增容剂对动态硫化氯化丁基橡胶/尼龙12热塑性弹性体性能的影响

摘要

分别以聚丙烯接枝马来酸酐( PP -g - MAH)、苯乙烯-乙烯-丁二烯-苯乙烯共聚物接枝马来酸酐(SEBS-g- MAH)以及新型改性剂苯乙烯-共轭二烯烃嵌段共聚物选择加氢物(SEPS)作为增容剂,考察了不同增容剂对动态硫化氯化丁基橡胶/尼龙12热塑性弹性体(PA 12/CIIR TPV)物理机械性能的影响,并研究了PP -g - MAH增容TPV的相态结构以及流变性能、结晶性能、动态力学性能、气密性.结果表明,与SEBS-g- MAH、SEPS相比,PP -g - MAH对TPV的增容效果更显著；随着PP -g - MAH用量的增加,TPV中橡胶相平均粒径减小,分散更均匀,两相界面更模糊；在相同剪切速率下,PP -g - MAH增容TPV的黏度比未加增容剂时有明显下降,随着PP -g - MAH用量的增加,TPV表现黏度对剪切速率的变化越敏感,挤出物外观由光滑转变为竹节状,动态力学性能提高,但结晶性能和气密性下降,综合考虑,PP -g - MAH的最佳用量为5份.%Effects of different kinds of compatibilizers, such as polypropylene grafted maleic anhydride ( PP-gMAH) , styrene-ethylene-butadiene-styrene copolymer grafted maleic anhydride (SEBS-g-MAH) and hydrogenated styreneisoprene-styrene block copolymer( SEPS) on properties of the chlorinated butyl rubber/polyamide 12 thermoplastic vulcanizates( CⅡR/PA 12 TPV) were investigated. The morphology, rheological properties, crystallization property, dynamic mechanical properties and air permeability of CIIR/PA 12 TPV with PP-g-MAH were studied. The results showed that, compared with SEBS-g-MAH and SEPS, PP-g-MAH had more effective compatibilization to CIIR/PA 12 TPV. With increasing PP-g-MAH amount, the average diameter of rubber phase particles decreased, the particles dispersed uniformly in resin phase, and the phase interface became ambiguous. At the same shearing rate, the apparent viscosity of TPV with PP-gMAH was smaller than that of TPV without compatibilizer. With increasing PP-g-MAH amount, the apparent viscosity was sensitive to shearing rate, the extrudate appearance changed from smooth to bamboo-ridge, the dynamic mechanical properties was improved, and the crystallization property and air permeability decreased.