An object of the present invention is to provide an aqueous coating composition that exhibits a small change in viscosity and can form a coating film having a superior coating film appearance even when the amount of a solvent contained in the aqueous coating composition decreases due to the change of the coating environment. The present invention provides an aqueous coating composition containing a polyurethane resin dispersion (A) and a melamine resin (B), wherein the melamine resin (B) contains a hydrophobic melamine resin, and the polyurethane resin constituting the polyurethane resin dispersion (A) has a viscosity in a range of 101 to 150,000 Pa.Math.s measured at a temperature of 25° C. and a shear rate of 0.1 sec.sup.−1.

A bacterial cellulose-polyurethane composite material, preparation method, and use are described. The preparation method comprises: performing organic solvent exchange on bacterial cellulose microfibers, and obtaining bacterial cellulose microfiber composite substance A and composite substance B of different concentrations; under oil bath conditions, adding a polymer polyol and a diisocyanate compound and performing an addition polymerization reaction, obtaining, via the reaction, a bacterial cellulose composite polyurethane foam prepolymer; and subsequently performing curing and obtaining the bacterial cellulose-polyurethane composite material. By combining bacterial cellulose microfibers and polyurethane foam material, the mechanical properties of the composite material are significantly improved; the large amount of hydroxyl groups on the surfaces of the bacterial cellulose nanofibers effectively strengthens the hydrophilicity and water absorption capability of the composite material; and the favorable tissue affinity of bacterial cellulose can also improve the biocompatibility of polyurethane material.

Disclosed are compositions that may be useful for forming synthetic membranes, methods of forming membranes therefrom, and membranes. In an embodiment, a membrane comprises a free hydrophilic polymer comprising a polyoxazoline, and a polyurethane, the polyurethane comprising a backbone comprising the reaction product of a diisocyanate, a polymeric aliphatic 5 diol, and optionally a chain extender.

The present invention relates to a thermoplastic silicone-polyurethane elastomer and a method for preparing the same. The elastomer is prepared from raw materials comprising: 25-80 parts of a macromolecular polyol, 0-60 parts of a silicone oil or a liquid silicone rubber, 10-50 parts of a diisocyanate, 3-20 parts of a small molecular diol as a chain extender, and 0.1-3 parts of an auxiliary agent. The macromolecular polyol is selected from a silicon-free polyol having a molecular weight of between 1,000 and 4,000 g/mol and a polyol modified by silicone through copolymerization or grafting. The small molecular diol is a small molecular diol comprising 10 or less carbon atoms. The thermoplastic silicone-polyurethane elastomer of the present invention has the following excellent performance parameters: a hardness of Shore A40-D80; a tensile strength ≥5 MPa; smooth hand feeling; resistance to dirt such as dust; resistance to liquid permeation; no irritation to skin; good encapsulation effect on PC, ABS, TPU and the like; and a 180° peel strength >25 N/25 mm.

The present application relates to aziridine functional compounds with reduced genotoxicity and good crosslinking efficiency, for use in the preparation of, for example, coatings.

##STR00001##

The present invention relates to ultralow monomer PU prepolymers containing free NCO groups obtainable from polyols, diisocyanates and NCO-reactive compounds, obtainable by reacting at least one polyol with at least one polyisocyanate, wherein the at least one polyisocyanate is used in molar excess relative to the hydroxyl groups of the at least one polyol to obtain a polyurethane prepolymer containing free isocyanate groups; and adding at least one compound having at least one H-acidic functional group to the polyurethane prepolymer containing free isocyanate groups in an amount such that the molar ratio of the free isocyanate groups to H-acidic functional groups (NCO:XH ratio) is 2 to 15, preferably 2.5 to 10, more preferably 3 to 8. Also encompassed are methods for its production, laminating adhesives containing said prepolymer, methods of bonding substrates and the use of the described adhesives for laminating two or more films.

The present invention relates to a multi-aziridine crosslinker composition, characterized in that the multi-aziridine crosslinker composition is an aqueous dispersion having a pH ranging from 8 to 14 and comprises a multi-aziridine compound in dispersed form, wherein said multi-aziridine compound has: a. from 2 to 6 of the following structural units A: whereby R.sub.1 is H, R.sub.2 and R.sub.4 are independently chosen from H or an aliphatic hydrocarbon group containing from 1 to 4 carbon atoms, R a is an aliphatic hydrocarbon group containing from 1 to 4 carbon atoms, m is 1, b. one or more linking chains wherein each one of these linking chains links two of the structural units A; and c. a molecular weight in the range from 500 to 10000 Daltons wherein the molecular weight is determined using MALDI-TOF mass spectrometry according to the description.

##STR00001##

There is provided a two-part urethane adhesive composition including: a main agent containing a polyisocyanate component (A); and a curing agent containing water and an active hydrogen-containing compound (B). The (B) contains a compound represented by Formula (4); the (A) contains a urethane prepolymer (A-3); an average active hydrogen concentration of the (B) is 0.50 to 3.50 mol/kg; an average active hydrogen concentration of the (B) and the water is 2.00 to 8.00 mol/kg. The main agent and the curing agent are mixed in such amounts as to satisfy conditions that: a ratio of the number of isocyanate groups of the (A) to the number of active hydrogens of the (B) is 1 to 5; and a ratio of the number of isocyanate groups of the (A) to the total number of active hydrogens of the (B) and the water is 0.5 to 2.5.

A self-repairing polyurethane resin material is produced by reaction of a polyisocyanate compound consisting of aliphatic polyisocyanate and/or araliphatic polyisocyanate with an active hydrogen group-containing compound, used for producing polyurethane resin having self-repairing properties, has an isocyanate group at its molecular terminal, contains an allophanate group and an isocyanate trimer, and the mole ratio of the allophanate group relative to the isocyanate trimer is 0.1 to 20.

An object of the present invention is to provide a golf ball having excellent abrasion resistance and spin performance on driver shots. The present invention provides a golf ball having a spherical core and a cover covering the spherical core, wherein the cover contains a polyurethane, wherein the polyurethane comprises, as a constituent component, (A) a polyisocyanate component and (B) a polyol component containing (b1) a polyrotaxane, and wherein (b1) the polyrotaxane has a cyclodextrin, a linear molecule piercing through the cyclic structure of the cyclodextrin, and a blocking group located at both terminals of the linear molecule to prevent disassociation of the cyclodextrin, and at least a part of hydroxyl groups of the cyclodextrin is modified with a caprolactone chain via —O—C.sub.3H.sub.6—O— group.