Abstract: In this paper, the formation of corrugation during the processing of foam sheet was analyzed by combining bubble nucleation with growth theory. The accuracy of simulation was also experimentally verified in foam extrusion. It was found that the number of corrugation first increased and then decreased with decreasing die gap. A conclusion was drawn that increasing zero shear viscosity and relaxation time of polymer melt could decrease the amount of corrugations.

Key words: foam extrusion, bubble nucleation, bubble growth, corrugation simulation