Controlled and Living Polymerizations: Methods and Materials
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Topological Polymer Chemistry
Prog. Polym. Sci. 27 +2002) 1069±1122 www.elsevier.com/locate/ppolysci Topological polymer chemistry Yasuyuki Tezuka*, Hideaki Oike1 Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan Received 4 December 2001; revised 15 February 2002; accepted 16 February 2002 Abstract Recent developments in designing non-linear polymer topologies comprising cyclic and branched segments are reviewed. Thus ®rst, a systematic classi®cation of non-linear polymer topologies is presented by reference to constitutional isomerism in a series of alkanes +CnH2n12), monocycloalkanes +CnH2n) and polycycloalkanes +CnH2n22,CnH2n24, etc.). A special emphasis is placed on constitutional isomerism as well as stereoisomerism occurring uniquely in such non-linear polymer molecules as cyclics, knots and catenanes. Secondly, a novel strategy based on an `electrostatic self-assembly and covalent ®xation' process is described to realize a variety of topologically unique polymer architectures. Those include monocyclic and polycyclic polymers, polymeric topological isomers, cyclic macromonomers and cyclic telechelics +kyklo-telechelics) and `a ring with a branch' topology polymers, as well as such model branched polymers as star polymers and polymacromonomers. In this process, new telechelic polymer precursors having a moderately strained cyclic onium salt group as single or multiple end groups carrying multifunctional carboxylate counteranions have been prepared through an ion- exchange reaction. The unique electrostatic self-assembly directed by these polymer precursors, particularly in a diluted organic solution, is transformed into the covalent product by the heat treatment of the polymer precursor, causing the ring-opening reaction to produce a variety of topologically unique, non-linear polymer architectures in high ef®ciency. -
Cationic/Anionic/Living Polymerizationspolymerizations Objectives
Chemical Engineering 160/260 Polymer Science and Engineering LectureLecture 1919 -- Cationic/Anionic/LivingCationic/Anionic/Living PolymerizationsPolymerizations Objectives • To compare and contrast cationic and anionic mechanisms for polymerization, with reference to free radical polymerization as the most common route to high polymer. • To emphasize the importance of stabilization of the charged reactive center on the growing chain. • To develop expressions for the average degree of polymerization and molecular weight distribution for anionic polymerization. • To introduce the concept of a “living” polymerization. • To emphasize the utility of anionic and living polymerizations in the synthesis of block copolymers. Effect of Substituents on Chain Mechanism Monomer Radical Anionic Cationic Hetero. Ethylene + - + + Propylene - - - + 1-Butene - - - + Isobutene - - + - 1,3-Butadiene + + - + Isoprene + + - + Styrene + + + + Vinyl chloride + - - + Acrylonitrile + + - + Methacrylate + + - + esters • Almost all substituents allow resonance delocalization. • Electron-withdrawing substituents lead to anionic mechanism. • Electron-donating substituents lead to cationic mechanism. Overview of Ionic Polymerization: Selectivity • Ionic polymerizations are more selective than radical processes due to strict requirements for stabilization of ionic propagating species. Cationic: limited to monomers with electron- donating groups R1 | RO- _ CH =CH- CH =C 2 2 | R2 Anionic: limited to monomers with electron- withdrawing groups O O || || _ -C≡N -C-OR -C- Overview of Ionic Chain Polymerization: Counterions • A counterion is present in both anionic and cationic polymerizations, yielding ion pairs, not free ions. Cationic:~~~C+(X-) Anionic: ~~~C-(M+) • There will be similar effects of counterion and solvent on the rate, stereochemistry, and copolymerization for both cationic and anionic polymerization. • Formation of relatively stable ions is necessary in order to have reasonable lifetimes for propagation. -
WO 2015/179628 Al 26 November 2015 (26.11.2015) P O P C T
