添加剂改性玉米醇溶蛋白复合膜的制备与表征

Performance and Characterization of Additive-Modified Zein Composite Films

摘要:

采用流延法制备高含量玉米醇溶蛋白（Zein）的Zein/壳聚糖（CS）复合膜，通过复合添加剂〔m(甘油)：m(聚乙二醇400)=1:1〕对Zein/CS复合膜共混改性，研究复合添加剂添加量（以总溶液质量计，分别为0、0.5%、1.0%、1.5%、2.0%）对薄膜的力学、光学和热学性能等的影响，并通过SEM、FTIR对薄膜形貌和结构变化进行表征。结果表明，复合添加剂通过削弱Zein和CS之间的分子间作用力，达到增塑效果，薄膜综合机械性能有所改善，随着复合添加剂添加量的升高，薄膜断裂伸长率逐渐增强，拉伸强度呈下降再上升的趋势；水蒸气透过率逐渐增加，水接触角逐渐减小，薄膜亲水性随之增强。与不含复合添加剂的薄膜（ZC-0）相比，当复合添加剂添加量为1.5%时，复合膜（ZC-1.5）的抗拉强度降低了27.40%，断裂伸长率增长了39.87%，水蒸气透过率上升了29.10%。通过SEM和DSC观察，添加复合添加剂改性后，改善了Zein和CS之间的相容性，制备的薄膜表面更加平整光滑。综合性能可得，制备高含量Zein的Zein/CS复合膜，复合添加剂浓度为1.5%时，薄膜性能最优。并在含有1.5%复合添加剂的Zein/CS薄膜中添加了一定量的姜黄素，据测定其能够有效提高薄膜的抗氧化性能至55.18%。

Abstract:

The Zein/chitosan (CS) composite film with high content of Zein was prepared by casting method, and the film was blended and modified by composite additives [m(glycerol):m(polyethylene glycol 400)=1:1]. The effects of the additive amount of the composite additives (0, 0.5%, 1.0%, 1.5%, 2.0%, respectively, based on the total solution mass) on the mechanical, optical and thermal properties of the film were studied. The morphology and structure of the film were characterized by SEM and FTIR. The results showed that the composite additives could achieve the plasticizing effect by weakening the intermolecular force between Zein and CS, and the comprehensive mechanical properties of the film are improved. With the increase of the additive amount of the composite additives, the elongation at break of the film gradually increased, and the tensile strength decreased and then increased, the WVP increased gradually, the water contact angle decreased gradually, and the hydrophilicity of the film increased. Compared with the film without composite additives, when the concentration of composite additives reached 1.5%, the tensile strength decreased by 27.40%, the breaking elongation increased by 39.87%. The barrier performance decreased, and the WVP increased by 29.10%. Through the observation of SEM and DSC, the compatibility between Zein and CS was improved after adding composite additives, and the surface of the prepared film was more flat and smooth. with high content of Zein, the Zein/CS film has the best performance when the concentration of the composite additive is 1.5%. Adding curcumin to zein/cs composite membrane could effectively improve the oxidation resistance of the film, and with the increase of curcumin content, the proportion of bound water in the film increased, and the mechanical properties of the composite membrane were better than those without curcumin.