation of Membrane Samples for Structural Charac- Polymer Synthesis and Characterization. 10 terization. In preparation for scanning electron microscopy Synthesis of Polyisoprene. A reversible addition-fragmen (SEM) analysis, 1 cmxl cm sections ofthe membranes were tation chain transfer (RAFT) polymerization mechanism cut from larger sheets, air-dried, and then fixed onto a was utilized for the synthesis of polyisoprene (see Jitchum standard SEM pin stub mount (Ted Pella Inc., Redding, and Perrier, Macromolecules 2007, 40, 1408-1412; Germack Calif.) using carbon tape. For cross-sectional micrographs, et al., J. Polym. Sci., Part A: Polym. Chem. 2007, 45, 15 dried samples were submerged in liquid nitrogen for 15 4100-4108). The polymerization was performed in a 25 mL seconds and then cracked before being taped onto a verti- vacuum flame-dried reaction flask containing a Teflon cally-walled SEM pin stub. All samples were sputter-coated coated magnetic stir bar. 15 mL (0.15 mo!) of isoprene, 24.2 with 1.5 nm ofiridium prior to loading them into a Magellan mg (0.07 mmol) of 2-(dodecylthiocarbonothioylthio )-2- 400 Field Emission Scanning Electron Microscope. Micro methylpropanoic acid (chain transfer agent) and 2.5 µL (0.01 20 graphs were produced using a working distance of3 mm and mmol) of tert-butyl peroxide were added to the reaction an accelerating voltage between 1-3 kV. flask. Once the solids were dissolved completely in the To prepare a membrane sample wetted with ionic liquid solution, four freeze-pump-thaw cycles were performed. for SEM imaging, the membrane was fixed on a pin stub and Next, the reaction flask was refilled with argon and the 2-3 drops of ionic liquid were placed on top of the mem reaction was heated to 120° C. The solution in the reaction 25 brane. After allowing the ionic liquid to soak into the flask was stirred at 120° C. for 40 hours. The mixture was membrane for 5 minutes, the surface was wiped with a cooled to room temperature, precipitated in methanol three lint-free tissue to remove the excess liquid. The sample was times, and the product (PI) dried under vacuum for 24 hours then coated with 1.5 nm ofiridium, and another 1-2 drops of (Mn=14.2 kDa via 1H NMR; D=l.3). ionic liquid were added. After the removal of excess liquid, Synthesis of Polyisoprene-b-Polystyrene. The polymer 30 the samples were dried in a vacuum oven to remove residual ization was performed in a 25 mL flame-dried reaction flask water. containing a Teflon-coated magnetic stir bar. 0.94 g (0.07 AFM experiments were carried out as described in the mmol of chain transfer end groups) of PI, 11.6 mL (0.10 literature (Jing et al., Chem. Sci. 2013, 4, 3818-3826, the mo!) of styrene, 1.4 mole equivalents of dioxane (0.14 mo!, contents of which are incorporated herein by reference in 12.0 mL), and 0.872 mg ofAIBN (5.3 µmo!) were added to 35 their entirety). The characterization was performed in tap the reaction flask. Once the solids were dissolved com ping mode (Multimode, Nanoscope IV Controller, Veeco) pletely in the solution, four freeze-pump-thaw cycles were with a waterproof scanner (J Scanner, Veeco) and a silicon performed. Next, the reaction flask was refilled with argon nitride probe (NP, Veeco). The PI-PS-PAA sample was and the reaction was heated to 60° C. The reaction was tested in dry state and in two aqueous buffer solutions, 50 stirred at this temperature for 4.25 days. The mixture was 40 mM acetic acid (pH=2.98) and 50 mM ammonium acetate cooled to room temperature, precipitated in methanol three (pH=6.88). The apparatus was washed thoroughly after each times, and the product (PI-PS) was dried under vacuum for image with buffer solutions. 24 hours (Mn=45.3 kDa via lH NMR; D =1.2). Solid State PDMA to Poly(Acrylic Acid) (PAA) Conversion Synthesis of Polyisoprene-b-Polystyrene-b-Poly(N,N-Di Protocol. methylacrylamide). The synthesis of the PDMA block was 45 The conversion of the PDMA domain to PAA is based on performed in a 100 mL flame-dried reaction flask containing protocols described in the literature (Rzayev and Hillmyer, a Teflon-coated magnetic stir bar. 1 g (22.0 µmo! of chain J. Am. Chem. Soc. 2005, 127, 13373-13379). A section of transfer end groups) of PI-PS, 15.8 mL (0.15 mo!) of the membrane was submerged in a 6 M HCI aqueous N,N-dimethylacrylamide, 3 volume equivalents of THF solution at 85° C. for a predetermined period of time. After (47.5 mL) and 0.45 mg (2.8 µmo!) of AIBN were added to 50 removal from the acidic solution, the membrane material the reaction flask. Once the solids were dissolved com- was washed repeatedly in DI water. The converted mem- pletely in the solution, four freeze-pump-thaw cycles were brane was then analyzed using ATR-FTIR spectroscopy and performed. Next, the reaction flask was refilled with argon transport testing. and the reaction was heated to 60° C. The reaction was Transport Tests (Solvent Flow, Solute Rejection, and Gas stirred at this temperature for 1.3 hours. The mixture was 55 Permeability). cooled to room temperature, precipitated in cold hexanes Stirred Cell Experimental Design. Transport tests were three times, and the product (PI-PS-PDMA) dried under performed in a 10 mL Amicon 8010 stirred cell. A 1-inch vacuum for 24 hours (Mn=68.6 kDa via lH NMR; D =1.3). diameter circular section ofa PI-PS-PDMA (or PI-PS-PAA) Membrane Fabrication and Structural Characterization. membrane was fabricated using a standard hand punch. A Membrane Casting Procedure. Membranes were cast 60 I-inch diameter piece ofCrane calendered PP/PE nonwoven using the self-assembly and non-solvent induced phase microporous substrate was placed in the bottom of the separation (SNIPS) method. The casting solutions were stirred cell for support, and the membrane was placed on top prepared by dissolving the PI-PS-PDMA terpolymer at a of this support. The stirred cell was filled with 10 mL of concentration of 15 wt % in a 70/30 (w/w) mixture of solution, then capped, and pressurized with nitrogen. The dioxane and tetrahydrofuran. After the terpolymer was dis 65 permeating solution was collected in a vial that rested on a solved completely, the solution was allowed to sit unstirred balance. The mass of the vial was collected at regular overnight to ensure no air bubbles were trapped in solution. intervals in order to calculate the water flux. The hydraulic US 10,022,679 B2 19 20 permeability ofthe membrane was determined by measuring well-designed macromolecules. By rational design of the water flux at various applied pressures. chemical reaction mechanisms and chemical functionality, pH-Dependent Permeability Tests. The hydraulic perme one can generate triblock terpolymers with easily control ability was measured using solutions of varying acidity and lable and highly tunable molecular weights, molecular basicity for the parent and PAA-functionalized membranes. 