Modified conjugated diene polymer and process for production thereof

Abstract

A process for producing a modified conjugated diene polymer which comprises the steps of (I) polymerizing a conjugated diene in an inert organic solvent in the presence of a catalyst comprising (a) a lanthanum series rare earth element compound, (b) an organoaluminum compound represented by the general formula, Alr.sup.1 R.sup.2 R.sup.3 (wherein R.sup.1, R.sup.2 and R.sup.3 which may be same or different, are hydrogen atoms or hydrocarbon groups of 1 to 8 carbon atoms and at least one of R.sup.1, R.sup.2 and R.sup.3 is said hydrocarbon group) and, if necessary, at least one member selected from the group consisting of (c) a Lewis acid and/or (d) a Lewis base, and then (II) modifying the resulting reactive polymer with a modifying compound selected from the group consisting of the following components (e), (f) and (g): (e) an organometal halide compound represented by the general formula, R.sub.n .sup.4 MX.sub.4-n (wherein R.sup.4 is an alkyl group of 1 to 20 carbon atoms or an aryl group, M is a tin or germanium atom, X is a halogen atom, and n is an integer of 1 to 3), (f) a heterocumulene compound or a three-membered heterocyclic compound having, in the molecule, a bond represented by the general formula, ##STR1## (wherein X.sup.1 is a carbon, nitrogen, oxygen or sulfur atom, Y is a carbon or sulfur atom, Z is a nitrogen, oxygen or sulfur atom, and X.sup.2 is a nitrogen, oxygen or sulfur atom), and (g) a halogen compound having, in the molecule, a bond represented by the general formula, ##STR2## (wherein Y.sup.1 is a nitrogen or oxygen atom and X is a halogen atom). Said modified conjugated diene polymer has excellent characteristics in wear resistance, heat generation, mechanical properties, etc.

Dependencies are inferred from the claim text.