两步法制备剥离型聚丙烯/蒙脱土纳米复合材料(Ⅰ)制备、表征及力学性能

采用两步法制备了剥离型聚丙烯/蒙脱土纳米复合材料 (PMN).两步法即：在使用高活性极性单体丙烯酰胺 (AM)原位聚合插层有机蒙脱土 (O-MMT)的同时，使部分丙烯酰胺接枝到聚丙烯 (PP)大分子链上，从而得到黏土片层已剥离且与PP又具有良好相容性的材料，以此为母料再与PP熔融共混即制备出剥离型聚丙烯/蒙脱土纳米复合材料.XRD表明，复合材料中蒙脱土片层已剥离；扫描电镜观测不到明显的有机-无机相畴，表明蒙脱土片层分散均匀，分散个体尺寸基本达到纳米级；力学测试表明，该复合材料的拉伸强度达42.4MPa，较基体增加了26%，缺口冲击强度达10.5kJ•m^-2，较基体增加了155%.研究结果表明复合材料达到了预期强韧化效果.

PREPARATION OF EXFOLIATED POLYPROPYLENE/MONTMORILLONITE NANOCOMPOSITES BY TWO-STEP METHOD(Ⅰ) PREPARATION, CHARACTERATION AND MECHANICAL PROPERTIES

A“two-step” method successfully in preparing polypropylene/montmorillonite nanocomposites (PMN) was introduced.In the first step, most amount of acrylamide (AM) was polymerized in-situ and intercalated into organic-montmorillonite (O-MMT) and at the same time a little amount of AM was grafted on polypropylene macromolecule chains. In the second step, the mother matrix prepared in the first step was blended with polypropylene (PP) to produce the PMN.XRD spectra showed that the montmorillonite in the composites had been exfoliated.SEM indecated absence of clear organic and inorganic phases in PMN. The tensile strength of PMN achieved 42.4MPa, which was increased by 26% against pure PP. The maximum value of toughness strength was 10.5kJ•m^-2, which was increased by 155% against pure PP. The results showed that the mechanical properties of PMN reached a desired level.