Production of cis-1, 4-polybutadiene with a titanium halide-mgr-i catalyst

Claim 1

A PROCESS FOR PREPARING A CIS-1,4-POLYBUTADIENE WHICH COMPRISES CONTACTING 1,3-BUTADIENE IN A HYDROCARBON DILUENT WITH A CATALYST WHICH FORMS ON MIXING COMPONENTS COMPRISING (A) AN ORGANOMAGNESIUM COMPOUND HAVING THE FORMULA R2MG., WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF ALKYL, CYCLOALKYL, ARYL, ALKARYL AND ARALKYL RADICALS, (B) A COMPOUND HAVING THE FORMULA TIXM, WHEREIN X IS SELECTED FROM THE GROUP CONSISTING OF CHLORINE AND BROMINE AND M IS AN INTEGER FROM 2 TO 4, INCLUSIVE, AND (C) IODINE, THE MOL RATIO OF SAID ORGANOMAGNESIUM COMPOUND TO TOTAL TITANIUM IN SAID CATALSYT BEING IN THE RANGE OF 0.75:1 TO 3:1, THE MOL RATIO OF TIXM COMPOUND TO IODINE BEING IN THE RANGE OF 0.5:1 TO 1.25:1, SAID CONTACTING OCCURRING AT A TEMPERATURE IN THE RANGE OF -100 TO 250$F. AND AT A PRESSURE SUFFICIENT TO MAINTAIN THE REACTION MIXTURE IN THE LIQUID PHASE; AND RECOVERING A POLYBUADIENE CONTAINING AT LEAST 90 PERCENT OF CIS-1,4-ADDITION.