5 weight distributions, and chemical compositions. Manipu Acidic solutions (1 Scheme 1. Synthesis ofthe polyisoprene-b-polystyrene-b-poly(N,N-dimethylacrylamide) (PI-PS-PDMA) triblock terpolymer. PI 0 HO AIBN, 60° C. PI-PS AffiN,W° C, '-, ~ N 0 I US 10,022,679 B2 29 30 -continued HO PI-PS-PDMA A combination of 1 H NMR spectroscopy and size exclu diameter of 53 nm and a standard deviation of 20 nm (FIG. sion chromatography (SEC) indicated the synthesis of a 9a). Below the dense layer, the membrane quickly opens relatively low dispersity, high molecular weight triblock 15 into macrovoids that are characteristic ofmembranes formed terpolymer. The PI, PS, and PDMA blocks had 1 H NMR via phase inversion, rather than terpolymer self-assembly. determined molecular weights of 14.2 kDa, 31.1 kDa and Due to the relatively large sizes of these voids, this under 23.3 kDa, respectively (FIG. 5). This corresponds to a lying layer provides minimal resistance to flow while pro volume fraction of 24%, 46% and 30%, respectively (based viding mechanical support to the selective layer, which 20 on the following values ofthe homopolymer densities at 25° increases the durability of the membrane. 3 3 C.: pPI=0.92 g cm- , PPs=l.06 g cm- , and PPDMA=l.21 g Hydraulic Permeability 3 cm- ). The terpolymer had a dispersity ( D) value of 1.3, The hydraulic permeability of the parent membrane was based on polystyrene standards (FIG. 6a). determined by measuring the water flux at applied pressures The specific triblock terpolymer composition was tar- 25 ranging from 5 to 40 psi. They withstood repeated operation geted because prior work that used self-assembled block at an applied pressure of 40 psi easily. Furthermore, in polymers as templates for the nanostructure ofporous mem practical application these membranes will be cast on a branes suggested that a hexagonally close-packed (HCP) microporous support to help improve their mechanical sta geometry in the powder state is conducive to the formation bility. The water flux vs. applied pressure data were fit with of high quality membranes. SAXS analyses of the pressed 30 a linear equation, whose slope is equal to the hydraulic powder PI-PS-PDMA sample were consistent with the HCP permeability (FIG. 10). morphology with peaks shown at 1, v3, v4, v7 and v9 In FIG. 11, the squares represent the hydraulic perme multiples of the principal reflection, q* (FIG. 6b). ability of the parent membrane for feed solutions of pH 2.5, The triblock terpolymer, PI-PS-PDMA, was synthesized 5.5, and 10.5. Over this pH range, the hydraulic permeability 2 instead of a diblock copolymer analog, PS-PD MA, because 35 ofthe parent membrane was constant at a value of-6 L m- 1 1 incorporating the rubbery, low Tg PI block improves the h- bar- . This indicates that the PDMA groups (pKa=7.3) mechanical response of the ultimate membrane. Tensile lining the pore walls are not affected by the pH of the testing conducted using the bulk PI-PS-PDMA material solution. (FIG. 7) supports this hypothesis. Specifically, the mechani- Molecular weight cutoff tests were performed on the cal toughness of the PI-PS-PDMA sample is consistent with 40 parent membrane to probe its ability to reject molecules the toughness of PI-PS-P4VP terpolymers studied in prior based on differences in solute size. In these experiments, the work that demonstrated the advantages of moving from membrane was challenged with solutions containing PEO diblock to multiblock systems when fabricating nanostruc molecules ranging in molecular weight from 1.1 to 10 kDa. tured porous materials. Using literature data for the intrinsic viscosity and diffusion Asymmetric membranes were fabricated from the PI-PS- 45 coefficients of PEO, the hydrodynamic radii were calculated PDMA terpolymer using the SNIPS technique. Briefly, the to range from 0.75 to 3.0 nm. terpolymer was dissolved at a concentration of 15% (by Percent Rejection weight) in a mixed solvent, which consisted of dioxane and Percent rejection values were calculated by comparing the tetrahydrofuran combined at a 7/3 (w/w) ratio. The resulting concentration of PEO in the solution that permeated the solution was drawn into a thin film and solvent was allowed 50 membrane to the concentration of PEO in the initial feed to evaporate for 75 s. Then, the thin film was plunged into solution. The results of the solute rejection experiments are a DI water bath to fix the membrane structure in place. The represented by the squares in FIG. 12; a MWCO curve (i.e., anisotropic structures of the membranes produced by the solute rejection plotted against molecular weight) is pro SNIPS method are displayed in the cross-sectional SEM vided in FIG. 13. During these experiments, the feed solu micrographs shown in FIG. 8. These micrographs indicate 55 tions were stirred at 400 rpm to produce mass transfer 5 1 that the total membrane thickness (-40-50 µm) consists of coefficients, k, on the order of 1.0xl0- m s- , while the two sections, a denser top (selective) layer and a more water flux, Jw, during the MWCO tests was equal to 7.9x 7 1 porous underlying (gutter) layer. 