A new approach to making EPS pellets for bead foam molding uses an extruder in place of a continuous polymer reactor. Last year, Sulzer Chemtech in Switzerland (U.S. office in Tulsa, Okla.) sold the first developmental extrusion system to mix PS and blowing agent, blend the two with static mixers, cool the melt, and underwater pelletize it into unexpanded EPS pellets. These look different from round EPS beads, which are made in a batch reactor process, but the pellets can be pre-expanded and foamed in standard EPS shape molding equipment, according to Sulzer. (918) 4456636 • www.sulzer.com
Sulzer Chemtech USA
4019 S. Jackson Ave. Tulsa, OK 74107
Phone (918) 445-6672 Fax (918) 445-6670
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