Vapor phase synthesis of rubbery polymers

Abstract

By utilizing the vapor phase polymerization techniques of the present invention, numerous distinct and highly beneficial advantages are realized. For instance, cis-1,4-polyisoprene rubber and high cis-1,4-polybutadiene rubber having a consistent and controllable molecular weight can be easily and practically prepared without utilizing a solvent. The subject invention more specifically discloses a method for vapor phase polymerizing isoprene into cis-1,4-polyisoprene in a process comprising the steps of: (1) charging into a reaction zone said isoprene and a preformed catalyst system which is made by reacting an organoaluminum compound with titanium tetrachloride, preferably in the presence of at least one ether; wherein the isoprene is maintained in the vapor phase in said reaction zone by a suitable combination of temperature and pressure; (2) allowing said isoprene to polymerize into cis-1,4-polyisoprene in said reaction zone at a temperature within the range of about 0.degree. C. to about 100.degree. C. in the presence of a diarylamine, wherein said reaction zone is a horizontal, stirred reactor of substantially circular cross section containing a centrally-located drive shaft extending longitudinally through said reactor to which are attached a plurality of adjacently located paddles, which paddles cause essentially no forward or backward movement of the cis-1,4-polyisoprene contained in said reactor; and (3) withdrawing said cis-1,4-polyisoprene from said reaction zone.