EPS (Expandable Polystyrene) is produced by the suspension polymerization method of Styrene Monomer in batch process. Styrene, inorganic and organic inhibitors, demineralized water and various additives are add into the reactors with impellers. Reactors come in various sizes. Suspended Styrene droplets polymerize and turn into Polystyrene. During the polymerization reaction, the reaction is kept under control by heating the reactors from time to time and cooling them from time to time. Later, pentane is added as a blowing agent and penetrated into the beads. The sizes of the EPS granules are adjusted by adding special chemical.
The particles discharged from the reactors pass through the washing tanks and centrifuge type dryers and the water in the product is removed. Then the particles are sent to the sieves to be screened according to their size. Beads screened in the sieve according to their size are transferred to separate silos. Before packaging, beads in silos are coated with special chemicals. During the whole process, the intermediate product is sampled and examined in the laboratory to monitor the operation.