改性魔芋葡甘聚糖纳米晶对聚乙烯醇薄膜性能的影响

Effect of Modified Konjac Glucomannan Nanocrystals on Properties of Poly(vinyl alcohol)Film

通过硫酸水解魔芋葡甘聚糖(KGM)得到魔芋葡甘聚糖纳米晶(NKGM),再表面接枝3-(三甲氧基硅丙基)十八烷基氯化铵,与壬基酚聚氧乙烯醚硫酸钠反应等过程得到改性KGM纳米晶类流体(NKGMf);然后采用溶液流延法制备了含NKGM和NKGMf的聚乙烯醇(PVA)薄膜;通过傅里叶变换红外光谱仪、透射电子显微镜、扫描电子显微镜、热失重分析仪、拉伸测试仪等对NKGM、NKGMf的结构和PVA薄膜的性能进行表征。结果表明,经改性后,NKGM的片状结构得以保留,在PVA基质中的分散性增加,薄膜的起始分解温度提高了23℃,拉伸强度提高了34.7%,其中,NKGMf的最佳含量为3%(质量分数,下同)。

Konjac glucomman(KGM)nanocrystals were prepared by a hydrolysis reaction of KGM with sulfuric acid and then was modified by surface grafting with 3-(trimethoxysilylpropyl)octadecylammonium chloride and then by ion-exchanging with nonylphenol polyoxyethylene ether sodium sulfate to obtain a KGM nanocrystal fluid.The poly(vinyl alcohol)-based composite films containing different concentrations of KGM nanocrystals and their fluid were prepared by a solution-casting method,and their structures and properties were investigated by Fourier-transform infrared spectroscopy,transmission electron microscopy,scanning electron microscopy,thermogravimetric analysis,and tensile test.The results indicated that the structure of KGM nanocrystals was not destroyed after surface modification,and their fluid was uniformly dispersed in the PVA matrix.The composite films achieved an improvement in initial decomposition temperature by 23°C and in tensile strength 34.7%when 3 wt%of KGM nanocrystal fluid was incoporated.