GB1001458A - Catalysts for isocyanate reactions - Google Patents

Abstract

The reaction between a polyisocyanate or polyisothiocyanate and a compound containing active hydrogen is catalysed by a mixture of a quaternary ammonium, quaternary phosphonium or ternary sulphonium salt of a strong acid and an organic metal compound of the type used as catalyst in polyurethane manufacture, the said quaternary or ternary salt and the said organic metal compound both being used in an amount of from 0.05 to 5% by weight of the compound containing active hydrogen. Compounds specified are tri-n-butyl methyl phosphonium iodide, triphenyl methyl phosphonium iodide, thio-(tetrabutyl phosphonium) sulphate, tetrabutyl phosphonium chloride, N,N-dimethylpiperidinium iodide, tetrakis (hydroxymethyl) phosphonium chloride, phenyl-ethylcyclo-tetramethylene phosphonium iodide, N-allyl - N - ethylpiperidinium bromide and trimethylsulphonium iodide. Organic metal compounds are: stannous octoate, zinc octoate, lead octoate and dibutyl tin dilaurate. Conventional organic polyisocyanates are listed. The active hydrogen-containing group may be hydroxyl, carboxylic acid, amide, urethane or urea groups. Cellular and non-cellular polyurethanes may be produced from polyesters, polyesteramides or polyethers. In Example (2), a solution containing a methyl phenylsiloxane, stannous octoate and tolylene diisocyanate was added to a mixture of N-allyl N-ethylpiperidinium bromide, water and a linear polypropylene glycol of MW 2000 to obtain a cellular polyurethane.ALSO:The reaction between an organic polyisocyanate or polyisothiocyanate and a compound containing active hydrogen is catalysed by a mixture of a quaternary ammonium quaternary phosphonium or ternary sulphonium part of a strong acid and an organic metal compound of the type used as catalyst in polyurethane manufacture, the said quaternary or ternary salt and the said organic metal compound both being used in an amount of from 0.05% to 5% by weight of the compound containing active hydrogen. Compounds specified are tri-n-butylmethyl phosphonium iodide, triphenyl-methyl phosphonium iodide, bis-(tetrabutyl phosphonium) sulphate, tetrabutyl phosphonium chloride, N,N-dimethylpiperidinium iodide, tetrakis(hydroxymethyl) phosphonium chloride, phenylethyl - cyclo - tetramethylene phosphonium iodide, N-allyl-N ethyl piperidinium bromide and trimethylsulphonium iodide. Organic metal compounds may be stannous octoate, zinc octoate, lead octoate, and dibutyltin dilaurate. The active hydrogen-containing group may be: hydroxyl, carboxylic acid, amide, urethane or urea groups. In an Example (1) the reaction between dry sec.-butanol and a mixture of tolylene diisocyanates to form a mixture of tolylene bis-(sec.-butyl carbamates) was catalysed by different catalyst mixtures. In comparison examples the reaction was repeated with no catalyst and with the ternary or quaternary salts but omitting the organic metal compounds.