The present invention relates to a polyisocyanate composition comprising, on the basis of the total mass of the polyisocyanate composition, 97 weight % or more of a polyisocyanate, and 2.0 mass ppm or more and 1.0×10.sup.4 mass ppm or less of a compound having at least one unsaturated bond in which the compound is a different compound from the polyisocyanate, or 5.0 mass ppm or more and 2.0×10.sup.4 mass ppm or less of at least one inactive compound selected from the group consisting of a hydrocarbon compound, an ether compound, a sulfide compound, a halogenated hydrocarbon compound, a Si-containing hydrocarbon compound, a Si-containing ether compound, and a Si-containing sulfide compound.

A process for continuous preparation of oligomeric or polymeric isocyanates by catalytic modification of monomeric di- and/or triisocyanates, characterized in that at least one isocyanate component A and at least one catalyst component B are combined continuously in a reaction apparatus and conducted through the reaction apparatus as a reaction mixture, the residence time distribution being characterized according to the dispersion model by Bo (Bodenstein number) above 40, preferably above 60 and most preferably above 80.

A surface-treating agent for vulcanized rubber, comprising 10 to 160 parts by weight of a wax having a softening point of 40 to 160° C. and 10 to 160 parts by weight of fluororesin particles based on 100 parts by weight of the total amount of isocyanate group-containing 1,2-polybutadiene and an OH group-containing fluororesin composition that has the following formulation:

a copolymer [I] of (A) a perfluoroalkylalkyl (meth)acrylate and (B) a hydroxyl group-containing (meth)acrylate,

a polymer [II] of an acrylic acid alkyl ester,

a polymer [III] of a fluorinated olefin, and

a curing agent [IV];

wherein the weight ratio of the isocyanate group-containing 1,2-polybutadiene and the OH group-containing fluororesin composition is 50:50 to 95:5.

A surface-treating agent for vulcanized rubber, comprising 10 to 160 parts by weight of a wax having a softening point of 40 to 160° C. and 10 to 160 parts by weight of fluororesin particles based on 100 parts by weight of the total amount of isocyanate group-containing 1,2-polybutadiene and an OH group-containing fluororesin composition that has the following formulation:

a copolymer [I] of (A) a perfluoroalkylalkyl (meth)acrylate and (B) a hydroxyl group-containing (meth)acrylate,

a polymer [II] of an acrylic acid alkyl ester,

a polymer [III] of a fluorinated olefin, and

a curing agent [IV];

wherein the weight ratio of the isocyanate group-containing 1,2-polybutadiene and the OH group-containing fluororesin composition is 50:50 to 95:5.

The instant invention provides an isocyanate trimerisation catalyst system, a precursor formulation, a process for trimerising isocyanates, rigid foams made therefrom, and a process for making such foams. The trimerisation catalyst system comprises: (a) a phosphatrane cation; and (b) an isocyanate-trimer inducing anion; wherein said trimerisation catalyst system has a trimerisation activation temperature in the range of equal to or less than 73° C. The precursor formulation comprises (1) at least 25 percent by weight of polyol, based on the weight of the precursor formulation; (2) less than 15 percent by weight of a trimerisation catalyst system, based on the weight of the precursor formulation, comprising; (a) a phosphatrane cation; and (c) an isocyanate-trimer inducing anion; wherein said trimerisation catalyst system has a trimerisation activation temperature in the range of equal to or less than 73° C.; and (4) optionally one or more surfactants, one or more flame retardants, water, one or more antioxidants, one or more auxiliary blowing agents, one or more urethane catalysts, one or more auxiliary trimerisation catalysts, or combinations thereof. The process for trimerisation of isocyanates comprises the steps of: (1) providing one or more monomers selected from the group consisting of an isocyanate, a diisocyanate, a triisocyanate, oligomeric isocyanate, a salt of any thereof, and a mixture of any thereof; (2) providing a trimerisation catalyst system comprising; (a) an phosphatrane cation; and (b) an isocyanate-trimer inducing anion; (c) wherein said trimerisation catalyst system has a trimerisation activation temperature in the range of equal to or less than 73° C.; (3) trimerising said one or more monomers in the presence of said trimerisation catalyst; (4) thereby forming an isocyanurate ring. The process for making the PIR foam comprises the steps of: (1) providing one or more monomers selected from the group consisting of an isocyanate, a diisocyanate, a triisocyanate, oligomeric isocyanate, a salt of any thereof, and a mixture of any thereof; (2) providing polyol; (3) providing a trimerisation catalyst system comprising; (a) a phosphatrane cation; and (b) an isocyanate-trimer inducing anion; wherein said trimerisation catalyst system has a trimerisation activation temperature in the range of equal to or less than 73° C.; and (4) optionally providing one or more surfactants, one or more flame retardants, water, one or more antioxidants, one or more auxiliary blowing agents, one or more urethane catalysts, one or more auxiliary trimerisation catalysts, or combinations thereof; (5) contacting said one or more monomers, and said polyol, and op

