Process for controlled polymerization of stereospecific alpha-olefins having preselected isotacticity

Abstract From the Canadian patent

A method and system for controlling and maintaining relatively constant the desired isotacticity of polypropylene produced by a reactor system employs a model which correlates isotacticity values to catalyst productivity values. The model is generated from empirical data of the reactor system. A particular catalyst productivity target value is then calculated from the model corresponding to a desired level of isotacticity selected for the product. The instantaneous catalyst productivity of the system is then determined and compared to the catalyst productivity target value. When the comparison between the instantaneous catalyst productivity value and the catalyst productivity target value …