RELATION BETWEEN SOME RHEOLOGICAL PROPERTIES OF POLYISOBUTYLENE SOLUTIONS AND THEIR MODE OF PREPARATION

Results are presented of a rheological study of solutions of high mole cular weight polyisobutylene in decalin in steady and oscillatory shea r flows. We have examined the influence of the preparation mode and th e purity of the solvent on the viscosity, the dynamic modulus and the relaxation times. For one solution, the effect of temperature on the m aterial functions is represented. The experimental data are fitted by the Cross model, and the Cox-Merz rule holds for dynamic and steady da ta for low and intermediate shear rates.