Polystyrene nanocomposites produced by melt-compounding with polymer-coated magnesium carbonate nanoparticles

Nanocomposites composed of PS and surface-coated MgCO ₃ were produced by melt-compounding in a laboratory kneader. The amphiphilic acrylate copolymer-coated MgCO ₃ particles were produced by inverse emulsion polymerization and added up to 5 wt.% into PS. The dispersion of the MgCO ₃ in PS was studied by SEM and AFM techniques, respectively, and discussed. The mechanical and thermo-mechanical properties of the nanocomposites were determined in short-time creep, uniaxial static tensile tests DMA and TGA. It was found that the lower the MgCO ₃ content, the finer the dispersion of the related particles. Incorporation of surface-coated nano-scaled MgCO ₃ in PS increased the resistance to creep, enhanced the tensile strength, E-modulus (stiffness), and HDT. However, the elongation at break of PS nanocomposites was reduced compared to the neat PS. The tensile strength and TGA behavior of the nanocomposites were markedly affected by the dispersion quality of the nanoparticles.