(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date WO 2015/179628 Al 26 November 2015 (26.11.2015) P O P C T (51) International Patent Classification: (81) Designated States (unless otherwise indicated, for every C08F 210/16 (2006.01) kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, (21) International Application Number: BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM, PCT/US20 15/03 1952 DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, (22) International Filing Date: HN, HR, HU, ID, IL, IN, IR, IS, JP, KE, KG, KN, KP, KR, 2 1 May 2015 (21 .05.2015) KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, (25) Filing Language: English PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, (26) Publication Language: English SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (30) Priority Data: 14/284,689 22 May 2014 (22.05.2014) US (84) Designated States (unless otherwise indicated, for every kind of regional protection available): ARIPO (BW, GH, (71) Applicant: CHEVRON PHILLIPS CHEMICAL COM¬ GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, PANY LP [US/US]; 10001 Six Pines Drive, The Wood TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, lands, TX 77380 (US). -
Examining the Technology for a Sustainable Environment Grant Program
Examining the Technology for a Sustainable Environment Grant Program An Interactive Qualifying Project Report Submitted to the Faculty of WORCESTER POLYTECHNIC INSTIUTE In partial fulfillment of the requirements for the Degree of Bachelor of Science Submitted to: Professor James Demetry Professor Joseph Petruccelli Worcester Polytechnic Institute: Washington, D.C. Project Center By: Eddie Diaz _____________________ Melissa Hinton _____________________ Mark Stevenson _____________________ December 13, 2004 In Cooperation with the Environmental Protection Agency Diana Bauer, Ph.D April Richards, PE National Center of National Center of Environmental Research Environmental Research Environmental Protection Environmental Protection Agency Agency Washington, DC 20005 Washington, DC 20005 This report is submitted in partial fulfillment of the degree requirements of Worcester Polytechnic Institute. The views and opinions expressed herein are those of the authors and do not necessarily reflect the positions or opinions of the Environmental Protection Agency or Worcester Polytechnic Institute. Abstract This project was performed with the support of the Environmental Protection Agency and involved the examination of the Technology for a Sustainable Environment (TSE) grants program. We selected ten researchers funded by the TSE program, interviewed them, and reviewed their research in terms of qualitative and quantitative academic, industrial, and potential environmental impacts. For each of the ten researchers, we wove this information together -
Acrylamide, Sodium Acrylate Polymer (Cas No
ACRYLAMIDE/SODIUM ACRYLATE COPOLYMER (CAS NO. 25085‐02‐3) ACRYLAMIDE, SODIUM ACRYLATE POLYMER (CAS NO. 25987‐30‐8) 2‐PROPENOIC ACID, POTASSIUM SALT, POLYMER WITH 2‐PROPENAMIDE (CAS NO. 31212‐13‐2) SILICONE BASED EMULSION NEUTRALISED POLYACRYLIC BASED STABILIZER (NO CAS NO.) This group contains a sodium salt of a polymer consisting of acrylic acid, methacrylic acid or one of their simple esters and three similar polymers. They are expected to have similar environmental concerns and have consequently been assessed as a group. Information provided in this dossier is based on acrylamide/sodium acrylate copolymer (CAS No. 25085‐02‐3). This dossier on acrylamide/sodium acrylate copolymer and similar polymers presents the most critical studies pertinent to the risk assessment of these polymers in their use in drilling muds. This dossier does not represent an exhaustive or critical review of all available data. Where possible, study quality was evaluated using the Klimisch scoring system (Klimisch et al., 1997). Screening Assessment Conclusion – Acrylamide/sodium acrylate copolymer, acrylamide, sodium acrylate polymer and 2‐propenoic acid, potassium salt, polymer with 2‐propenamide are polymers of low concern. Therefore, these polymers and the other similar polymer in this group are classified as tier 1 chemicals and require a hazard assessment only. 1. BACKGROUND Acrylamide/sodium acrylate copolymer is a sodium salt of a polymer consisting of acrylic acid, methacrylic acid or one of their simple esters. Acrylates are a family of polymers which are a type of vinyl polymer. Synthetic chemicals used in the manufacture of plastics, paint formulations and other products. Acrylate copolymer is a general term for copolymers of two or more monomers consisting of acrylic acid, methacrylic acid or one of their simple esters. -
