高发泡倍率辐射交联聚丙烯泡沫的制备

Preparation of High-expanded Radiation Crosslinked Polypropylene Foams

采用电子加速器对聚丙烯(PP)片材进行辐照交联,再通过模压发泡,获得了高发泡倍率的泡沫材料。研究了交联助剂、辐照气氛及吸收剂量对辐照交联PP凝胶含量的影响,以及PP发泡的工艺条件。通过对泡沫表观密度以及泡孔形貌的分析,考察了交联PP的凝胶含量、发泡剂用量、发泡温度、模压压力以及模压时间等条件对PP发泡效果的影响。结果表明,当凝胶分数为35%～55%、发泡剂用量为30%、发泡温度210～260℃、模压压力10～12MPa、模压时间7～15 min时,可制得具有闭孔结构、泡孔均匀、表观密度为0.032 g/cm3的泡沫材料。

Polypropylene sheets were irradiated and crosslinked by electron accelerator,though molding and foaming,the high expanded foaming material was prepared.The effects of crosslinking additive,irradiation atmosphere and absorbing dose on gel content of the irradiation crosslinking PP and the foaming technology of PP were investigated.The effects of gel content of crosslinked PP,amount of foaming agent,foaming temperature,molding pressure and time on foaming efficiency were studied by analyzing the apparent density and cell morphology.The results showed that when gel fraction was 35%-55%,blowing agent was 30%,molding temperature was 210-240 ℃,the pressure was 10-12 MPa for 7-15 min,the foamed material with closed cell structure and even cell was prepared,and the apparent density of the foam was 0.032 g/cm3.