An unusual hybrid profile die from Greiner Extrusion US Inc. in Meadville, Pa., combines Celuka PVC foam extrusion technology with free foaming. The Celuka process foams PVC from the outside in, leaving a solid outer skin and inner foam density of 0.62 to 0.65 g/cc (vs. 1.3 to 1.4 g/cc for solid PVC). Free foaming foams from the inside out and produces a cellular outer surface and lower density (0.5 g/cc). The object of combining the two approaches, using chemical blowing agents in both cases, is to eliminate voids and get a dull matte surface. The hybrid die has been tested on window profiles and trim up to about 1 x 1 in. size with densities of 0.55 to 0.60 g/cc. Greiner says several customers have asked for it.
Uniplast International Inc
1101 Morgan Village Rd PO Box 556
Meadville, PA 16335
Phone (814) 333-2060 Fax (814) 333-8142