EXPANDED STYRENE RESIN SHEET HAVING LOW CONTENT OF LOW- MOLECULAR WEIGHT COMPONENT

摘要

PROBLEM TO BE SOLVED: To solve the problems of conventional expanded styrene resin sheet caused by low-molecular components such as styrene monomer and styrene oligomer comprising the adhesion of the low-molecular component to a mold or a processing machine and the staining of the surface of a molded article in the production of the sheet or in the fabrication of a food tray or food container from the expanded sheet and the lowering of various properties, especially printability and rigidity in hot state.;SOLUTION: Anionic polymerization of styrene using an organolithium initiator can remarkably suppress the residue of unreacted styrene monomer and the formation of styrene oligomer under a polymerization condition within a specific range. The objective expanded sheet free from the above problems is produced by using the styrene resin obtained by the polymerization method and has a low-molecular content of 1,000 ppm.;COPYRIGHT: (C)2001,JPO