Synthesis of poly (p-phenylene) macromonomers and multiblock copolymers

Rigid-rod poly(4'-methyl-2,5-benzophenone) macromonomers were synthesized b y Ni(0) catalytic coupling of 2,5-dichloro-4'-methylbenzophenone and end-ca pping agent 4-chloro-4'-fluorobenzophenone. The macromonomers produced were labile to nucleophilic aromatic substitution. The molecular weight of poly (4'-methyl-2,5-benzophenone) was controlled by varying the amount of the en d-capping agent in the reaction mixture. Glass-transition temperatures of t he macromonomers increased with increasing molecular weight and ranged from 117 to 213 degreesC. Substitution of the macromonomer end groups was deter mined to be nearly quantitative by H-1 NMR and gel permeation chromatograph y. The polymerization of a poly(4'-methyl-2,5-benzophenone) macromonomer [n umber-average molecular weight (M-n) = 1.90 x 10(3) g/mol; polydispersity ( M-w)/M-n = 2.04] with hydroxy end-capped bisphenol A polyaryletherketone (M -n = 4.50 x 10(3) g/mol; M-w/M-n = 1.92) afforded an alternating multiblock copolymer (M-n = 1.95 x 10(4) g/mol; M-w/M-n = 6.02) that formed flexible, transparent films that could be creased without cracking. (C) 2001 John Wi ley & Sons, Inc.