成型工艺对超临界二氧化碳发泡HMSPP结构与性能的影响

摘要

High-melt-strength polypropylene (HMSPP) foaming material with low cost and good performance by using supercritical CO2 as physical foaming agent with a self-made device was studied.The effects of foaming temperature,foaming pressure and holding time on the macroscopic properties and cell structure of HMSPP foaming material were studied.The results show that when foaming temperature is 141 ℃,The foaming ratio is 10 and the minimum apparent density is 0.09 g/cm3;when foaming pressure reaches 10 MPa,the foaming ratio is 16.63 and the apparent density is 0.054 g/cm3;the effect of holding time is not very significant,the predetermined pressure time of 30 min can meet the requirements of the experiment.Conversely,too long time will reduce the performance of foam material.%采用釜压发泡方法,以高熔体强度聚丙烯(HMSPP)为原料,超临界二氧化碳(scCO2)为物理发泡剂,研究不同温度、压力、保压时间对发泡材料泡孔结构的影响.结果表明,发泡温度对发泡体系的影响最为明显,在141℃时材料的发泡效果最好,发泡倍率为10倍,表观密度最小为0.09 g/cm3;压力为10 MPa时材料的发泡效果较好,发泡倍率为16.63倍,表观密度为0.054g/cm3;保压时间对材料发泡效果影响则不是很显著,预定的30 min保压时间可以完全满足本实验要求,时间过长反而会降低发泡材料的综合性能.