纳米CaCO3改性β成核聚丙烯的研究

采用经铝钛复合偶联剂处理的纳米CaCO3粒子对β成核聚丙烯（β-PP）进行改性，研究了pPP／纳米CaCO3复合材料的力学性能。结果表明，添加纳米CaCO3能够提高β-PP的综合力学性能，在纳米CaCO3用量为4％（质量分数，下同）时，冲击强度比β-PP提高了33％，是纯PP的3倍；拉伸模量、弯曲模量分别比β-PP提高了10％和15％。X射线衍射和偏光显微镜对β-PP／纳米CaCO3复合材料的结晶结构表征表明，添加纳米CaCO3可以提高β-PP的β晶含量。降低晶粒尺寸，但不会改变β-PP的束状结晶结构形态；差示扫描量热分析表明，纳米CaCO3粒子的存在降低了β-PP的结晶温度和结晶速率。

Calcium Carbonate Nanoparticles Modified Beta-nucleated Polypropylene

The beta-nucleated polypropylene was modified using calcium carbonate nanoparticles coated with aluminum and titanium complex coupling agent. The crystal structures and crystallization behavior of the composites were studied using XRD, polarizing microscope, and DSC. It showed because of the presence of calcium carbonate nanoparticles, the content of beta-crystal increased, the spherulite size decreased, the crystallization temperature and crystallization rate decreased, however, the sheaf-like crystal morphology was not affected. The mechanical properties of beta-nucleated PP were generally improved by the calcium carbonate nanoparticles. At 4 wt% loading of the calcium carbonate nanoparticles, the impact strength, tensile modulus, and flexural modulus were increased by 33 %, 10 %, and 15 %, respectively, based on neat resin.