Department of Food Science and Technology, Shanghai Jiao Tong University, 800 Dongchuang Road, Shanghai 200240, China; SJTU-OSU Innovation Center for Environmental Sustainability and Food Control, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Department of Food Science and Technology, Shanghai Jiao Tong University, 800 Dongchuang Road, Shanghai 200240, China; SJTU-OSU Innovation Center for Environmental Sustainability and Food Control, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Carbohydr Polym. 2019 May 15;212:197-205. doi: 10.1016/j.carbpol.2019.02.048. Epub 2019 Feb 16.
Chitosan (CH) films were prepared with different number-average molecular weight (MW, ca. 6.55, 12.93 and 47.70 kDa) and concentration (0.5, 0.75, and 1.0%) using electrostatic spraying (ES) technique. The effects of MW on film-forming solution properties, ES-atomization performances, and film characteristics were investigated. With increase of MW, conductivity, viscosity, surface tension, and contact angle of CH film-forming solution was raised due to the increases of proportions of amine-groups and degrees of CH chain entanglements. Spray cone angle was generally higher at 12.93 kDa, while the average median diameters of film-forming solution droplets were in the range of 6.3-12.0 μm, indicating well atomization effect. Water barrier property and tensile strength of CH films were improved along with increased MW, which was in accordance with the more completed, rougher and more crystalline microstructures implying by SEM, AFM and XRD. However, film antibacterial capacities against E.coli and L. innocua were descended with increased MW. Considering the overall properties, CH film prepared by 47.70 kDa at 0.5% possessed the best performances.
采用静电纺丝技术，制备了不同数均分子量（MW，约为 6.55、12.93 和 47.70 kDa）和浓度（0.5%、0.75%和 1.0%）的壳聚糖（CH）薄膜。考察了 MW 对成膜溶液性能、ES 雾化性能和薄膜特性的影响。随着 MW 的增加，由于胺基比例和 CH 链缠结程度的增加，CH 成膜溶液的电导率、粘度、表面张力和接触角增大。在 12.93 kDa 时，喷雾锥角通常较高，而成膜溶液液滴的平均中值直径在 6.3-12.0 μm 范围内，表明雾化效果良好。CH 薄膜的水阻隔性能和拉伸强度随 MW 的增加而提高，这与 SEM、AFM 和 XRD 所表明的更完整、更粗糙和更结晶的微观结构一致。然而，MW 增加会降低 CH 薄膜对大肠杆菌和无害李斯特菌的抗菌能力。综合考虑各项性能，47.70 kDa 的 CH 薄膜在 0.5%浓度下具有最佳性能。
