Since 2002, an unusual die has been pelletizing PLA biopolymer at NatureWorks LLC, Minnetonka, Minn.

Since 2002, an unusual die has been pelletizing PLA biopolymer at NatureWorks LLC, Minnetonka, Minn. It was publically discussed for the first time by Coperion Werner & Pfleiderer, Ramsey, N.J., at Plastics Technology's Bioplastics Processing Conference last month in Charlotte, N.C. The die has a heating channel between every row of die holes-instead of every two rows-for greater heat control. It also uses a rectangular heating slot to increase surface area and heating efficiency because PLA's viscosity is 50 times more temperature-sensitive than that of polyolefins, Coperion notes. Improved wear protection comes from brazing the tungsten carbide die-hole cylinders to each other instead of to the chrome die surface. The latter creates a site for corrosion, Coperion says. Tel: (201) 327-6300 . www.coperion.com

Coperion Corp.
663 E Crescent Ave. Ramsey, NJ 07446
Phone (201) 327-6300 Fax (201) 825-6491