| 摘要 |
PROBLEM TO BE SOLVED: To produce expandable styrene-based polymer particles by minimizing the amount of produced fine particles (<0.5mm particle diameter), improving the yield thereof and regulating the cell size within a suitable range (50-150μm) for preexpanded particles and thereby obtain an expansion molding excellent in quality characteristics by satisfying performances thereof from a laboratory to a mass-production scales without any regard to the size of the production scale. SOLUTION: Tricalcium phosphate in an amount of 0.01-0.1 pt.wt. based on 100 pts.wt. styrene-based monomer is synthesized in an aqueous medium by adding trisodium phosphate and calcium chloride thereto and the styrene- based monomer, together with a dodecylphenyl oxide disulfonate which is a dispersion assistant, is then added to carry out the suspension polymerization. The interiors of the produced polymer particles are impregnated with a foaming agent to thereby produce expandable styrene-based polymer particles. |
