Polyurethanes are made by reacting, in one or more reaction steps, a) at least one organic polyisocyanate, b-1) one or more polyols having a hydroxyl equivalent weight of greater than 250 g/mol and a nominal hydroxyl functionality of 2 to 4 and b-2) at least one alkoxylated Mannich base to produce a polyurethane polymer having a density of at least 750 kg/m3 and a hard segment content of 20 to 80% by weight.

Polyol premixes and thermally insulating rigid polyurethane foams, such as those that can be used as a thermal insulation medium in the construction of refrigerated storage devices, are disclosed. A polymer polyol having a OH number of greater than 260 mg KOH/g is utilized. The resulting polyurethane foams can exhibit improved thermal insulation properties without sacrificing other important physical and processing properties.

Provided are a carbodiimide-based, waterborne resin crosslinking agent that not only is excellent in the storage stability when the crosslinking agent and a waterborne resin are caused to coexist, but also can improve physical properties such as solvent resistance and water resistance of a cured product of the waterborne resin, and a waterborne resin crosslinking agent-containing liquid and a waterborne resin composition comprising the same. The waterborne resin crosslinking agent of the present invention comprises a predetermined polycarbodiimide compound (A) having an oxyalkylene group, a predetermined polycarbodiimide compound (B), and a surfactant (C), each polycarbodiimide compound has a structure in which an isocyanate group is capped with a predetermined end-capping compound at each of both terminals, a total content of the oxyalkylene group in (A) is 15% by mass or more, a total content of the oxyalkylene group in (A) and (B) based on a total amount of (A) and (B) is 10% by mass or less, and a content of (C) is 0.1 to 20 parts by mass based on a total content of (A) and (B) of 100 parts by mass.

A polymer having a repeating unit represented by Formula 1:

##STR00001## wherein each of R.sub.1, R.sub.2, and R.sub.3 is independently selected from a substituted or unsubstituted C1-C6 chain-like saturated or unsaturated hydrocarbon group having 0 to 2 first heteroatoms or a substituted or unsubstituted C3-C6 cyclic saturated or unsaturated hydrocarbon group having 0 to 2 first heteroatoms, wherein at least one of R.sub.1, R.sub.2, and R.sub.3 is a hydrocarbon group substituted with a fluorine atom. R.sub.4 is a C1-C10 chain-like saturated or unsaturated hydrocarbon group having 0 to 2 second heteroatoms or a C3-C10 cyclic saturated or unsaturated hydrocarbon group having 0 to 2 second heteroatoms. R.sub.5 is a C1-C10 chain-like saturated or unsaturated hydrocarbon group having 1 to 6 third heteroatoms or a C3-C10 cyclic saturated or unsaturated hydrocarbon group having 1 to 6 third heteroatoms.

An alternative polyurethane composition is provided comprising a reaction product of an azidated polyol and a poly(alkynyl carbamate) allophanate prepolymer, wherein the poly(alkynyl carbamate) allophanate prepolymer comprises a reaction product of a first alkynol and a poly(alkynyl carbamate) prepolymer, in the presence of a metallo-organic compound of the formula: M(acac).sub.n, wherein, M=a metal, acac=an acetylacetonate residue, and n=2 or 3, wherein the poly(alkynyl carbamate) prepolymer comprises a reaction product of a polyisocyanate and a stoichiometric equivalent of a second alkynol, and wherein the polyisocyanate comprises isocyanate groups and uretdione groups. The inventive alternative polyurethane compositions may be used to provide solventborne or waterborne coatings, adhesives, sealants, films, elastomers, castings, foams, and composites.

A Schiff base-containing chain extender may be a diol having a Schiff base or a derivative thereof, as well as a polyurethane produced using the same and a modification method thereof, and a polishing layer including a polyurethane and a polishing method using the polishing layer.

The present invention relates to a composition comprising a first component containing at least one polyol, and a second component containing at least one polyisocyanate, the composition further comprising at least one aldimine of formula (I). The composition exhibits a long open time and fast curing without odor immissions, wherein a bubble-free, elastic material having a non-tacky surface and good strength, extensibility, elasticity and resistance is produced, which does not tend to problems arising with plasticizer migration.

A method for functionalizing the surface of a substrate, performed in a supercritical fluid medium, may include: (i) providing a substrate having labile hydrogen functions on the surface; (ii) bringing the substrate into contact, in a supercritical fluid, with at least one organic molecule carrying at least one blocked isocyanate function which can be activated by heating; and (iii) subjecting the whole to a temperature sufficient to bring about the release of the blocked isocyanate function carried by the molecule, and the covalent grafting of the molecule by reaction of the isocyanate function with a labile hydrogen function on the surface of the substrate.

Polyol premixes and thermally insulating rigid polyurethane foams, such as those that can be used as a thermal insulation medium in the construction of refrigerated storage devices, are disclosed. A polymer polyol having a OH number of greater than 260 mg KOH/g is utilized. The resulting polyurethane foams can exhibit improved thermal insulation properties without sacrificing other important physical and processing properties.

A polymerizable composition for an optical material includes a prepolymer which is a reaction product of a first amine compound (A1) having a weight-average molecular weight of less than 4,000, a first diol compound (B1) having a viscosity (25° C.) of equal to or less than 100 mPa.Math.s, and a polyisocyanate compound (C); and a first polythiol compound (D1), in which the first amine compound (A1) is at least one selected from a polyetheramine and an aromatic amine, and the first polythiol compound (D1) includes a dithiol compound (d1) having two mercapto groups and a polythiol compound (d2) having equal to or more than three mercapto groups.