Hydrophilic aliphatic polyurethane foams

摘要

Producing hydrophilic, aliphatic polyurethane foam (I), comprises providing, foaming and curing a composition (A) comprising (a) isocyanate functional prepolymer, (b) 4- or 6-membered heterocyclic oligomer of low molecular weight aliphatic diisocyanates, (c) water, (d) optionally a catalyst, (e) 8-22C monocarboxylic acid or 12-44C-dicarboxylic acid or its ammonium- or alkali salts, (f) optionally surfactant, (g) optionally mono- or polyhydric alcohol and (h) optionally hydrophilic polyisocyanate obtained by reacting (h1) aliphatic diisocyanates and (h2) monofunctional polyalkylene oxide. Producing hydrophilic, aliphatic polyurethane foam (I), comprises providing, foaming and curing a composition (A) comprising (a) 100 parts by weight of isocyanate functional prepolymer with a content of low molecular weight, aliphatic diisocyanates with a molar mass of 140-278 g/mole of less than 1 wt.%, based on the prepolymer, which is obtained by reacting (a1) low molecular weight, aliphatic diisocyanates having a molecular weight of 140-278 g/mole and (a2) di- to hexa-functional polyalkylene oxide with a hydroxyl number of 22.5-112 mg potassium hydroxide (KOH)/g and an ethylene oxide content of 50-100 mol.%, based on the total amount of oxyalkylene groups, (b) greater than 30-100 parts by weight of 4- or 6-membered heterocyclic oligomer of low molecular weight, aliphatic diisocyanates with a molecular weight of 140-278 g/mole, (c) 0.1-200 parts by weight of water, (d) optionally 0-1 part by weight of catalyst, (e) 0.01-5 parts by weight of 8-22C monocarboxylic acid or 12-44C-dicarboxylic acid or its ammonium- or alkali salts, (f) optionally 0-10 parts by weight of surfactant, (g) optionally 0-20 parts by weight of mono- or polyhydric alcohol and (h) optionally 0-60 parts by weight of hydrophilic polyisocyanate obtained by reacting (h1) low molecular weight, aliphatic diisocyanates having a molecular weight of 140-278 g/mole and/or polyisocyanates having an isocyanate functionality of 2-6 produced from (h1) and (h2) monofunctional polyalkylene oxide with a hydroxyl number of 10-250, and an ethylene oxide content of 50-100 mol.%, based on the total amount of oxyalkylene groups. Independent claims are included for: (1) the composition (A); and (2) (I), obtained from (A) or by the above process.