| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing foamable polystyrene resin particles by a seed polymerization process to give a foam-molded article having excellent appearance and mechanical strengths.SOLUTION: The method for producing the foamable polystyrene resin particles comprises a first step to add and absorb ≥21 pts.mass and <30 pts.mass of a styrenic monomer based on 100 pts.mass of seed particles to an aqueous medium containing suspended polystyrene resin seed particles, a second step to add a polymerization initiator and the monomer to the aqueous medium to start polymerization reaction of the monomer, and a third step to continuously or intermittently supply the remaining monomer and polymerize the monomer when polymerization conversion of the monomer in the polymerization reaction reaches 75-95%, wherein the monomer is added in the first and the second steps in such a manner that the percentage calculated by (M1+M2)÷(QP+M1+M2)×100 falls within the range of ≥26% and <35% (in the formula, M1 is addition amount of the monomer in the first step; M2 is addition amount of the monomer in the second step; and QP is mass of the seed particle). |
