摘要:
Polymeric, catalytically active compounds comprising polymer chains to which imidazole groups are linked terminally or laterally are used as catalysts for the dimerization of isocyanates.
摘要:
The invention relates to a process for the preparation of CFC-free, flexible polyurethane foams or molded foams by reactingA) liquid polyisocyanate mixtures containing bonded urethane groups and having a content of NCO groups of from 20 to 30% by weight, these mixtures themselves being prepared by reacting a mixture of diphenylmethane diisocyanates and polyphenyl-polymethylene polyisocyanates (crude diphenylmethane diisocyanate) with a polyether-polyol mixture, having a hydroxyl number of from 120 to 25, of at least one polyoxypropylene glycol and at least one trifunctional polyoxypropylene-polyoxyethylene glycol having a content of ethylene oxide units of from 90 to 10% by weight or by reacting 4,4'-diphenylmethane diisocyanate (diphenylmethyl diisocyanate) or an diphenylmethane diisocyanate isomer mixture with said polyether-polyol mixture to give an NCO-containing quasi-prepolymer and diluting this quasi-prepolymer with crude diphenylmethane diisocyanate, withB) relatively high-molecular-weight polyhydroxyl compounds.
摘要:
Mixtures of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates (crude MDI) of reduced iodine color number are prepared by reacting the corresponding mixtures of diphenylmethanediamines and polyphenylpolymethylenepolyamines with phosgene in the presence of at least one inert organic solvent at elevated temperature, at least one monohydric or polyhydric polyoxyalkylene alcohol, preferably having a functionality of from 2 to 3, and advantageously having a hydroxyl number of from 20 to 1800, or mixtures thereof in an effective amount, expediently in an amount of from 0.1 to 10% by weight, based on the weight of the crude MDI, being introduced into the reaction mixture when the phosgenation is complete, the phosgene and the inert organic solvent then being removed, up to 5% by weight, based on the weight of crude MDI, of at least one phenol-based antioxidant and/or aryl phosphite being added, if desired to the reaction product, and the reaction mixture being heated.
摘要:
Polymeric, catalytically-active compounds having imidazole groups linked terminally and/or laterally to the polymer chain through reactive groups on the polymer chain are disclosed. The polymer chain is selected from the group consisting of polyether ketones; acidic, basic, or neutral ion exchange resins; polymeric isocyanates; polymers or copolymers containing maleic acid or maleic anhydride; and polymers containing benzyl halide groups.
摘要:
The invention relates to a process for the preparation of CFC-free, flexible polyurethane foams or molded foams by reactingA) liquid polyisocyanate mixtures containing bonded urethane groups and having a content of NCO groups of from 20 to 30% by weight, these mixtures themselves being prepared by reacting a mixture of diphenylmethane diisocyanates and polyphenyl-polymethylene polyisocyanates (crude diphenylmethane diisocyanate) with a polyether-polyol mixture, having a hydroxyl number of from 120 to 25, of at least one polyoxypropylene glycol and at least one trifunctional polyoxypropylene-polyoxyethylene glycol having a content of ethylene oxide units of from 90 to 10% by weight or by reacting 4,4'-diphenylmethane diisocyanate (diphenylmethyl diisocyanate) or an diphenylmethane diisocyanate isomer mixture with said polyether-polyol mixture to give an NCO-containing quasi-prepolymer and diluting this quasi-prepolymer with crude diphenylmethane diisocyanate, withB) relatively high-molecular-weight polyhydroxyl compounds.
摘要:
The invention relates to a process for the preparation of CFC-free, flexible polyurethane foams or molded foams by reactingA) liquid polyisocyanate mixtures containing bonded urethane groups and having a content of NCO groups of from 20 to 30% by weight, these mixtures themselves being prepared by reacting a mixture of diphenylmethane diisocyanates and polyphenyl-polymethylene polyisocyanates (crude diphenylmethane diisocyanate) with a polyether-polyol mixture, having a hydroxyl number of from 120 to 25, of at least one polyoxypropylene glycol and at least one trifunctional polyoxypropylene-polyoxyethylene glycol having a content of ethylene oxide units of from 90 to 10% by weight or by reacting 4,4'-diphenylmethane diisocyanate (diphenylmethyl diisocyanate) or an diphenylmethane diisocyanate isomer mixture with said polyether-polyol mixture to give an NCO-containing quasi-prepolymer and diluting this quasi-prepolymer with crude diphenylmethane diisocyanate, withB) relatively high-molecular-weight polyhydroxyl compounds.
摘要:
In a process for preparing isocyanates having a light color by reacting the corresponding amines with phosgene, the amines are treated with solid inorganic substances containing Lewis acid and/or Bronsted acid centers prior to the reaction with the phosgene.
摘要翻译:在通过使相应的胺与光气反应制备具有浅色的异氰酸酯的方法中,在与光气反应之前,将胺与含有路易斯酸和/或Br + E,O + EE + nsted酸中心的固体无机物质进行处理 。
摘要:
The present invention relates to a process for preparing high-functionality polyetherols by reacting at least one trifunctional or higher-functionality alcohol and if appropriate further di- and/or monofunctional alcohols and/or modifying reagents, with the aid of acidic catalysts, where the trifunctional or higher-functionality alcohol is not glycerol. The present invention further relates to high-functionality polyetherols obtainable by such a process and to the use of these high-functionality polyetherols as adhesion promoters, thixotropic agents, rheology modifiers of polymers, phase transfer reagents, micro- or nanocontainers for biologically active compounds, for example for active medical ingredients, biocides, herbicides or fungicides, as pigment dispersants, an additive in printing inks or as structural units for preparing polyaddition or polycondensation polymers or for treatment of seed.
摘要:
Branched polyesters with sulfonate groups can be obtained by reacting components A, B, optionally C, and optionally D to yield branched polyesters, then reacting these branched polyesters with hydrogen sulfite. Component A is at least one α,β-olefinically unsaturated dicarboxylic acid, component B is at least one di- or higher-functional alcohol, optional component C is at least one di- or higher-functional carboxylic acid or hydroxycarboxylic acid without an α,β-olefinically unsaturated bond, and optional component D is at least one compound of formula CH3(—O—CH2—CH2)n—OH. In reacting the branched polyesters with hydrogen sulfite, a molar amount of hydrogen sulfite is at most 95 mol %, based on an amount of α,β-olefinically unsaturated dicarboxylic acid.
摘要:
The present invention relates to new high-functionality, highly branched or hyperbranched polylysines, to processes for preparing them, and to their use.