10- m s- . Because this results in a J,Jk value around 0.13, The -10-micrometer-thick dense layer is situated at the which is significantly lower than the suggested limit where top of the micrograph, which corresponds to the surface of 60 concentration polarization becomes severe, the presented the membrane that was exposed to the atmosphere during results are solely a function of the ability of the terpolymer solvent evaporation. The terpolymer concentration in this membrane to separate solutes based on size. region increases significantly during the evaporation step For the parent membrane, solutes with a hydrodynamic causing the terpolymer to self-assemble and template the radius greater than 2.2 nm, (i.e., the 6.0 kDa PEO molecule) nanostructure of the membrane in this upper region. A 65 were almost completely rejected. Molecules with hydrody micrograph ofthe top surface ofthe parent membrane shows namic radii smaller than 1.2 nm (i.e., the 2.1 kDa PEO an average of 9.4xl013 pores m-2 with an average pore sample) permeate through the membrane with little (-4%) US 10,022,679 B2 31 32 rejection. The 4.0 kDa PEO sample, which has a hydrody tains PDMA-lined nanopores that provide the ability to namic radius equal to 1.7 nm, was only partially rejected tailor the chemical functionally of the membrane post fab (60% rejection). This point of datum, in conjunction with rication. Taking advantage of this useful property requires established theories for size-selective separations, was used the conversion of the PDMA block to the carboxylic acid to estimate the pore size of the parent membrane at 8 .1 nm 5 derivative, poly(acrylic acid) (PAA); previously, it has been in diameter. shown that PAA can be used as a versatile platform for It is noted that there is disagreement in the reported pore functional group conversion to a variety of different moi size of the parent membrane between that calculated from eties. MWCO data (8.1 nm) in the wetted state and that observed Conversion of PDMA to PAA: Functionalization in SEM micrographs (53 nm) in the dried state (FIG. 14). 10 The conversion of the PDMA moiety to PAA was per This may be attributed to the swelling ofthe PDMA domains formed via submersion of the parent membrane in an in a wetted environment. The average number ofrepeat units aqueous 6 M HCl solution. No appreciable conversion of in a linear PDMA block with molecular weight of 23.3 kDa can be approximated as NPDMA=235. In the upper limit PDMA to PAA was observed at temperatures below 60° C.; however, a high degree of conversion was observed at a that the chains are fully extended with a carbon-carbon bond 15 length (I) of 1.4 A, the PDMA chain length as a rigid rod solution temperature of 85° C., in agreement with previous (i.e., neglecting any geometrical constraints associated with reports. bond angles) LPDMA=2xN1 would be 65.8 nm. Therefore, the Deprotection of the poly(N,N-dimethylacrylamide) pore would be closed completely ifthe chains were extended groups to poly(acrylic acid) groups (PAA) was monitored by fully (131.6 nm) from both sides of the pore. However, due 20 the decreasing intensity ofthe characteristic carbonyl stretch to the balance between the enthalpy of solvent-repeat unit from the PDMA peak (labeled a in FIG. 16) and the mixing and the entropy associated with chain stretching, it simultaneous increase in the characteristic carbonyl stretch is known that the length of moderate-density, surface from PAA peak (labeled bin FIG. 16). The disappearance of grafted polymer brush chains will scale as N0.6, if the the characteristic carbonyl stretch from the PDMA demon- polymer brush is in a good solvent. 25 strates the complete conversion of the DMA group occurs Gas Diaphragm Study after 48 hours of exposure (FIG. 16). This scaling behavior changes when the polymer brush is Additionally, qualitative assignment of the ATR-FTIR confined to a nanoscale cylinder. Specifically, computational peaks (FIG. 17) indicates that no discernible degradation of models predict that, for relatively large polymers in the the PI or PS domain occurred during the deprotection stage. moderate brush density regime, the size of the polymer 30 This is supported by mechanical testing of the PDMA brush will scale with N0.8 in a good solvent. Using the functionalized and PAA-functionalized membranes (FIG. scaling from computations, the extended PDMA brush 7), which demonstrates that the toughness of the PAA within the pore would be -22 nm long. Therefore, the functionalized membrane is slightly larger than that of the effective pore diameter for the membrane in the wetted state PDMA-functionalized membrane. This increase in tough (i.e., the pore size calculated from MWCO tests) would be 35 ness may be attributed to crosslinking within the PI domains 44 nm smaller relative to the dry state [i.e., the pore size that occurs when the membrane is exposed to a strong acid determined using the SEM images and supported by gas at elevated temperatures while converting from PDMA to diaphragm cell experiments (FIG. 14)]. This would lead to PAA. an effective pore diameter in the wetted state of -9 nm, FIGS. Sb and 9b show SEM micrographs of the mem which agrees well with the transport test studies, especially 40 brane cross-section and top surface, respectively, following given the simple nature of the scaling analysis. the exposure to 6 M HCl at an elevated temperature for 48 Wetted State Study hrs. In the dried state, the structure of this converted mem In order to probe this hypothesis experimentally, the brane has the same characteristic features as that of the structure of the PI-PS-PD MA membrane was characterized parent membrane. Furthermore, the porosity, average pore in the solvated state by wetting the pores of the membrane 45 size, and pore density on the surface of the PAA-lined with the hydrophilic ionic liquid, 1,3-dimethylimidazolium membrane were estimated, and their values were found to be bis(trifluoromethyl)sulfonylimide ([mmim] [Tf2N]). within 4% of the values reported for the parent membrane. Because the vapor pressure of [mmim] [Tf2N] approaches When