Perfluorocyclobutane aromatic ether polymers. III. Synthesis and thermal stability of a thermoset polymer containing triphenylphosphine oxide

Abstract

The preparation of a novel triaryl phosphine oxide thermoset polymer con- taining the perfluorocyclobutane linkage is described. The synthetic methodology in- volves the formation of a Grignard reagent from 4-bromotrifluorovinyloxybenzene and reaction with phosphorous trichloride to form the triaryl phosphine trifluorovinyl ether monomer. Oxidation of the phosphine monomer with hydrogen peroxide in ethanol provides quantitative conversion of the phosphine to the phosphine oxide. Analysis of the thermal decomposition of the resulting polymer in both nitrogen and air indicates improvement in thermal and thermal/oxidative stability with respect to the previously reported polymer prepared from 1,1,1-tris(4-trifluorovinyloxy)phenyl ethane. Differ- ences in thermal and thermal/oxidative performance still exist, indicating that oxida- tive processes contribute to the polymer decomposition in air. q 1998 John Wiley & Sons,