粉末浸渍长玻璃纤维增强聚丙烯的压缩模塑

采用粉末浸渍的方法制备连续玻璃纤维增强聚丙烯预浸料,经切割获得长纤维增强聚丙烯粒子,采用单螺杆挤出机挤出形成模塑料,探索了模塑料的压缩模塑成型工艺,研究了成型后材料的力学性能及其影响因素。结果表明:粉末浸渍的长纤维增强聚丙烯经压缩模塑后可获得力学性能优良的制品;随着预浸料切割长度的增大、纤维含量的增加,材料的力学性能提高;在基体聚丙烯中添加接枝极性基团的功能化聚丙烯,可改善体系的界面结合,提高材料的力学性能,但功能化聚丙烯的含量超过一定值后,材料的冲击强度有所下降;适当提高模具温度、模塑料温度及成型压力,可以提高材料的力学性能。

COMPRESSION MOLDING OF POWDER IMPREGNATING LONG GLASS FIBER REINFORCED POLYPROPYLENE

The prepreg of continuous glass fiber reinforced PP was prepared by using powder impregnation process and cut into the pellets of long fiber reinforced PP. The compression molding process of such long fiber reinforced PP was investigated. The mechanical properties and their influential factors of the products were also studied. It was found that the parts with an excellent mechanical property could be obtained after the powder impregnating long fiber reinforced PP was compression molded. With the increment in the cut length of the prepreg and fiber content, the mechanical property increased. The modification of the interfacial adhesion between glass fiber and PP by using functionalized polypropylene grafted polar group (MPP) played a significant role in improving the mechanical properties of the composites, but the impact strength decreased above a certain level of MPP. The mechanical properties would increase when increasing the molding pressure and the temperature of mould and molding compound during the compression molding processing.