聚氨酯/壳聚糖互穿聚合物网络涂层再生纤维素膜的生物降解性

研究了聚氨酯 /壳聚糖互穿聚合物网络涂层的再生纤维素防水膜在土壤中的生物降解性。粘度法和降解失重实验结果表明纤维素的粘均分子量Mη 和降解膜的重量随降解时间的延长而降低 ,再生纤维素膜(RC)和涂层膜 (RCCH)在土壤中 30℃下的降解半衰期分别为 1 9天和 32天。扫描电镜 (SEM)、示差扫描量热法 (DSC)和红外光谱 (IR)实验结果证明在土壤中微生物直接进攻防水涂层表面 ,然后进入纤维素并迅速代谢。涂层中的聚氨酯和壳聚糖被微生物缓慢分解成芳香醚和单糖衍生物 ,因此是可完全生物降解膜

Biodegradability of Regenerated Cellulose Films Coated with Polyurethane/Chitosan Interpenetrating Polymer Networks

The biodegradability of regenerated cellulose films coated with polyurethane/chitosan interpenetrating polymer networks in soil was studied by viscometer, weight loss, scanning electron microscopy (SEM),differential scanning calorimetry (DSC) and infrared (IR).The viscosity average molecular weight (M η) of the cellulose and the weight of the degraded films decreased sharply with the progress of degradation.The degradation half-lifes,t 1/2 ,of the films in soil at 30℃ were 19 days for RC film and 32 days for RCCH films.Experimental results suggest that the microorganisms directly attacked the water-resistant coating layer,penetrated into the cellulose,and then metabolized quickly converting the coating layer into glucopyranose derivatives and aromatic ether.This indicates that the regenerated cellulose films coated with polyurethane/chitosan are completely biodegradable.