摘要:
The present invention relates to a process for the production of flexible polyurethane foams by reaction of a) at least one compound having at least two isocyanate-reactive hydrogen atoms, with b) polyisocyanates, wherein the compund used as said compound having at least two isocyanate-reactive hydrogen atoms a) comprises at least one block polyoxypropylene/polyoxyethylene/polyol having a hydroxyl value of from 25 to 45 mg KOH/g and a content of terminally bound ethylene oxide units of from 15 to 17 wt %, based on the total amount of the alkylene oxide, obtained by attachment of ethylene oxide and propylene oxide to an initiator having an average functionality of 3.
摘要:
Polyurethane foams are prepared by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms reactive with isocyanate groups, by a process in which the polyisocyanates a) are aliphatic di- or polyisocyanates and the compounds having at least two hydrogen atoms reactive with isocyanate groups b) contain at least one acrylate polyol.
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:
In a process for producing flexible polyurethane foams by the reaction known per se of polyisocyanates with compounds containing at least two hydrogen atoms which react with isocyanate, the reaction is carried out in the presence of cyclic or heterocyclic compounds containing at least one reactive hydrogen atom.
摘要:
Two-component polyurethane systems composed of an at least bifunctional polyisocyanate component and a polyol component have a polyol component which comprises at least one hydroxyl-containing cyclic acetal and/or ketal.
摘要:
The present invention relates to a process for the preparation of flexible, soft polyurethane foams having viscoelastic, structure-borne soundproofing properties in a temperature range of from -20.degree. C. to +80.degree. C. by reactinga) a polyoxyalkylene-polyol mixture containingai) block polyoxypropylene-polyoxyethylene-polyol mixture having a hydroxyl number of from 14 to 65 and containing from 2 to 9% by weight of terminal ethylene oxide units, based on the weight of the polyoxypropylene units, prepared by anionic polymerization, at elevated temperatures, of 1,2-propyleneoxide onto an initiator molecule mixture having a mean functionality of from 2.3 to 2.8, comprising water and glycerol and/or trimethylolpropane, and polymerization of acylene oxide onto the resultant polyoxypropylene adduct, andaii) one or more difunctional and/or trifunctional polyoxypropylene-polyoxyethylene-polyol containing from 60 to 85% by weight of oxyethylene units, based on the total weight of polymerized alkylene oxide units, and having a hydroxyl number of from 20 to 80, andb) if desired low-molecular-weight chain extenders withc) organic and/or modified organic polyisocyanates in the presence ofd) catalysts,e) blowing agents, preferably water, and, if desired,f) auxiliaries and/or additives,and to the polyoxyalkylene-polyol mixtures (a) which can be used for this purpose.
摘要:
Flexible polyurethane foams having low compressive strength and relatively good tensile strength are prepared by reactinga) a block polyoxypropylenepolyoxyethylenepolyol mixture which has a hydroxyl number of from 14 to 65, contains from 2 to 9% by weight, based on the weight of the polyoxypropylene units, of ethylene oxide units bonded in the terminal position and is prepared by anionic polymerization of the alkylene oxides with an initiator mixture having an average functionality of from 2.3 to 2.8 and consisting of water and glycerol and/or trimethylolpropane, or a mixture of these block polyoxypropylenepolyoxyethylenepolyol mixtures with bi- and/or trifunctional polyoxypropylenepolyoxyethylenepolyols having a hydroxyl number of from 20 to 70, andb) if required, low molecular weight chain extenders withc) organic and/or modified organic polyisocyanates in the presence ofd) catalysts,e) blowing agents, preferably water, and if required,f) assistants and/or additives.
摘要:
A process for producing high resilience flexible polyurethane foams. The process includes forming a mixture of (a) isocyanate prepolymer, (b) polymeric compounds having isocyanate-reactive groups, (c) castor oil, (d) optionally chain-extending and/or crosslinking agents, (e) catalysts, (f) blowing agents, and optionally (g) additives, and reacting the mixture to form the flexible polyurethane foam. More than 5 wt % of (c) is used, based on the total weight of components (b) to (g), and (a) is obtained by mixing diphenylmethane diisocyanate (a1) and polyol 1 (a2) and also optionally further polyols, chain extenders and/or crosslinkers, where (a2) includes a polyalkylene oxide polyol having a hydroxyl number of 30 to 60, an average functionality of 2.3 to 3.2 and a propylene oxide fraction, based on the alkylene oxide content, of 70 to 100 wt %. A polyurethane foam obtained by the process, and the use of such a foam as an auto seat.
摘要:
The present invention relates to a process for preparing polyether polyols, in which at least one hydroxyl-comprising fatty acid ester and/or at least one hydroxyl-modified fatty acid ester is reacted with the aid of a double metal cyanide catalyst in at least two process sections with in each case a mixture of ethylene oxide and at least one further alkylene oxide different from ethylene oxide.
摘要:
The present invention relates to a process for the preparation of CFC-free, flexible polyurethane (molded) foams by reactingA) liquid polyisocyanate mixtures containing bonded urethane groups having a content of NCO groups of from 22 to 30% by weight which are themselves prepared by reacting a mixture of diphenylmethane diisocyanates and polyphenyl-polymethylene polyisocyanates having a content of diphenylmethane diisocyanate isomers of from 55 to 99% by weight, based on the total weight, with at least one trifunctional polyoxypropylene-polyol having a hydroxyl number of from 20 to 60, withB) relatively high-molecular-weight polyhydroxyl compounds and, if desired,C) 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,and to the polyisocyanate mixtures (A) modified by means of urethane groups which can be used according to the invention.