高通量醋酸纤维素复合膜的制备及性能测试

Preparation and Characterization of High Flux Cellulose Acetate Composite Membrane

以醋酸纤维素(CA)为膜阻隔层,聚羟基丁酸/戊酸酯共聚物(PHBV)作为膜支撑层,利用静电纺丝法制备出复合膜。研究了醋酸纤维素质量分数、溶剂配比、电压,以及CA与PHBV复合比(体积比)对纤维形态及复合膜性能的影响,并通过扫描电镜表征了CA纤维膜的表面形貌。研究结果表明,当CA的质量分数为12%,溶剂丙酮与N,N-二甲基乙酰胺(DMAc)体积比为1/1,纺丝电压为14 k V时,CA纤维膜形态均匀,并呈现独特的双纤维直径交错结构。这种结构的膜材料有利于在提高水通量的同时,保持其较好的截留率。同时,当CA/PHBV的复合比为10/10时,复合膜的水通量能达到104数量级,截留率可以达到87%。

Composite membranes were prepared by electrospinning,cellulose acetate( CA) and polyhydroxybutyrate / valerate copolymer( PHBV) were used as barrier layer and based layer of membranes,respectively. The influence of factors of electrospun processes on fiber morphology and property were investigated,such as concentration,solvent,applied voltage and volume ratio of CA / PHBV. The uniform fibers were obtained at the CA concentration of 12%,volume ratio of acetone and N,N-dimethylacetamide( DMAc) of 1 /1,and the spinning voltage of 14 k V. From SEM,the unique structure of CA fibers morphology is observed which possesses two different diameters. This structure could improve the water flux and keep a high rejection ratio. Meanwhile,when the ratio of CA / PHBV composite membrane is10 /10,the water flux reaches four orders of magnitude with the rejection ratio of 87%.