利用型腔体积可控注塑发泡装置制备微发泡聚丙烯(PP)/粉末橡胶复合材料,通过橡胶粒子的分散性以及复合材料的结晶行为,研究不同橡胶粒子对聚丙烯复合材料发泡行为和力学性能的影响。结果表明:橡胶粒子的加入使微发泡聚丙烯材料的泡孔分布细密而均匀,微发泡聚丙烯/马来酸酐接枝聚丙烯/粉末丁腈胶(PP/PP-MAH/NBR)复合材料的发泡质量较理想,其泡孔密度和尺寸分别为7.64×106个/cm3,29.78μm;综合泡孔结构和力学性能,微发泡聚丙烯/聚丙烯接枝马来酸酐/粉末羧端基丁腈胶(PP/PP-MAH/CNBR)复合材料的力学性能最优,与纯PP比较其冲击强度提升了2.2倍,拉伸强度仅仅降低了26%,是理想的微发泡复合材料。
Polypropylene/rubber powders composites with different kinds of rubber powders were foamed by injection molding machine equipped with volume-adjustable cavity.The effect of dispersity of rubber powders and crystallization behavior of composites on the foaming behavior and mechanical properties was investigated.The results show that the addition of rubber powders can improve the cell structure of foamed PP with fine and uniform cell distribution.And cell density and size of PP/PPMAH/NBR foams are 7.64×106cell/cm3 and 29.78μm respectively,which are the best among these foams.Combining cell structures with mechanical properties,notch impact strength of PP/PP-MAH/CNBR composites increases approximately by 2.2times while tensile strength is reduced just by 26%compared with those of the pure PP.This indicates that PP/PP-MAH/CNBR composites are ideal foamed materials.