偶联剂改性填料对SEBS/PP复合材料性能的影响

摘要

采用异丙基三（二辛基焦磷酸酰氧基）钛酸酯（NDZ-201）偶联剂和3-氨丙基三乙氧基硅烷（KH-550）偶联剂对碳酸钙和滑石粉无机纳米填料进行表面改性处理，然后与聚苯乙烯-聚乙烯-聚丁烯-聚苯乙烯（SEBS）和聚丙烯（PP）在双螺杆挤出机上进行共混制备SEBS/PP/填料复合材料，研究偶联剂及其改性填料对SEBS/PP复合材料的力学性能、加工行为、微观结构和热性能的影响.实验结果表明，NDZ-201与KH-550复配改性的填料在复合材料中分散均匀，形成的相界面模糊，有效提高了复合材料的拉伸强度、断裂伸长率、300%定伸强度和邵氏A硬度.少量的改性滑石粉会在复合体系中比较均匀地分散，起到增强作用；当其用量较多时，会不均匀地分散在SEBS/PP基体中，不同程度地发生附聚或粉聚的现象，导致材料某些性能下降.随着改性滑石粉用量的增加，复合材料的热稳定性提高，当滑石粉的用量为15 g时，复合材料的分解温度提高了10℃.%The inorganic fillers of calcium carbonate and talc powders were treated by coupling agents of isopropyltri(dioctylpyrophosphate)titanate(NDZ-201)and 3-aminopropyltriethoxysilane(KH-550). And then they were blended with poly(styrene-b-ethylene-co-butadiene-b-styrene)(SEBS),polypropylene(PP)and white oil by the twin screw extruder to prepare the SEBS/PP composites. Subsequently,the influence of coupling agents and modified fillers on the mechanical properties,processing behavior,microstructure and thermal properties of SEBS/PP composites were explored. The experiment results illustrate that the fillers treated with the combination of NDZ-201 and KH-550 can disperse uniformly and form the good phase interface in the composites,which improves the tensile strength,elongation at break,300% modulus and hardness(Shore A). The modified talcum powders disperse uniformly in the composites when the filler content is low improves their performance;when the content of talcum powders is high,the talcum powders disperse heterogeneously in composites and some agglomeration appears in the composite matrix,resulting in decreasing some properties of composites. However,the thermal stability of composite materials increases gradually with the addition of talc powders,and the decomposition temperature of composite materials increases 10 ℃ when the content of talcum powders is 15 g .