HIGHLY PURE POLYSTYRENE, METHOD FOR PREPARING THE SAME AND DISPOSABLE FOOD CONTAINER USING THE SAME

摘要

The present invention relates to a process for preparing highly pure polystyrene for food container having a number-average molecular weight of from 10,000 to 1,000,000, and a polydispersity of from 1.1 to 20, styrene dimer content of less than 50ppm and styrene trimer content of less than 500ppm. The polystyrene is produced by an anionic polymerization, and the anionic polymerization is carried out by adding a styrene monomer, a solvent whose amount is more than 100 weight part to 100 weight part of the monomer and an initiator whose amount is from 0.01 to 1 mol part to 100 mol part of the monomer to initiate polymerization of the monomer into a batch-wise or a continuous-wise reactor, and reacting them at a reaction temperature of 10 SIMILAR 160 DEG C and, wherein the initiator is added in two or more steps.