山梨酸-LDPE抗菌薄膜的制备与性能

目的研究山梨酸对低密度聚乙烯(LDPE)薄膜性能的影响。方法将山梨酸粉末添加到低密度聚乙烯树脂中,通过共混、挤出、吹塑等工艺制备出山梨酸-LDPE抗菌薄膜,并研究山梨酸含量对LDPE薄膜的抗张强度、光学性能、水蒸气透过率、微观结构及抗菌性的影响。结果随着山梨酸含量的增加,薄膜的抗张强度先增加再减小,透光率逐渐下降,雾度逐渐上升,薄膜的水蒸气透过系数先下降后上升,山梨酸质量分数在1.5%以上时对大肠杆菌具有抑制作用,在2%以上时对单增李斯特菌和金黄色葡萄球菌具有抑制作用。结论山梨酸-LDPE薄膜具有优良的包装性能和抑菌效果,是一种良好的食品包装材料。

Preparation and Properties of Sorbic Acid- LDPE Antibacterial Films

This work was aimed to study the effect of sorbic acid on the properties of low density polyethylene (LDPE) film. Sorbic acid powder was added to low density polyethylene resin. By blending, extrusion, blow molding and other processes, antibacterial sorbic acid-LDPE film was prepared. And the effects of sorbic acid content on the tensile strength, optical properties, water vapor transmittance, microstructure and antimicrobial properties of LDPE film were studied. With the increase of sorbic acid content, the tensile strength of the film first increased and then decreased, the transparency decreased gradually and the haze gradually increased, the trend of permeability coefficient first decreased and then increased. More than 1.5% of sorbic acid content in the film had inhibitory effect on E. coli, while more than 2% of sorbic acid content had inhibitory effect on L. monocytogenes and S. aureus. In conclusion, the sorbic acid-LDPE Films have good packaging property and inhibitory effect, and can be used as a kind of good material for food packaging.