Abstract: The present invention relates to a process for the production of polyhydroxyl compounds having a hydroxyl group content of 2 to 10% by weight and a viscosity at 23.degree. C. of 250 to 80,000 mPa.s by the radically initiated polymerization at a reaction temperature of 80.degree. to 220.degree. C. ofa) 100 parts by weight of a mixture of olefinically unsaturated monomers containing at least 1% by weight of monomers containing alcoholic hydroxyl groups in the presence ofb) 5 to 500 total parts by weight, which may be present at the beginning of the reaction or added during the reaction, of one or more cyclic compounds which, in the presence of initiator compounds containing alcoholic hydroxyl groups, are capable of a ring-opening polymerization reaction andc) 2 to 300 parts by weight, which may be present at the beginning of the reaction or added during the reaction, of one or more polyhydric alcohols having a molecular weight of 62 to 1000.

Abstract: The present invention relates to a process for recovering and recycling the organic binder components accumulating as overspray during the spraying of a solvent-containing, two-component polyurethane lacquer or a solvent-containing, moisture-curing, one-component polyurethane lacquer byi) washing the overspray out of the exhaust air of a coating plant with the aid of an aqueous medium which a) contains in dissolved or dispersed form compounds that exhibit greater reactivity towards isocyanate groups than either water or the isocyanate-reactive groups present in two-component polyurethane lacquers, and b) may contain emulsifiers,ii) isolating the chemically modified overspray formed in step (i) in the form of lacquer sludge by treatment with coagulating agents, which may be present in the aqueous medium,iii) mixing the lacquer sludge, containing fully reacted lacquer constituents, coagulating agents and water, optionally after a portion of the water is removed, with an organic solvent andiv) separating the org

Abstract: The present invention relates to a process for recovering and recycling the organic binder components accumulating during the spraying of a solvent-containing, two-component polyurethane coating or a solvent-containing, moisture-curing one-component polyurethane coating byi) forming a coatings slurry containing the organic binder components, water and a coagulating agent,ii) mixing the coatings slurry, optionally after removing a portion of the water, with an organic solvent which is inert towards isocyanate groups,iii) reacting the free isocyanate groups present in the mixture obtained in step (ii) with a compound containing one isocyanate-reactive group which is more reactive with isocyanate groups than both water and the isocyanate-reactive component of the two-component polyurethane coating, if present, andiv) removing any remaining water and insoluble components from the organic phase accumulating in step (iii) and recovering the organic phase containing the organic binder components.