PLASTIC CO-EXTRUSION APPARATUS WITH SELECTABLE POLYMER FLOW CONTROL AND PRODUCT PRODUCED USING THE APPARATUS

摘要

Co-extrusion apparatus (10) for manufacturing a laminated plastic film or sheet comprises a plug-type layer sequencer (20) including a plurality of channels for conducting a plurality of polymer flows; a transitional aspect ratio block (24) for inducing the plurality of polymer flows to converge; an d a flow velocity profiler cartridge (32) for combining the plurality of polym er flows to form the film. In one embodiment, the layer sequencer includes a tapered selector pin which minimizes mechanical damage when the selector pin is removed. In accordance with another embodiment, the flow velocity profile r cartridge (32) includes inserts fitting within cavities for controlling the polymer flows which form the layers of the film or sheet. At least one such insert defines lanes within an associated cavity so as to promote the formation of lanes of differing polymer composition within at least one laye r of the laminated sheet or film.