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.

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.

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.

The invention relates to a polyacrylate-based graft copolymer comprising a polyacrylate backbone and polyolefin side chains grafted thereon, wherein the graft copolymer is prepared by reacting a first polymer and a second polymer, wherein the first polymer comprises recurring units having the structure (I) and optionally further recurring units having the structures (II): Formulae (I), (II) wherein R.sup.1, R.sup.3 is H or CH.sub.3 and R.sup.2 is a hydrocarbon moiety comprising 1 to 6 carbon atoms, one of R.sup.4 and R.sup.5 is H and the other one of R.sup.5 and R.sup.4 is COOR.sup.2, C═N, Cl, or an aliphatic or aromatic hydrocarbon moiety optionally containing one or multiple hetero atom functionalities, wherein R.sup.2 in (I) is different from R.sup.2 in (II) and the second polymer is a functionalized polyolefin having one or multiple hydroxyl functional groups, wherein the graft copolymer is formed by transesterification of the COOR.sup.2 group of (1) or (II) with the hydroxyl functional group of the functionalized polyolefin.

The invention relates to a polyacrylate-based graft copolymer comprising a polyacrylate backbone and polyolefin side chains grafted thereon, wherein the graft copolymer is prepared by reacting a first polymer and a second polymer, wherein the first polymer comprises recurring units having the structure (I) and optionally further recurring units having the structures (II): Formulae (I), (II) wherein R.sup.1, R.sup.3 is H or CH.sub.3 and R.sup.2 is a hydrocarbon moiety comprising 1 to 6 carbon atoms, one of R.sup.4 and R.sup.5 is H and the other one of R.sup.5 and R.sup.4 is COOR.sup.2, C═N, Cl, or an aliphatic or aromatic hydrocarbon moiety optionally containing one or multiple hetero atom functionalities, wherein R.sup.2 in (I) is different from R.sup.2 in (II) and the second polymer is a functionalized polyolefin having one or multiple hydroxyl functional groups, wherein the graft copolymer is formed by transesterification of the COOR.sup.2 group of (1) or (II) with the hydroxyl functional group of the functionalized polyolefin.

The invention discloses an iron bipyridine complex, a preparation method of the same, and use of the same in polymerization of conjugated dienes the invention provides an iron bipyridine complex, which is used as a primary catalyst showing high activity in the polymerization of polyprene to obtain a polymer with a high branched-chain degree. The polymer has the characteristics of a high molecular weight and narrow molecular weight distribution, and the molecular weight of the polymer can be adjusted by a chain transfer reagent. The obtained poly(conjugated diene) rubber has high branched-chain content and an ultrahigh molecular weight. Because there are a large number of side groups on the molecular chains of the rubber, the rubber is mainly used for preparing high-performance tires and other related rubber products with good wet traction and low friction-induced heat generation.

The invention discloses an iron bipyridine complex, a preparation method of the same, and use of the same in polymerization of conjugated dienes the invention provides an iron bipyridine complex, which is used as a primary catalyst showing high activity in the polymerization of polyprene to obtain a polymer with a high branched-chain degree. The polymer has the characteristics of a high molecular weight and narrow molecular weight distribution, and the molecular weight of the polymer can be adjusted by a chain transfer reagent. The obtained poly(conjugated diene) rubber has high branched-chain content and an ultrahigh molecular weight. Because there are a large number of side groups on the molecular chains of the rubber, the rubber is mainly used for preparing high-performance tires and other related rubber products with good wet traction and low friction-induced heat generation.

Some embodiments of the disclosure provides polyacrylonitrile (PAN) and a preparation method and use thereof. The method includes the following steps. Mixing raw materials for polymerization to obtain a suspension comprising the PAN. The raw materials include an acrylonitrile monomer, a first auxiliary monomer, a second auxiliary monomer, a polymerization medium, an initiator, a chain transfer agent, and a settling agent. Removing unreacted monomers and unreacted polymerization medium in the suspension to obtain the PAN. After subsequent removal of monomers, removal of a polymerization medium, washing, and drying, a PAN powder is obtained. In some embodiments, the preparation method of the PAN has a wide adjustable range of a PAN copolymerization composition, a low viscosity of a polymerization system, a high concentration of a polymerized monomer, and a strong anti-scaling ability.

Provided are an apparatus and a method for manufacturing high-pressure method low-density polyethylene, the apparatus and the method having excellent characteristics that a chain transfer agent can be supplied by a simpler apparatus, a deviation (variation) of the concentration of the chain transfer agent supplied to a reactor can be reduced, and compression energy of the chain transfer agent can be reduced. An apparatus for manufacturing high-pressure method polyethylene includes a chain transfer agent supply line that is a line connected to a low pressure recycle ethylene supply line for supplying a chain transfer agent.

Provided are an apparatus and a method for manufacturing high-pressure method low-density polyethylene, the apparatus and the method having excellent characteristics that a chain transfer agent can be supplied by a simpler apparatus, a deviation (variation) of the concentration of the chain transfer agent supplied to a reactor can be reduced, and compression energy of the chain transfer agent can be reduced. An apparatus for manufacturing high-pressure method polyethylene includes a chain transfer agent supply line that is a line connected to a low pressure recycle ethylene supply line for supplying a chain transfer agent.