Effect of Process and Material Parameters On Interlayer Peel Strength in Coextrusion Coating, Film Casting and Film Blowing

Abstract

Peel strength between layers in coextruded cast film and extrusion coating is found to increase with increasing process time, defined as the time between the die exit and when the polymer is quenched. The results suggest that adhesion is limited by the time and temperature available for bonding after new interfacial area is created during drawing. This contrasts with previous work in blown film where increases in peel strength with process time were attributed primarily to stress effects. The results from both processes, however, were found to collapse onto a single master curve by multiplying the peel strength by a function of the tie resin modulus and dividing the process time by the tie resin relaxation time.