Preparation of in situ-reticulated flexible polyurethane foams

Abstract

Reticulated 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 further assistants and additives (f), by a process in which the polyetherol mixture (b) comprises b1) at least one difunctional or polyfunctional polyetherol having an OH number of from 20 to 150 mg KOH/g, based on propylene oxide and/or butylene oxide and ethylene oxide and having an ethylene oxide content of more than 40% by weight, based on the total amount of alkylene oxide used, (b1.1) and, if required, further difunctional or polyfunctional polyetherols having an OH number of from 20 to 150 mg KOH/g, based on propylene oxide and/or butylene oxide and ethylene oxide and having an ethylene oxide content of not more than 40% by weight, based on the total amount of alkylene oxide used, which have a content of primary OH groups of more than 40%, (b1.2), with total amounts of the component (b1) of at least 70% by weight, based on the total weight of the component (b), (b1.1) being present in amounts of at least 50% by weight, based on the total weight of the component (b), and b2) at least one difunctional or polyfunctional polyetherol based on propylene oxide and/or butylene oxide and having an OH number of more than 25 mg KOH/g, in amounts of not more than 30% by weight, based on the total weight of the component (b), and silicone stabilizers are used in amounts of from 0.02 to 5% by weight, based on the total weight of the components (b) to f). The reticulated flexible polyurethane foams themselves prepared in this manner are used for upholstery purposes, for cavity filling and as support medium and filter medium.

Dependencies are inferred from the claim text.