the PAA brushes that line the pore wall are solvated zero, its evaporation rate in the vacuum environment of the by [mmim] [Tf2N] (FIG. 15b), no pores are visible on the SEM is negligible, which enables the conformation of 50 top surface of the PI-PS-PAA membrane. The data above solvated PDMA brushes to be observed using electron demonstrate that the PDMA block has been converted to the microscopy. In the solvated state, the PDMA brushes extend PAA block in the solid state successfully and the nanostruc toward the center of the pore reducing the effective pore ture ofthe asymmetric terpolymer membrane in the dry state diameter (FIG. 15). In some cases, it appears that the is not altered significantly by the deprotection protocol. extended PDMA chains span the pore width and form 55 Hydraulic Permeability: pH Study mushroom-like structures. This extension of the PDMA Following the conversion to PAA, the hydraulic perme brushes into the pores of the membrane also provides a ability of the membrane was determined over a pH range rationalization for the very sharp MWCO reported in FIG. between 1 and 12. These data are represented by the dia 12 despite the spread in pore sizes observed in FIG. 9. monds in FIG. 11. The permeability of the membrane 2 1 1 While the tight molecular weight cutoff of the PI-PS 60 remained low (-0.6 L m- h- bar- ) as the pH of the feed PDMA-based membrane is useful, the conversion of the solution was decreased from pH 12.0 down to 4.0. At pH 3.5, pore walls to a specific functionality will be of utility in the there was a sharp increase in permeability. As the pH was production of fouling-resistant and/or chemically selective decreased further, the permeability continued to increase and membranes. Specifically, based on the relative quality of the exceeded that of the parent membrane around pH 3.0. The casting solvents for the three blocks of the terpolymer and 65 permeability did not plateau with further decreases in pH, the difference in pore size determined between the dry and and the maximum determined permeability was over 16 L wet states, we hypothesize that the parent membrane con- m-2 h-1 bar-1 at a pH of 1.0, which is comparable to high US 10,022,679 B2 33 34 flux commercial nanofiltration and moderate flux commer using a TA Instruments DMA Q800. For the wetted film cial ultrafiltration membranes. experiments, a length of film (-25 mm by 10 mm) was The dependence of the permeability on pH is due to the clamped between the two tensile contacts. Wetted film extension and contraction ofthe PAA chains lining the walls experiments were performed using a humidification cham of the pores in the membrane. At high pH, the deprotonated 5 ber attachment at 35° C. at a relative humidity of 95% and PAA is negatively charged, which causes the PAA chains to at a stress rate of 0.5 N min-1. extend into the open pores. Because the deprotonated PAA chains contain negative charges that repel each other, the The second heating scan of DSC traces of the PI and PAA brushes extend farther into the pores of the membrane PI-PS precursor samples and the PI-PS-PDMA triblock than the neutrally-charged PDMA brushes of the parent terpolymer is shown in FIG. 18. The glass transition tem 10 membrane, which results in a lower permeability. As the perature (Tg) values for each domain in these samples solutions tested become more acidic, and pH decreases, the corresponds well with the glass transition temperature val PAA is protonated. The neutrally-charged polymer chains ues measured for equivalently-sized homopolymer analogs. are able to collapse back, in part, toward the pore wall. This increases the effective diameter ofthe pores, which results in Example 10. Partial Rejection Study higher permeabilities. 15 Molecular Weight Cutoff We have demonstrated the ability to separate molecules A molecular weight cutoff experiment after conversion of based on differences in solute size using a standard stirred PDMA to PAA was performed and resulted in the curve shown by the diamonds shown in FIG. 12. This experiment cell system. After placing the membrane in the system, the was performed in deionized water (pH=5.5) where the PAA 20 membrane was challenged with solutions containing poly chains that line the pore walls are expected to extend into the ethylene oxide (PEO) molecules ranging in molecular pores, constricting flow. The curve shows nearly complete weight from 1.1 to 10 kDa. If necessary, larger molecular rejection for solutes with characteristic radii above 1.25 nm, weights can be used to characterize pores with larger dimen and moderate rejection (-7 6%) for solutes that are 0.8 nm in sions. The hydrodynamic radii of the PEO molecules were radius. This curve has shifted to the left of the parent curve, 25 calculated using intrinsic viscosity and diffusion coefficients again suggesting that the pore size of the PAA-lined mem data. The hydrodynamic radii ranged from 0.75 to 3.0 nm. brane is smaller than the parent membrane. Percent rejection values were calculated by comparing the Based on the theory for size-selective transport, the pore concentration of PEO in the solution that permeated the diameter of the converted membrane is calculated to be 2.6 membrane to the concentration of PEO in the initial feed nm in diameter, compared to 8.1 nm for the parent mem- 30 solution. The concentration of PEO was determined using brane. This PI-PS-PAA membrane retains its high selectivity total organic carbon analysis. after deprotection and is able to perform size-selective For the PI-PS-PDMA membrane, solutes with a hydro separations for solutions containing particles with hydrody dynamic radius greater than 2.2 nm, (i.e., a 6.0 kDa PEO namic radii of -1 nm. This is in the extreme lower limit of molecule) were almost completely rejected. Molecules with pore sizes for membranes based on block polymers; in fact, 35 hydrodynamic radii smaller than 1.2 nm (i.e., a 2.1 kDa PEO it is the smallest diameter reported for nanoporous films sample) permeate through the membrane with