摘要:
A process for the preparation of sulfonated polyurethane-urea polymers, which are useful film to film laminating adhesives for flexible packaging in which the urethane-urea polymer component has no amide linkages. The water-based sulfonated polyurethane prepolymers are processed at reduced temperatures and are substantially free of volatile and/or leachable contaminants.
摘要:
Methodology for constructing composite particles from ingredients comprising two or more particulate components. The resultant particles are usefully incorporated into powder coating compositions. The approach also finds utility in other applications, including but not limited to the food, drug, and cosmetics industry. Fluidized particles are subjected to an intense, but relatively brief heating event. This causes associated particles to fusingly assemble into fused composite clusters.
摘要:
Aqueous dispersion adhesives of anionic polyurethanes which have high heat resistance and low activation temperature, even when employed without addition of a crosslinker. The polyurethane is the reaction product of an isocyanate terminated polyurethane prepolymer, and water. The polyurethane prepolymer is the reaction product of a polyol component and a diisocyanate component, the polyol component including:a sulfonated polyester polyol,a hydroxy carboxylic acid of the formula:(HO).sub.x R(COOH).sub.ywherein (R) represents a straight or branched, hydrocarbon radical containing 1 to 12 carbon atoms, and x and y represent values from 1 to 3, and optionally,a low molecular weight aliphatic diol having a molecular weight of from 60 to 400a non-sulfonated polyol,and the diisocyanate component being selected from the group consisting of aromatic diisocyanates, isopherone diisocyanate, hexamethylene diisocyanate and mixtures thereof. The dispersions are prepared by mixing prepolymer and water at a temperature of at least 60.degree. C. for sufficient time to fully react the isocyanate groups in a prepolymer self-extension reaction with water, typically at least 0.5 hour. The dispersions of the invention provide higher strength adhesive bonds than identical prepolymer dispersions extended with diamine chain extender, instead of water, after dispersion.