PBT的增韧改性和挤出工艺对性能的影响

Toughening Modification of PBT and Effect of Extrusion Process on Properties

采用双螺杆挤出机熔融共混的方法,制备了增韧PBT材料,通过力学测试、熔融指数测试和扫描电子显微镜(SEM)等手段研究了树脂粘度、增韧剂用量和挤出工艺对材料性能的影响。结果表明:高粘PBT比低粘PBT的增韧效率更高;挤出工艺对增韧PBT的性能影响很大,其中喂料对材料的刚韧性影响很大,对流动性影响不大,而转速对材料的刚韧性影响不大,对流动性影响不大;当树脂为高粘PBT,增韧剂用量为2.0%时,最佳的挤出工艺为转速300 rpm,喂料量100 kg/h。

Toughened PBT was prepared by melt blending in twin screw extruder. To study the effects of resin viscosity, amount of toughening agent and extrusion process on properties, mechanical tests and melt flow index were conducted, and phase structure was studied through SEM. The results showed that PBT with high viscosity was easier to be toughened than that with low viscosity. Extrusion process had a great influence on properties, where feeding affected mechanical properties significantly but melt flow ability slightly, while the screw speed was the opposite. When the resin was high-viscosity and the amount of toughening agent was 2.0 %, the optimal extrusion process was screw speed with 300 rpm and feeding with 100 kg/h.