A process for the production of sponges from polyurethanes

摘要

In a process for the production of polyurethane sponges by foaming one or more polyesters and one or more diisocyanates in the presence of water, the foaming takes place with the addition of waste polyurethane foam and one or more partially saponified esters which have been produced by reacting a tertiary amine containing one or more free hydroxyl groups with a monofunctional or polyfunctional carboxylic acid and partially saponifying the ester thus produced to form a product having an acid number of from 60 to 120. The waste foam may be subjected to preliminary treatment under heat and pressure, or by dissolving it in a solvent having a boiling point of at least 180 DEG C. and then distilling off the solvent. Alternatively, the waste polyurethane is dissolved in the polyester or diisocyanate before the foaming. In the accelerator the tertiary amine component may be N-diethylethanolamine or methyl diethanolamine and the carboxylic acid component can be acetic or adipic acid. In the examples the waste material for further use is (1) dissolved in the polyester reactant (an adipic acid/trimethylol propane/1,3-butylene glycol reaction product); (2) dissolved in glycerine at 230 DEG to 270 DEG C. and the glycerine is then distilled off; (3) is heated at 260 DEG to 270 DEG C. under pressure; (5) is thermally liquefied. Specification 805,561 is referred to.ALSO:In a process for the production of polyurethane sponges by foaming one or more polyesters and one or more diisocyanates in the presence of water, the foaming takes place with the addition of waste polyurethane foam and one or more partially saponified esters which have been produced by reacting a tertiary amine containing one or more free hydroxy groups with a monofunctional or polyfunctional carboxylic acid and partially saponifying the ester thus produced to form a product having an acid number of from 60 to 120. The waste foam may be subjected to preliminary treatment under heat and pressure, or by dissolving it in a solvent having a boiling point of at least 180 DEG C. and then distilling off the solvent. Alternatively the waste polyurethane is dissolved in the polyester or diisocyanate before the foaming. In the accelerator the tertiary amine component may be N-diethyl-ethanolamine or methyl diethanolamine and the carboxylic acid component may be acetic or adipic acid. In the examples the waste material is (1) dissolved in the polyester (an adipic acid/trimethylol propane/1 : 3-butylene glycol reaction product); (2) dissolved in glycerine at 230 DEG to 270 DEG C. and the glycerine is then distilled off; (3) is heated at 260 DEG to 270 DEG C. under pressure; (5) is thermally liquefied. Specification 805,561 [Group IV(a)], is referred to.