Na Si and Lan Xu
Accepted Abstracts: J Nanomed Nanotechnol
The surface morphology of electrospinning fibers is crucial when considering end-use applications. Electrospinning fibers with high surface area, inter-fiber pores and unique properties have drawn interests in research for potential applications in diverse fields. In this paper, we reported an effective and simple approach to prepare highly porous PLA fibers directly via electrospinning. PLA was dissolved in the solvent mixtures of N, N-dimethylformamide (DMF) and CHCL3 (CF). As the solvent evaporated in combination with high fiber stretching under the electrical force, the concentrated polymer-rich phase solidified into the matrix, whereas the solvent-rich phase eventually transformed into the pores as solvent dried out. The porous structures of the fibrous mats were characterized by field emission scanning electron microscopy to confirm that they could be accurately controlled by tuning vapor pressure of CHCL3 (CF) and N,N-dimethylformamide (DMF) solvent mixtures. The effects of the solvent compositions on the characteristics of as-spun fibers such as pore size and pore distribution were intensively investigated. The viscosity of mixed solvents of CF and DMF with various weight ratios of 10/0, 8/2, 5/5, 2/8 and 0/10 were decreased. The surface morphology of fibers electrospun from DMF alone displayed featureless. With CF increased in the solvent mixture, the pore diameter and pore size distribution both increased. The CF/DMF mixing ratio in PLA solutions was proved to be a key parameter to affect porous structure which was induced by phase separation resulting from rapid evaporation of solvent in electrospinning.
Na Si is a postgraduate student in College of Textile and Clothing Engineering, Soochow University. Research include in the field of electrospinning, and nanofibers engineering