口模拉伸过程PP/CaCO_(3)复合材料结构演变及机理  

Structural evolution and mechanism of PP/CaCO_(3) composites during die drawing

作　　者：禹世康 陈轲 薛平[1] 贾明印[1] 蔡建臣[2] YU Shikang;CHEN Ke;XUE Ping;JIA Mingyin;CAI Jianchen(Institute of Plastic Machinery and Engineering,Beijing University of Chemical Technology,Beijing 100029,China;School of Mechanical and Electrical Engineering,Quzhou University,Quzhou 324000,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 [2]衢州学院机电工程学院,浙江衢州324000

出　　处：《中国塑料》2022年第10期1-6,共6页China Plastics

基　　金：中央高校基本科研业务费专项资金资助(ZY2204)。

摘　　要：利用口模拉伸法制备了轻质、高强、高模的聚丙烯(PP)/碳酸钙(CaCO_(3))复合材料,分析了口模拉伸对材料微观结构、晶体结构、热性能和密度的影响,揭示了口模拉伸过程中材料结构演变及其机理。结果表明,随着拉伸过程的进行,材料内的原始球晶向微纤状晶体转变,同时发生晶粒细化现象,结晶度增大表明存在拉伸诱导结晶现象。微孔尺寸的显著增大及材料密度的显著降低主要发生在材料离开收敛流道壁面后的自由拉伸过程中。A type of high-strength,high-modulus,and lightweight polypropylene(PP)/CaCO_(3) composites was prepared using a die drawing method,and the effect of die drawing on the microstructure,crystalline structure,thermal properties,and density of the composites were analyzed.Their structural evolution and corresponding mechanism during the die drawing process were studied.XRD and DSC characterization results indicated that there was a transformation from the original spherulites to fibrous crystals for the composites,and meanwhile a grain refinement took place in the die drawing process.There was a phenomenon of stress-induced crystallization occurring due to an increase in crystallinity.Moreover,a significant increase in the size of micro-voids and a remarkable decrease in density mainly occurred in the free-stretching process after the composites were separated from the converging flow channel wall.

关 键 词：口模拉伸 聚丙烯 复合材料 取向 拉伸诱导结晶 微孔 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]