摘要:
A process for simply and inexpensively producing a conjugated diene polymer with a narrow molecular weight distribution and a high cis-bond content at a low cost is provided. The process comprises a polymerization step, wherein a conjugated diene polymer having a cis-1,4-bond content of 98.5 mass % or more and a ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) measured by gel permeation chromatography of 2.5 or less is obtained by carrying out a polymerization reaction in conjugated diene compounds using a catalyst composition containing a rare earth element-containing compound or a reaction product of the rare earth element-containing compound with a Lewis base, an aluminoxane and/or organoaluminum compound, and an iodine-containing compound.
摘要:
A method for producing a modified conjugated diene polymer includes a modification step (A) that subjects a conjugated diene polymer having a cis-1,4-bond content of 98.5% or more and possessing an active end to a modification reaction to introduce an alkoxysilane compound having two or more reactive groups including an alkoxysilyl group into the active end of the conjugated diene polymer, and a condensation step (B) that subjects the residue of the alkoxysilane compound introduced into the active end to a condensation reaction in the presence of a condensation catalyst that includes at least one element among the elements of the groups 4A, 2B, 3B, 4B, and 5B in the periodic table. The method can produce a modified conjugated diene polymer that exhibits low heat build-up and excellent wear resistance.
摘要:
A rubber composition from which a vulcanized rubber suitable for producing, for example, a pneumatic tire having excellent abrasion resistance, breaking strength, rolling resistance, wet skid resistance, and the like can be prepared. The rubber composition comprises a rubber component (A) comprising a diene rubber comprising 20 mass % or more of a modified styrene-butadiene copolymer (a1) and 5 mass % or more of a modified conjugated diene polymer (a2), and a filler (B), wherein the modified conjugated diene polymer (a2) is a conjugated diene polymer obtained by modifying the active terminals of a conjugated diene polymer having a cis-1,4 bond content of 80% or higher, with an alkoxysilane compound, and the filler (B) comprises at least either of 2 to 100 mass parts, relative to 100 mass parts of the rubber component (A), of carbon black (b1) and 30 to 100 mass parts, relative to 100 mass parts of the rubber component (A), of silica (b2).
摘要:
A process for producing a modified conjugated diene polymer includes subjecting an active terminal of a conjugated diene polymer having a vinyl content of less than 10% and a cis-1,4 bond content of 75% or more to a modification reaction with an alkoxysilane compound, and subjecting the alkoxysilane compound (residue) to a condensation reaction in an aqueous solution at a pH of 9 to 14 and a temperature of 85 to 180° C. in the presence of a condensation accelerator including a compound containing titanium. The modified conjugated diene polymer exhibits low heat build-up and increased reinforcing properties when used for a rubber composition, and exhibits excellent wear resistance, mechanical characteristics, and processability.
摘要:
The present invention provides an emulsion composition which has been increased in sulfonic group content, yet has sufficient water resistance and has been enhanced in properties such as small resistance, film-forming property, etc. The emulsion composition contains (A) a water-based solvent, (B) an organic solvent, (C) a sulfonic group-containing polymer soluble in the component (A), and (D) a polymer soluble in the component (B) but insoluble in water. This emulsion composition is enhanced in small resistance and yet has sufficient water resistance and film-forming property.
摘要:
Conjugated diene polymers having good wear resistance, mechanical properties, storage stability, processability and a reduced cold flow are produced by polymerizing a conjugated diene compound with a catalyst of rare earth element compound, a compound containing at least one halogen atom, an aluminoxane, and an organoaluminum compound in an organic solvent and reacting the resulting polymer just after the polymerization with at least one compound selected from the group consisting of a halogenated organometallic compound, a halogenated metal compound, an organometallic compound, a heterocumulene compound, a hetero three-membered-ring containing compound, a halogenated isocyano compound, a carboxylic acid, an acid halide, an ester compound, a carbonic ester compound, an acid anhydride and a metal salt of a carboxylic acid as a modifying agent.
摘要:
A method for preparing a functionalized polymer comprising the steps of preparing a pseudo-living polymer by polymerizing conjugated diene monomer with a lanthanide-based catalyst, and reacting the pseudo-living polymer with at least one functionalizing agent defined by the formula (I) where A is a substituent that will undergo an addition reaction with a pseudo-living polymer, R1 is a divalent organic group, R2 is a monovalent organic group, and each R4, which may be the same or different, is a monovalent organic group or a substituent defined by —OR5 where R5 is a monovalent organic group, with the proviso that A, R1, R2, R4, and R5 are substituents that will not protonate a pseudo-living polymer. Also, the functionalized polymer and a vulcanizable composition containing the polymer.
摘要:
A method for preparing a functionalized polymer comprising the steps of preparing a pseudo-living polymer by polymerizing conjugated diene monomer with a lanthanide-based catalyst, and reacting the pseudo-living polymer with at least one functionalizing agent defined by the formula (I) where A is a substituent that will undergo an addition reaction with a pseudo-living polymer, R1 is a divalent organic group, R2 is a monovalent organic group, and each R4, which may be the same or different, is a monovalent organic group or a substituent defined by —OR5 where R5 is a monovalent organic group, with the proviso that A, R1, R2, R4, and R5 are substituents that will not protonate a pseudo-living polymer. Also, the functionalized polymer and a vulcanizable composition containing the polymer.
摘要:
Disclosed are a method for producing a modified conjugated diene polymer improved in quality stability, more enhanced in low heat buildup and reinforcing ability when used in a rubber composition, excellent in wear resistance, mechanical characteristics and processability, and improved in cold flow; and a rubber composition using the same. The method includes a step of modifying an active end of an active end-containing conjugated diene polymer having a cis-1,4-bond content of 75% or more with an alkoxysilane compound containing at least one functional group selected from the group consisting of (a) an epoxy group, (b) an isocyanate group and (c) a carboxyl group, and a step of adding a condensation accelerator to conduct condensation reaction of the alkoxysilane compound (residue) in an aqueous solution having a pH of 9 to 14 and a temperature of 85 to 180° C.
摘要:
A rubber composition for solid golf balls comprising: (a) 50 to 100 parts by weight of a polybutadiene rubber with a 1,4-cis bond content of 80% or more, a 1,2-vinyl bond content of 2.0% or less, and a ratio (Mw/Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) of 3.5 or less, (b) 0 to 50 parts by weight of a diene-type rubber other than the component(a), provided that the total amount of the component (a) and component (b) is 100 parts by weight, (c) 10 to 50 parts by weight of a cross-linking monomer, (d) 20 to 80 part by weight of inorganic filler, and (e) an effective amount of an organic peroxide. The solid golf balls prepared from the rubber composition provide a good shot feeling, run a long distance, and exhibit superior durability.