Identification and control of crystallization dynamics during sheet polymer extrusion

Crystallinity control for polymer sheet extrusion processes is considered. An analytical model for the crystallinity dynamics is derived. This development is based on the continuity, momentum, energy and crystallinity equations. It is shown that the crystallinity dynamics can be linearized around a normal operating point. Based on the linearized model, the crystallinity dynamics are identified and a pole placement control law is derived and simulated in order to control the crystallinity around the operating point.