Abstract
In order to improve the biocompatibility of polyurethane, a series of graft copolyurethanes (gPEU-II-VI) were prepared by using a macromonomer technique. Dihydroxy-terminated macromonomer, Mac (MPC/MMA), was prepared by radical polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and methyl methacrylate (MMA) with 2, 2′ -azobis (isobutyronitrile) (AIBN) in the presence of thioglycerol as a chain transfer agent. Polycondensation of polyethylene glycol (or polypropylene glycol) and diisocyanate was carried out in the presence of Mac (MPC/MMA) in dimethyl sulfoxide (DMSO) to give gPEU-III-VI with [η] =0.13-0.20 dL·g-1. Diisocyanates used were tolylene 2, 4-diisocyanate and 4, 4′ -diphenylmethane diisocyanate. Graft copolyurethane gPEU-II as a control was also prepared by using dihydroxy-terminated macromonomer of MMA, Mac (MMA). XPS measurements showed that MPC moieties and polyethylene segments in gPEU-III-VI were located on the surface of wet polymer films. It was found that gPEU-IIIVI suppresses the adsorption of bovine serum albumin less than gPEU-II did as the control. In cell culture test, films prepared from gPEU-III-VI showed no adhesiveness of mouse fibroblast (L-929). These findings indicate that the modification of the surface of polyurethane with MPC moieties is useful for improving biocompatibility.
