| abstract |
This invention concerns a process for producing storage stable dispersions of toluylene diisocyanate urethane dione encapsulated with primary aliphatic polyamines using surface adduct formation in a one-pot reaction. To that effect, (a) in the presence of a dimerization catalyst, a monomer toluene diisocyanate is brought to reaction in a polyalcohol or a liquid medium which is inert in the isocyanate reaction and of moderate or low polarity at temperatures below 30 DEG C; (b) subsequently, the dimerization catalyst is deactivated; (c) then, the reaction product is reacted with a primary amine representing 10 to 30 mol % of the toluene diisocyanate used; (d) subsequently, at least one primary polyamine in an amount of 40 to 80 moles %, relative to the free isocyanate group, is added. The dispersions produced can be used for the production of a polyurethane adhesive or a polyurethane sealing material or a polyurethane coating material which is stable in storage and can be heat-cured by mixing it with at least one polyalcohol and/or polyamine with a molecular weight of 100 to 20,000. |