This paper describes the preparation of spheroidal polystyrene core and polyglycidol-rich microparticles by stretching the relevant core-shell microspheres embedded into the poly(vinyl alcohol) film. The requirements for the preparation of the defect-free core-shell spheroids were determined. The rearrangement of the microparticle interfacial layer accompanying the conversion of the microspheres into microspheroids is described. (C) 2018 Elsevier Ltd. All rights reserved.