Preparation of functional poly(ether-urethane) for immobilization of humanliving cells 1. Surface graft polymerization of poly(ether-urethane) with 2-(dimethylamino)ethyl methacrylate and quaternization of grafted membrane

Functional Poly(ether-urethane) (PEU) was prepared by grafting 2-(dimethyla mino)ethylmethacrylate(DMAEM) onto the membrane surface and quaternizing th e grafted membrane. Graft polymerization was conducted by combining photo-o xidation and irradiation grafting. PEU membrane was photo-oxidized firstly in hydrogen peroxide solution and then grafted with DMAEM under UV light. T he grafted membrane was quaternized with iodomethane. The results showed th at the hydroperoxide groups content was dependent on photo-oxidization time and reached a maximum at about 8 h; degree of grafting increased with hydr operoxide groups content, irradiation time and monomer concentration. Irrad iation under UV light enhanced the graft polymerization. The grafted DMAEM could be quaternized completely. ATR-FTIR spectra, X-ray photoelectron spec troscopy, optical microscopic photographs and water absorption percent char acterized the grafted and quaternized copolymers. ATR-FTIR and XPS analysis further verified the occurrence of graft polymerization and quaternization reaction. The photographs of the grafted and quaternized membranes with a low degree of grafting consisted of regular cobblestones on the surfaces wh ile the grafted membranes with a very high degree of grafting showed minima l morphology, and the cobblestones recurred after being quaternized. Water absorption percent increased slightly with the degree of grafting and rapid ly when the grafted membrane was quaternized. (C) 2000 Elsevier Science Ltd . All rights reserved.