title: Isocyanate- and phosgene-free routes to polyfunctional cyclic carbonates and green polyurethanes by fixation of carbon dioxide.
abstract: The catalytic chemical fixation of carbon dioxide by carbonation of oxiranes, oxetanes, and polyols represents a very versatile green chemistry route to environmentally benign di- and polyfunctional cyclic carbonates as intermediates for the formation of non-isocyanate poly-urethane (NIPU). Two synthetic pathways lead to NIPU thermoplastics and thermosets: i) polycondensation of diacarbamates or acyclic dicarbonates with diols or diamines, respectively, and ii) polyaddition by ring-opening polymerization of di- and polyfunctional cyclic carbonates with di- and polyamines. The absence of hazardous and highly moisture-sensitive isocyanates as intermediates eliminates the need for special safety precautions, drying and handling procedures. Incorporated into polymer backbones and side chains, carbonate groups enable facile tailoring of a great variety of urethane-functional polymers. As compared with conventional polyurethanes, ring-opening polymerization of polyfunctional cyclic carbonates affords polyhydroxyurethanes with unconventional architectures including NIPUs containing carbohydrate segments. NIPU/epoxy hybrid coatings can be applied on wet surfaces and exhibit improved adhesion, thermal stability and wear resistance. Combining chemical with biological carbon dioxide fixation affords 100% bio-based NIPUs derived from plant oils, terpenes, carbohydrates, and bio polyols. Biocompatible and biodegradable NIPU as well as NIPU biocomposites hold great promise for biomedical applications.
authors: Freiburg Materials Research Center (FMF) and Institute for Macromolecular Chemistry, Stefan-Meier Strasse 31, D-79104, Freiburg, Germany.
authors: Hannes
authors: H
authors: Blattmann
authors: Maria
authors: M
authors: Fleischer
authors: Moritz
authors: M
authors: Bähr
authors: Rolf
authors: R
authors: Mülhaupt
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry; D002245:Carbon Dioxide / Q000737:chemistry*; D004852:Epoxy Compounds / Q000737:chemistry; D055772:Green Chemistry Technology; D017953:Isocyanates / Q000737:chemistry*; D010705:Phosgene / Q000737:chemistry*; D011076:Polycarboxylate Cement / Q000138:chemical synthesis / Q000737:chemistry*; D058105:Polymerization; D011140:Polyurethanes / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D004852:Epoxy Compounds; D017953:Isocyanates; D011076:Polycarboxylate Cement; D011140:Polyurethanes; D010705:Phosgene; D002245:Carbon Dioxide; C005506:polycarbonate
keywords: carbon dioxide fixation; cyclic carbonate; functional polymers; green chemistry; polyurethane