Polyisobutylene polymerization process having coarse and fine molecular weight control

Claim 1

IN A PROCESS FOR THE PREPARATION OF POLYSIOBUTYLENE WHEREIN ISOBUTYLENE FEED IS POLYMERIZED IN THE PRESENCE OF A SOLID METAL HALIDE DISSOLVED IN A NON-COMPLEX-FORM ING, NON-FREEZING SOLVENT AT A TEMPERATURE FROM -40* TO -150*C. AND WHEREIN THE ISOBUTYLENE FEED CONTAINS A CATALYST POISON IN AN AMOUNT SUFFICIENT TO GIVE A ROUGH CONTROL OVER THE MOLECULAR WEIGHT OF THE POLYMER AT 100% CONVERSION, AND WHEREIN THE ISOBUTYLENE FEED CONTAINS VARYING AMOUNTS OF MATERIALS WHICH LOWER THE MOLECULAR WEIGHT OF THE PRODUCT, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT THE POLYMERIZATION IN THE PRESENCE OF AN ADDED EXCESS OF CATALYST ABOVE THAT NECESSARY TO OBTAIN 100% CONVERSION, CONTINUOUSLY MEASURING THE MOLECULAR WEIGHT OF THE PRODUCT AND CONTINUOUSLY ADJUSTING THE AMOUNT OF EXCESS CATALYST ADDED IN RESPONSE TO CHANGES IN THE MOLECULAR WEIGHT OF THE PRODUCT WHEREBY THE MOLECULAR WEIGHT IS CONTROLLED WITHIN NARROW LIMITS.