Investigation on the Controllable Synthesis of Colorized and Magnetic Polystyrene Beads With Millimeter Size via In Situ Suspension Polymerization

A series of colorized and magnetic polystyrene/Fe₃O₄ (PS/Fe₃O₄) composite beads with millimeter size are successfully synthesized by introducing hydrophobic Fe₃O₄ via in situ suspension polymerization of styrene for the first time. Effects of the hydrophobic Fe₃O₄ content, stirring speed, and surfactant dosage on the macromorphology and particle size of PS/Fe₃O₄ beads are systematically investigated to realize the controllable synthesis. Moreover, three kinds of hydrophobic pigments are also employed to synthesize colorized polystyrene, which demonstrates the versatility, simplicity, and wide applicability of the proposed method. Scanning electron microscopy (SEM) and element mapping (EM) images demonstrated that the hydrophobic Fe₃O₄ is well dispersed in the polystyrene matrix. Thermogravimetric analysis (TGA) shows that the resultant PS/Fe₃O₄ beads possess a better thermal stability than neat PS. PS/Fe₃O₄ beads have a promising application in the fields of colorized extruded PS board, colorized expanded PS foam particle, and board.