高熔体强度聚丙烯及发泡珠粒的制备与研究

Fabrication and Investigation of High Melt Strength Polypropylene and Its Foams

使用直接聚合法制备了具有宽分子量分布的高熔体强度聚丙烯。利用反应釜浸渍法,以上述高熔体强度聚丙烯为基础树脂可以制备聚丙烯发泡珠粒。利用扫描电子显微镜和熔体强度测试仪考察了聚丙烯发泡珠粒的制备工艺及基础树脂的熔体强度对泡孔结构的影响。结果表明,与普通商业化聚丙烯如T30S相比,较高的熔体强度有利于泡孔结构的控制。

The high melt strength polypropylene( HMSPP) was produced by direct polymerization. This polypropylene contains a wide molecular weight distribution and exhibits excellent mechanical properties,especially with very high melt strength. The expanded polypropylene( EPP) beads were produced by as-produced HMSPP through autoclave-based batch process. The effects of processing conditions and melt strength on the cellular morphology of EPP were investigated by SEM and melt strength meter,respectively. Results indicated higher melt strength facilitates the control of foaming process and cellular structure compared with common commercial polypropylene such as T30 S.