little (-4%) originating from block polymer templates. As such, this rejection. A 4.0 kDa PEO sample, which has a hydrody membrane architecture presents a new paradigm in block namic radius equal to 1.7 nm, was only partially rejected polymer based separations. Furthermore, the ability of tun (60% rejection). This point of datum, in conjunction with able pore functionality makes this carboxylic acid-function 40 established theories for size-selective separations, was used alized membrane analog a highly versatile and powerful to estimate the pore size of the parent membrane at 8 .1 nm platform for nanoscale separations. in diameter. These results demonstrate the ability to use a PI-PS A molecular weight cutoff experiment after conversion of PDMA triblock terpolymer, synthesized via the easily-con PDMA to PAA was performed. This experiment was per- trolled RAFT polymerization mechanism, as a templating 45 formed in deionized water (pH=5.5) where the PAA chains agent for the nanostructure of asymmetric, porous mem that line the pore walls are expected to extend into the pores, branes that are produced using the SNIPS technique. Fur constricting flow. The curve shows nearly complete rejection thermore, the PDMA block that lines the pore walls of the for the 2.1 kDa PEO sample (characteristic radii of 1.2 nm), membrane can be converted cleanly by simply soaking the and moderate rejection (-76%) for the 1.1 kDa PEO sample membrane in an HCl solution to yield PAA-lined pores. This 50 (0.8 nm in radius). Based on the theory for size-selective enables the pore functionality to be chemically-tailored transport, the pore diameter of the converted membrane is without degradation of the membrane nanostructure. Addi calculated to be 2.6 nm in diameter, compared to 8.1 nm for tionally, the high densities of well-defined pores in these the parent membrane. This PI-PS-PAA membrane retains its membranes are capable of producing size selective separa high selectivity after conversion of PDMA to PAA and is tions for solutes as small as 8 nm in the as-synthesized 55 able to perform size-selective separations for solutions con PI-PS-PDMA state and 2 nm in diameter after conversion to taining particles with hydrodynamic radii of -1 nm. the PI-PS-PAA state. The unique combination of properties The PI-PS-PAA functionalized membrane was also chal 2 2 provided by the PI-PS-PDMAmaterial enables next-genera lenged with an aqueous solution containing Mg+ and SO4 - tion membranes that meet the process demands of multiple ions, which have a hydration diameter of0.8 nm and 0.4 nm, high value separations (e.g., water purification, biopharma 60 respectively. The percent rejection ofthese ionic species was ceuticals separations) to be designed and produced in a 55%. Percent rejection values were calculated by comparing 2 2 simple and facile manner. the concentration of Mg+ and SO4 - in the solution that permeated the membrane to the concentration of Mg+ 2 and 2 2 Example 9. Mechanical Testing of Membrane Films SO4 - in the initial feed solution. The concentration of Mg+ 2 65 and SO4 - were determined using ion chromatography. Dynamic mechanical analysis (DMA) experiments of the Using a PI-PS-PDMA membrane with a lower total membrane films were performed in tensile loading mode molecular weight of about 30 kDa, and a weight fraction for US 10,022,679 B2 35 36 the three blocks of approximately 25%, 50% and 25%, terms of the functionality of the individual ingredient, the respectively, we were able to obtain smaller pore sizes of composition, or the embodiment). The term about can also less than 1 nm in diameter. modify the end-points of a recited range as discuss above in During these experiments, the feed solutions were stirred this paragraph. at 400 rpm to produce mass transfer coefficients, k, on the 5 As will be understood by the skilled artisan, all numbers, 5 1 4 order of 1.0xl0- m s- , while the water flux, Jw, during the including those expressing quantities of ingredients, prop MWCO tests was kept near ofbelow this value. This results erties such as molecular weight, reaction conditions, and so in a J,Jk value around 0.13 to 1, which is significantly lower forth, are approximations and are understood as being than the suggested limit where concentration polarization optionally modified in all instances by the term "about." becomes severe, ensuring the results are solely a function of 10 These values can vary depending upon the desired properties the ability ofthe membrane to separate solutes based on size. sought to be obtained by those skilled in the art utilizing the teachings of the descriptions herein. It is also understood Example 11. Functionalization of Membranes that such values inherently contain variability necessarily resulting from the standard deviations found in their respec- We have demonstrated the ability to convert the carbox 15 tive testing measurements. ylic acid functionality of the PAA moiety to that of an As will be understood by one skilled in the art, for any and alcohol, a cysteamine, an alkyl chain, and a sulfonic acid all purposes, particularly in terms of providing a written functionality through simple coupling reactions. In particu description, all ranges recited herein also encompass any and lar, a small molecule of structure NH2-R (where R is the all possible sub-ranges and combinations of sub-ranges specific chemical functionality described above). This broad 20 thereof, as well as the individual values making up the range, platform, which can be used either as a solid state or liquid particularly integer values. A recited range (e.g., weight reaction, is amenable to any other R functionality due to the percentages) includes each specific value, integer, decimal, robustness and high driving force associated with the con or identity within the range. Any listed range can be easily densation reaction between an amine and a carboxylic acid. recognized as sufficiently describing and enabling the same 25 range being broken down into at least equal