苯乙烯原位聚合改性氢氧化镁/聚丙烯复合材料的流变特性  

Effect of surface modification of magnesium hydroxide via in situ polymerization of styrene on rheological properties of magnesium hydroxide/polypropylene composites

作　　者：刘生鹏[1,2] 应继儒[1] 周兴平[1] 解孝林[1] 

机构地区：[1]华中科技大学化学与化工学院材料化学与服役失效湖北省重点实验室,武汉430074 [2]武汉工程大学绿色化工过程省部共建重点实验室,武汉430073

出　　处：《复合材料学报》2009年第5期33-38,共6页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金资助项目(50573026)

摘　　要：采用乙烯基硅烷在纳米氢氧化镁(MH)表面引入乙烯基后与苯乙烯进行原位聚合,制备了苯乙烯原位聚合改性氢氧化镁(MMH)。将改性前后的MH分别与聚丙烯(PP)熔融复合制备了不同的MH/PP复合材料,采用扫描电镜和毛细管流变仪研究了复合材料的形态结构和流变特性。结果表明:MH/PP复合材料为剪切变稀的非牛顿流体,其表观黏度、非牛顿指数大于PP。随着填充量的增加,MH/PP复合材料表观黏度增大,非牛顿指数总体上也表现出增大的趋势。低的填充量降低了PP的黏流活化能,随着MH填充量的增加,复合材料的黏流活化能明显增大。然而,MH的苯乙烯原位聚合改性显著改善了复合材料的分散性,改性后MH的"滚珠"效应明显降低了复合材料的表观黏度,非牛顿指数和黏流活化能也比PP熔体的小,且黏流活化能随改性MH填充量的增加而进一步减小。Nano-sized magnesium hydroxide particles（MH） were modified with vinyl silane followed by in situ polymerization of styrene.The MH/polypropylene（PP） composites were prepared by melt compounding of PP with MH and modified MH（MMH）,respectively.The morphological structure and rheological properties were characterized by scanning electron microscopy and capillary rheometer.The results show that the MH/PP composite is a shear-thinning non-Newtonian,and its apparent viscosity and non-Newtonian index（n） are bigger than those of the PP melt.With increasing the MH content,its apparent viscosity and n increase.The low MH content decreases the flow activation energy（ΔE） of the MH/PP composites melts,but ΔE values of the composites increase with MH content.However,the in situ polymerization of styrene on the surface of MH enhances the dispersion of MH in composites.The ＂ball bearing＂ effect of the modified MH particles decreases the apparent viscosity of MMH/PP composites,their n and ΔE values are lower than those of PP,and ΔE values decrease with increasing the MMH content in composites.

关 键 词：聚丙烯 氢氧化镁 树脂基复合材料 表面处理 流变特性 

分 类 号：TB332[一般工业技术—材料科学与工程]