The present invention provides a molded bale of a rubber composition that is difficult to cold flow, and is difficult to be thermally deteriorated during production, and in which rigidity at 50° C. of a rubber composition for crosslinking obtained therefrom is difficult to be low, and change of tensile strength of the rubber composition for crosslinking after thermal history is small. The rubber composition contains: a rubber-like polymer (A) having an iodine value of 10 to 250, 3% by mass or more of an ethylene structure, and less than 10% by mass of a vinyl aromatic monomer block; aluminum (B); and nickel and/or cobalt (C), in which a content of the aluminum (B) is 2 ppm or more and 200 ppm or less, and a content of the nickel and/or cobalt (C) is 3 ppm or more and 100 ppm or less.

A catalyst composition for selectively hydrogenating a conjugated diene polymer in a homogeneous system is provided, wherein the conjugated diene polymer comprises a conjugated diene monomer or a combination of a conjugated diene monomer and a vinyl aromatic monomer. The catalyst composition includes the catalyst components of (a) a titanium compound; (b) an organometallic compound; and (c) an oligomer containing a polyglycol segment. The hydrogenated polymer produced using the catalyst composition and the method thereof is also provided.

A catalyst composition for selectively hydrogenating a conjugated diene polymer in a homogeneous system is provided, wherein the conjugated diene polymer comprises a conjugated diene monomer or a combination of a conjugated diene monomer and a vinyl aromatic monomer. The catalyst composition includes the catalyst components of (a) a titanium compound; (b) an organometallic compound; and (c) an oligomer containing a polyglycol segment. The hydrogenated polymer produced using the catalyst composition and the method thereof is also provided.

The present invention relates to the use of Ru and Os carbene complexes with a hydroxamic acid (ester) function for the metathesis degradation of nitrile rubber (NBR). The invention further relates to a method for producing hydrogenated nitrile rubbers, by subjecting a nitrile rubber to a metathesis degradation in the presence of the said catalyst, and the degraded nitrile rubber obtained subsequently undergoes a hydrogenation, preferably in situ.

The present invention relates to the use of Ru and Os carbene complexes with a hydroxamic acid (ester) function for the metathesis degradation of nitrile rubber (NBR). The invention further relates to a method for producing hydrogenated nitrile rubbers, by subjecting a nitrile rubber to a metathesis degradation in the presence of the said catalyst, and the degraded nitrile rubber obtained subsequently undergoes a hydrogenation, preferably in situ.

The invention relates to polymeric-inorganic nanoparticle compositions and preparation processes thereof. The invention also relates to an additive and lubricant compositions comprising these polymeric-inorganic nanoparticle compositions, as well as to the use of these polymeric-inorganic nanoparticle compositions in an oil lubricant formulation to improve tribological performance, in particular to improve extreme pressure performance and friction reduction on metal parts.

The present invention provides a 1,3,7-octatriene polymer having a narrow molecular weight distribution and a hydride thereof. Specifically, the 1,3,7-octatriene polymer is a polymer containing a structural unit derived from 1,3,7-octatriene, wherein the polymer has not only a molecular weight distribution (Mw/Mn) of 2.05 or less but also a weight average molecular weight (Mw) of 1,000 to 1,000,000.

A method for producing a carboxy group-containing hydrogenated nitrile rubber includes a step of preparing a latex of a carboxy group-containing nitrile rubber by polymerizing a monomer mixture in a dispersive medium, the monomer mixture containing at least an α,β-ethylenically unsaturated nitrile monomer and a carboxy group-containing monomer; a step of heating the latex of the carboxy group-containing nitrile rubber at 50 to 85° C. in the state where the pH is adjusted in the range of 8.5 to 12; and a step of subjecting the latex of the carboxy group-containing nitrile rubber after the heating to a hydrogenation reaction in the presence of a hydrogenation catalyst in the state where the pH is adjusted in the range of 5 to 8.

A method for producing a carboxy group-containing hydrogenated nitrile rubber includes a step of preparing a latex of a carboxy group-containing nitrile rubber by polymerizing a monomer mixture in a dispersive medium, the monomer mixture containing at least an α,β-ethylenically unsaturated nitrile monomer and a carboxy group-containing monomer; a step of heating the latex of the carboxy group-containing nitrile rubber at 50 to 85° C. in the state where the pH is adjusted in the range of 8.5 to 12; and a step of subjecting the latex of the carboxy group-containing nitrile rubber after the heating to a hydrogenation reaction in the presence of a hydrogenation catalyst in the state where the pH is adjusted in the range of 5 to 8.

A latex of a highly saturated nitrile rubber wherein the highly saturated nitrile rubber contains α,β-ethylenically unsaturated nitrile monomer units in a ratio of 10 to 60 wt %, has an iodine value of 120 or less, and has a weight average molecular weight of solubles in chloroform of 100,000 or less, and when removing volatiles contained in the latex and making a film of the highly saturated nitrile rubber, a loss tangent tan δ.sub.(50° C.) at 50° C. of the film is 0.3 to 0.6 and a complex torque S* at the time of 100% shear strain at 100° C. of the film is 20 dNm or less, and an adhesive composition containing the latex are provided.