摘要
以兼备良好力学性能与加工性能的宽分子量分布聚丙烯为原料,使用生产效率更高的双螺杆反应挤出法,采取自由基熔融接枝的方式以2种不同反应挤出温度来制备长支链聚丙烯,并研究了接枝长支链对于材料性能的影响。通过凝胶渗透色谱仪器(GPC)、傅里叶红外光谱仪(FTIR)和流变仪表征改性产物的分子量及其分布、单体接枝率以及拉伸流变行为,从而证明长支链的成功制备。力学性能测试结果表明,改性产物的力学性能随着反应温度的增加而下降。随着长支链含量的增加,力学性能可小幅度回升。差示扫描量热分析结果表明,随着长支链含量的增加,结晶温度得到显著提升。加工温度200℃且单体添加量为4%(质量分数,下同)时结晶温度升高11℃。
The polypropylene(PP)with a broad molecular weight distribution was used as a matrix for preparing long-branched chain PP due to its excellent mechanical properties and processability.The twin-screw reactive extrusion was carried out to prepare the long branched-chain PP,enhancing the production efficiency.Additionally,melt radical graft-ing was conducted at two different temperature.The effect of long chain-branched structure on the properties of PP was investigated by using gel permeation chromatography,Fourier-transform infrared spectroscopy,and rheometry to deter-mine the molecular weight and distribution,grafting degree,and tensile rheological behavior of the of the as-prepared PP.The mechanical test results indicated that the mechanical properties of the as-prepared PP decreased with an increase in the reaction temperature;however,its mechanical strength increased slightly with an increase in the content of long branched chains.The thermal analysis demonstrated that there was a significant increase in the crystallization tempera-ture of PP but a decrease in its degree of crystallinity with an increase in the content of long branched chains.The crystal-lization temperature was increased by 11℃ at a processing temperature of 200℃ and a monomer content of 4 wt%com-pared to pure PP.
作者
许巍
吕明福
杜文杰
郭鹏
徐耀辉
XU Wei;LYU Mingfu;DU Wenjie;GUO Peng;XU Yaohui(Sinopec Beijing Research Institute of Chemical Industry,Beijing 100013,China)
出处
《中国塑料》
北大核心
2025年第2期6-11,共6页
China Plastics
关键词
宽分子量分布
聚丙烯
双螺杆
反应挤出
长支链
broad molecular weight distribution
polypropylene
twin-screw
reaction extrusion
long branched chain
