己二酸/无水硫酸钙晶须改性PP的等温结晶动力学

通过差示扫描量热(DSC)仪分析了己二酸(AA)和无水硫酸钙晶须(ACSW)复配改性聚丙烯(PP)的等温结晶行为,用偏光显微镜(PLM)观察了AA/ACSW复配改性PP的晶体形貌。DSC分析结果表明,随着结晶温度升高,半结晶时间和最大结晶时间增加,半结晶速率降低;与纯PP相比,ACSW和AA/ACSW复合改性都能使PP的结晶时间降低,结晶效率增加,说明ACSW和AA/ACSW对PP具有异相成核作用,并且AA/ACSW复合改性PP对提高PP的结晶性能有更好的效果,此外ACSW改性PP的等温结晶活化能最低。对改性PP的PLM的观察说明ACSW对PP具有异相成核作用,而AA/ACSW对PP的β晶成核具有协同促进作用。

Isothermal Crystallization Kinetics of Adipic Acid and Calcium Sulfate Whiskers Modified Polypropylene

The isothermal crystallization behaviors of polypropylene (PP) modified with compound nucleating agent composed of adipic acid (AA) and calcium sulfate whiskers (ACSW) were studied by differential scanning calorimeter (DSC),and the crystal morphology of PP modified by AA / ACSW was investigated by means of polarized optical microscope (PLM). DSC results show that with the increase of crystallization temperature,the half crystallization time and maximum crystallization time increase and the half crystallization rate decreases,compare with pure PP,the time of crystallization of which the addition of ACSW and the com-pound nucleating agent AA/ACSW in PP are shortened,and its crystallization kinetic rate of PP is increased,which indicate the ACSW and AA/ACSW play a role of heterogeneous nucleating agent in PP and increase the crystallization rate of PP,and AA/ACSW would be better on the crystallization rate of PP,and ACSW modified PP has the lowest activation energy. PLM results show that ACSW has heterogeneous nucleation effect in modified PP,and AA/ACSW has synergistic effect in β nucleating of PP.