Journal ArticleDOI
Lipase-Catalyzed Ring-Opening Polymerization of Trimethylene Carbonate†
Kirpal S. Bisht,Yuri Y. Svirkin,Lori A. Henderson,Richard A. Gross,David L. Kaplan,Graham Swift +5 more
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Abstract:
This work was directed at extending the use of lipase-catalyzed ring-opening polymerizations to cyclic carbonate monomers. Of the seven lipases screened for bulk trimethylene carbonate (TMC) polymerization (70 °C, 120 h), Novozym-435 from Candida antarctica gave almost quantitative monomer conversion (97%) and poly(TMC) with a Mn = 15 000 (Mw/Mn = 2.2) with no apparent decarboxylation during propagation. The lipases from Pseudomonas species (AK and PS-30) and porcine pancreas (PPL) also exhibited high monomer conversions (>80%, 120 h) but gave lower molecular weight polymers with broad polydispersity. Analyses by 1H-NMR spectroscopy suggested that poly(TMC) prepared by Novozym-435-catalyzed polymerization had terminal −CH2OH functionalities at both chain ends. A monotonic increase in monomer conversion with time and the rapid increase in Mn as a function of monomer conversion for Novozym-435-catalyzed TMC bulk polymerization at 70 °C suggest that the polymerization has chain-type propagation kinetics. An ...read more
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Polymer Synthesis by In Vitro Enzyme Catalysis
TL;DR: Microbial polymers are synthesized from renewable low-cost feedstocks, and the polymerizations operate under mild process conditions with minimal environmental impact, providing products that, when disposed, can degrade to nontoxic products.
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Enzymatic polymer synthesis: an opportunity for green polymer chemistry.
Shiro Kobayashi,Akira Makino +1 more
TL;DR: Observations demonstrate that new polymeric materials are often brought about by new production methods including polymerization catalysts, as exemplified typically by the discovery of Ziegler-Natta catalyst.
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Aliphatic cyclic carbonates and spiroorthocarbonates as monomers
TL;DR: In this paper, a review of the synthesis and polymerization of aliphatic cyclic carbonates of different size and type is presented. And the mechanisms of cationic, anionic, coordination and enzymatic polymerization are discussed for obtaining polymers with well-defined structures and oligomers with reactive pendant and end groups.
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Degradable polymer microspheres for controlled drug delivery
TL;DR: This review is concerned with degradable polymers for use in controlled drug delivery with emphasis on the preparation, applications, biocompatibility, and stability of microspheres from hydrolytically degradably polymers.
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The in vivo and in vitro degradation behavior of poly(trimethylene carbonate)
TL;DR: It can be concluded that enzymatic degradation plays an important role in the surface erosion of PTMC in vivo.
References
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Journal ArticleDOI
Enzymatic Ring-Opening Polymerization of Lactones Catalyzed by Lipase
Hiroshi Uyama,Shiro Kobayashi +1 more
TL;DR: Enzymatic ring-opening polymerization of lactones was achieved by using lipase as catalyst and e-caprolactone was polymerized by Pseudomonas fluorescens lipase at 60 °C in bulk for 10 days.