聚甲基乙撑碳酸酯加工性能研究

Study on the processing properties of poly( propylene carbonate)

利用差示扫描量热分析仪、热重分析仪、电子拉力机、熔体流动速率仪和毛细管流变仪等对聚甲基乙撑碳酸酯(PPC)的热性能、力学性能和熔融流变行为进行了研究.结果表明:PPC具有较低的玻璃化转变温度(T g)和热分解温度(T d),T g和失重率5%的T d分别为31℃和211.3℃;PPC的力学性能较差,其拉伸强度和断裂伸长率分别为7.50 MPa和536.63%,熔体流动速率随温度提高而有所升高;PPC熔体为假塑性流体,其熔体表观黏度随剪切速率和温度的增加而下降.因此在PPC成型加工中可采用升高加工温度和剪切速率的方法来提高其熔体的流动性.

The thermal property, mechanical property and rheological properties of poly （ propylene carbon- ate） were studied by differential scanning calorimetry, thermo gravimetric analyzer, electronic tensile ma- chine,melt flow rate instrument and capillary rheometer, respectively. The results showed that PPC had a lower glass transition temperature （ Ts ） and thermal decomposition temperature （ Td ）, the glass transition temperature and temperatures of weight loss ratio at 5% were 31 ~C and 211.3 ~C respectively; the me- chanical properties of PPC was low, the tensile strength and elongation at break were 7.50 MPa and 536.63% respectively, the melt flow rate increased with the temperature;PPC was pseudoplastie fluid, and the melt apparent viscosity decreased with increasing shear rate and temperature. Thus, the flowability of PPC melt could be imoroved by increasing temparature and shear rate during, its preparation.