There is disclosed a modified conjugated diene polymer including a structural unit derived from a compound represented by formula (1), and a structural unit derived from a conjugated diene.

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When n is 0, at least two of R.sup.11, R.sup.12, R.sup.13, R.sup.16, R.sup.17 and R.sup.18 are substituted amino groups, and at least one is a hydroxy group or hydrocarbyloxy group.

A method for preparing a functionalized polymer, the method comprising the steps of: (i) polymerizing monomer to form a reactive polymer, and (ii) reacting the reactive polymer with an imine compound containing a heterocyclic group and a hydrocarbyloxy-substituted or silyloxy-substituted aryl group.

A method for preparing a functionalized polymer, the method comprising the steps of: (i) polymerizing monomer to form a reactive polymer, and (ii) reacting the reactive polymer with an imine compound containing a heterocyclic group and a hydrocarbyloxy-substituted or silyloxy-substituted aryl group.

A method for manufacturing a tire rubber composition includes kneading a rubber component, a silane coupling agent and silica such that a content of the silica exceeds 50 parts by mass with respect to 100 parts by mass of the rubber component, adding a vulcanization accelerator to a kneading mixture including the rubber component, the silane coupling agent and the silica, kneading the vulcanization accelerator and the kneading mixture including the rubber component, the silane coupling agent and the silica, adding a vulcanization agent to a resulting mixture including the rubber component, the silane coupling agent, the silica and the vulcanization accelerator, and kneading the vulcanization agent and the resulting mixture including the rubber component, the silane coupling agent, the silica and the vulcanization accelerator such that a kneaded material obtained by the kneading of the vulcanization agent and the resulting mixture has a gel fraction of 30% or less.

An aircraft tire comprises a tread (2), having an axial width L, which comprises a middle portion (3) having an axial width L.sub.C at least equal to 50% and at most equal to 80% of the axial width L of the tread and consisting of a middle rubber composition, and two lateral portions (41, 42), positioned axially on either side of the middle portion (3), each having an axial width (L.sub.S1, L.sub.S2) at least equal to 10% and at most equal to 25% of the axial width L of the tread and each consisting of a lateral rubber composition. The middle rubber composition comprises in particular from 25 to 85 phr of a tin-functionalized butadiene and styrene copolymer and from 15 to 75 phr of isoprene elastomer, and at least one lateral rubber composition is different from the middle rubber composition.

A modified conjugated diene-based polymer, and more particularly, a modified conjugated diene-based polymer having a unimodal molecular weight distribution curve measured by gel permeation chromatography (GPC), molecular weight distribution (PDI; MWD) of less than 1.7, and a Si content of 100 ppm or more based on weight, and a rubber composition including the same.

A method for cleaving a coordinate bond of a complex polymer that contains at least one polymer chain and a plurality of nitrogen- and/or phosphorus-containing functional groups which are bonded to the polymer chain and capable of forming coordinate bonds, wherein the coordinately-bondable nitrogen- and/or phosphorus-containing functional groups form a coordinate bond via a metal ion, characterized in that the method includes dissolving the complex polymer in a solvent containing a free ligand, to cleave the coordinate bond.

The present invention relates to a modification initiator and a modified conjugated diene-based polymer including the same, and more particularly, the present invention provides a modification initiator including a compound represented by Formula 1, a modified conjugated diene-based polymer including the same, and a method of preparing a modified conjugated diene-based polymer.

The present invention relates to a modification initiator and a modified conjugated diene-based polymer including the same, and more particularly, the present invention provides a modification initiator including a compound represented by Formula 1, a modified conjugated diene-based polymer including the same, and a method of preparing a modified conjugated diene-based polymer.

Provided is a modified conjugated diene-based polymer, a rubber composition and a tire with excellent low loss property and durability, and a method of producing a modified conjugated diene-based polymer with which the presently disclosed modified conjugated diene-based polymer can be produced. The modified conjugated diene-based polymer has two or more modifying groups in one modified conjugated diene-based polymer molecule, where the modifying groups between molecules have a non-covalent bond with energy of 10 kJ/mol to 250 kJ/mol. The rubber composition contains the modified conjugated diene-based polymer. The tire uses the rubber composition. The method of producing a modified conjugated diene-based polymer includes (i) anionically polymerizing at least a conjugated diene compound in presence of an alkali metal compound to form a conjugated diene-based polymer, (ii) further adding an alkali metal compound to the conjugated diene-based polymer, and (iii) reacting the product obtained in (ii) with a modifying agent to introduce a modifying group into the conjugated diene-based polymer.