APPLICATION OF THE TIME-TEMPERATURE SUPERPOSITION PRINCIPLE TO THE SHEAR AND UNIAXIAL ELONGATIONAL PLOW FOR POLYMER-INORGANIC PARTICLE COMPOSITE MELT

Dynamic viscoelasticity, steady state shear viscosity and transient uniaxial elongational viscosity of a polystyrene/ whisker composite melt were measured in the temperature range from 140 degrees C to 250 degrees C. We applied the time-temperature superposition principle to shear and elongational data. The shift factor alpha(T) was independent of the whisker content and the deformation style. The time-temperature superposition principle was applicable to the linear region of the uniaxial elongational viscosity for the composite melts. The strain rate dependence of the non-linear intensity indicated that the superposition principle is also applicable to the non-linear region of uniaxial elongational viscosity. In the linear region, the transient elongational viscosity for the composites was found to be very close to three times the shear viscosity.