MICELLE FORMATION AND POLYISOBUTYLENE SOLUBILIZATION BY BLOCK-POLY(ETHYLENE-CO-BUTYLENE)-BLOCK-POLYSTYRENE BLOCK-COPOLYMERS

Thermodynamics of micellization and the structure of micelles formed b y block-poly(ethylene-co-bulylene)-block-polystyrene block copolymers were studied. A molar mass influence on the aggregation number of mice lles was found. The lower the molar mass, the higher the micelle aggre gation number. The solubilization of polyisobutylene by micelles of th ese copolymers in methyl isobutyl ketone was also examined. The satura tion concentrations of polyisobutylene solubilized by different block copolymers in methyl isobutyl ketone were determined by laser light sc attering. The solubility curves found were linear and dependent on the molar mass of the polyisobutylene solubilized and the copolymer. The logarithm of the maximum amount of polyisobutylene solubilized by mass unity of the triblock copolymer varies linearly with the logarithm of the molar mass of the polyisobutylene. This variation is hardly depen dent on the copolymer molar mass and strongly dependent on the type of block copolymer.