物理改性对PP成型收缩性的影响

研究了物理改性对聚丙烯(PP)成型收缩率的影响效果及其作用机理。研究表明,填充、共混、增强改性均可降低PP的成型收缩率。填充改性通过改变PP的结构状态影响PP的成型收缩率,且片状的滑石粉有较好的效果;共混改性通过使共混组分的分子链相互缠绕,改变PP的结晶从而控制PP的成型收缩率,与高密度聚乙烯相比,线性低密度聚乙烯对PP成型收缩率的影响较显著;玻璃纤维(GF)增强改性PP除了起到破坏PP的结晶度,从而影响成型收缩率外,更重要的是GF的加入限制了PP的结晶收缩。

INFLUENCE OF PHYSICAL MODIFICATION ON SHRINKAGE OF PP

The influence of physical modification on the shrinkage of PP is discussed. The result showed that filling, blending and reinforcing modification all can reduce the shrinkage of PP. In the modification of filling, the shrinkage of PP is changed by altering the configuration of PP and the sheet talcum has better effect. In the modification of blending, the shrinkage of PP is controlled by changing the crystal of polymer and the LLDPE has better effect on controlling the shrinkage of PP. In the modification of reinforcing, fiber glass affects the shrinkage of PP by destroying the crystal degree and restricting the crystal shrinkage of PP.