聚氨酯弹性体/蒙脱土纳米复合材料的合成与性能

采用聚氨酯本体预聚法 ,利用原位插层聚合合成了聚氨酯 蒙脱土纳米复合材料 .通过X 射线衍射(XRD)和Molau实验研究了蒙脱土在复合材料中的分散情况 .红外分析 (IR)表明随着蒙脱土含量的增加 ,复合材料羰基氢键减少 .动态力学分析 (DMA)以及差热分析 (DSC)结果说明随着蒙脱土含量的增加 ,材料的玻璃化温度降低 .聚氨酯纳米复合材料的拉伸强度和断裂伸长率同时提高 ,表现出较好的力学性能 .

SYNTHESIS AND CHARACTERIZATION OF ELASTOMERIC POLYURETHANE/MONTMORILLONITE NANOCOMPOSITES

A novel elastomeric polyurethane/montmorillonite nanocomposite based on poly(propylene glycol),4,4′-diphenylmethane diisocynate and 1,4-butanediol was synthesized by intercalative polymerization technology.Octadecylamine was used as swelling agents to treat Na- montmorillonite and form organomontmorillonite through ion exchange.Nanoscale dispersing of clay in the nanocomposite was analyzed by X-ray diffraction and Molau experiment.At the same time,X-ray diffraction result showed that the intercalated nanocomposites were formed.Hydrogen bonding in the hard segments of the synthesized polyurethane/montmorillonite nanocomposite was found to decrease with the increasing amount of montmorillonite,but reached a minimum at 5 wt% montmorillonite concentration,as was evidenced by FTIR studies.DMA and DSC results showed that the glass transition temperature was reduced with increasing of montmorillonite concentration.Introducing 3% organomontmorillonite in the composites resulted in a 45% increase in the tensile strength and a 35% increase in the elongation as compared to thoee of pure PU.