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Ring-Opening Approaches to Functional Renewable Polymers

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Ring-Opening Approaches to Functional Renewable Polymers RING-OPENING APPROACHES TO FUNCTIONAL RENEWABLE POLYMERS Geng Hua Doctoral Thesis, 2018 KTH Royal Institute of Technology Department of Fibre and Polymer Technology Polymer Technology SE-100 44 Stockholm, Sweden Copyright © 2018 Geng Hua All rights reserved Paper II © 2018 American Chemical Society Paper III © 2016 American Chemical Society Paper IV © 2017 Wiley-VCH TRITA-CBH-FOU-2018:19 ISSN 1654-1081 ISBN 978-91-7729-781-9 Akademisk avhandling som med tillstånd av KTH i Stockholm framlägges till offentlig granskning för avläggande av teknisk doktorsexamen tisdagen den 5 juni 2018, kl. 10:00 i sal F3, KTH, Lindstedtsvägen 26, Stockholm. Avhandlingen försvaras på engelska. Fakultetsopponent: Professor Sophie M. Guillaume (Université de Rennes 1, FR) To my dearest family 斧斤以时入山林，材木不可胜用也。 《孟子·梁惠王上》 约公元前三四〇年 Harvesting trees in a sustainable way, timbers will never run out. Meng Zi · Liang Hui Wang Shang c.a. 340 B.C. ABSTRACT The design of renewable substitutes to today’s polymers is a necessary technical solution to the growing environmental concerns connected to polymeric materials. This thesis offers a vision of how polymeric materials could be designed to favor environmentally benign solutions in the different phases of a polymer’s lifespan. The choice of monomer is the initial phase in the lifespan of a polymer, and the monomers used here were either based on renewable resources or could be created by chemical recycling, i.e., biobased lactones or chemically recycled cyclic carbonates. The reaction conditions during polymerization, as the second phase of a polymer’s lifespan, were carefully optimized to be as sustainable as possible. This optimization included using safer chemicals, reducing the solvent consumption and lowering the reaction temperature to limit energy consumption. Atom-economic ring-opening reactions, both ring-opening polymerization and ring-opening aminolysis, were applied to the cyclic monomers to form polyamides and polycarbonates with tunable linear structures and polyester and polyurethane hydrogels. Applications of these polymers were exemplified by fiber- and film- forming biobased polyamides to potentially replace certain current petroleum-based products; utilizing polyester hydrogel for heavy metal ion wastewater treatment with high adsorption capacity; and polyurethane hydrogels loaded with quaternary ammonium compounds and tertiary sulfonium compounds for antibacterial applications with inhibition ratios over 99% against both Staphylococcus aureus and Escherichia coli. Reconverting the polymer back to the monomer is the last phase of the lifespan and closes the lifecycle loop. This process was realized via chemical recycling of the polycarbonate through ring-closing depolymerization, which resulted in cyclic carbonate monomeric building blocks. One of the cyclic carbonates (1-MeTMC) was polymerized again using an organic base catalyst to form a regioregular polycarbonate with Xreg~0.90. The choice of the renewable monomers, the versatility of the facile ring-opening reactions and the optimized reaction conditions together realized the construction of structurally diverse renewable polymers. These polymers are well suited to be used in more sustainable material designs, which further facilitate a “greener” future. Keywords: cyclic carbonate, ring-opening polymerization, ring-opening aminolysis, biobased, lactone, polycarbonate, polyester, polyamide, polyurethane, hydrogel, adsorbent, antibacterial SAMMANFATTNING Att designa förnybara alternativ till dagens plaster är en nödvändig teknisk lösning på de ökande utmaningar polymera material ställer på miljön. Denna avhandling erbjuder en vision över hur polymera material kan skapas på sätt som minskar miljöbelastningen, med fokus på de olika delarna av en polymers livscykel. Valet av monomer, representerar det initiala skedet av en polymers livscykel. De monomerer som har valts i denna studie har ursprung i en förnybar källa eller kan skapas genom återvinning av polymert avfall, t ex biobaserade laktoner eller kemiskt återvunna cykliska karbonater. Reaktionsbetingelserna under polymerisationen, den andra delen av en polymers livscykel, optimerades noggrant för att vara så hållbara som möjligt. Detta inkluderar att använda icketoxiska kemikalier, minska användningen av lösningsmedel och sänka reaktions- temperaturen för att minska energiåtgången. Atom-ekonomiska ringöppnings- reaktioner, både via ringöppningspolymerisation och ringöppningsaminolys, applicerades på de cykliska monomererna för att bilda en rad olika polymertyper, vilka inkluderade linjära polyamider och polykarbonater och nätverk av polyestrar och polyuretaner i form av hydrogeler. Användningsområden för