Patent ID: 6884858

Claim:
A single-stage 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 complex of BF 3 and a complexing agent therefor, said complexing agent comprising a glycol or an aliphatic alcohol having a primary hydroxyl group and no hydrogen on a beta carbon, said complex being stable at temperatures needed to produce said polyolefin product; introducing said feedstock and said catalyst composition into a residual reaction mixture in a loop reactor reaction zone, said reaction zone comprising a tube side of a shell-and-tube heat exchanger; recirculating the residual reaction mixture with the feedstock and the catalyst composition therein in said zone at a recirculation rate sufficient to establish a Reynolds number of at least about 2000 in the zone and thereby cause intimate intermixing of the residual reaction mixture, the feedstock and the catalyst composition to thereby present a recirculating, intimately intermixed reaction admixture of the residual reaction mixture, the feedstock and the catalyst composition 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 polyolefin product and catalyst composition from said reaction zone; adding a quenching material capable of killing the catalyst to the withdrawn product stream; and controlling the introduction of said feedstock into said reaction zone and the withdrawal of said product stream from the reaction zone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.