聚丙烯/超细丁苯胶粉/纳米碳酸钙三元复合材料的制备与性能

采用喷雾干燥方法得到丁苯橡胶／纳米碳酸钙复合粉末橡胶(RPS)，探讨了RPS中苯甲酸钠用量以及丁苯橡胶与纳米碳酸钙质量比对聚丙烯(PP)力学性能、耐热性和结晶性能的影响。结果表明，苯甲酸钠最佳用量为丁苯橡胶和纳米碳酸钙总用量的10％；随着纳米碳酸钙用量的增加，体系中分散相粒径减小，结晶速率加快，材料的韧性、刚性和耐热性能提高。RPS对于不同熔体流动指数的PP具有不同的增韧增强效果。熔体流动指数越小，越有利于RPS在PP中的分散，体系韧性越高。此外。动态流变学研究表明，PP／RPS三元复合材料的熔体流变行为与纯PP类似，RPS的加入增加了PP的黏度．流动性能变差。

Preparation and properties of polypropylene/ultra-fine styrene-butadiene powdered rubber/nano-CaCO3 ternary composites

A special complex powdered rubber (RPS) was prepared by spray drying styrene-butadiene rubber latex together with nano-CaCO 3 slurry. The effect of the sodium benzoate content in RPS and the mass ratio of styrene-butadiene rubber and nano-CaCO 3 on the mechanical and heat resistance properties, crystallization properties of polypropylene(PP) was investigated. It was found that the increase of the fraction of nano-CaCO 3 particles and the introduction of sodium benzoate into PP ternary system led to the decrease of the dispersion phase particle size within PP matrix and the increase of crystallization rate, and consequently resulted in the improvement of impact resistance, stiffness and heat resistance of the PP composites. The effect of RPS complex powdered rubber on the mechanical and heat resistance properties of different PP was also investigated. It was found that the lower the melt index of the PP was, the more easily the blending shear force could be transferred to the rubber particles, then the better dispersion of RPS in PP. Studies on rheological properties of PP/RPS showed that introduction of RPS in PP led to the increase of melt viscosity of PP.