聚丙烯/蒙脱土纳米复合材料的湿热老化性能

Hygrothermal aging performance of polypropylene/montmorillonite nanocomposites

用熔融插层法制备了2种聚丙烯／蒙脱土（PP／OMMT）纳米复合材料，考察了在90℃的水中进行0～80d不同时长的湿热老化后的产物特征。添加少量纳米化蒙脱土的PP表面形貌被破坏时间可延长20d左右，比纯PP拉伸强度保持率提高67．5％，冲击强度保持率提高12．4％。PP、PP／OMMT复合材料湿热老化的损伤主要是环境中的水分子的直接物理作用，其中PP／季铵型OMMT纳米复合材料优良的抗湿热老化能力是其较高的结晶度、剥离性纳米化OMMT片层对水分子和热的物理胆隔效应以及OMMT与PP间较强的相互作用的共同结果。

Two kinds of polypropylene/montmorillonite nanocomposites are prepared with melting intercalation. After hygrothermal aging in distilled water at 90℃ for 0 to 80 days their properties are studied. Adding a small amount of nano-montmorillonite can extend PP＇ s surface breaching time for 20 days, and improve the keeping rate of tensile strength by 67.5% and impact strength by 12.4% ,compared with pure PP. The reason of the hygrothermal aging damage is mainly the direct physical interaction between water molecules and the material. The excellent anti-hygrothermal aging properties of PP/（ quaternary-ammonium-hybrided ） OMMT nanocomposites mainly result from its high crystallinity degree,the physical barrier of OMMT nano-layer to thermal effects and water molecules, and the strong interaction between OMMT and PP.