Synthesis of aromatic polyethers by cation‐radical polymerization

Abstract

w : This paper discusses the synthesis of aromatic polyethers including poly(ether sulfone)s, poly(ether ether ketone)s, fully aromatic polyethers and polyarylenes by the cation-radical polymerization (Scholl reaction) of bisaryl monomers. The polymerizability of various monomers is discussed with respect to the effects of the monomer structure on the reactivity of both the monomers and of the cation-radical growing species. Examples are provided for the synthesis of polymers of unique structure by the cation-radical polymerization reactions. The cation-radical polymerization reactions have been studied under a variety of experimental conditions. The oxidants used as initiators include various Lewis acids and their combinations such as FeC13. AlC13/CuCl2, AlC13/CuC1/02, AlClfleC13, FeC13:tris(3,6-dioxaheptyl)amine complex, and organic electronacceptor compounds such as 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ).This polymerization proceeds in electrophilic solvents such as nitrobenzene, methylene chloride, etc. The cation-radical polymerization initiated by a catalytic amount of oxidant is demonstrated by using vanadyl acetylacetonate as oxidant. An example in which the polymerization proceeds by both a cation-radical reaction and an electrophilic transalkylation reaction is provided by the polymerization of 2,2-bis[4-( 1 -naphthoxy)phenyl]propane initiated with FeC13.