Process for the production of liquid butadiene polymers

Claim 1

IN A PROCESS FOR THE PRODUCTION OF GEL-FREE LIQUID POLYBUTADIENE POLYMERS HAVING AN AVERAGE MOLECULAR WEIGHT OF 500 -10.000 AND A VISCOSITY OF 50-50,000 CPS MEASURED AT 20*C IN THE HEOPLER FALLINGBALL VISCOMETER ACCORDING TO HAAKE, AND 30-90 PERCENT CISDOUBLE BONDS, 10-70 PERCENT TRANS-DOUBLE BONDS AND LESS THAN 5 PERCENT VINYL DOUBLE BONDS, AT LEAST 90 PERCENT OF THE DOUBLE BONDS BEING CENTRALLY POSITIONED, WHICH PROCESS COMPRISES POLYMERIZING 1,3-BUTADIENE IN AN INERT DILUENT AND IN THE PRESENCE OF A NEGLIGIBLE QUENTITY OF LESS THAN 2 PERCENT BY WEIGHT OF OXYGEN AND WATER BASED ON THE AMOUNT OF CATALYST WITH A CATALYTIC AMOUNT OF A MIXED CATALYST COMPRISING A. AT LEAST ONE DILUENT-SOLUBLE ORGANONICKEL COMPOUND SELECTED FROM THE GROUP CONSISTING OF NICKEL OCTOATE, NICKEL OLEATE, NICKEL ACETYLACTONATE, NICKEL TETRACARBONYL, NI(O)BIS-CYCLOOCTADIENE, DIALKYLNICKEL AND DICYCLOPENTADIENYL-NECKEL, AND B. AN ALKYLALUMINUM SESQUIHALIDE HAVING 1-2 CARBON ATOMS IN THE ALKYL GROUP, IN A MOLAR RATIO OF THE NICKEL COMPOUND A) TO THE ALUMINUM COMPOUND B) OF 1:4 TO 1:50, THE IMPROVEMENT WHICH COMPRISES: CONDUCTING THE POLYMERIZATION IN THE PRESENCE OF A MOLECULAR WEIGHT REGULATING AMOUNT OF 1-15 PERCENT BY WEIGHT ETHYLENE OR ABOUT 30 PERCENT BY WEIGHT PROPYLENE AT A TEMPERATURE OF 10*-180*C PRODUCE SAID LIQUID POLYBUTADIENE POLYMER.