Influence of the calendering step on the adhesion properties of coextruded structures

Copyright 2012 Carl Hanser Verlag. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the Carl Hanser Verlag. The authors are grateful to the publisher, Carl Hanser Verlag, for letting the manuscript being archived in this Open Access repository. The final publication is available at http://www.polymer-process.com/IPP2516International audienceThe coupled coextrusion calendering process of multilayer thermoplastic sheets has been studied. The structure of the film has been observed, the density of chemical links at the interface and the adhesion between the coextruded layers have been measured. There are some controversial features about the influence of calendering parameters. Several models of increasing complexity are proposed to master the process and its influence on adhesion. A multilayer thermal model accounting for the crystallization kinetics of both polymers allows defining qualitatively the temperature field especially at the interface between the two layers. A multilayer thermo- mechanical model provides quantitative figures on the stress, shear, elongation and temperature fields in the coextruded film and especially at the interface. Relationships between these parameters, density of chemical links at the interface, crystalline structure of the sample and peeling forces are discussed