This invention relates to a method of preparing a microcellular polyurethane elastomer by reacting naphthalene diisocyanate with a polyol to prepare a prepolymer containing an isocyanate (NCO) group, followed by mixing the prepared polyurethane prepolymer with a plasticizer, water, an emulsifier and the like, and then foaming the prepolymer blend to prepare a polyurethane elastomer, wherein the emulsifier is a mixture of (a) a compound selected from the group consisting of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, 1,4′-cyclohexane diisocyanate and mixtures thereof, and (b) a C.sub.2-10 hydrocarbon having a molecular weight of 500 or less with two to four hydroxyl groups, or mixtures thereof. The method of the invention can optimize the viscosity and properties of the prepolymer resulting from the reaction of naphthalene diisocyanate with a polyol, thus improving processability.

This invention relates to a method of preparing a microcellular polyurethane elastomer by reacting naphthalene diisocyanate with a polyol to prepare a prepolymer containing an isocyanate (NCO) group, followed by mixing the prepared polyurethane prepolymer with a plasticizer, water, an emulsifier and the like, and then foaming the prepolymer blend to prepare a polyurethane elastomer, wherein the emulsifier is a mixture of (a) a compound selected from the group consisting of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, 1,4′-cyclohexane diisocyanate and mixtures thereof, and (b) a C.sub.2-10 hydrocarbon having a molecular weight of 500 or less with two to four hydroxyl groups, or mixtures thereof. The method of the invention can optimize the viscosity and properties of the prepolymer resulting from the reaction of naphthalene diisocyanate with a polyol, thus improving processability.

Polyurea crosslinked particles for a transport device member are provided that have high acid resistance, increase long-term retainability when included in a coating film, and are capable of maintaining a high sliding property for a long time. The polyurea crosslinked particles for a transport device member are particles formed of reactants of a self-emulsifying isocyanate having two or more isocyanate groups and a non-self-emulsifying isocyanate having two or more isocyanate groups and having a ring structure in the presence of water and a crosslink density thereof is 1×10.sup.−4 mol/g or more.

Polyurea crosslinked particles for a transport device member are provided that have high acid resistance, increase long-term retainability when included in a coating film, and are capable of maintaining a high sliding property for a long time. The polyurea crosslinked particles for a transport device member are particles formed of reactants of a self-emulsifying isocyanate having two or more isocyanate groups and a non-self-emulsifying isocyanate having two or more isocyanate groups and having a ring structure in the presence of water and a crosslink density thereof is 1×10.sup.−4 mol/g or more.

The invention relates to a method for producing polyisocyanates having a low monomer content, said method comprising the following steps: (i) modifying at least one monomeric diisocyanate to obtain a mixture containing at least one polyisocyanate and unconverted monomeric diisocyanate, (ii) separating the mixture obtained in step (i) into at least one gaseous stream containing monomeric diisocyanate and a liquid stream depleted of monomeric diisocyanate, (iii) partially condensing the gaseous stream from (ii) in at least one condenser, so that a liquid condensate and an uncondensed vapour stream are obtained, (iv) post-condensing the uncondensed vapour stream obtained in step (iii) in at least one post-condenser, so that a post-condensate and an uncondensed waste gas are obtained, and (v) delivering the uncondensed waste gas from step (iv) to the suction side of a vacuum pump, characterised in that the at least one post-condenser in step (iv) is operated at a post-condenser temperature, and the at least one condenser in step (iii) is operated at a condenser temperature, wherein the post-condenser temperature is lower by ≥1 to ≤168 K than the condenser temperature.