空气等离子体引发等规聚丙烯/季戊四醇三丙烯酸酯接枝物的结晶行为  

Crystallization Behavior of Polypropylene/Pentaerythritoltriacrylate Grafts Prepared with Air Plasma

作　　者：孟晓梅 马桂秋[1] 马哲 盛京[1] Xiaomei Meng;Guiqiu Ma;Zhe Ma;Jing Sheng(School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学材料科学与工程学院

出　　处：《高分子材料科学与工程》2019年第11期48-53,共6页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51473113);天津市自然科学基金资助项目(12JCYBJC11900)

摘　　要：通过空气等离子体引发等规聚丙烯(iPP)与季戊四醇三丙烯酸酯(PETA)接枝反应,制备了系列iPP-g-PETA接枝物。X射线衍射分析表明,接枝有PETA支链的等规聚丙烯熔体结晶仍形成单斜α晶。采用差示扫描量热仪系统研究了iPP-g-PETA接枝物的结晶行为,发现随着接枝率增加,降温结晶温度逐渐升高,且等温结晶动力学也被加速,其中等温结晶的半结晶时间在0.21%~0.62%接枝率范围内发生陡降。因为结晶动力学是由成核密度和线性生长速度共同决定,本文进一步利用偏光显微镜研究了接枝对球晶生长的作用,134℃的结果表明iPP-g-PETA接枝物的线性生长速度随着接枝率增加反而下降,由此可推断接枝物结晶速度加快的主要原因是成核密度的增加,接枝链的存在有利于异相成核,从而加速了结晶动力学。The air plasma was utilized to induce the grafting reaction of isotactic polypropylene(iPP) and pentaerythritol triacrylate(PETA) to prepare the grafted iPP of iPP-g-PETA. The X-ray diffraction results show that iPP-g-PETA samples still crystallize into the monoclinic α-modification. The crystallization kinetics of iPP-g-PETA was studied in details by differential scanning calorimetry. It is found that as increasing grafting degree, the cooling crystallization temperature is elevated and isothermal crystallization kinetics is accelerated. The most dramatic change in half crystallization time is observed in the grafting ranging from 0.21% to 0.62%. Furthermore, the polarized light microscope experiments were performed to obtain the spherulite linear growth rates in iPP-g-PETA polymers. The decreases of linear growth rate with increasing grafting degree suggests that in the grafted polypropylene, the accelerated kinetics is due to the increased nucleation density.

关 键 词：空气等离子体 聚丙烯 接枝 结晶 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]