THE EFFECT OF STAR-LIKE BRANCHING AND SOLVENT QUALITY ON INTERMOLECULAR AND INTRAMOLECULAR INTERACTION PARAMETERS OF POLYSTYRENE-SOLVENT SYSTEMS

The inter- and intramolecular interaction parameters for polystyrenes with linear and simulated star-like structures in various solvents wer e determined. Starting from experimental data for the second virial co efficient (A(2)) and intrinsic viscosity ([eta]) of linear polystyrene and from the theoretical ratios A(2,star)/A(2,lincar) and [eta](star) /[eta](lincar) the interaction parameters for f-arm star polystyrenes (with f = 2 - 18) were calculated. These parameters were studied as fu nctions of the exponent ''a'' from the Mark-Houwink equation varying t he solvents from poor to good ones. The cumulative effects of branchin g and of solvent duality yielded surface plots. The results are in goo d agreement with previous studies based on experimental data.