SYNTHESIS AND SOME PROPERTIES OF GRAFT-COPOLYMERS WITH UNIFORM POLYOXYETHYLENE SIDE-CHAINS

Graft copolymers with uniform polyoxyethylene (PEO) side chains were synthesized by transesterification of poly(methyl,tert-butyl fumarate) (PMtBF) or poly(methyl,tert-butyl fumarate-co-styrene) poly(MtBF-co-St) with potassium alkoxide of PEO monoether. The grafting efficiency increased with enhanced alkoxide reactivity, but the main factor in the ester exchange proved to be the structure of the backbone. This effect was ascribed to the thermodynamic incompatibility between fumaric polymers and PEO. The polymers were characterized by spectral methods, GPC, and DSC. In THF the graft copolymers comprising a polyfumarate backbone with PEO side chains eluted at higher elution volumes than did the backbone homopolymers. In benzene their intrinsic viscosities were lower than those of the backbones. In aqueous eluents, micelles were detected, and their aggregation number depended on the composition of the copolymer and the eluent.