聚N-甲基苯胺/蒙脱土纳米复合材料的合成及其协同电流变效应

用插层聚合法制备了聚N 甲基苯胺 蒙脱土纳米复合材料微粒 ,通过IR、XRD及TEM对其结构进行了表征 .观察发现聚N 甲基苯胺插入蒙脱土层间后 ,蒙脱土片层间距由 0 96nm扩大至 1 34nm .将其分散在甲基硅油中 (2 0wt% )配制成无水电流变液 ,该复合材料表现出显著的协同效应 ,具有较好的电流变行为 .实验表明在电场作用下聚N 甲基苯胺 蒙脱土纳米复合材料的电流变效应比聚苯胺、蒙脱土都有显著提高 ,在 3kV mm(DC ,74 5s- 1 )时 ,剪切强度达 6 0kPa ;同时抗沉降性极好 ,静置 6 0天沉淀率小于 3% .介电性能测试表明聚N 甲基苯胺 蒙脱土纳米颗粒的介电常数和介电损耗较蒙脱土和聚N 甲基苯胺明显提高 ,电导率也达到了最佳范围 .

THE ELECTRORHEOLOGICAL BEHAVIOR OF POLY-N-METHYLANILINE-MONTMORILLONITE NANOCOMPOSITES

Poly N methylaniline/montmorillonite nanocomposite (PNMA MMT) particles with high dielectric constant and suitable conductivity were prepared by an intercalating polymerization method and characterized by IR,XRD and TEM,respectively.The structure analysis showed that the layer spacing of MMT was swelled from 0.96?nm to 1.34?nm and the diameter of PNMA MMT particles was about 30～100?nm.The electrorheological(ER) properties of the suspensions of PNMA MMT particles in silicone oil (20 wt%)were investigated under DC electric fields.It was found that the mechanic performance of PNMA MMT ER fluids displays a notable ER effect under DC current field.The shear stress of PNMA MMT ER fluid was 6.0?kPa ( E =3?kV/mm,74 5?s -1 ),which was 3.6 times as high as that of the ER fluid at zero field.Furthermore,the sedimentation ratio of PNMA MMT ER fluid was about 97% after 60 days.The dielectric constant and the dielectric loss tangent of PNMA MMT nanocomposites were higher than those of the two components, PNMA and MMT.It is apparent that the notable ER effect of PNMA MMT ER fluid was attributed to the prominent dielectric property of the poly N methylaniline montmorillonite nanocomposite particles.