Electrospinning of polycarbonates: A study of the morphological features of electrospun fibers as function of the solvent used and processing voltage

Unlike conventional spin methods, electrospinning is capable of yielding fibers with submicron range diameters and high specific surface areas. In this study a Bisphenol-A polycarbonate was electrospun using two solvents: Chloroform and a 1:1 mixture of Tetrahydrofuran (THF) and Dimethylformamide (DMF). The morphological features of the electrospun polycarbonate fibers have been studied as a function of the solvent used and also as a function of the processing voltage. The studies were conducted using the SEM, TEM and Scion image analysis program. The results indicate that the morphological features of the fiber such as fiber diameter, diameter-distribution, internal structure and the Bead density variation with voltage are dependent on the solvent used. Electrospun polycarbonate fibers also exhibit a “Raisin like” puckered structure. However, such a feature is independent of the solvent used, and could enhance the functional efficiency of an electrospun material when used in an area-based application. In addition, studies on crazing of bulk polycarbonate and the surface features of electrospun polycarbonate fibers have been conducted. Results indicate that crazing of bulk polycarbonate results in surface damages and features that are also seen on the surface of electrospun polycarbonates. There has been no effort until now to relate the effect of crazing on a plastic, like bulk polycarbonate, and the surface features of electrospun polycarbonate micro-fibers and to study the possibility of using an engineering plastic like polycarbonate, which offers good mechanical properties at a reduced weight, as an electrospin material.