C-13-NMR investigation of the blockiness of poly(para-xylylene alpha-tetrahydrothiophenium halide) polyelectrolyte formation

C-13-NMR spectroscopy was used to study the formation of the water-soluble polyelectrolyte precursor of poly(para-phenylene vinylene), poly(para-xylyl ene alpha -tetrahydrothiophenium bromide), under the conditions of the sulf onium precursor route. 1,4-Bis(tetrahydrothiophenio-C-13-methyl)benzene dib romide was copolymerized with 1,4-bis(tetrahydrothiopheniomethyl)-2-nitrobe nzene dibromide, 2,5-bis(tetrahydrothiopheniomethyl)thiophene dibromide, 1, 4-bis(tetrahydrothiopheniomethyl)-2,5-dichlorobenzene dibromide, and 1,4-bi s(tetrahydrothiopheniomethyl)-2,5-oxybenzene dichloride in water at reduced temperature. NMR analysis of the resultant crude reaction products showed a behavior varying from presumed random polymerization to blocky polymeriza tion, depending on the substituents of the co-monomer.