一种各向同性低收缩率改性聚丙烯材料的研制

摘要

通过选定特定熔体流动速率共聚聚丙烯(PP)与纳米CaCO3、滑石粉、短切玻璃纤维(GF)和收缩率调节剂茂金属线性低密度聚乙烯(mPE–LLD)接枝物制备了改性PP材料,研究了各组分对改性PP水平流动方向和垂直流动方向收缩率及力学性能的影响.结果表明,纳米CaCO3及滑石粉的复合加入可减少PP水平和垂直方向收缩率差异,而mPE–LLD接枝物的加入可显著降低PP水平和垂直方向收缩率的差异.当纳米CaCO3、滑石粉、玻璃纤维和mPE–LLD接枝物质量分数分别为5%,20%,8%,5%时,所制得的改性PP水平和垂直方向收缩率分别为0.63%和0.65%,接近各向同性收缩.且所制的改性PP材料的力学性能和收缩接近于高抗冲聚苯乙烯(HIPS)水平,可替代HIPS在家电等产品上应用.%By using the selected melt index co-polypropylene,nano-CaCO3,talcum powder,chopped glass fiber and metallocene polyethylene graft copolymer which acted as conditioning agent concentration percentage,the modified polypropylene materials were prepared.The effects of above groups on the shrink rate and mechanical properties of modified polypropylene in the horizontal and vertical flowing direction were studied.The results show that the combined addition of nano-CaCO3 and talcum powder can partly reduce the difference in the shrink rate of polypropylene between the horizontal and vertical directions,while metallocene polyethylene graft copolymer can significantly reduce.When the mass fraction of nano-CaCO3,talcum powder,glass fiber and metallocene polyethylene graft copolymer is 5%,20%,8%,5%,the shrink rate of gained modified polypropylene materials in horizontal and vertical directions is 0.63% and 0.65%,close to the isotropic shrink rate,and the mechanical properties and concentration of gained modified polypropylene materials are close to those of HIPS,and the materials can replace HIPS to be used for household appliances and other products.