Abstract: A chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, in which the chloroprene-unsaturated nitrile copolymer has a peak at 5.80 to 6.00 ppm in a 1H-NMR spectrum as measured in a deuterochloroform solvent, and a ratio (A/B) of a peak area (A) at 5.80 to 6.00 ppm and a peak area (B) at 4.05 to 6.20 ppm is 0.6/100 to 1.1/100.

Abstract: A chloroprene polymer having a structural unit derived from chloroprene and a structural unit derived from an unsaturated nitrile, in which the chloroprene polymer has peak tops at 5.80 to 6.00 ppm and 5.10 to 5.30 ppm in a 1H-NMR spectrum as measured in a deuterochloroform solvent, in the 1H-NMR spectrum, a peak area ratio A/B of a peak area A at 5.80 to 6.00 ppm and a peak area B at 4.05 to 6.20 ppm is 0.9/100 to 1.1/100, and the peak area A, the peak area B, and a peak area C at 5.10 to 5.30 ppm satisfy formula “(C?2A)/B?2.0/100”, and a content of the structural unit derived from an unsaturated nitrile is more than 0% by mass and 23% by mass or less.

Abstract: A chloroprene-unsaturated nitrile copolymer composition containing 100 parts by mass of a chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, and 0.05 to 2.0 parts by mass of a xanthogen compound.

Abstract: A composition comprises: a resin component including an olefin-aromatic vinyl compound-aromatic polyene copolymer satisfying all the following conditions (1) to (4): (1) a number average molecular weight of the copolymer is 500 or more and 100000 or less; (2) the aromatic vinyl compound monomer is an aromatic vinyl compound having 8 or more and 20 or less carbon atoms, and a content of a unit of the aromatic vinyl compound monomer is 0 mass % or more and 70 mass % or less; (3) the aromatic polyene is one or more selected from polyenes having 5 or more and 20 or less carbon atoms and having a plurality of vinyl groups and/or vinylene groups in the molecule, and a content of the vinyl groups and/or the vinylene groups derived from the unit of the aromatic polyene is 1.

Abstract: To provide a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit which has a satisfactory oil resistance. A method for producing a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit includes a step for conducting continuous addition or 10 cycles or more of intermittent portionwise addition of the chloroprene monomer after initiation of a polymerization reaction is provided. A rubber composition using a statistical copolymer according to the invention or a vulcanized molded article containing the rubber composition is excellent in terms of oil resistance, mechanical strength, compression set at a low temperature and flex fatigue resistance.

Abstract: A rubber composition containing: 100 parts by mass of a chloroprene-based rubber; 0.50 to 4.0 parts by mass of a maleimide compound; and 0.10 to 2.0 parts by mass of an organic peroxide, a vulcanizate of this rubber composition, and a vulcanized molded article of this rubber composition.

Abstract: Disclosed is a block copolymer including one or more blocks of an acrylate polymer and one or more blocks of a chloroprene polymer, wherein the number average molecular weight of the block copolymer is 110,000 or more, the number average molecular weight of the block of a chloroprene polymer is 80,000 or more in total, and the block copolymer has a functional group with a structure represented by the following chemical formula (1) or (2): wherein in the chemical formula (1), R1 represents hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group or a substituted, or unsubstituted heterocyclyl group.

Abstract: Provided is a chloroprene-based polymer having an industrially applicable sufficient molecular weight and capable of obtaining a vulcanized rubber excellent in durability and fatigue endurance and an adhesive excellent in layer separation resistance. A chloroprene-based polymer having a number average molecular weight Mn of 150000 to 300000 and comprising a functional group of a structure represented by the general formula (1) or (2) below: (wherein in the general formula (1), R1 shows hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclyl group.

Abstract: A chloroprene-unsaturated nitrile copolymer composition containing 100 parts by mass of a chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, and 0.05 to 2.0 parts by mass of a xanthogen compound.

Abstract: A chloroprene-unsaturated nitrile copolymer having 3 to 20% by mass of a structural unit derived from an unsaturated nitrile monomer, in which the chloroprene-unsaturated nitrile copolymer has a peak at 5.80 to 6.00 ppm in a 1H-NMR spectrum as measured in a deuterochloroform solvent, and a ratio (A/B) of a peak area (A) at 5.80 to 6.00 ppm and a peak area (B) at 4.05 to 6.20 ppm is 0.6/100 to 1.1/100.

Abstract: Disclosed is a block copolymer including one or more blocks of an acrylate polymer and one or more blocks of a chloroprene polymer, wherein the number average molecular weight of the block copolymer is 110,000 or more, the number average molecular weight of the block of a chloroprene polymer is 80,000 or more in total, and the block copolymer has a functional group with a structure represented by the following chemical formula (1) or (2): wherein in the chemical formula (1), R1 represents hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group or a substituted, or unsubstituted heterocyclyl group.

Abstract: To provide a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit which has a satisfactory oil resistance. A method for producing a statistical copolymer containing a chloroprene monomer unit and an unsaturated nitrile monomer unit includes a step for conducting continuous addition or 10 cycles or more of intermittent portionwise addition of the chloroprene monomer after initiation of a polymerization reaction is provided. A rubber composition using a statistical copolymer according to the invention or a vulcanized molded article containing the rubber composition is excellent in terms of oil resistance, mechanical strength, compression set at a low temperature and flex fatigue resistance.

Abstract: Provided is a chloroprene-based polymer having an industrially applicable sufficient molecular weight and capable of obtaining a vulcanized rubber excellent in durability and fatigue endurance and an adhesive excellent in layer separation resistance. A chloroprene-based polymer having a number average molecular weight Mn of 150000 to 300000 and comprising a functional group of a structure represented by the general formula (1) or (2) below: (wherein in the general formula (1), R1 shows hydrogen, chlorine, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclyl group.

Abstract: A cylinder head gasket for an internal combustion engine with a cylinder bore and a fluid hole includes a first metal plate having a curved portion around the cylinder bore and a folded portion extending from the curved portion, and a second metal plate laminated on the first metal plate and having a first full bead projecting toward the first metal plate. The first full bead is disposed on the folded portion. At least one secondary plate is inserted inside the folded portion.

Abstract: A cylinder head gasket for an internal combustion engine with a cylinder bore and a fluid hole includes a first metal plate having a curved portion around the cylinder bore and a folded portion extending from the curved portion, and a second metal plate laminated on the first metal plate and having a first full bead projecting toward the first metal plate. The first full bead is disposed on the folded portion. At least one secondary plate is inserted inside the folded portion.