| 摘要 |
PROBLEM TO BE SOLVED: To obtain a styrene-based resin improved in heat resistance and odor, and preferable for food packing containers or the like and to provide its production method. SOLUTION: This heat resistant styrene-based resin is obtained by radical copolymerization of 50-99 wt.% styrene-based monomer, 1-50 wt.% (meth)acrylic acid monomer and 0-20 wt.% other copolymerizable monomer and has <=1,000 ppm total content of the unpolymerized above monomers, preferably <=1,000 ppm (meth)acrylate content and <=2,000 ppm sum of styrene dimer and trimer content. Its production method comprises the following steps; 0.01-5 pts.wt. multifunctional organic peroxide or >=2 kinds of mono-functional ones are added to 100 pts.wt. monomers, polymerization temperature is controlled to <120 deg.C till conversion reaches >=50%, then increased to >=125 deg.C. |
