title: Photo-cross-linked poly(ethylene carbonate) elastomers: synthesis, in vivo degradation, and determination of in vivo degradation mechanism.
abstract: Low-molecular-weight poly(ethylene carbonate) diols of varying molecular weight were generated through catalyzed thermal degradation of high-molecular-weight poly(ethylene carbonate). These polymers were then end functionalized with acrylate groups. The resulting α,ω-diacrylates were effectively photo-cross-linked upon exposure to long-wave UV light in the presence of a photoinitiator to yield rubbery networks of low sol content. The degree of cross-linking effectively controlled the in vivo degradation rate of the networks by adherent macrophages; higher cross-link densities yielded slower degradation rates. The cross-link density did not affect the number of adherent macrophages at the elastomer/tissue interface, indicating that cross-linking affected the susceptibility of the elastomer to degradative species released by the macrophages. The reactive species likely responsible for in vivo degradation appears to be superoxide anion, as the in vivo results were in agreement with in vitro degradation via superoxide anion, while cholesterol esterase, known to degrade similar poly(alkylene carbonate)s, had no affect on elastomer degradation.
authors.affiliation: Department of Chemical Engineering, Queen's University, Kingston, ON, Canada.
authors.forename: L A
authors.initials: LA
authors.lastname: Cornacchione
authors.forename: B
authors.initials: B
authors.lastname: Qi
authors.forename: J
authors.initials: J
authors.lastname: Bianco
authors.forename: Z
authors.initials: Z
authors.lastname: Zhou
authors.forename: B G
authors.initials: BG
authors.lastname: Amsden
mesh_terms: D000818:Animals; D003432:Cross-Linking Reagents / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D020724:Elastomers / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D008264:Macrophages / Q000737:chemistry / Q000378:metabolism*; D008297:Male; D015394:Molecular Structure; D008970:Molecular Weight; D055668:Photochemical Processes; D011095:Polyethylenes / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003432:Cross-Linking Reagents; D020724:Elastomers; D011095:Polyethylenes; C039212:polyethylene carbonate