halves, thirds, Definitions quarters, fifths, or tenths. As a non-limiting example, each range discussed herein can be readily broken down into a The following definitions are included to provide a clear lower third, middle third and upper third, etc. As will also be and consistent understanding ofthe specification and claims. understood by one skilled in the art, all language such as "up As used herein, the recited terms have the following mean 30 to", "at least", "greater than", "less than", "more than", "or ings. All other terms and phrases used in this specification more", and the like, include the number recited and such have their ordinary meanings as one of skill in the art would terms refer to ranges that can be subsequently broken down understand. into sub-ranges as discussed above. In the same manner, all References in the specification to "one embodiment", "an ratios recited herein also include all sub-ratios falling within embodiment", etc., indicate that the embodiment described 35 the broader ratio. Accordingly, specific values recited for may include a particular aspect, feature, structure, moiety, or radicals, substituents, and ranges, are for illustration only; characteristic, but not every embodiment necessarily they do not exclude other defined values or other values includes that aspect, feature, structure, moiety, or character within defined ranges for radicals and substituents. istic. Moreover, such phrases may, but do not necessarily, One skilled in the art will also readily recognize that refer to the same embodiment referred to in other portions of 40 where members are grouped together in a common manner, the specification. Further, when a particular aspect, feature, such as in a Markush group, the invention encompasses not structure, moiety, or characteristic is described in connection only the entire group listed as a whole, but each member of with an embodiment, it is within the knowledge of one the group individually and all possible subgroups of the skilled in the art to affect or connect such aspect, feature, main group. Additionally, for all purposes, the invention structure, moiety, or characteristic with other embodiments, 45 encompasses not only the main group, but also the main whether or not explicitly described. group absent one or more of the group members. The The singular forms "a," "an," and "the" include plural invention therefore envisages the explicit exclusion of any reference unless the context clearly dictates otherwise. It is one or more of members of a recited group. Accordingly, further noted that the claims may be drafted to exclude any provisos may apply to any of the disclosed categories or optional element. As such, this statement is intended to serve 50 embodiments whereby any one or more of the recited as antecedent basis for the use of exclusive terminology, elements, species, or embodiments, may be excluded from such as "solely," "only," and the like, in connection with any such categories or embodiments, for example, for use in an element described herein, and/or the recitation of claim explicit negative limitation. elements or use of "negative" limitations. The term "contacting" refers to the act of touching, The term "and/or" means any one of the items, any 55 making contact, or of bringing to immediate or close prox combination of the items, or all of the items with which this imity, including at the cellular or molecular level, for term is associated. The phrase "one or more" is readily example, to bring about a physiological reaction, a chemical understood by one of skill in the art, particularly when read reaction, or a physical change, e.g., in a solution, in a in context of its usage. reaction mixture, in vitro, or in vivo. The term "about" can refer to a variation off±10% of the 60 An "effective amount" refers to an amount effective to value specified. For example, "about 50" percent can in bring about a recited or desired effect, such as an amount some embodiments carry a variation from 45 to 55 percent. necessary to form products in a reaction mixture. Determi For integer ranges, the term "about" can include one or two nation ofan effective amount is typically within the capacity integers greater than and/or less than a recited integer at each ofpersons skilled in the art, especially in light ofthe detailed end ofthe range. Unless indicated otherwise herein, the term 65 disclosure provided herein. The term "effective amount" is "about" is intended to include values (e.g., weight percent intended to include an amount of a compound or reagent ages, proximate to the recited range that are equivalent in described herein, or an amount of a combination of com- US 10,022,679 B2 37 38 pounds or reagents described herein, e.g., that is effective to pores characterized by an average pore diameter of less than form products in a reaction mixture. Thus, an "effective 5 nm, wherein the multiblock copolymer is a block terpoly amount" generally means an amount that provides the mer selected from the group consisting of polyisoprene-b- desired effect. polystyrene-b-poly(N,N-dimethylacrylamide) [PI-PS- The term "nanostructured" means any structural feature 5 PDMA], polyisoprene-b-polystyrene-b-poly(tert- measured on a nanoscale. For example, the pore size of the butylmethacrylate) [PI-PS-PtBMA], poly(isoprene)-b- membranes of the present invention are measured in nano polystyrene )-b-poly( (4-vinyl)pyridine ), poly(isoprene)-b meters or fractions thereof. Hence, the membranes of the poly( styrene )-b-poly((2-vinyl) pyridine), poly(isoprene)-b - present invention are nanostructured in this respect. poly(styrene )-b-poly(ethylene oxide), poly(isoprene )-b-poly The term "microporous" refers to the porosity of the 10 (styrene b-poly(methyl methacrylate), poly(isoprene)-b support layer of the membranes or films of the present poly(styrene )-b-poly(acrylic acid), poly(isoprene )-b-poly invention. (styrene)-b-poly( dimethyl ethyl amino ethyl methacrylate), The term "nanoporous" refers to the porosity of the surface active