摘要:
An alkenyl aromatic compound-conjugated diene block copolymer having a combined alkenyl aromatic compound content of 25-95% by weight, characterized in that said copolymer is represented by the formula,A--B--Awherein A represents an alkenyl aromatic compound polymer block, the total amount of A's in both ends being 50-97% by weight of the total combined alkenyl aromatic compound content; B represents a conjugated diene-alkenyl aromatic compound copolymer block, said B portion having (a) 2-10 taper blocks where the amount of the alkenyl aromatic compound increases gradually and (b) a weight ratio of alkenyl aromatic compound/conjugated diene of 3-85/97-15; and the total amount of the chains that 1-4 alkenyl aromatic compound monomers are linked is 5-30% by weight of the total combined alkenyl aromatic compound content. Said copolymer is excellent in the balance of impact strength, tensile strength and elongation.
摘要:
A branched styrene-butadiene copolymer and a pneumatic tire using the same as a tread base rubber are disclosed. This copolymer is produced by coupling an active styrene-butadiene copolymer anion, which is obtained by polymerizing styrene and butadiene in a hydrocarbon solvent in the presence of ether or a tertiary amine and an initiator of an organolithium compound, with a tin halide compound. In the copolymer, the ratio of branched copolymer connected with tin-butadienyl bond is at least 20% by weight, and the content of bound styrene is not less than 3% by weight but less than 25% by weight, and the content of vinyl bond in butadiene portion is not less than 30% but less than 50%.
摘要:
A styrene-butadiene copolymer having a high styrene content is disclosed, which is obtained by polymerizing styrene and butadiene in a hydrocarbon solvent in the presence of an organolithium compound and, if necessary, a Lewis base and then coupling with a tin halide compound. This copolymer contains in its main chain at least 30 wt % of polymer having a tin-carbon bond and has a bound styrene content of more than 25 wt % but not more than 60 wt % and a content of vinyl bond in butadiene portion of not less than 30% but less than 50%.
摘要:
A branched styrene-butadiene copolymer and a pneumatic tire using the same as a tread base rubber are disclosed. This copolymer is produced by coupling an active styrene-butadiene copolymer anion, which is obtained by polymerizing styrene and butadiene in a hydrocarbon solvent in the presence of ether or a tertiary amine and an initiator of an organolithium compound, with a tin halide compound. In the copolymer, the ratio of branched copolymer connected with tin-butadienyl bond is at least 20% by weight, and the content of bound styrene is not less than 3% by weight but less than 25% by weight, and the content of vinyl bond in butadiene portion is not less than 30% but less than 50%.
摘要:
A butadiene-base polymer containing a branched polymer through tin-carbon bond and a process for producing the same are disclosed. The butadiene-base polymer is produced by polymerizing 1,3-butadiene alone or 1,3-butadiene and aromatic vinyl compound in a hydrocarbon solvent in the presence of a Lewis base using an organolithium compound as an initiator and then coupling with a tin halide, and satisfies the following requirements:(1) a content of a bound aromatic vinyl compound in the butadiene-base polymer is 0-40% by weight;(2) a ratio of vinyl bond-containing butadiene unit in the toal butadiene unit of the butadiene-base polymer is 30-90%;(3) a ratio of the branched polymer in the butadiene-base polymer is at least 30% by weight; and(4) a ratio of a component having a molecular weight of less than 100,000 as polystyrene in the molecular weight distribution as measured by a gel permeation chromatography is 10-20% by weight.
摘要:
A cyclic olefin addition copolymer obtained by copolymerizing a cyclic olefin compound having a side chain substituent group with a ring structure, such as endo-tricyclo[4.3.0.12,5]deca-3,7-diene or endo-tricyclo-[4.3.0.12,5]deca-3-ene, with another cyclic olefin compound such as bicyclo[2.2.1]hept-2-ene, and further with a cyclic olefin compound having a hydrolysable silyl group as needed, or hydrogenating after copolymerization; a composition for crosslinking in which a specific crosslinking agent is incorporated; a crosslinked product obtained by crosslinking the composition; an optical material containing the copolymer, the composition or the crosslinked product; and a method for producing the copolymer in which addition polymerization is conducted using a specific nickel catalyst.
