New substituted polymethylenes by free radical polymerization of bulky fumarates and their properties

The free radical polymerization of fumarates (DRFs) bearing sterically crowded ester groups was investigated. Various new monomers were synthesized and their polymerization behaviour was looked into. In bulk polymerizations at 60 degrees C initiated with 2,2'-azobisisobutyronitrile (AIBN), their polymerization reactivity depends sensitively on the structure of both alkyl ester groups. Besides the polymerization of simple alkyl fumarates, the extension to substituents bearing functional groups was explored. Functional groups have been found to be barely tolerated, successful polymerization requiring the use of particular initiators. The polymers were characterized by H-1-NMR and C-13-NMR spectroscopies, and wide-angle X-ray diffraction (WAXD), and some thermal properties were examined. (C) 2000 Elsevier Science Ltd. All rights reserved.