混炼插层法制备天然橡胶/蒙脱土纳米复合材料

采用有机改性蒙脱土和新型补强性促进剂，通过混炼插层法制备了天然橡胶／蒙脱土纳米复合材料，用X射线衍射和透射电镜表征了纳米复合材料的结构和形态，用表观交联密度测定和红外光谱研究了蒙脱土与橡胶的相互作用，同时用X射线衍射法研究了混炼和硫化过程中天然橡胶分子链对蒙脱土的插层过程．结果表明，蒙脱土在橡胶基体中以纳米级厚度片层分散；补强性促进剂能加强蒙脱土与橡胶间的结合；天然橡胶分子链在混炼过程中便开始对蒙脱土进行插层，并主要在焦烧时间前的硫化诱导期内完成大部分插层过程，硫化开始后蒙脱土的纳米级分散进一步完善，直至硫化完成．添加2％～10％有机蒙脱土的天然橡胶／蒙脱土纳米复合材料的力学性能和动态力学性能优于40％N770炭黑补强的硫化胶．

Natural Rubber/Montmorillonite Nanocomposites Prepared by Mixing Intercalation Method

NR/HMT(Natural Rubber/Organo-Montmorillonite) nanocomposites were prepared with an organic modified montmorillonite and a novel reinforcing accelerator by means of mixing intercalation method.The structure and morphology of the prepared nanocomposites were then characterized by XRD and TEM,and the interaction between montmorillonite and rubber was investigated by the apparent crosslinking density determination and the infrared spectral analysis.Moreover,the intercalation process of rubber chains into the montmorillonite interlayers in the mixing and curing processes was researched by XRD.The results show that montmorillonite can disperse in the rubber matrix in a nanoscale,that the reinforcing accelerator can enhance the interaction between montmorillonite and rubber,that the intercalation of the macromolecular chains of natural rubber into the interlayers of montmorillonite begins in the mixing process and mostly completes in the induced period of vulcanization before the scorch time point,that the dispersion of montmorillonite in a nanoscale is further improved in the curing period till to a complete vulcanization,and that the mechanical and dynamic mechanical properties of NR/HMT nanocomposites with 2%~10% of mass ration of HMT to NR are superior to those of the vulcanizate with 40% of mass ration of N770 carbon black to NR.