| 摘要 |
PROBLEM TO BE SOLVED: To provide expandable polystyrenic resin particles for a heat insulating material suitably used for an automobile interior material, which can eliminate the use of hexabromocyclododecane, exhibit excellent flame retardancy and thermal insulation property, excel in no expansion-shrinkage due to a temperature change (dimensional stability), excel in environmental sanitation because of a small amount of volatilizing organic compounds, and give a molded foam product which achieves good heat fusion and excels in environmental sanitation because of a small amount of volatilizing organic compounds, and to provide an automobile interior material.SOLUTION: Polystyrenic resin particles are dispersed in an aqueous suspension, and before or during impregnating a blowing agent, a flame retardant solution prepared by dissolving 40-300 pts.wt. of a 2,2-bis[4-(2,3-dibromoalkoxy)-3,5-dibromophenyl]-propane as a bromine-based flame retardant in 100 pts.wt. of a plasticizer having a solubility parameter (SP) of 8.3-9.4 is fed into the aqueous suspension and the flame retardant is impregnated into the polystyrenic resin particles. The resulting expandable polystyrenic resin particles are pre-expanded and the pre-expanded particles are filled into a mold and expanded to obtain a molded polystyrenic foam product having an average chord length of 40-150 μm. |
