Melt Electrospinning from Poly(L-lactide) Rods Coated with Poly(ethylene-co-vinyl alcohol)

Rodlike poly(L-lactide) (PLLA) samples coated with poly(ethylene-co-vinyl alcohol) (EVOH) were made. Fibers were produced from these rodlike samples by using a melt electrospinning system equipped with a laser irradiating device, and the effects of EVOH content and the processing parameters of the melt electrospinning on fiber diameters were investigated. We also studied the fiber formation mechanism from the rods during the laser melt electrospinning process. The following conclusions were reached: (i) coating of EVOH on PLLA rods has a remarkable effect on decreasing fiber diameter from 3 pm to around I pm; (ii) increases in the electric field strength and temperature of spinning space decrease the average diameter of fibers produced from pure PLLA rods, and longer collector distance leads to lager PLLA fiber diameter; and (iii) the migration of PLLA component from the core to the surface of electrospun fibers takes place during the fiber formation process. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 1282-1288, 2009