title: Biodegradable elastomeric networks: highly efficient cross-linking of poly(trimethylene carbonate) by gamma irradiation in the presence of pentaerythritol triacrylate.
abstract: Biodegradable elastomeric poly(trimethylene carbonate) (PTMC) networks were efficiently formed by gamma irradiating the linear polymer in the presence of pentaerythritol triacrylate (PETA). The properties of networks formed upon irradiation of PTMC films containing (0, 1, 5 wt %) PETA as a cross-linking aid were evaluated. The gel contents and network densities increased with increasing PETA contents, irradiation dose, and initial polymer molecular weights. At a dose of 25 kGy, networks with gel fractions up to 0.96 could be obtained. The networks were noncytotoxic, had elastic moduli below 10.7 MPa and high tensile strengths of up to 37.7 MPa. The incorporation of PETA also improved the resistance to creep and to tear propagation significantly, resulting in permanent set values that were as low as 0.9% strain and tear strengths up to 9.3 ± 2.0 N/mm. Furthermore, the enzymatic erosion rates of the networks could be decreased from 12.0 ± 2.9 to 3.0 ± 1.6 μm/day. These biodegradable elastomeric PTMC networks may be utilized in a broad range of medical applications.
authors.affiliation: MIRA Institute for Biomedical Technology and Technical Medicine and Department of Polymer Chemistry and Biomaterials, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands.
authors.forename: Erhan
authors.initials: E
authors.lastname: Bat
authors.forename: Jan
authors.initials: J
authors.lastname: Feijen
authors.forename: Dirk W
authors.initials: DW
authors.lastname: Grijpma
mesh_terms: D000179:Acrylates / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D003432:Cross-Linking Reagents / Q000737:chemistry* / Q000528:radiation effects; D004146:Dioxanes / Q000737:chemistry* / Q000528:radiation effects; D020724:Elastomers / Q000138:chemical synthesis* / Q000737:chemistry / Q000633:toxicity; D005720:Gamma Rays; D055595:Mechanical Phenomena / Q000528:radiation effects; D051379:Mice; D008970:Molecular Weight; D041681:NIH 3T3 Cells; D011108:Polymers / Q000737:chemistry* / Q000528:radiation effects; D011409:Propylene Glycols / Q000737:chemistry*; D011829:Radiation Dosage; D013696:Temperature
chemical_list: D000179:Acrylates; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D004146:Dioxanes; D020724:Elastomers; D011108:Polymers; D011409:Propylene Glycols; C059299:polytrimethylene carbonate; C027992:pentaerythrityl triacrylate