Intermolecular association of polymers through functional end-groups: Sulphate and sulphonate end-groups

Abstract

Intermolecular association of some polystyrene and poly(methyl methacrylate) (PMMA) samples bearing sulphate and/or sulphonate end-groups prepared by using the redox initiator systems K 2S 2O 8 + NaHSO 3, Na 2SO 3 + Cu 2+, NaHSO 3 + O 2 has been studied for dilute solutions in toluene, chloroform, o-dichlorobenzene, tetrahydrofuran (THF) and ethyl acetate respectively by viscometry and in toluene and THF by osmometry. Significant association of the polymers occurs in toluene, chloroform and o-dichlorobenzene in the dilute solutions used in this work. However, association is significantly reduced in chloroform containing 2% ethanol or in toluene containing 2% methanol. Tetrahydrofuran appears to be the preferred solvent for determining the molecular weights of such polymers, since association is insignificant in this solvent.