Patent ID: 6525149
Filing Date: 2003-02-25
Classification: B01J,C08F,Y10S

Abstract:
A liquid phase polymerization process for preparing a polyolefin product having preselected properties, said process comprising:providing a liquid feedstock comprising at least one olefinic component; providing a catalyst composition comprising a stable complex of BF3 and a complexing agent therefor; introducing said feedstock and said catalyst composition into a residual reaction mixture in a loop reactor reaction zone; recirculating the residual reaction mixture in said zone at a recirculation rate sufficient to cause intimate intermixing of the residual reaction mixture, the feedstock and the catalyst composition to thereby present a recirculating, intimately intermixed reaction admixture in said reaction zone; maintaining the recirculating intimately intermixed reaction admixture in its intimately intermixed condition and removing heat of reaction from the reaction admixture at a rate calculated to provide a substantially constant reaction temperature in the reaction admixture while the same is recirculating in said reaction zone, said constant reaction temperature being at a level appropriate for causing olefinic components introduced in said feedstock to undergo polymerization to form said polyolefin product in the presence of said catalyst composition; withdrawing a product stream comprising said polyolefin product from said reaction zone; and controlling the introduction of said feedstock into said reaction zone and the withdrawal of said product stream from the reaction zone such that the residence time of the olefinic components undergoing polymerization in the reaction zone is appropriate for production of said polyolefin product, wherein the reaction admixture is continuously recirculated at a first volumetric flow rate, and said feedstock and said catalyst composition are continuously introduced at a combined second volumetric flow rate, and wherein the ratio of said first volumetric flow rate to said second volumetric flow rate ranges from about 20:1 to about 50:1.