Diethyleneglycol methylethermethacrylate(MeO2MA) and oligoethylene glycol methylethermethacrylate(OEGMA) are polymerized on polythiophene(PT) backbone to produce water-soluble PT-g-PMeO2MA(PTD) and PT-g-P(MeO2MA-co-OEGMA)(PTDO) using atom transfer radical polymerization. They are characterized by 1H NMR and GPC techniques. TEM micrographs indicate that PT-chains self-organize as nanospheres, and atomic force micrographs suggest that aggregated PT-chains are present at the centre surrounded by dispersed PMeO2MA fibers producing miceller-type aggregates. Dynamic light scattering study indicates an initial decrease followed by sharp increase of Z-average particle size of PTD with temperature for attaining lower critical solution temperature (LCST) at 20 degrees C. The LCST increases with OEGMA concentration in PTDO. The temperature dependent PL emission of PTD shows a minimum at 19 degrees C, followed by a sharp increase till 21 degrees C, and in the cooling cycle, it shows a complete reversibility. In the PTDO copolymers, the PL intensity shows the hike at progressively higher temperatures due to the increase of LCST with increasing OEGMA concentration. (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013