壳聚糖/玉米淀粉交联膜的制备及性能研究

Preparation and performance of chitosan/corn starch crosslinked films

以壳聚糖(CS)和玉米淀粉(St)为原料、柠檬酸(CA)为交联剂,采用流延法制备了CS/St/CA交联膜。研究了CS与St的质量比以及CA的含量对CS/St/CA膜热稳定性、水溶性、阻湿性以及力学性能的影响。结果表明,CA的加入对CS/St膜的性能有明显影响,且当CS/St的质量比为2/1,CA在溶液中的质量分数为2%时,所制备的CS/St/CA交联膜的综合性能最优。此时,薄膜的最大热分解温度为366.3℃,质量保留率为28.29%,含水量为8.16%,水溶性为28.48%,溶胀度为18.72%,薄膜表面的水接触角为101.5°,薄膜的水蒸气透过量为8 g/(m^(2)·24 h),降低了12.25倍,水蒸气透过系数为0.488×10^(-13)g•cm/(cm^(2)·s·Pa),拉伸强度从3.7 MPa提高到了12.5 MPa,断裂伸长率从85.3%提高到了113.2%。

Chitosan(CS)/corn starch(St)/citric acid(CA)crosslinked films were prepared by a tape casting method us⁃ing CS and St as raw materials and CA as a crosslinking agent.The effects of CS and ST contents on the thermal stabili⁃ty,water solubility,moisture resistance,and mechanical properties of the crosslinked films were investigated.The re⁃sults indicated that the addition of CA generated a significant impact on the performance of the crosslinked films,and the as⁃prepared films exhibited the best comprehensive performance when the mass ratio of CS/St was 2∶1 and the mass frac⁃tion of CA in the solution was 2.In this case,the films presented a maximum thermal decomposition temperature of 366.3℃,a mass residue rate of 28.3%,a water content of 8.16 wt%,a water solubility of 28.48%,a swelling de⁃gree of 18.72%,a water contact angle of 101.5°on the film surface.Their water vapor permeability was determined to be 8 g/(m^(2)·24 h),which was reduced by 12.25 times.The films also exhibited a water vapor permeability coefficient of 0.488×10^(-13) g·cm/(cm^(2)·s·Pa).Their tensile strength was increased from 3.7 to 12.5 MPa,and their elongation at break was increased from 85.3%to 113.2%.