Electrospinning of styrene-isoprene copolymeric thermoplastic elastomers

Abstract

In the present contribution, electrospinning of two chemically distinct thermoplastic elastomers based on block copolymers of styrene and isoprene [i.e., multi-armed poly(styrene-b-isoprene) (PS-PI) and linear poly-(styrene-b-isoprene-b-styrene) (PS-PI-PS)] was reported for the first time. Either 1,2-dichloroethane or chloroform was used as the solvent. The effects of solution concentration, solvent, applied electrical potential, chemical structure of the thermoplastic elastomers, and solution feed rate on morphological appearance and/or size of the as-electrospun products were investigated mainly by means of scanning electron microscopy (SEM). The electrospinnability of the polymer solutions was found to increase with increasing solution concentration. The size of the as-spun products from PS-PI solutions in 1,2-dichloroethane was consistently smaller than that of the products from the solutions in chloroform. The increase in the applied electrical potential caused the size of the as-spun products from both types of the polymer solutions to decrease monotonously or decrease with initial increase in the applied potential, reach a minimum at an intermediate value, and increase with further increasing applied potential. Despite the difference in the chemical structure of the two elastomers, the viscosity of their solutions in 1,2-dichloroethane was essentially similar, but the size of the as-spun products from PS-PI solutions was consistently larger than that of the products from PS-PI-PS solutions. © 2006 The Society of Polymer Science.