Continuous process for the preparation of block copolymers

Claim 1

AN IMPROVED POLYMERIZATION PROCESS FOR MINIMIZING GEL FORMATION IN THE PRODUCTION OF BLOCK COPOLYMERS WHICH COMPRISES CONTINUOUSLY INTRODUCING INTO A POLYMERIZATION ZONE A REACTION MIXTURE OF (A) 1,3-BUTADIENE AND STYRENE, (B) A HYDROCARBON DILUENT SELECTED FROM THE GROUP CONSISTING OF PARAFFINS, CYCLOPARAFFINS AND AROMATIC HYDROCARBONS HAVING FROM 3 TO 12 CARBON ATOMS PER MOLECULE, (C) 0.07 TO 2 PARTS PER 100 WEIGHT PARTS OF TOTAL MONOMERS OF AN INITIATOR CONSISTING ESSENTIALLY OF AN ORGANOLITHIUM INITIATOR HAVING THE FORMULA (R(LIE)X, WHEREIN R IS A HYDROCARBON RADICAL SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC, CYCLOALIPHATIC AND AROMATIC RADICALS CONTAINING UP TO AND INCLUDING 20 CARBON ATOMS PER RADICAL, AND X IS AN INTEGER FROM 1 TO 4, INCLUSIVE, AND (D) 0.1 TO 3 MOLS OF AN ALKYL HALIDE COMPOUND PER MOL OF INITIATOR, SAID HALIDE HAVING FROM 1 TO 12, INCLUSIVE, CARBON ATOMS PER MOLECULE, CONTINUOUSLY CONTACTING SAID REACTION MIXTURE WITHIN SAID ZONE AT A TEMPERATURE WITHIN THE RANGE 0 TO 300*F. AND UNDER LIQUID PHASE CONDITIONS TO FORM SAID COPOLYMER, AND CONTINUOUSLY WITHDRAWING FROM SAID ZONE SAID BLOCK COPOLYMER AS A PRODUCT OF THE PROCESS.