β晶型成核剂增韧改性聚丙烯及其共混物的力学性能与结晶行为

STUDY ON MECHANICAL PROPERTIES AND CRYSTALLIZATION BEHAVIOR OF POLYPROPYLENE AND THEIR BLENDING TOUGHENED BY β CRYSTALLINE FORM NUCLEATION AGENT

研究了β晶型成核剂对PPH、PPR和PPH/PPR/PPB力学性能的影响,并用偏光显微镜、示差扫描量热仪(DSC)和广角X射线衍射法(W AXD)对它们的结晶形态和行为进行了研究。结果表明,添加β晶型成核剂后,PP晶型由α晶型向β晶型转变,材料韧性提高。β晶型成核剂可使PPH冲击强度提高一倍以上,使PPR提高40%,对PPH/PPR/PPB三元共混体系也可提高40%左右,并且成核剂的加入并未使原有聚合物的屈服强度、弯曲强度下降,同时伸长率也有明显提高。

The influence of β crystalline form nucleation agent on the mechanical properties of PPH, PPR and PPH/PPR/PPB has been studied. In addition, Crystallization behavior has been investigated by polarizing microscope, DSC and wide angle X-ray diffraction spectrum. The result shows that the a crystalline form of PP is transformed to β crystalline form and the toughening effect of material is enhanced by adding β crystalline form nucleation agent. The Izod notched impact strength of PPH, PPR and PPH/PPR/PPB is separately increased by 100%, 40% and 40%. Further more their elongation at break improves obviously without the decrease of tensile strength and bending strength.