Abstract:

In order to obtain a composite film that is not easy to deform with environmental humidity, not easy to gain weight when absorbing water and lose weight when dissolved, we determined chitosan/gelatin/tea polyphenol composite films with 6 different ratios through a formula experiment, prepared them with tape casting method, and tested the water absorption, swelling performance and weight loss of the composite films. The result indicated that the prepared composite films had the lowest water absorption when the mass percentages of chitosan, gelatin, and tea polyphenols were 67.55%, 0%, 32.45%, respectively. At this moment, the swelling rate was close to 0% and the weight loss rate was low. When the proportions of the three components were 63.08%, 7.52%, and 29.40%, the swelling rate of the prepared composite film was 0%, but the water absorption rate was high. When the proportions of the three components were 50.00%, 0%, and 50.00%, the weight loss rate of the composite film prepared was the lowest, but the swelling rate was negative, indicating that the prepared composite film shrank in water. Therefore, the optimal ratio is 67.55% chitosan, 0% gelatin and 32.45% tea polyphenols. The experiment also shows that the introduction of tea polyphenols can significantly overcome the shortcomings of the chitosan/gelatin composite film, which is easy to swell and dissolve when exposed to water.

Key words: chitosan, gelatin, tea polyphenols, water absorption, swelling, weight loss

摘要：

为了获得不易随环境湿度发生形变,不易吸水增重、溶解失重的复合膜,采用配方试验设计确定了6种配比的壳聚糖/明胶/茶多酚复合膜,通过流延法制备了这6种不同配比的壳聚糖/明胶/茶多酚复合膜,对复合膜吸水增重、溶胀性能和失重性能进行测试。结果表明:当壳聚糖、明胶、茶多酚占比分别为67.55%、0%、32.45%时,所制备的复合膜吸水率最小,此时溶胀率接近0%且失重率较小;当3种组分的配比分别为63.08%、7.52%、29.40%时,所制备的复合膜的溶胀率为0%,但此时吸水率较大;当3种组分的配比分别为50.00%、0%、50.00%时,所制备的复合膜失重率最小,但此时溶胀率为负值,所制成的复合膜在水中发生了皱缩。因此最优配比可选用67.55%壳聚糖,0%明胶和32.45%茶多酚。实验同时表明,茶多酚的引入可以大大改善壳聚糖/明胶复合膜遇水易溶胀溶失的缺点。

关键词: 壳聚糖, 明胶, 茶多酚, 吸水性, 溶胀性, 失重性