Poly(oxy‐1,4‐phenylene) macromonomers for polycondensation

Abstract

Abstract Macromonomers based on poly(oxy‐1,4‐phenylene) (POP) with end groups suitable for polycondensation were synthesized. In a one‐step reaction, α‐(2,5‐dimethoxyphenyl)‐ω‐bromooligo‐(oxy‐1,4‐phenylene) ( 3 ) was obtained by Ullmann reaction of 1‐bromo‐2,5‐dimethoxybenzene ( 2 ) and potassium 4‐bromophenolate ( 1 ). Ether bond cleavage with boron tribromide yields the α‐(2,5‐dihydroxyphenyl) derivative 5 , a novel type of macromonomers. Cocondensation with tert ‐butylhydroquinone and trifluoromethylterephthaloyl dichloride results in the formation of a liquid‐crystalline graft copolymer ( 7 ).