GB787047A - Method and apparatus for preparing polyisobutylene - Google Patents

Abstract

<PICT:0787047/IV (a)/1> <PICT:0787047/IV (a)/2> Polyisobutylene or a copolymer of isobutylene with isoprene or butadiene is recovered from Friedel-Crafts polymerization processes which form a cold suspension of solid polymer particles in a diluent, by discharging the suspension through a nozzle into a plurality of converging streams of steam, to disperse the particles which are then contacted with water to form a dispersion. In an example, polyisobutylene of high molecular weight, e.g. 200,000 to 500,000, is prepared in a diluent, e.g. methyl chloride or a lower alkane, at -100 DEG to -160 DEG F., using as catalyst aluminium chloride in methyl chloride and the suspension discharged through pipe 9 (Fig. 1) into a hot water flash tank 16 containing zinc or sodium stearate as slurrying agent at a pH of 8.5 to 9.5. Steam is introduced through pipe 11 into a jacket 14 (Fig. 2) around the effluent tube 9, and is directed through nozzles 15 to strike the effluent at converging angles while water is introduced through pipe 13 at a tangent so that the swirl around jacket 12 carries the dispersed polymer and unflashed methyl chloride to drum 16, from which dispersion is withdrawn at 18 (Fig. 1) or recirculated through pipe 13, while vaporized materials are withdrawn at 17 and recycled.