Synthesis of crosslinked polymer nanoparticles suitable for the formation of nanolayer organic films

Free radical crosslinking copolymerization of styrene and ethylene glycol dimethacrylate (n_ST/n_EGDM in feed = 5/5) has been investigated in toluene. Variation of the reaction conditions allows the formation of macromolecules with low molecular weight (21.6 kDa and 12 nm in diameter), perfectly soluble branched particles in the early stage of the polymerization. Elongation of the reaction time leads to the formation of soluble/swelling microgels with medium molecular weight (156 kDa and 41–120 nm) and, finally, swelling/particularly soluble colloidal polymer particles with very high molecular weight (3.6 MDa and 59–324 nm). Conversion, molecular weight [by gel permeation chromatography (GPC)], ratio of pendant vinyl groups [by nuclear magnetic resonance (NMR)], size of nanoparticles in swollen [by dynamic light scattering (DLS)] and dried state [by transmission electron microscopy (TEM)], morphology [by scanning electron microscopy (SEM)], and nanolayer film formation (by SEM) were measured. The role of reaction conditions in producing different polymer structures and morphologies was demonstrated.