茯苓-聚乙烯醇抑菌膜的制备及生物可降解动力学评价

Preparation and Biodegradability Evaluation of Poria cocos-Poly(Vinyl Alcohol)Antibacterial Film

目的以可降解材料聚乙烯醇为基材,通过添加茯苓溶液,制备出复合抑菌薄膜,研究不同浓度茯苓对共混膜理化性能和功能性能的影响。方法采用溶剂浇铸法制备茯苓/PVA共混膜。对共混膜的物理力学性能,以及溶解度、透光率、抑菌性、可降解性进行检测。利用红外光谱、扫描电镜对其结构进行分析表征。结果茯苓的添加削弱了PVA分子间作用力,显著提高了断裂伸长率,由202.77%增加到398.82%,降低了拉伸强度,并且茯苓与PVA之间形成氢键,减少了水分对薄膜的溶解,薄膜溶解度由100%降到38.21%。随着茯苓质量分数的增加,薄膜的透光率下降,抑菌性得到增强。土壤降解实验表明茯苓/PVA共混膜具有良好的生物降解性。结论制备的茯苓/PVA共混膜的力学性能和耐水性均得到提高,并且复合膜具有一定的抑菌性和可降解性。文中制备的复合膜为食品包装提供了理想选择。

Using degradable material poly(vinyl alcoho1)as substrate,the paper aims to prepare the composite anti-bacterial film by adding Poria cocos solution and study the effects of different concentrations of Poria cocos on the phy-sicochemical and functional properties of the blend film.Poria cocos/PVA blend film was prepared by solvent casting.The physical mechanics,solubility,light transmittance,antibacterial and degradability of the blend films were investi-gated.Its structure was characterized by Fourier transform infrared spectroscopy,and scanning electron microscope.The addition of Poria cocos weakened the intermolecular force of PVA,significantly increased the elongation at break from 202.77%to 398.82%,reduced the tensile strength,and formed a hydrogen bond between Poria cocos and PVA,reducing the dissolution of water to the film,and the solubility of the film decreased from 100%to 38.21%.With the increase of Poria cocos concentration,the light transmittance of the film decreased and the antibacterial activity was enhanced.Soil degradation test showes that Poria cocos/PVA blend membrane has good biodegradability.The mechanical properties and water resistance of Poria cocos/PVA blend film are improved,and the composite film has certain antibacterial and degra-dability.The preparation of the composite film provides an ideal choice for food packaging.