Using computational modelling to improve the insight regarding multi-layer polymer flows in co-extrusion

Abstract

Polymer multilayer co-extrusion is a manufacturing process wherein two or more polymers feed a common extrusion die to form a layered product, aiming to combine in a synergic way the properties of the individual polymers comprising each layer [1]. The usual manufacturing approach starts by co-extruding two layers which are duplicated in each Interfacial Surface Generator Module (ISGM) employed, see Figure 1. This is achieved by dividing the flow of the two inlet layers (AB) in the division region, deforming and overlapping the two individual streams, which are subsequently joined in the junction region to reach a 4 layer structure (ABAB) [2]. In this way, each ISGM employed allows duplicating the number of layers in the final product.