EGCG掺入聚乙烯醇/壳聚糖复合薄膜的制备与表征

为了研制一种综合性能更好的环境友好型活性包装材料，以聚乙烯醇和壳聚糖为基材，以表没食子儿茶素没食子酸酯（EGCG）为改性剂，制备了含不同质量分数EGCG的PVA/CS/EGCG复合薄膜。利用紫外-可见分光光度计对复合薄膜紫外光屏蔽性进行表征分析；并对复合薄膜的厚度、色差、光透性、力学性能、抗氧化特性和抗菌活性进行测定。实验结果表明：EGCG的掺入降低了复合薄膜的亮度，使薄膜具有出色的紫外线阻隔性能；提高了复合薄膜的拉伸强度且保持了较高的断裂伸长率；DPPH自由基清除活性随着EGCG添加量的增加而明显提升，说明复合薄膜的抗氧化性显著增强；复合薄膜的抗菌性能得到显著提升，EGCG质量分数为5%的复合薄膜的抑菌率达到92.58%。

Preparation and Characterization of Polyvinyl Alcohol/Chitosan Composite Film Doped with EGCG

In order to develop an environment-friendly active packaging material with better comprehensive properties, PVA/CS/EGCG composite films with different mass fractions of EGCG were prepared by using polyvinyl alcohol and chitosan as substrates and EGCG as the modifier. The UV-visible spectrophotometer was used to characterize the UV shielding of the composite film, and the thickness, color difference, light transmittance, mechanical properties, antioxidant properties and antibacterial activity of the composite film were also measured. The experimental results showed that the incorporation of EGCG reduced the brightness of the composite film and made the film have excellent UV barrier properties, while improved the tensile strength of the composite film and kept high elongation at break. The free radical scavenging activity of DPPH increased significantly with the increase of EGCG content, indicating that the oxidation resistance of the composite film has been significantly enhanced. The antibacterial performance of the composite film was significantly improved, and the antibacterial rate of the composite film with a mass fraction of EGCG of 5% reached 92.58%.