Amphiphilic conetworks. II. Novel two-step synthesis of poly[2-(dimethylamino)ethyl methacrylate]-polyisobutylene, poly(N-isopropylacrylamide)-polyisobutylene, and poly(N,N-dimethylacrylamide)-polyisobutylene hydrogels

摘要

Amphiphilic polymer conetworks consisting of hydrophilic poly[2-(dimethylamino)ethyl methacrylate], poly(N-isopropylacrylamide), or poly(N,N-dimethylacrylamide) and hydrophobic polyisobutylene chains were synthesized with a novel two-step procedure. In the first step, a methacrylate-multifunctional polyisobutylene crosslinker was prepared by the cationic copolymerization of isobutylene with 3-isopropenyl-alpha,alpha-dimethylbenzyl isocyanate. In the second step, the methacrylate-multifunctional polyisobutylene crosslinker, with a number-average molecular weight of 8200 and an average functionality of approximately 4 per chain, was copolymerized radically with 2-(dimethylamino)ethyl methacrylate, N-isopropylacrylamide, or N,N-dimethylacrylamide into transparent amphiphilic conetworks containing 42-47 mol% hydrophilic monomer. The synthesized conetworks were characterized with solid-state C-13 NMR spectroscopy and differential scanning calorimetry. The amphiphilic nature of the conetworks was proved by swelling in both water and n-heptane. (c) 2006 Wiley Periodicals, Inc.