Abstract: Polycarbonate (PC) and self-made copolyester (PPET) modified by 1,2-propylene glycol were used as raw materials to prepare PC/PPET alloys by melt blending, and their rheological behaviors were studied by a capillary extrusion rheometer. The results indicated that the rheological experiment could not be implemented in the temperature of 240~255 ℃ due to the poor fluidity of PC. However, the PC/PPET alloys exhibited a good flowing property, indicating that the addition of PPET improved the fluidity of PC and thus made it processable at lower temperatures. The PC/PPET alloys present a pseudoplastic fluid in the above temperature range, and a decrease in viscous-flow activation energy in the beginning and then tended to increase with increasing PPET content. When the mass ratio of PC/PPET was set to 4/1 and 1/4, the temperature dependency of viscosity was more significant for the alloys, and the elevation of temperature was a suitable means to enhance the fluidity of the alloys.

Key words: polycarbonate, 1, 2-propylene glycol modifying copolyester, alloy, rheological behavior