Provided is a cycloolefin resin cured product having oxygen barrier properties prepared through bulk polymerization of a polymerizable composition comprising a cycloolefin monomer and a metathesis polymerization catalyst, wherein the cycloolefin monomer includes a norbornene-based monomer (a), the polymerizable composition comprises an antioxidant in an amount of 0.3% by mass or less, and the cycloolefin resin cured product has an oxygen permeability at 23 C. of less than 50 mL/m.sup.2.Math.day.Math.atm (100 m).

Provided is a cycloolefin resin cured product having oxygen barrier properties prepared through bulk polymerization of a polymerizable composition comprising a cycloolefin monomer and a metathesis polymerization catalyst, wherein the cycloolefin monomer includes a norbornene-based monomer (a), the polymerizable composition comprises an antioxidant in an amount of 0.3% by mass or less, and the cycloolefin resin cured product has an oxygen permeability at 23 C. of less than 50 mL/m.sup.2.Math.day.Math.atm (100 m).

Provided is a sulfur-containing unsaturated hydrocarbon polymer which can improve wet grip performance and fuel efficiency of a tire in a well-balanced manner by being blended into a rubber composition for a tire. A sulfur-containing unsaturated hydrocarbon polymer of the present invention is a reaction product obtained by reacting sulfur with an unsaturated bond in a polymer of an unsaturated hydrocarbon.

Provided is a sulfur-containing unsaturated hydrocarbon polymer which can improve wet grip performance and fuel efficiency of a tire in a well-balanced manner by being blended into a rubber composition for a tire. A sulfur-containing unsaturated hydrocarbon polymer of the present invention is a reaction product obtained by reacting sulfur with an unsaturated bond in a polymer of an unsaturated hydrocarbon.

Provided is a catalyst solution comprising a metathesis polymerization catalyst, a coordinating compound containing a phosphorus atom, and a solvent, wherein the metathesis polymerization catalyst is a ruthenium-carbene complex represented by General Formula (1) or (2) below, and the coordinating compound containing a phosphorus atom is contained in an amount such that 6 to 1000 mol of phosphorus atoms are contained relative to 1 mol of ruthenium atoms in the metathesis polymerization catalyst.

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Provided is a catalyst solution comprising a metathesis polymerization catalyst, a coordinating compound containing a phosphorus atom, and a solvent, wherein the metathesis polymerization catalyst is a ruthenium-carbene complex represented by General Formula (1) or (2) below, and the coordinating compound containing a phosphorus atom is contained in an amount such that 6 to 1000 mol of phosphorus atoms are contained relative to 1 mol of ruthenium atoms in the metathesis polymerization catalyst.

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