Coextrusion feedblock and process

摘要: A feedblock fashioned from a plurality of plates is disclosed which distributes two flows dissimilar synthetic resinous materials into radially stratified annular form for extrusion by pipehead die. The mounted on with the defining material flow channels three strata. Independently operable valves vary stratum thickness and assure matched conditions between strata at confluence. Each independently accelerated through convergent channel to that uniform circumferential distribution develops. Moreover, are developed systems do not induce maldistribution. third handled eliminate Accordingly, process apparatus develop stable radial stratification having neither nor maldistributions may later interact distort