无机填料粒径对口模拉伸PP/CaCO_(3)复合材料性能的影响  

Effect of Inorganic Filler Particle Size on Properties of Die-drawn PP/CaCO_(3) Composites

作　　者：禹世康 陈轲 薛平[1] 刘鸣飞 羊群 YU Shikang;CHEN Ke;XUE Ping;LIU Mingfei;YANG Qun(Institute of Plastic Machinery and Engineering,Beijing University of Chemical Technology,Beijing 100029,China)

机构地区：[1]北京化工大学塑料机械及塑料工程研究所,北京100029

出　　处：《塑料工业》2022年第8期89-94,共6页China Plastics Industry

基　　金：中央高校基本科研业务费专项资金资助(ZY2204)。

摘　　要：通过口模拉伸技术制备了高模、高强、轻质的聚丙烯/碳酸钙(PP/CaCO_(3))复合材料,分析了无机填料CaCO_(3)粒径对口模拉伸制品微观结构、热性能、密度、力学性能的影响。X射线衍射(XRD)和差示扫描量热仪(DSC)结果表明口模拉伸过程中存在拉伸应力诱导熔融再结晶机制,粒径较小的PP/CaCO_(3)复合材料制品的结晶度越高,结晶结构更完善。扫描电镜(SEM)结果表明,CaCO_(3)颗粒附近形成有沿拉伸方向的细长微孔,PP分子链段与片晶沿拉伸方向取向形成微纤结构,且CaCO_(3)粒径越小,微纤排列越致密。口模拉伸后材料的密度降低,粒径越大密度降低效果越显著。微纤结构的形成提高了材料的力学性能,当填料粒径最小为1 250目时,PP/CaCO_(3)复合材料制品的拉伸强度和弯曲模量分别为112.9 MPa和5.05 GPa,其密度仅为0.87 g/cm~3,材料的力学性能表现最佳。High modulus, high strength and light weight polypropylene/calcium carbonate(PP/CaCO_(3)) composites were prepared by die drawing technology, the influence of inorganic filler size on micro-structure, thermal properties, density and mechanical properties of the die-drawn PP/CaCO_(3) products were analyzed.The X-ray diffraction(XRD)and differential scanning calorimeter(DSC)results show that there is tensile stress induced re-crystallization during die drawing process, the PP/CaCO_(3) composites product with smaller particle size has higher crystallinity and more perfect crystal structure.The scanning electron microscope(SEM)results show that there are slender micro-voids along the drawing direction near the CaCO_(3) particles, and the PP molecular and lamellae are oriented along the drawing direction to form microfiber structure, and the smaller the CaCO_(3) particle size, the denser the microfiber structure arrange.The density of the composites decreases after die drawing, and the larger the particle size, the more significantly the density reduces.The formation of microfiber structure improves the mechanical properties of the composites.When the minimum filler particle size is 1 250 mesh, the tensile strength and the flexural modulus of the die-drawn PP/CaCO_(3) composite product are 112.9 MPa and 5.05 GPa, respectively, the density is only 0.87 g/cm~3,the mechanical properties of the composites are the best.

关 键 词：口模拉伸 聚丙烯/碳酸钙复合材料 取向 微纤 微孔 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]