A method for preparing a high-temperature self-crosslinking aqueous polyurethane dispersion. By using isocyanate (NCO) blocking agent to block part of the NCO, and using the hydroxyalkyl ethylenediamine chain extender in the post-chain extension stage to introduce hydroxyl groups, the polymer macromolecular structure containing both blocked NCO groups and hydroxyl groups can be prepared. The aqueous polyurethane dispersion does not need to mix with other waterborne resins and crosslinkers when applied. A sufficient cross-linking reaction is performed between the NCO released and hydroxyl groups on the polymer macromolecular chain to form a high-density cross-linked structure when curing at 100-150° C. for 20-30 min, thus obtaining a high-performance waterborne coating that can be used in the form of one-pack.

An organosilicon-modified polyurethane resin and a method for producing the same are provided. The organosilicon-modified polyurethane resin includes organosilicon ingredients obtained by chemically bonding a first organosilicon chain extender having a chemical structure of formula (I) and a second organosilicon chain extender having a chemical structure of formula (II) into a molecular structure of a polyurethane resin during a polymerization reaction:

##STR00001##

in which R.sub.11 is a substituent of —CH.sub.2CH.sub.2— or —CH.sub.2CH(CH.sub.3)—, n.sub.1 is a positive integer between 0 and 50, m.sub.1 is a positive integer between 0 and 50, and x.sub.1 is a positive integer between 4 and 100;

##STR00002##

in which R.sub.21 is a substituent of —CH.sub.3 or —CH.sub.2CH.sub.3, R.sub.22 is a substituent of —CH.sub.2CH.sub.2CH.sub.2—, and R.sub.23 is a substituent of —CH.sub.2CH.sub.2— or —CH.sub.2CH(CH.sub.3)—, n.sub.2 is a positive integer between 6 and 130, and m.sub.2 is a positive integer between 4 and 50.

Acid-catalyzed curable coating compositions containing 1,1-di-activated vinyl compounds are described, including multi-layer coatings. Also provided are processes for coating substrates with coating compositions comprising 1,1-di-activated vinyl N compounds. Also provided are coated articles comprising coatings formed from coating compositions comprising 1,1-di-activated vinyl compounds.

Polyurethanes containing at least one bisphosphonate group, as well as related compositions, articles, and methods, are disclosed.

To provide a binder that has high adhesiveness to a collector, does not cause release in press molding, has high flexibility, and is excellent in binding capability and resistance to an electrolytic solution, and to provide a lithium secondary battery that is excellent in charge and discharge characteristics using an electrode produced with the binder. The binder for an electrode used contains a hydrophilic group-containing polyurethane as a water dispersion that contains (A) a polyisocyanate, (B) a compound that has two or more active hydrogen groups, (C) a compound that has one or more active hydrogen groups and one or more hydrophilic groups, and (D) a chain extending agent, or contains an aqueous resin composition containing a polymer of an unsaturated polymerizable monomer that is emulsified with the hydrophilic group-containing polyurethane.

The present invention relates to an extruded expanded thermoplastic polyurethane elastomer bead and a preparation method therefor. The bead consists of components of the following parts by weight: 100 parts by weight of a thermoplastic polyurethane elastomer, 0.01-0.5 parts of a foaming nucleating agent, and 0.01-0.2 parts by weight of an antioxidant. The preparation method comprises: mixing materials, then putting the mixture into an extruder for granulation to produce a particle raw material suitable for foaming, finally, putting the particle into a foam extruder, and die foaming then underwater pelletizing, thus obtaining a product bead. The present invention utilizes an extrusion method to prepare expanded thermoplastic polyurethane beads. Control of the working conditions of the foaming process could lead to acquiring an expanded=bead of a controllable density, the cell density evenly distribute. The overall production process is easy to operate. Without any special limit or requirement placed on the equipment, this method is suitable for industrial continuous production.

There is provided an adhesive composition comprising at least 50 wt % of an aqueous dispersion of an amorphous polyurethane having a Tg below 25° C.; and a water dispersible cross-linker, where the adhesive composition has a peel retention of greater than or equal to 5% according to the Water/IPA Exposure Test.

A process for producing a rigid polymer foam comprises reacting components A to C in the presence of component D or an isocyanate-functional prepolymer of components A and B with component C in the presence of component D, the total amount of which is 100 wt %, (A) 35 to 65 wt % of at least one polyisocyanate component A, (B) 5 to 50 wt % of at least one polyol component B, (C) 1 to 59 wt % of at least one polycarboxylic acid component C, and (D) 0.01 to 3 wt % of at least one Lewis base component D,
wherein the reaction takes place with release of carbon dioxide.

A polymer containing silane groups, a method for synthesizing same, and curable compositions including the polymer. The polymer containing silane groups has a very long shelf life and cures quickly with moisture. The polymer is suitable as an elastic adhesive or sealant or coating that can be applied at room temperature and has good heat resistance, or as a hot melt adhesive.

Disclosed herein is a polyurethane foam sponge produced by the steps of a) providing an hydrophobic polyol which has six hydroxyl groups, b) providing a hydrophilic diisocyanate obtained by reacting a diisocyanate with a hydrophilic polyether diol, c) reacting the hydrophobic polyol with the hydrophilic diisocyanate to obtain a prepolymer which includes 3 to 6 isocyanate groups, and d) mixing the prepolymer with a hydrophilic polyether polyol, a blowing agent, an end-capping agent, a reinforcing agent, and a catalyst to obtain the polyurethane foam sponge. A wound dressing including the polyurethane foam sponge is also disclosed.