COMPOSITION FOR ONE-COMPONENT POLYURETHANE FOAMS HAVING LOW FREE MONOMERIC MDI CONTENT

摘要

A one component precursor for the polymeric foam (OCF) composition comprising a very low amount of free monomeric MDI. The present OCF composition may be obtained without any free MDI removal step, and without the addition of extra solvent to compensate for the substantially lower amount of free MDI, compared with traditional compositions. The present composition comprises a source of free NCO of functionality of at least 2.6, a tri- or higher functional alcohol, all polyols being characterized by a rather low molecular weight and at least a specific mono-functional alcohol as well as an isocyanate end-capped prepolymer of toluene diisocyanate (=end capped TDI). The OCF composition is suitable for being dispensed from a pressurized can with a blowing agent.

主权项

1. A kit of parts for the reduction of free monomeric diphenylmethane diisocyanate (MDI) in one component polyurethane precursor mixtures comprising:
(a) a mono-functional alcohol having a molecular weight of at least about 130 g/mol, preferably having a branched paraffinic structure, and (b) an isocyanate end-capped prepolymer of toluene diisocyanate (=end capped TDI), wherein the monofunctional alcohol is a member selected from the group consisting of 2-ethyl-hexanol, ester of vegetal oil containing one secondary hydroxyl group, such as ricinoleic ester, and mixtures thereof.