High Temperature, Living Polymerization of Ethylene by a Sterically-Demanding Nickel(II) Α-Diimine Catalyst
polymers Article High Temperature, Living Polymerization of Ethylene by a Sterically-Demanding Nickel(II) α-Diimine Catalyst Lauren A. Brown, W. Curtis Anderson Jr., Nolan E. Mitchell, Kevin R. Gmernicki and Brian K. Long * ID Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA; [email protected] (L.A.B.); [email protected] (W.C.A.J.); [email protected] (N.E.M.); [email protected] (K.R.G.) * Correspondence: [email protected]; Tel.: +1-865-974-5664 Received: 15 December 2017; Accepted: 27 December 2017; Published: 2 January 2018 Abstract: Catalysts that employ late transition-metals, namely Ni and Pd, have been extensively studied for olefin polymerizations, co-polymerizations, and for the synthesis of advanced polymeric structures, such as block co-polymers. Unfortunately, many of these catalysts often exhibit poor thermal stability and/or non-living polymerization behavior that limits their ability to access tailored polymer structures. Due to this, the development of catalysts that display controlled/living behavior at elevated temperatures is vital. In this manuscript, we describe a Ni α-diimine complex that is capable of polymerizing ethylene in a living manner at temperatures as high as 75 ◦C, which is one of the highest temperatures reported for the living polymerization of ethylene by a late transition metal-based catalyst. Furthermore, we will demonstrate that this catalyst’s living behavior is not dependent on the presence of monomer, and that it can be exploited to access polyethylene-based block co-polymers. Keywords: polyethylene; living polymerization; nickel α-diimine; catalysis 1. Introduction Controlled/living polymerizations offer a precise means by which polymer structure, co-monomer incorporation levels, and even regio- and stereoselectivity can be tailored [1–7]. -
Free-Radical Photopolymerization of Acrylonitrile Grafted Onto Epoxidized Natural Rubber
polymers Article Free-Radical Photopolymerization of Acrylonitrile Grafted onto Epoxidized Natural Rubber Rawdah Whba 1,2, Mohd Sukor Su’ait 3, Lee Tian Khoon 1,* , Salmiah Ibrahim 4, Nor Sabirin Mohamed 4 and Azizan Ahmad 1,5,* 1 Department of Chemical Sciences, Faculty of Sciences and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia; [email protected] 2 Department of Chemistry, Faculty of Applied Sciences, Taiz University, Taiz 6803, Yemen 3 Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia; [email protected] 4 Centre for Foundation Studies in Science, University of Malaya, Kuala Lumpur 50603, Malaysia; [email protected] (S.I.); [email protected] (N.S.M.) 5 Research Center for Quantum Engineering Design, Faculty of Science and Technology, Universitas Airlangga, Surabaya 60286, Indonesia * Correspondence: [email protected] (L.T.K.); [email protected] (A.A.); Tel.: +60-12-7279286 (L.T.K.); +60-19-3666576 (A.A.) Abstract: The exploitation of epoxidized natural rubber (ENR) in electrochemical applications is approaching its limits because of its poor thermo-mechanical properties. These properties could be improved by chemical and/or physical modification, including grafting and/or crosslinking techniques. In this work, acrylonitrile (ACN) has been successfully grafted onto ENR- 25 by a radical photopolymerization technique. The effect of (ACN to ENR) mole ratios on chemical structure Citation: Whba, R.; Su’ait, M.S.; Tian and interaction, thermo-mechanical behaviour and that related to the viscoelastic properties of the Khoon, L.; Ibrahim, S.; Mohamed, polymer was investigated. The existence of the –C≡N functional group at the end-product of ACN-g- N.S.; Ahmad, A. -
Synthesis of Polypeptides by Ring-Opening Polymerization of A-Amino Acid N-Carboxyanhydrides
