不同溶剂对医用聚氨酯/壳聚糖粉体共混膜结构的影响

摘要

Asymmetric blend membranes of chitosan superfine powder and biomedical polyurethane were prepared by immersion-precipitation phase inversion method. The effects of different solvents on the thermodynamics of casting solutions, structure and properties of blended membranes were investigated. The formation of membrane structures was researched in term of the thermodynamics and kinetic diffusion. The results show that the gelation values of three casting solutions from large to small are DO, DMAc and DMF. The pore diameter of upper surface, bottom surface and cross-section of blend membranes from large to small are DMAc, DMF and DO. The change of swelling degree and water vapor transmission rate of three blend membranes is in accordance with that of membrane pore.%以生物医用聚氨酯为基质,添加超细壳聚糖粉体,通过湿法相转变法制备壳聚糖微粉/生物医用聚氨酯共混多孔膜;考察不同溶剂对铸膜液热力学性质及其共混膜结构和性能的影响.从热力学角度和动力学扩散过程探讨不同膜结构的形成.研究结果表明:以DMAc,DMF和DO为溶剂时,制膜体系的凝胶值从大到小分别为DO体系、DMAc体系和DMF体系;3种溶剂体系所制备的膜上、下表面面积以及断面孔径从大至小均为DMAc,DMF和DO,膜的溶胀度和透湿性从大至小为DMAc,DMF和DO.