Process for production of high-isoprene butyl rubber

Abstract

The present invention relates to a process for producing polymers comprising repeating units derived from at least one isoolefin monomer, at least one multiolefin monomer and optionally further copolymerizable monomers in the presence of at least one organic nitro compound and AlCl 3 /water wherein the process is conducted in the absence of compounds selected from the group consisting of vanadium compounds, zirconium halogenid, hafnium halogenides. Preferably the polymers have a multiolefin content of greater than 2.5 mol %, and a molecular weight M w of greater than 240 kg/mol.

1 . A polymer having repeating units derived from at least one isoolefin monomer, at least one multiolefin monomer and, optionally, further copolymerizable monomers prepared by providing at least one isoolefin monomer, at least one multiolefin monomer, and, optionally, further copolymerizable monomers; and
 polymerizing the at least one isoolefin monomer, at least one multiolefin monomer, and, optionally, further copolymerizable monomers in the presence of from 5 to 500 ppm of at least one organic nitro containing compound or H—NO 2  and AICI 3 /water in the absence of compounds selected from the group consisting of vanadium compounds, zirconium halogenid, and hafnium halogenides.   
   
   
       2 . The polymer of  claim 1 , wherein the multiolefin content is greater than 2.5 mol. %. 
   
   
       3 . The polymer of  claim 1 , wherein the multiolefin has a M w  of greater than 240 kg/mol.