轻质碳酸钙／聚丙烯共混物中聚丙烯β－晶的成核结晶研究

Studies on the Nucleation and Crystallization of β-Crystal of Polypropylene in Light Calcium Carbonate/Polypropylene Blends.

用Ｘ射线衍射和差示扫描量热法研究了轻质碳酸钙／聚丙烯共混物（Ｌ－ＣａＣＯ３／ＰＰ）中ＰＰβ－晶的成核结晶现象，发现ＰＰβ－晶的成核结晶与ＰＰ的来源和Ｌ－ＣａＣＯ３在共混物中的含量有关，铝酸酯偶联剂对共混体系的ＰＰβ－晶的成核结晶有显著的增强作用．分析认为共混物中ＰＰβ－晶的成核结晶现象是ＰＰ中存在的某些杂质（主要是催化剂残余物）与Ｌ－ＣａＣＯ３组成的复合成核剂作用的结果，而铝酸酯是这种复合成核剂的一种促进剂．

The phenomenon of nucleation and crystallization of β-crystal of polypropylene(PP)in light calcium carbonate(L-CaCO3)/PP blends was studied by X-ray diffraction and differential scanning calorimetry. It was found that the nucleation and crystallization of βcrystal of PP in L-CaCO3/PP blends was dependent on the PP samples used. Aluminate coupling agents have a synergistic effect on the nucleation and crystallization of β-crystal of PP in L-CaCO3/PP blends. It is believed tl1at the phenomenon of nucleation and crystallization of β-crystal of PP in L-CaCO3/PP blends is the result of the action of a complex nucleation agent composed of residues of the catalyst used for polymerization of propylene and L-CaCO3,and the aluminates may be considered as promoters in the complex nucleation agent.