Top Curr Chem (2011) DOI: 10.1007/128_2011_173 # Springer-Verlag Berlin Heidelberg 2011 Synthesis of Polypeptides by Ring-Opening Polymerization of a-Amino Acid N-Carboxyanhydrides Jianjun Cheng and Timothy J. Deming Abstract This chapter summarizes methods for the synthesis of polypeptides by ring-opening polymerization. Traditional and recently improved methods used to polymerize a-amino acid N-carboxyanhydrides (NCAs) for the synthesis of homo- polypeptides are described. Use of these methods and strategies for the preparation of block copolypeptides and side-chain-functionalized polypeptides are also pre- sented, as well as an analysis of the synthetic scope of different approaches. Finally, issues relating to obtaining highly functional polypeptides in pure form are detailed. Keywords Amino acid Á Block copolymer Á N-Carboxyanhydride Á Polymerization Á Polypeptide Contents 1 Introduction 2 Polypeptide Synthesis Using NCAs 2.1 Conventional Methods 2.2 Transition Metal Initiators 2.3 Recent Developments 3 Copolypeptide and Functional Polypeptide Synthesis via NCA Polymerization 3.1 Block Copolypeptides 3.2 Side-Chain-Functionalized Polypeptides 4 Polypeptide Deprotection and Purification 5 Conclusions and Future Prospects References J. Cheng Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Champaign, IL 61801, USA T.J. Deming (*) Department of Bioengineering, University of California, Los Angeles, CA 90095, USA e-mail: [email protected] J. Cheng and T.J. Deming Abbreviations AM Activated -
Dispersity Control in Atom Transfer Radical Polymerizations Through Addition of Phenyl Hydrazine
Polymer Chemistry Dispersity Control in Atom Transfer Radical Polymerizations through Addition of Phenyl Hydrazine Journal: Polymer Chemistry Manuscript ID PY-ART-01-2018-000033.R1 Article Type: Paper Date Submitted by the Author: 04-May-2018 Complete List of Authors: Yadav, Vivek; University of Houston Hashmi, Nairah; University of Houston Ding, Wenyue; University of Houston Li, Tzu-Han; University of Houston Mahanthappa, Mahesh; University of Minnesota, Department of Chemical Engineering & Materials Science; University of Wisconsin–Madison, Department of Chemistry Conrad, Jacinta; University of Houston, Robertson, Megan; University of Houston, Chemical and Biomolecular Engineering Page 1 of 32 Polymer Chemistry Dispersity Control in Atom Transfer Radical Polymerizations through Addition of Phenyl Hydrazine Vivek Yadav,a Nairah Hashmi,a Wenyue Ding,a Tzu-Han Li,c Mahesh K. Mahanthappa,d Jacinta C. Conrad,*a and Megan L. Robertson*a,b a Department of Chemical and Biomolecular Engineering University of Houston, Houston, TX 77204-4004 b Department of Chemistry University of Houston, Houston, TX 77204-4004 c Materials Engineering Program University of Houston, Houston, TX 77204-4004d Department of Chemical Engineering and Materials Science University of Minnesota, Minneapolis, MN 55455 *Email: [email protected], [email protected] †Electronic Supplementary Information available online. 1 Polymer Chemistry Page 2 of 32 Abstract Molar mass dispersity in polymers affects a wide range of important material properties, yet there are few synthetic methods that systematically generate unimodal distributions with specifically tailored dispersities. Here, we describe a general method for tuning the dispersity of polymers synthesized via atom transfer radical polymerization (ATRP). Addition of varying amounts of phenyl hydrazine (PH) to the ATRP of tert-butyl acrylate led to significant deviations in the reaction kinetics, yielding poly(tert-butyl acrylate) with dispersities Đ = 1.08 – 1.80. -
7: Source-Based Nomenclature for Copolymers (1985)
7: Source-Based Nomenclature for Copolymers (1985) PREAMBLE Copolymers have gained considerable importance both in scientific research and in industrial applications. A consistent and clearly defined system for naming these polymers would, therefore, be of great utility. The nomenclature proposals presented here are intended to serve this purpose by setting forth a system for designating the types of monomeric-unit sequence arrangements in copolymer molecules. In principle, a comprehensive structure-based system of naming copolymers would be desirable. However, such a system presupposes a knowledge of the structural identity of all the constitutional units as well as their sequential arrangements within the polymer molecules; this information is rarely available for the synthetic polymers encountered in practice. For this reason, the proposals presented in this Report embody an essentially source-based nomenclature system. Application of this system should not discourage the use of structure-based nomenclature whenever the copolymer structure is fully known and is amenable to treatment by the rules