Investigation of the hydrogen-bonding structure and miscibility for PU/EP IPN nanocomposites by PALS
Investigation of the hydrogen-bonding structure and miscibility for PU/EP IPN nanocomposites by PALS
复制标题
DOI：
10.1021/ma0621066
复制
发表时间：
2006-12
期刊：
影响因子：
5.5
通讯作者：
Yuchan Zhu;Bo Wang;W. Gong;Ling-Ge Kong;Q. Jia
中科院分区：
文献类型：
--
作者：
Yuchan Zhu;Bo Wang;W. Gong;Ling-Ge Kong;Q. Jia
利用正电子湮没寿命谱(PALS)、傅里叶变换红外光谱(FTIR)和动态力学分析(DMA)研究了氢键对PU/EP互穿聚合物网络(IPN)纳米复合材料自由体积和相容性能的影响。红外光谱分析表明，PU中两种氢键作用的强度与层状蒙脱土在基质中的分散状态密切相关，这两种氢键作用包括N-−-H基团之间的氢键作用和PU与硅酸盐层间的氢键作用。研究发现，氢键作用越强，平均堆积效率越高，自由体积孔尺寸越小，相容性越好。另一方面，从自由体积和损耗因子的分布分析来看，蒙脱土的剥离结构和插层结构之间的巨大差异是非常有趣的。
Effects of hydrogen bonding on the free volume and miscibility were first investigated for polyurethane/epoxy resin (PU/EP) interpenetrating polymer network (IPN) nanocomposites by positron annihilation lifetime spectroscopy (PALS), Fourier transform infrared spectroscopy (FTIR), and dynamic mechanical analysis (DMA). Infrared spectroscopy suggested that the strengths of two kinds of hydrogen-bonding interactions including both between carbonyl group and N−H group and the other between urethane group in PU and silicate layers depended strongly on the dispersed state of the layered montmorillonite (MMT) in the matrix. We found that the stronger the hydrogen-bonding interaction, the higher the average chain packing efficiency and the smaller the free volume hole size, the better the miscibility. On the other hand, from the analyses of distributions of the free volume and the loss factor, it is very interesting that the large differences between the exfoliated structure and the intercalated structure of MMT ...