小麦麸质/聚氨酯共混材料的结构与吸水性

Structure and Water Uptake of Wheat Gluten Water-Borne Cationic Polyurethane Blends

合成了水性阳离子聚氨酯(WCPU),与小麦麸质(WG)溶液共混、冷冻干燥成粉,经热压后成共混片材。对WG/WCPU模压片材进行红外测试,对小麦蛋白酰胺Ⅰ区红外吸收峰经最小二乘法拟合分峰,结果表明小麦麸质蛋白的β-折叠结构的氢键化程度随WCPU质量分数的增加而呈现先减小后增大的趋势,WCPU可有效破坏小麦蛋白的氢键作用而增塑WG材料。对WG/WCPU热压片进行吸水性分析,结果显示WG/wCPU共混片的吸水溶胀初期为菲克溶胀过程,水分子扩散起决定作用。扫描电子显微镜(SEM)研究结果表明WG和WCPU共混效果良好。

Water-borne cationic polyurethane （WCPU） was prepared and blended with wheat gluten （WG） in solution. The blend powder of WG/WCPU was obtained by freeze-dryer and thermally compression-molded to form a blend sheet. FT-IR was used to analyze the secondary structure of the WG/ WCPU blends. The absorption in the amide I of wheat protein was separated by least squares curve fitting. The results show that the hydrogen-bonding of fl sheets in WG decreases firstly, and then increases with increasing the content of WCPU in blends. The hydrogen-bonding was weakened by WCPU, and the WG/ WCPU blend sheets were plasticized. The water uptake of the blend sheets is a Fick＇s process, and the water diffusion in the sheets is predominant. Scanning electron microscope （SEM） images of the WG/ WCPU blends reflect the fact that the blending of WG and WCPU is effective and homogenous.