layer ofthe membranes or films ofthe present poly(isoprene )-b-poly( styrene )-b-poly(hydroxystyrene ), poly(isoprene-b-poly(a-methyl styrene)-b-poly(( 4-vinyl) invention, which have pores sizes that are characteristically 15 less than 100 nm, or less than 10 nm or less than 5 nm. In pyridine), poly(isoprene)-b-poly( a-methyl styrene )-b-poly some embodiments they are less than one nanometer. ((2-vinyl) pyridine), poly(isoprene )-b-poly(a-methyl sty The terms "ultrafiltration" refers to filtration using a rene)-b-poly( ethylene oxide), poly(isoprene )-b-poly(a medium fine enough to retain colloidal particles, viruses, or methyl styrene)-b-poly(methyl methacrylate), poly large molecules. Nanofiltration refers to membrane filtration 20 (isoprene)-b-poly( a-methyl styrene )-b-poly(acrylic acid), based method that uses nanometer sized cylindrical through poly(isoprene )-b-poly( a-methyl styrene )-b-poly( dimethyl pores that pass through the membrane at a 90°. Nanofiltra ethyl amino ethyl methacrylate), poly (butadiene)-b-poly tion membranes have pore sizes from 1-10 nanometers, (styrene)-b-poly( (4-vinyl)pyridine ), poly(butadiene )-b-poly smaller than that used in microfiltration and ultrafiltration, (styrene)-b-poly( (2-vinyl) pyridine), poly(butadiene )-b-poly but just larger than that in reverse osmosis. 25 (styrene)-b-poly( ethylene oxide), poly(butadiene )-b-poly The term "selectivity" refers to a measure of how well a (styrene)-b-poly(methyl methacrylate), poly(butadiene)-b membrane can distinguish between two different types of poly( styrene )-b-poly(acrylic acid), poly(butadiene )-b-poly matter, such as the capability to selectively allow passage (styrene)-b-poly( dimethyl ethyl amino ethyl methacrylate), through the membrane of one or more types of matter while poly(butadiene)-b-poly(styrene )-b-poly(hydroxystyrene), selectively disallowing passage of different one or more 30 poly(butadiene)-b-poly( a-methyl styrene)-b-poly(( 4-vinyl) types of matter from passing through the membrane. pyridine), poly(butadiene )-b-poly( a-methyl styrene )-b-poly The term "selective layer" or "active selective layer" ((2-vinyl) pyridine), poly(butadiene)-b-poly( a-methyl sty refers to the upper layer of the membranes or films of the rene)-b-poly( ethylene oxide), poly(butadiene )-b-poly(a present invention, which have a nanoporous structure and methyl styrene)-b-poly(methyl methacrylate), poly give the membrane its selectivity. 35 (butadiene )-b-poly( a-methyl styrene)-b-poly(acrylic acid), The term "gutter ( or porous) layer" refers to the micropo and poly(butadiene )-b-poly( a-methyl styrene)-b-poly( dim rous support layer formed beneath the nanoporous active ethylethyl amino ethyl methacrylate). selective layer according to the methods described herein. In 2. The multiblock copolymer membrane of claim 1, contrast to the selective layer, the gutter layer does affect the wherein the average pore diameter of the nanoporous active selectivity ofthe membrane. Its main function is typically to 40 selective layer is less than 1 nm. add support and/or stability to the membrane structure. 3. The multiblock copolymer membrane of claim 1, wherein the multiblock copolymer is selected from the EQUIVALENTS AND SCOPE group consisting of polyisoprene-b-polystyrene-b-poly(N, N-dimethy la cry!amide) [PI-PS-PD MA], polyisoprene-b- Specific ingredients and proportions are for illustrative 45 polystyrene-b-poly(tert-butylmethacrylate) [PI-PS-Pt- purposes. Ingredients may be exchanged for suitable equiva BMA], poly(isoprene )-b-poly(styrene)-b-poly(( 4-vinyl) lents and proportions may be varied, according to the desired pyridine), poly(isoprene )-b-poly(styrene)-b-poly((2-vinyl) properties of the dosage form of interest. pyridine), poly(isoprene)-b-poly(styrene )-b-poly( acrylic While specific embodiments have been described above acid), poly(isoprene)-b-poly(styrene )-b-poly( dimethylethyl with reference to the disclosed embodiments and examples, 50 amino ethyl methacrylate ), poly(isoprene)-b-poly(styrene ) such embodiments are only illustrative and do not limit the b-poly(hydroxystyrene), poly(isoprene )-b-poly(a-methyl scope of the invention. Changes and modifications can be styrene )-b-poly(acrylic acid), poly(butadiene )-b-poly(sty made in accordance with ordinary skill in the art without rene)-b-poly(( 4-vinyl)pyridine), poly(butadiene )-b-poly departing from the invention in its broader aspects as defined (styrene)-b-poly( (2-vinyl) pyridine), poly(butadiene )-b-poly in the following claims. 55 (styrene)-b-poly( ethylene oxide), poly(butadiene )-b-poly All publications, patents, and patent documents are incor (styrene)-b-poly(methyl methacrylate), poly(butadiene)-b porated by reference herein, as though individually incor poly( styrene )-b-poly(acrylic acid), poly(butadiene )-b-poly porated by reference. No limitations inconsistent with this (styrene)-b-poly( dimethyl ethyl amino ethyl methacrylate), disclosure are to be understood therefrom. The invention has poly(butadiene)-b-poly(styrene )-b-poly(hydroxystyrene) been described with reference to various specific and pre 60 and poly(butadiene)-b-poly( a-methyl styrene )-b-poly ferred embodiments and techniques. However, it should be (acrylic acid). understood that many variations and modifications may be 4. A multiblock copolymer membrane comprising a self made while remaining within the spirit and scope of the assembled nanoporous active selective layer comprising invention. pores characterized by an average pore diameter of less than What is claimed is: 65 5 nm, wherein the multiblock terpolymer is a block terpoly 1. A multiblock copolymer membrane comprising a self mer selected from the group consisting of PI-PS-PDMA and assembled nanoporous active selective layer comprising PI-PS-PtBMA. US 10,022,679 B2 39 40 5. A device comprising the multiblock copolymer mem prises a terpolymer, and the terpolymer comprises polyiso brane of claim 1. prene-b-polystyrene-b-poly(N,N-dimethylacrylamide) [PI 6. The multiblock copolymer membrane of