Abstract: Moisture-cure of a polyurethane prepolymer based on an aliphatic diisocyanate is readily accomplished when a prepolymer is first made from a polyhydroxy compound and an isocyanate group-terminated adduct of the aliphatic diisocyanate with a monosecondary or disecondary diamine obtained by reaction of an aliphatic diamine with an activated monoethylenic compound. Tetravalent organotin compounds are particularly good catalysts for the moisture cure. Moisture-curable polyurethane compositions of the present invention are useful in polyurethane coatings, especially for decorative surfaces, such as flooring.

Abstract: An aqueous latex, having high colloidal stability against coagulation upon addition thereto of ionic materials and having excellent adhesive characteristics for bonding metal foil to paper to form laminates, is prepared by polymerizing, in an emulsion substantially free of carboxylate soaps, (1) an aqueous suspension of chloroprene monomer optionally containing about 0.4 to 10 mole percent of alpha, beta-unsaturated carboxylic acid monomer, based on the total monomer content, (2) in the presence of (a) about 3-10 parts of polyvinyl alcohol and (b) about 0.3-2 parts of an organic, sulfur-containing chain-transfer agent of the group consisting of dialkyl xanthogen disulfides and alkyl mercaptans, both (a) and (b) being expressed in parts by weight based on 100 parts by weight of monomer (1). The polymer so produced contains 10-95% gel polymer, and the polyvinyl alcohol is present therein in a form such that it is not completely recoverable by extraction with water.