NBR对POM结晶的抑制作用  

Inhibition Effects of NBR on POM Crystallization

作　　者：逯祥洲 王树杰 刘俊卿[2] 魏继军 吕康辉 薛美玲[1] Lu Xiangzhou;Wang Shujie;Liu Junqing;Wei Jijun;Lyu Kanghui;Xue Meiling(College of the Polymer Science and Engineering,Qingdao University of Science and Technology,Qingdao 266042,China;Plastics Research and Development Center of Shandong Province,Jinan 250002,China)

机构地区：[1]青岛科技大学高分子科学与工程学院,山东青岛266042 [2]山东省塑料研究开发中心,济南250002

出　　处：《工程塑料应用》2018年第9期13-18,共6页Engineering Plastics Application

基　　金：国家自然科学基金项目(51673104;51173089)

摘　　要：针对聚甲醛(POM)因其具有结晶速度快、结晶度高、晶体粒径大等特点,而在成型加工大制件时易造成翘曲、凹陷等问题,以丁腈橡胶(NBR)作为抑制剂,抑制和干扰POM链的有序排列过程,降低结晶速率以满足快速成型的要求。结果表明,NBR明显抑制POM结晶的成核和生长,结晶温度移向低温,结晶焓显著降低,半峰全宽增加,且球晶生长速率明显下降。NBR的抑制作用随其用量增加和分散性提高而增强。当NBR质量分数为10%时,POM结晶被显著干扰,显示出分步结晶的现象。偏光显微镜结果表明NBR被囊裹在POM微纤之间或被排除在微纤之外,对球晶负光性和晶体结构无影响。According to the problems that the warpage and depression easily occur when polyoxymethylene(POM)is molded to form large size parts due to the POM characteristic including rapid crystallization and high crystallinity as well as large grains,acrylonitrile-butadiene rubber(NBR)was used as an inhibitor to restrain and interfere with the ordered arrangement of POM molecular chains,which forced the crystallization rate to decrease to satisfy the rapid prototyping.The results show that both the nucleation and spherulite growth of POM crystallization are significantly inhibited by NBR,the crystallization temperatures shift to lower temperatures,and crystallization enthalpy decreases significantly,whereas the full width of the half peak increases,and the growth rate of spherulites decreases obviously.The inhibitory effect of NBR increases with the increase of its content and dispersion.The crystallization of POM is significantly interfered when the mass fraction of NBR reaches 10%,which shows the phenomenon of typical fractionated crystallization.The results of polarized optical microscope shows that NBR is encapsulated between the microfibers of POM spherulite or excluded from the microfibrils,and has no effect on the spherulite opticallynegative and crystal structure.

关 键 词：聚甲醛 丁腈橡胶 结晶行为 球晶生长速率 

分 类 号：TQ322.3[化学工程—合成树脂塑料工业]