claim 1, PS-PD MA], polyisoprene-b-polystyrene-b-poly(tert- wherein the membrane has been chemically functionalized butylmethacrylate) [PI-PS-PtBMA], poly(isoprene )-b-poly with a moiety selected from the group consisting of an 5 (styrene)-b-poly( (4-vinyl)pyridine ), poly(isoprene )-b-poly alc?hol, hydroxyl, carbonyl, aldehyde, thiol, ketone, acyl (styrene)-b-poly((2-vinyl) pyridine), poly(isoprene )-b-poly halide, carbonate, carboxylate, carboxylic acid, ester, (styrene)-b-poly( ethylene oxide), poly(isoprene )-b-poly methoxy, hydroperoxide, peroxide, ether, hemiacetal, (styrene)-b-poly(methyl methacrylate), poly(isoprene)-b hemiketal, acetal, ketal, acetal, orthoester, heterocycle, poly(styrene )-b-poly(acrylic acid), poly(isoprene )-b-poly orthocarbonate ester, amide, amine, imine, imide, azide, 10 (styrene)-b-poly( dimethyl ethyl amino ethyl methacrylate) cyanate, nitrate, nitrile, nitrite, nitro compound, nitroso poly()soprene )-b-poly( styrene )-b-poly(hydroxystyrene ), ' compound, pyridine, pyridine derivative, thiol, sulfide, thio poly(1soprene )-b-poly( a-methyl styrene)-b-poly(( 4-vinyl) ether, disulfide, sulfoxide, sulfone, sulfinic acid, sulfonic pyridine), poly(isoprene)-b-poly( a-methyl styrene )-b-poly acid, thiocyanate, thione, thiol, phosphine, phosphane, phos ((2-vinyl) pyridine), poly(isoprene )-b-poly(a-methyl sty- phonic acid, phosphate, phosphodiester, boronic acid 15 rene)-b-poly( ethylene oxide), poly(isoprene )-b-poly(a boronic ester, bonnie acid, borinic ester, carboxylic acid: methyl styrene)-b-poly(methyl methacrylate), poly alkyl group, and any combination thereof. (isop~ene )-b-poly(a-methyl styrene )-b-poly(acrylic acid), 7. A method for separating, purifying, filtering or concen poly(1soprene )-b-poly( a-methyl styrene )-b-poly( dimethyl trating a liquid solution, comprising contacting the mem ethyl amino ethyl methacrylate), poly (butadiene)-b-poly brane of claim 1 with the liquid solution. 20 (styrene)-b-poly(( 4-vinyl)pyridine ), poly(butadiene )-b-poly 8. The multiblock copolymer membrane of claim 1 (styrene)-b-poly( (2-vinyl) pyridine), poly(butadiene )-b-poly wherein the membrane is an organic membrane comprisin~ (styrene)-b-poly( ethylene oxide), poly(butadiene )-b-poly a nanoporous active selective layer, wherein the nanoporous (styrene)-b-poly(methyl methacrylate), poly(butadiene)-b active selective layer comprises a plurality of pores, the poly( styrene )-b-poly(acrylic acid), poly(butadiene )-b-poly pores characterized by: 25 (styrene)-b-poly( dimethyl ethyl amino ethyl methacrylate), (i) substantially uniform pore diameters ofless than 5 nm; poly(butad)ene)-b-poly(styrene )-b-poly(hydroxystyrene), and poly(butad1ene )-b-poly(a-methyl styrene)-b-poly(( 4-vinyl) (ii) substantially uniform pore orientations which are pyridine), poly(butadiene )-b-poly( a-methyl styrene )-b-poly approximately perpendicular to surfaces of the mem ((2-vinyl) pyridine), poly(butadiene)-b-poly( a-methyl sty- brane. 30 rene)-b-poly( ethylene oxide), poly(butadiene )-b-poly(a 9. The organic membrane of claim 8, wherein the pores methy~ styrene)-b-poly(methyl methacrylate), poly are characterized by substantially uniform pore diameters of (butad1ene )-b-poly( a-methyl styrene)-b-poly(acrylic acid), less than 1 nm. or poly(butadiene)-b-poly( a-methyl styrene)-b-poly( dim 10. A device comprising the organic membrane of claim ethylethyl amino ethyl methacrylate). 8. 35 17. The nanostructured membrane of claim 16 wherein 11. A method for separating, purifying, filtering or con the terpolymer comprises polyisoprene-b-poly;tyrene-b centrating a liquid solution, comprising contacting the poly(N,N-di methyl acrylamide) [PI-PS-PDMA], polyiso organic membrane of claim 8 with the liquid solution. prene-b-polystyrene-b-poly(tert-buty lmethacrylate) [PI-PS 12. A method for forming the multiblock copolymer PtBMA], poly(isoprene )-b-poly(styrene)-b-poly(( 4-vinyl) membrane of claim 1, the method comprising the steps of: 40 pyridine), poly(isoprene )-b-poly(styrene)-b-poly((2-vinyl) a) synthesizing a self-assembled A-B-C multiblock copo pyridine), poly(isoprene)-b-poly(styrene )-b-poly( acrylic lymer; and acid), poly(isoprene)-b-poly(styrene )-b-poly( dimethylethyl b) fabricating a nano structured membrane from the self amino ethyl methacrylate ), poly(isoprene)-b-poly(styrene ) assembled A-B-C multiblock copolymer using a self b-poly(hydroxystyrene), poly(isoprene )-b-poly(a-methyl assembly and non-solvent induced phase separation. 45 styrene )-b-poly(acrylic acid), poly(butadiene )-b-poly(sty 13. The method of claim 12, wherein the synthesizing the rene)-b-poly(( 4-vinyl)pyridine), poly(butadiene )-b-poly self-assembled A-B-C multiblock copolymer is carried out (styrene)-b-poly( (2-vinyl) pyridine), poly(butadiene )-b-poly through a controlled reversible addition-fragmentation chain (styrene)-b-poly( ethylene oxide), poly(butadiene )-b-poly transfer polymerization mechanism. (styrene)-b-poly(methyl methacrylate), poly(butadiene)-b - 14. The method of claim 12, wherein the nanostructured 50 poly( styrene )-b-poly(acrylic acid), poly(butadiene )-b-poly membrane is characterized by an average pore diameter of (styrene)-b-poly( dimethyl ethyl amino ethyl methacrylate), about 0.5-3 nm. poly(butad)ene)-b-poly(styrene )-b-poly(hydroxystyrene), or 15. A nanostructured membrane of a self-assembled poly(butad1ene )-b-poly(a-methyl styrene)-b-poly( acrylic A-B-C multiblock copolymer, wherein the copolymer com acid). prises a terpolymer, and the terpolymer comprises polyiso- 55 18. The method of claim 12 wherein the multiblock prene-b-polystyrene-b-poly(N,N-dimethylacrylamide) [PI copolymer comprises a terpolymer that comprises polyiso PS-PD MA] or polyisoprene-b-polystyrene-b-poly(tert prene-b-polystyrene-b-poly(N,N-dimethylacrylamide) [PI butylmethacrylate) [PI-PS-PtBMA]. PS-PD MA] or polyisoprene-b-polystyrene-b-poly(tert-bu 16. A nanostructured membrane of a self-assembled tylmethacrylate) [PI-PS-PtBMA]. A-B-C multiblock copolymer, wherein the copolymer com- * * * * *