Polyarylene polyethers with pendant vinyl groups and process for

Abstract

A method for the synthesis of polyarylene polyether (PAPE) oligomers with pendant vinyl groups is presented. Aromatic polyether sulfone (APS) and poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) backbones are used for specific examples. Terminal vinyl groups may also be provided on the APS by forming the .alpha., .omega.-di(benzyl)APS before the first step of a synthesis to form pendant groups which step involves the chloromethylation of APS and PPO to provide oligomers with chloromethyl groups. PPO containing bromomethyl groups was obtained by radical bromination of the PPO methyl groups. Both chloromethylated and bromomethylated starting materials are converted to their phosphonium salts, and then subjected to a phase transfer catalyzed Wittig reaction to provide the pendant vinyl groups. An APS containing pendant ethynyl groups is prepared by bromination of the APS with pendant vinyl groups, followed by a phase transfer catalyzed dehydrobromination. Differential scanning calorimetry analysis of the thermal curing of the oligomers containing pendant vinyl groups, and, ethynyl groups, showed that the curing reaction is much faster for the former. The resulting network polymers were flexible when the starting oligomer contained pendant vinyl groups, and very rigid when it contained pendant ethynyl groups.