超细电纺纳米纤维的直接制备(英文)

Direct Fabrication of Ultrafine Electrospinning Nanofiber

采用装配有疏水铜网的新型喷头研究了超细纳米纤维的制备.静电纺丝实现之前,首先对铜网进行了疏水处理,并将其安装于喷头前端.静电纺丝过程中,聚合物溶液由精密注射泵输送至喷头处.安装于喷头的铜网可将管道内的聚合物溶液分成多股细流从铜网网孔中流出.从铜网网孔流出的溶液细流受电场力作用被拉伸成多股独立射流,并从喷头携带走聚集的正电荷.受铜网表面疏水性和射流间电荷排斥力的影响,从铜网喷射出的多股射流都将保持其独立的轨迹而不会产生聚集.疏水铜网有利于减小纺丝射流的初始直径,并获得均匀的超细纳米纤维.利用新型的电纺丝喷头成功制备了直径20～80 nm的聚氧化乙烯(PEO)和聚乙烯醇(PVA)超细纳米纤维.实验结果表明,超细纳米纤维的直径随着电纺丝溶液浓度的增加而变大.

A novel spinneret assembled with Cu grid was presented in this paper to fabricate ultrafine nanofiber directly. Before electrospinning, hydrophobic treatment was performed on the Cu grid, which was then fixed at the front end of spinneret. During electrospinning, the polymer solution was transferred to the spinneret by the precise syringe pump. Through the holes in the Cu grid, polymer solution flow was divided into several smaller ones. The fine liquid flow from each hole of Cu grid was stretched into individual jets by the electric field force, and the liquid jets carried away the positive charges accumulated on the spinneret. Due to the hydrophobic treatment and the charge repulsive force between charged jets, liquid jets emanated from Cu grid kept their own tracks without aggregation. The initial diameter of liquid jet was greatly decreased by the Cu grid after hydrophobic treatment, and the smaller jet led to finer uniform nanofiber. Polyethylene oxide （PEO） and polyvinyl alcohol （PVA） uhrafine nanofiber with the diameter of 20-80 nm were fabricated by this novel spinneret, and the diameter of uhrafine nanofiber increases with the increase of polymer solution concentration.