materialen exemplifierades genom att skapa biobaserade polyamidfibrer och filmer som i en framtid skulle kunna ersätta våra oljebaserade produkter, polyesterbaserade hydrogeler för att avlägsna tungmetall från avloppsvatten, liksom polyuretan- baserade hydrogeler med många positiva laddade grupper, vilket ger antibakteriella egenskaper. För att undersöka ett polymert materials sista led i livscykeln återvinningen, användes kemisk återvinning genom ringslutningsdepolymerisation av polykarbonater för att skapa cykliska karbonater, och därigenom nya monomerer. En av dessa cykliska karbonatmonomerer, med ett steriskt center, polymeriserades därefter kontrollerat till en regioregulär polykarbonat. Valet av förnybara monomerer, mångsidigheten av dessa okomplicerade ring- öppningsreaktioner och de optimerade reaktionsbetingelserna möjliggjorde bildandet av en grupp förnybara och återvinningsbara polymerer med stor strukturell variation. Dessa polymerer kan anses passa väl in i strävan efter mer hållbara materialval genom hela materialens livscykel, och härigenom bidra till tekniska lösningar för en mer hållbar framtid. Nyckelord: cykliskt karbonat, ringöppningspolymerisation, ringöppningsaminolys, biobaserad, lakton, polykarbonat, polyester, polyamid, polyuretan, hydrogel, adsorbent, antibakteriell LIST OF APPENDED PAPERS This thesis is a summary of the following papers: Paper (I) Hua, G.; Franzén, J.; Odelius, K. Phosphazene-catalyzed Regioselective Ring- opening Polymerization of rac-1-Methyl Trimethylene Carbonate: Colder and Less Catalyst is Better, Manuscript Paper (II) Hua, G.; Odelius, K. Exploiting Ring-Opening Aminolysis–Condensation as a Polymerization Pathway to Structurally Diverse Biobased Polyamides. Biomacromolecules 2018, acs.biomac.8b00322. Paper (III) Hua, G.; Odelius, K. From Food Additive to High-Performance Heavy Metal Adsorbent: A Versatile and Well-Tuned Design. ACS Sustain. Chem. Eng. 2016, 4 (9), 4831–4841. Paper (IV) Hua, G.; Odelius, K. Isocyanate-Free, UV-Crosslinked Poly(Hydroxyurethane) Networks: A Sustainable Approach toward Highly Functional Antibacterial Gels. Macromol. Biosci. 2017, 17 (11), 1700190. Author contributions to the appended papers: Paper (I) All of the experimental work and data evaluation; writing a major part of the manuscript. Paper (II) All of the experimental work and data evaluation; writing a major part of the manuscript. Paper (III) All of the experimental work and data evaluation; writing a major part of the manuscript. Paper (IV) All of the experimental work and data evaluation; writing a major part of the manuscript. Scientific contributions not included in the thesis: Hua, G.; Franzén, J.; Odelius, K. One-Pot Inimer Promoted ROCP Synthesis of Branched Copolyesters Using α-Hydroxy-γ-Butyrolactone as the Branching Reagent. J. Polym. Sci. Part A Polym. Chem. 2016, 54 (13), 1908–1918. Xu, H.; Hua, G.; Odelius, K.; Hakkarainen, M. Stereocontrolled Entanglement- Directed Self-Alignment of Poly(lactic Acid) Cylindrites. Macromol. Chem. Phys. 2016, 217 (23), 2567–2575. ABBREVIATIONS AOMEC 2-Allyloxymethyl-2-ethyl-trimethylene carbonate BnOH Benzyl alcohol CFU Colony-forming unit Ð Dispersity (Mw/Mn) DBU 1,8-Diazabicyclo[5.4.0]undec-7-ene DI water Deionized water diamine-B 1,3-Bis(aminomethyl)benzene diamine-C 1,3-Byclohexanebis(methyl-amine) diamine-E 2,2’-(Ethylenedioxy)-bis(ethylamine) E. coli Escherichia coli EB Ethylene brassylate N,N′-((Ethane-1,2-diylbis(oxy))bis(ethane-2,1-diyl))- EBB bis(2,3,4,5,6-pentahydroxyhexanamide) EDS Energy-dispersive X-ray spectroscopy EDTA Ethylenediaminetetraacetic acid EDTAD Ethylenediaminetetraacetic dianhydride EG-(SH)2 2,2′-(Ethylenedioxy) diethanethiol FTIR Fourier transform infrared spectroscopy FT-Raman Fourier transform Raman spectroscopy GDL δ-Gluconolactone H-bonding Hydrogen bonding HFIP 1,1,1,3,3,3-Hexafluoro-2-propanol HH Head-to-head HT Head-to-tail HUM Hydroxyl urethane macromer MALDI-ToF Matrix-assisted laser desorption/ionization time-of-flight mass MS spectrometry MeCN Acetonitrile MeI Iodomethane Mn Number-average molecular weight Mw Weight-average molecular weight Mη Viscosity-average molecular weight NMR Nuclear magnetic resonance OD625nm Optic density at 625 nm wavelength PA Polyamide N,N′-(1,3-Phenylenebis(methylene))bis- PBP (2,3,4,5,6-pentahydroxyhexanamide) PhMe Toluene PHU Poly(hydroxyl urethane) QAC Quaternary ammonium compound qm Maximum adsorption capacity R.T. Room temperature rac-1-MeTMC rac-4-Methyl-1,3-dioxan-2-one RCD Ring-closing depolymerization ROA Ring-opening aminolysis ROAC Ring-opening aminolysis-condensation ROP Ring-opening polymerization RTIR Real-time infrared spectroscopy S. aureus Staphylococcus aureus SEC Size-exclusion chromatography SEM Scanning electron microscope TAEA Tris(2-aminoethyl)amine TBD 1,5,7-Triazabicyclo[4.4.0]dec-5-ene 1-Tert-butyl-2,2,4,4,4-pentakis-(dimethylamino)-2λ5,4λ5-
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