The present work demonstrates a simple approach to control microdomains in thermoplastic elastomer by using surfactants based on a good example of polystyrene-b-poly(ethylene-co-1-butene)-b-polystyrene triblock copolymer (SEBS) containing polyethylene glycol lauryl ether (PGLE) electrospun fibers. The interaction between PGLE and the phenyl group of PS in SEBS chain is a key factor to allow PGLE functioning in changing morphology of the SEBS micro-fibers. In general, SEBS electrospun fibers show distorted and fragmented lamellae. By adding only 1 wt%, of PGLE in SEBS, the PGLE retards the microdomain distortion as well as initiates isotropic lamellar orientation. When fiber stretching force reached a certain level, the fragmented lamellar of SEBS-PGLE is initiated, and at that time, the tensile strength of the fibers increases significantly. (C) 2014 Elsevier Ltd. All rights reserved.