【摘要】 为研究壳聚糖(CS)、茶多酚(TP)和聚乳酸(PLA)3种物质所得复合膜的性能效果,采用流延成膜法,制备不同CS与TP质量比的PLA–CS–TP复合膜。通过测试纯PLA膜及各复合膜的密度、力学性能、热封性能、水蒸气透过率和溶解度等指标,对比分析了复合膜的综合性能,研究其实用价值。结果表明,相比纯PLA膜,CS与TP的加入使复合膜的密度和拉伸性能明显降低,但显著提高了复合膜的热封强度、水蒸气透过率和溶解度。当CS与TP质量比为3/7时,热封强度最高,比纯PLA膜提高了245.72%;当CS与TP质量比为5/5时,水蒸气透过率最高,比纯PLA膜提高了28.59%;当CS与TP质量比为1/9时,溶解度最高,比纯PLA膜提高了758.04%。复合膜具有较好的热封性、透湿率和溶解度,在食品包装领域有较好的应用潜力,可使无花果在5℃下的保存期由2 d延长至13 d以上。更多还原

【Abstract】 For the study of the effects of three kinds of poly(lactic acid)(PLA),chitosan(CS) and tea polyphenols(TP) on performances of PLA–CS–TP composite membrane,the preparation of the composite membranes with different mass ratio of CS/TP were made by stretch film method. By testing density,mechanical properties,heat sealing strength,water vapor transmittance and solubility of the pure PLA membrane and composite membranes,the comprehensive performances of the composite membrane were analyzed contrastively for researching the actual use value. The results show that compared with the pure PLA membrane,adding CS and TP significantly decreases the density and tensile properties of the composite membrane,but can obviously improve the heat sealing strength,water vapor transmittance and solubility,when the mass ratio of CS/TP is 3/7,the heat sealing strength reaches highest and improves by 245.72%,when the mass ratio of CS/TP is 5/5,the water vapor transmittance is maximum and improves by 28.59%,when the mass ratio of CS/TP is 1/9,the water vapor transmittance is maximum and improves by 758.04%. The composite membrane has good heat sealing property,moisture permeability and solubility,and has good application potential in the field of food packaging,which can extend the shelf life of the figs at 5℃ from 2 d to more than 13 d.更多还原