间规立构聚丙烯非等温结晶行为研究

Nonisothermal Crystallization Behavior of Syndiotactic Polypropylene

使用DSC对间规立构聚丙烯 (sPP)和等规聚丙烯 (iPP)的非等温结晶行为进行了研究。发现间规聚丙烯具有与等规聚丙烯不同的结晶结构。修正的Avrami方程和Ozawa方程对非等温结晶过程处理得到的结晶动力学参数表明 :两种聚丙烯非等温结晶过程中的成核和生长机理不同 ;由于立构规整性的差异 。

Nonisothermal crystallization behavior of a syndiotactic polypropylene sample and an isotatic polypropylene counterpart were studied by differential scanning calorimetry(DSC) at different scanning rates. It was found that the crystalline structure of sPP was different from that of iPP. The kinetic parameters of crystallization, obtained from the corrected Avrami equation and Ozawa equation for sPP and iPP samples crystallized nonisothermally at various cooling rates, suggested that there were different nucleation and growth mechanisms existing between sPP and iPP samples. Because of the lower tacticity of sPP molecular chains, it had a lower rate of crystallization and a much lower degree of crystallinity, compared with those of iPP.