Polyisobutene prepared with reaction medium with low diluent content

Abstract

A process for the preparation of polyisobutylene polymers in a circulating loop reactor having one or more reaction tubes in contact with a heat transfer medium, comprising the steps of: (a) feeding a feed consisting essentially of polymerizable monomers and a catalyst The mixture is fed into the residual reactor stream at a feed rate to form a reaction mixture comprising less than 5% by weight of the diluent component; (b) utilizing a circulation pump operating at a differential pressure ΔP corresponding to the circulation flow , the reaction mixture is circulated at a circulation rate greater than the feed rate in one or more reaction tubes of the loop reactor; (c) the reaction mixture is circulated in one or more reaction tubes of the loop reactor or multiple tubes to convert said feed mixture into polyisobutylene polymer while cooling one or more tubes of said loop reactor with said heat transfer medium; and (e) from said loop Polyisobutylene polymer was withdrawn from the reactor.

Description

[0001] Cross References to Related Applications [0002] This application is based on US Provisional Application 61 / 551,576 filed on October 26, 2011 with the same title. Priority is hereby claimed from provisional application 61 / 551,576, the disclosure of which is hereby incorporated by reference in its entirety. technical field [0003] The present invention relates to the preparation of polyisobutene by cationic polymerization in a reaction medium with a low diluent content, characterized by high speed and increased circulation rate in a loop reactor operated with a relatively high pressure drop across the circulation pump and turbulence. Background technique [0004] Methods of cationic polymerizing olefins are known in the art. US Patent 6,858,690 to Webb et al. discloses a process for making butyl rubber in which processing efficiency, including heat transfer, is improved through the use of tertiary halogen initiators. See also, US Patent No. 3,932,371 to Powers, wh...

AI Technical Summary

Problems solved by technology

[0019] Prior art systems are characterized by diluent levels in the reaction mixture of 10% by weight or more, typically 50% by weight diluent or more, require solvent recovery and / or involve high solvent costs

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