Novel Copolymers of 4-Fluorostyrene. 6. Dialkoxy Ring-Substituted 2-Phenyl-1,1-dicyanoethylenes

Abstract

fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70 • C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1 H and 13 C-NMR. The order of relative reactivity (1/r 1 ) for the monomers is 2,6-(CH 3 O) 2 (2.8) > 2,5-(CH 3 O) 2 (2.5) > 2,3-(CH 3 O) 2 (2.1) > 3,5-(CH 3 O) 2 (1.8) > 3,4-(CH 3 O) 2 (0.9) > 2,4-(CH 3 O) 2 (0.7). High T g of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 250-400 • C range with residue, which then decomposition in 400-800 • C range.