纳米银/壳聚糖复合膜的制备及性能

目的将纳米银(AgNPs)加入到壳聚糖(CS)中制备AgNPs复合膜,探究AgNPs的含量(质量分数为0.5%,1%,2%)对复合膜的结构与性能的影响。方法采用柑橘皮提取液还原合成AgNPs粒子,与CS通过共混流延法制备复合膜,测定复合膜的红外光谱、微观形貌、溶胀率、溶解度、拉伸性能和抑菌效果等。结果采用柑橘皮提取液还原合成的AgNPs在CS基材中具有较好的分散性。当AgNPs的质量分数为1%及以上时,复合膜的结晶度降低,溶胀率和溶解度显著增加,拉伸强度和断裂伸长率均显著降低。复合膜对大肠杆菌和金黄色葡萄球菌的生长抑制效果均随AgNPs含量的增加而显著增强。结论AgNPs在CS基材中分散良好,并大大增强了复合膜的抗菌活性。

Preparation and Performance of Nano-silver/chitosan Composite Films

The work aims to prepare the AgNPs composite films by adding the nano-silver (AgNPs) to chitosan (CS), so as to investigate the effect of AgNPs content (mass fraction: 0.5%, 1% and 2%) on the structure and performance of the composite films. AgNPs were firstly synthesized via reduction by citrus peel extract, and then were incorporated into CS to prepare the composite films through blending casting. The FTIR spectra, micro-morphologies, swelling ratio and solubility, tensile properties and antibacterial effects of the composite films were measured. AgNPs synthesized via reduction with citrus peel extract showed good dispersion in chitosan matrix. When the mass fraction of AgNPs was 1% or above, the degree of crystallinity of the composite films was deceased. Therefore, the swelling ratio and solubility of the composite films were significantly increased, and the tensile strength and elongation at break were remarkably decreased. However, the inhibition effect of the composite films toward the growth of E. coli and S.aureus was significantly enhanced with the increasing content of AgNPs. AgNPs are well dispersed in chitosan matrix, and significantly improve the antibacterial activities of the composite films.