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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.

In the batch emulsion copolymerization of styrene and α- tert -butoxy-ω-vinylbenzyl-polyglycidol macromonomer, carried out at macromonomer concentrations exceeding the critical micelle concentration ( c mc ), particles are formed by a two-step coagulative nucleation mechanism. This mechanism leaves its mark on morphology of particle interface, rate of polymerization and on molecular weight distribution of the obtained polymer. AFM studies revealed that the interface of particles is composed of objects with dimensions close to dimensions of the primary particles. Compartmentalization of styrene in the macromonomer micelles leads to the higher initial rate of styrene conversion than in the similar macromonomer free homopolymerization of styrene. The initial polymerization in the monomer-swollen macromonomer micelles, similar to the microemulsion polymerization, is responsible for the formation of the highest molecular weight component. In the mature particles there are two different polymerization loci: the interfacial layer and the core. This leads to bimodal molecular weight distribution of the formed polymer.