The results show that the extensional flow of melt in convergent die results in intense entrance elastic effect and distinct extrusion swell in conical die with different angles.
The research advances about die swell, the reduction of friction between die wall and polymer melt, wall slip and melt fracture in polymer extrusion are described in the paper.
The extrudate swell behaviour and the factors affecting it during short die extrusion of linear low density polyethylene (LLDPE) melt have been investigated by using a rheometer.