静电纺丝制备多孔醋酸纤维素超细纤维

Fabrication of Porous Cellulose Acetate Ultrafine Fibers Through Electrospinning

采用静电纺丝法制备了大量尺寸为60 nm～750 nm椭圆形多孔醋酸纤维素(CA)纤维。利用扫描电镜(SEM)表征了纤维及孔的形态和大小,液氮吸附法(BET)测定了纤维的比表面积。探讨了溶剂种类、溶剂配比和溶液浓度对多孔CA纤维的影响。通过调节纺丝溶液性质和纺丝参数,CA纤维表面多孔大小和分布密度是可调控的。成孔机理是由于溶剂快速挥发引起纤维表面温度急剧降低而引起的热致相分离和水滴辅助成孔,前者成的孔径较小,后者成的孔径较大。研究表明,多孔CA超细纤维的比表面积约为无孔或少孔对照纤维的10倍。

Porous cellulose acetate（CA） ultrafine fibers with pores of 60 nm～750 nm in diameter were prepared by electrospinning.The fiber morphology and pore structure were characterized by scanning electron microscopy.The specific surface areas were measured by the Brunauer-Emmett-Teller（BET） method.It is found that the pore diameter and distribution can be regulated by adjusting the nature of the spinning solutions and electrospinning parameters.The porous with diameters less than 80 nm on the CA ultrafine fibers were formed by the thermally induced phase separation,which was caused by the rapid solvent evaporation.The pores with size of 200 nm～400 nm were produced by the water drop templating method.The pore structure of CA ultrafine fibers substantially increased the specific surface areas,as a result,the specific surface areas of porous CA fibers were 10 times more than that of pore free CA fibers.