摘要:
Low-density hydrophilic 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 difunctional or polyfunctional polyetherol 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, an OH number of from 20 to 120 mg KOH/g and a proportion of primary OH groups of more than 20% and b2) at least one difunctional or polyfunctional polyetherol based on propylene oxide and/or butylene oxide and, if required, ethylene oxide, the ethylene oxide content being not more than 40% by weight, and having an OH number of more than 25 mg KOH/g, water in amounts of up to 15% by weight, based on the total weight of the components (b) to (f), and a mixture of gel catalysts and blowing catalysts are used and the foaming is effected in an index range of from 20 to 120. Furthermore, the flexible polyurethane foams themselves produced in this manner are used as upholstery material, as energy-absorbing material and in the cosmetics and hygiene sectors.
摘要:
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.
摘要:
In a process for producing sound-absorbing PUR foams having an adhesive surface by reacting organic and/or modified organic polyisocyanates (a) with a polyetherol mixture (b) and, if desired, further compounds (c) bearing hydrogen atoms which are reactive toward isocyanates, in the presence of water and/or other blowing agents (d), catalysts (e) and, if desired, further auxiliaries and additives (f), the polyetherol mixture (b) comprises b1) at least one bifunctional to eight-functional polyetherol based on ethylene oxide and propylene oxide and having an OH number of from 20 to 80 mg KOH/g and a proportion of primary OH groups of >50%, b2) at least one polyetherol based on ethylene oxide and propylene oxide and/or butylene oxide and a bifunctional to eight-functional initiator and having an OH number of from 20 to 80 mg KOH/g, where the proportion of ethylene oxide in the polyetherol is >30% by weight, in amounts of from 10 to 50 parts by weight, and b3) at least one polyetherol based on propylene oxide and/or butylene oxide and, if desired, ethylene oxide and a bifunctional to eight-functional initiator and having an OH number of from 30 to 400 mg KOH/g, where the proportion of ethylene oxide in the polyetherol is
摘要:
Sound-damping and energy-absorbing flexible PUR foams are produced by reacting organic and/or modified organic polyisocyanates (a) with a polyetherol mixture (b) and, if desired, further compounds (c) bearing hydrogen atoms which are reactive toward isocyanates, in the presence of water and/or other blowing agents (d), catalysts (e) and, if desired, further auxiliaries and additives (f).
摘要:
A homogeneous, demixing-stable polyol component comprising at least two relatively high molecular weight compounds containing at least two reactive hydrogen atoms and, if desired, low molecular weight chain extenders and/or crosslinkers and also, if desired, blowing agents, catalysts and further auxiliaries and/or additives is prepared by adding at least one amine and at least one organic and/or modified organic isocyanate to this component.This polyol component is useful for producing polyurethanes, in particular compact and foamed polyurethanes.
摘要:
A stable dispersion of melamine in polyol components comprising at least one relatively high molecular weight compound containing at least two reactive hydrogen atoms and, if desired, low molecular weight chain extenders and/or crosslinkers, blowing agents, catalysts, flame retardants and also further auxiliaries and/or additives is prepared by using the melamine in combination with at least one amine and at least one organic and/or modified organic isocyanate. Such a dispersion can be used for producing flame-resistant polyurethane foams
摘要:
A process for the production of cellular polyurethanes by reactinga) at least one organic and/or modified organic polyisocyanate,b) at least one relatively high-molecular-weight compound containing at least two reactive hydrogen atoms, if desiredc) low-molecular-weight chain extenders and/or crosslinking agents,in the presence ofd) blowing agents,e) catalysts, and, if desired,f) auxiliaries and/or additives,wherein the blowing agent d) is at least one acetal.
摘要:
The invention relates to polyurethane-based, compact moldings or moldings having a cellular core and a compacted surface which comprise crosslinked poly(meth)acrylic acid, poly(meth)acrylic acid salts and/or poly(meth)acrylamides, to a process for their production, and to their use as shoe or shoe sole material.
摘要:
The invention relates to polyurethane-based, compact moldings or moldings having a cellular core and a compacted surface which comprise crosslinked poly(meth)acrylic acid, poly(meth)acrylic acid salts and/or poly(meth)acrylamides, to a process for their production, and to their use as shoe or shoe sole material.
摘要:
Prepolymers which contain isocyanate groups, have an NCO content of at least 30.0% by weight and can be prepared by reacting an isocyanate mixture consisting predominantly of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates and having a proportion of two-ring isomers of not more than 74% by weight with at least 4-functional polyols or a mixture of polyols having a mean functionality of at least 4, where the polyols or polyol mixtures have a hydroxyl number of from 200 to 1650 mg KOH/g and a number average molecular weight of less than 1100 g/mol. The present invention also provides a process for preparing these prepolymers containing isocyanate groups, provides for their use for producing polyurethanes and provides a process for producing polyurethanes by reacting at least one novel prepolymer containing isocyanate groups, if desired in admixture with further organic and/or modified organic isocyanates (a), with compounds having at least two reactive hydrogen atoms (b) in the presence of, if desired, blowing agents (c), catalysts (d) and, if desired, further auxiliaries and/or additives (e).