for single-strand polymers [1, 2]. Further, an attempt has been made to maintain consistency, as far as possible, with the abbreviated nomenclature of synthetic polypeptides published by the IUPAC-IUB Commission on Biochemical Nomenclature [3]. It is intended that the present nomenclature system supersede the previous recommendations published in 1952 [4]. BASIC CONCEPT The nomenclature system presented here is designed for copolymers. By definition, copolymers are polymers that are derived from more than one species of monomer [5]. Various classes of copolymers are discussed, which are based on the characteristic sequence arrangements of the monomeric units within the copolymer molecules. -
Aim: to Prepare Block Copolymers of Methyl Methacrylate (MMA) and Styrene
Conducting A Reversible-Deactivation Radical Polymerization (RDRP) Aim: To Prepare Block Copolymers of Methyl Methacrylate (MMA) and Styrene. Polymers are ubiquitous in the modern world. They provide tremendous value because the chemical and physical properties of these materials are determined by the monomers that are used to put them together. One of the most powerful methods to construct polymers is radical-chain polymerization and this method is used in the commercial synthesis of polymers everyday. Methyl methacrylate is polymerized to form poly(methyl methacrylate) (PMMA) which is also known as acrylic glass or Plexiglas (about 2 billion pounds per year in the US). This material is lightweight, strong and durable. The polymer chains are rigid due to the tetrasubstituted carbon atom in the polymer backbone and they have excellent optical clarity. As a consequence, these materials are used in aircraft windows, glasses, skylights, signs and displays. Polystyrene (PS), which can also be synthesized from radical chain polymerization, has found extensive use as a material (also approximately 2 billion pounds per year in the US). One of the forms of PS, Styrofoam, is used extensively to make disposable cups, thermal insulation, and cushion for packaging. Scheme 1. Radical polymerization of methyl methacrylate or styrene. While there are extensive uses for these polymers, when synthesizing any material using a free-radical polymerization, samples are obtained with limited control over molecular weight and molecular weight distribution. New methods have been developed directly at Carnegie Mellon (https://www.cmu.edu/maty/) which lead to improved control in this process. This new method is a reversible-deactivation of the polymerization reaction where highly reactive radicals toggle back and forth between an active state, where the polymer chain is growing, and a dormant state, where the polymer chain is capped (Scheme 2). -
1 050929 Quiz 1 Introduction to Polymers 1) in Class We Discussed
050929 Quiz 1 Introduction to Polymers 1) In class we discussed a hierarchical categorization of the terms: macromolecule, polymer and plastics, in that plastics are polymers and macromolecules and polymers are macromolecules; but all macromolecules are not polymers and all polymers are not plastics. a) Give an example of a macromolecule that is not a polymer. b) Give an example of a polymer that is not a plastic. c) Define polymer. d) Define plastic. e) Define macromolecule. 2) In class we observed a simulation of a small polymer chain of 40 flexible steps. The chain was observed to explore configurational space. a) Explain what the phrase "explore configurational space" means. b) Consider the two ends of the chain to be tethered with a separation distance of about 6 extended steps. If temperature were increased would the chain ends push apart or pull together the tether points? Explain why. c) If one chain end is fixed in Cartesian space at x = 0, what are the limits on the x-axis for the other chain end as it explores configurational space? d) What is the average value of the position on the x-axis? dγ 3) Polymer melts are processed at high rates of strain, , in an extruder, injection molder, or dt calander. a) Sketch a typical plot of polymer viscosity versus rate of strain on a log-log plot showing the power-law region and the Newtonian plateau at low rates of strain. b) Explain using this plot why polymers are processed at high rates of strain. c) Using your own words propose a molecular model that could explain shear thinning in polymers.