摘要:
A butadiene-based rubber composition is disclosed, which contains not less than 20% by weight of a butadiene-based homopolymer or copolymer having a glass transition temperature (Tg) of not less than -105.degree. C., but less than -70.degree. C. and a Mooney viscosity (ML.sub.1+4, 100.degree. C.) of 10 to 150. The butadiene-based homopolymer or copolymer is obtained by polymerizing butadiene or random-copolymerizing butadiene with at least one kind of a monomer selected from the group consisting of another conjugated diene and an aromatic vinyl compound, and then reacting polymerization-active terminals thereof with an isocyanate compound and/or an isothiocyanate compound. The butadiene-based rubber composition has excellent resilience, fracture strength, and wear resistance as a vulcanizate as well as excellent processability as an unvulcanized rubber, and can be used as tire applications such as tire treads, undertreads, sidewalls, bead portions, etc. as well as vibration insulating rubber, hoses, belts and other industrial articles.
摘要:
A rubber composition for use in tire is disclosed which contains at least 30% by weight, relative to the entire rubber component, of a conjugated diene-monovinyl aromatic hydrocarbon copolymer which uses an organic lithium compound as an initiator. A percentage of vinyl bonds in conjugated diene units in the copolymer molecules is from 50 to 95% and the content of the monovinyl aromatic hydrocarbon units is from 10 to 50% by weight. As physical properties of the vulcanized rubber of the rubber composition, aromatic hydrocarbon copolymer, 200% tensile modulus is from 5 to 50 kgf/cm.sup.2 and a temperture integrated value of a loss tangent, ##EQU1## is from 16 to 56. The tread rubber composition is suitable for a tread of high performance tires, and is excellent in fracture strength, thermal resistance, wear resistance, and road gripping property.
摘要翻译:公开了一种用于轮胎的橡胶组合物,其相对于整个橡胶组分含有至少30重量%的使用有机锂化合物作为引发剂的共轭二烯 - 单乙烯基芳族烃共聚物。 共聚物分子中共轭二烯单元中的乙烯基键的百分比为50〜95%,单乙烯基芳烃单元的含量为10〜50重量%。 作为橡胶组合物的硫化橡胶的物理性质,芳族烃共聚物的200%拉伸弹性模量为5〜50kgf / cm 2,损耗角正切值的温度积分值为16〜56。胎面橡胶 组合物适用于高性能轮胎的胎面,并且断裂强度,耐热性,耐磨性和道路抓地性优异。
摘要:
YA rubber composition for use in tire having improved rolling resistance, wet skid resistance and processability is disclosed, which comprises at least 20% by weight of a conjugated diolefin-vinyl-substituted aromatic hydrocarbon random copolymer. This random copolymer is produced by copolymerization with a particular initiator and coupling with a particular coupling agent, and has a content of vinyl-substituted aromatic hydrocarbon of 3-60% by weight, a content of tin bonded to copolymer of not less than 400 ppm and a Mooney viscosity (ML.sub.1+4.sup.100.degree.C.) of 20-200.
摘要:
A thermoplastic resin composition obtainable by blending 100 parts by weight of a mixture consisting of(A) 75 to 40% by weight of a propylene polymer,(B) 20 to 40% by weight of an ethylene-alpha-olefin copolymer, and(C) 5 to 30% by weight of a graft copolymer obtained by copolymerizing an aromatic vinyl compound and a polar vinyl compound in the presence of an ethylene-alpha-olefin copolymerwith(D) 0.1 to 5 parts by weight of an unsaturated dicarboxylic acid, an anhydride thereof or a mixture of the two, and(E) 0.01 to 0.3 part by weight of an organic radical-generating agent,and then subjecting the resulting blend to thermal treatment. Said composition has not only a high bending modulus inherently possessed by polypropylene resins but also remarkably improved coating property. Accordingly, the composition is useful as interior and exterior trim parts of automobiles and exterior trim parts of motorcycles.