PP/PS-海泡石插层纳米复合材料的流变性能与形态结构

Rheological property and morphological structure of PP/PS-sepiolite intercalated nanocomposites

采用苯乙烯乳液聚合法对有机海泡石原位插层,将插层产物聚苯乙烯(PS)-海泡石与聚丙烯(PP)熔融共混制备PP/PS-海泡石插层纳米复合材料。流变测试结果表明:PP/PS-海泡石插层纳米复合材料为典型的假塑性流体,其偏离牛顿流体的程度随PS-海泡石含量增加而增大,表观黏度和零切黏度随着PS-海泡石含量的增加而减小,PS-海泡石有改善PP流动性能的作用。添加PS-海泡石后,复合材料的黏流活化能明显小于纯PP,有利于复合材料在较宽温度范围内加工。扫描电子显微镜观察表明,PS-海泡石以二维纳米级的形式均匀分散在PP基体中,且相容性良好。

The in-situintercalation of organic sepiolite was carried out in the process of styrene emulsion polymerization; the resultant polystyrene（PS）-sepiolite was blended in melt state with polypropylene （PP） so as to prepare PP/PS-sepiolite intercalated nanocomposites. The rheological test results show that the nanocomposites are typical pseudoplastic fluid. The degree of deviation from Newton fluid increases while the apparent viscosity and zero shear viscosity of the nanocomposites decrease as the PS-sepiolite content augments, indicating the role of PS-sepiolite played in improving fluidity of PP. Adding PS-sepiolite can make the nanocomposites have much lower viscous flow activation energy than pure PP, which is in favor of processing the nanocomposites in a wide range of temperatures. The observation under a scanning electron microscope（SEM） reveals that the PS-sepiolite layers were exfoliated and uniformly distributed in the shape of bidimensional nano-particles in the PP matrix, and the compatibility between the two phases proves to be pretty good.