Insight into the structure of polystyrene-poly(methyl methacrylate) core-shell particles synthesized by seeded suspension polymerization

Abstract

Core-shell particles were synthesized employing seeded suspension polymerization. Suspension polystyrene (PS) particles were used as seeds, and poly(methyl methacrylate) (PMMA) was synthesized in the presence of polystyrene seeds. A combination of solvent extraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy techniques were employed to study the structure and morphology of synthesized particles. The results suggested a core-inner shell-outer shell structure for the synthesized particles in which the PS core was covered by a PMMA-rich inner shell and a very thin PS-rich outer shell. The size and concentration of PMMA domains decreased from the outer shell toward the core of the particle, and particle morphology was mainly controlled by the limitations to the diffusion of MMA through the polymer particle.

Synthesis of Crosslinked Microparticles Based on Glycidyl Methacrylate and N‐Vinylimidazole

“…The stabilizing properties of various types of stabilization systems are influenced by their chemical structure, molecular mass as well as by the balance between the strongly polar groups which determine the solubility of the stabilizer in water and the number of hydrophobic groups, which physically interact with the surface of the monomer droplets. [ 45 ] The stabilization system affects particle size, controls the coalescence process and facilitates the drop breakup by reducing the interfacial tension. In this study, the influence of the composition of the stabilization system on the reaction yield, surface morphology, the parameters of the porous structure and the size distribution was performed by modifying the composition of stabilization systems, keeping constant the following parameters: molecular mass and hydrolysis degree of PVA (52650 g mol −1 , 88%), monomer ratio (GMA:NVI:TEGDMA = 40:30:30), dilution ( D = 0.5), porogenic agent (toluene), and stirring speed (300 rpm) ( Table 3 and Figure ).…”