| 摘要 |
PURPOSE:To economically produce (expandable) styrene-based resin particles having a desired particle diameter in high yield by adding a styrene-based monomer and polymerization initiator to an aqueous medium and carrying out suspension polymerization in the presence of styrene-based resin particles having a fine particle diameter. CONSTITUTION:(A) Styrene-based resin particles having a smaller particle diameter than that of desired styrene-based resin particles, preferably <=0.8mm, e.g. unnecessary particles, which cannot be converted into products and have a small particle diameter are dispersed in an aqueous medium to provide a dispersion. (B) A styrene-based monomer, a polymerization initiator, optionally a dispersing agent, etc., are added to an aqueous medium and the resultant mixture is stirred and dispersed using a homomixer, etc., to afford a dispersion in which the droplet particle diameter of the aforementioned monomer therein is smaller than that of the resin particles in the component (A). The obtained dispersion is then added to the aforementioned dispersion and suspension polymerization is carried out. Alternatively, a foaming agent is impregnated during or after the polymerization to produce (expandable) styrene-based resin particles. |
