Preparation of flexible polyurethane foams

Abstract

Flexible polyurethane foams are prepared by reacting organic and/or modified organic polyisocyanates (a) with a polyetherol mixture (b) and, if required, further compounds (c) having hydrogen atoms reactive toward isocyanates, in the presence of water and/or other blowing agents (d), catalysts (e) and, if required, further assistants and additives (f), by a process in which the polyetherol mixture (b) consists of b1) at least one polyetherol which is at least difunctional, has an OH number of from 20 to 100 mg KOH/g and is based on propylene oxide and/or butylene oxide and ethylene oxide, having an ethylene oxide content of more than 40% by weight, based on the total amount of alkylene oxide used, and, if required, further polyetherols which are at least difunctional, are based on propylene oxide and/or butylene oxide and ethylene oxide and have an OH number of from 20 to 160 mg KOH/g and b2) at least one difunctional to hexafunctional polyetherol based on propylene oxide and/or butylene oxide and having an OH number of less than 800 mg KOH/g and the foams are prepared with indices of less than 110, the amount by weight of (b1) being greater than that of (b2). The flexible polyurethane foams prepared by this process are used for upholstery purposes, and insulation purposes, in vehicle construction and in the medical and hygiene sector.

Dependencies are inferred from the claim text.