壳聚糖/玉米醇溶蛋白共混膜液体系的流变特性与共混膜的热特性分析

Rheological properties of chitosan / zein blend solutions and thermal characteristic of blend films

摘要:

摘 要：将壳聚糖与玉米醇溶蛋白按不同质量比共混得到系列共混膜液 (C/Z-0、C/Z-1、C/Z-3、C/Z-5)并通过溶液浇铸制得相应共混膜。通过旋转流变仪、SEM及DSC分析不同质量比对共混膜液体系的流变特性、共混膜的微观结构及共混膜热特性的影响。结果表明：不同质量比的共混膜液均具有假塑性，且随着玉米醇溶蛋白质量分数的增加，膜液的稠度系数减小，流动指数增大，流动指数从0.849增加到0.882，共混膜液的活化能均逐渐升高。动态频率扫描流变学分析表明，储能模量和损耗模量均表现出对频率的依赖性，且随着玉米醇溶蛋白质量分数的增加，两者数值均上升，此外交叉点向低频方向移动，表明分子间氢键作用力增强。C/Z-1共混膜中壳聚糖与玉米醇溶蛋白的分子结合紧密，相容性好，这也导致了共混膜热稳定性的提高。

Abstract:

Abstract: The blend solutions (C/Z-0、C/Z-1、C/Z-3、C/Z-5) with different mass ratios of chitosan and zein and then according blend films were prepared by solution casting method. The effects of mss ratios on rheological properties of blend solutions, microstructure and thermal properties of blend films were analyzed by rotational rheometer, SEM and DSC. The results showed that the blend solutions of different ratios all had pseudoplastic properties. With the increase of zein content, the consistency coefficient decreased, and the fluid index increased from 0.849 to 0.882. The activation energy of blend solutions increased gradually. The dynamic frequency scanning rheological analysis showed that the storage modulus and loss modulus were dependent on frequency. With the increase of zein content, both values increased, and the crossing point moved towards the low-frequency, which indicated the intermolecular hydrogen bonds was enhanced. In C/Z-1 blend films, chitosan and zein molecules bound tightly and had good compatibility, which also leaded to the improvement of thermal stability of blend films.