不同成核剂及模温对聚丙烯注塑发泡材料性能的影响

The Effect of Nucleation Agents and Mold Temperature on Properties of Injection Molded Polypropylene Foams

采用化学发泡注塑成型技术,在二次开模的条件下研究了不同成核剂及模温对聚丙烯(PP)注塑发泡材料性能(如泡孔尺寸分布、泡孔密度、皮层厚度及力学性能)的影响。结果表明:成核剂及模温的改变均会对泡孔形貌产生影响,添加成核剂和提高模温均可有效促进成核过程,增加泡孔数量。成核剂的引入对发泡PP力学性能的影响不大,而模温可以影响发泡PP的皮层厚度,进而使材料的力学性能发生变化。在泡孔结构(泡孔尺寸及其分布、泡孔数量)相近的情况下,皮层越厚材料的力学性能则越好。

The effects of nucleation agents and mold temperature on properties of injection molded polypropylene(PP) foams, including the effects on cell size distribution, cell densities, the thickness of the skin layer and mechanical properties of PP foams, were investigated using core-back injection foaming technology with chemical foaming agent. The results show that, both the nucleation agents and mold temperature can influence the cell morphologies of PP foams, and the nucleation process and cell densities can be promoted simultaneously. The addition of nucleation agents has little effect on mechanical properties of PP foams, while mold temperature can affect the skin thickness of PP foams which is related to mechanical properties. With a similar cell morphologies(cell size and its distribution, cell densities), the thickness of skin layer of PP foams has a signifi cant effect on mechanical properties of PP foams.