摘要:
Aqueous dispersions containing a polyurethane which contains less than 0.6% by weight, based on the polyurethane, of urea groups ##STR1## are used as adhesives.
摘要:
Copolymers are composed ofa) from 0.01 to 40% by weight of a copolymerized ethylenically unsaturated compound having at least one isocyanate group blocked with an oxime,b) from 30 to 99.99% by weight of at least one C.sub.1 -C.sub.20 -alkyl (meth)acrylate, one vinyl ester of carboxylic acids of 1 to 20 carbon atoms, one vinylaromatic of up to 20 carbon atoms, one ethylenically unsaturated nitrile of 3 to 6 carbon atoms, one vinyl halide or one nonaromatic hydrocarbon of 4 to 8 carbon atoms having at least 2 conjugated double bonds,c) from 0 to 30% by weight of at least one comonomer having at least one keto or aldehyde group andd) from 0 to 50% by weight of at least one further monomer.
摘要:
Aqueous dispersions containing a polyurethane and from 5 to 60% by weight, based on the polyurethane, of an adhesion-improving polymer, the polyurethane consisting essentially of(a) organic diisocyanates,(b) dihydroxy compounds which have a molecular weight of from more than 500 to 5,000 g/mol and contain no ionic groups or groups convertible into ionic groups,(c) compounds having one or two functional groups reactive toward isocyanate and at least one ionic group or group convertible into an ionic group and(d) compounds having at last 3 isocyante groups or at least 3 functional groups reactive toward isocyanate,(e) optionally compounds which differ from (c) and have two functional groups reactive toward isocyanate and a molecular weight of from 60 to 500 g/mol, the compounds (d) being used in amounts such that the functionality F of all components is from 2.01 to 2.5, and the polyurethane or a prepolymer thereof is prepared in a water-miscible solvent boiling below 100.degree. C. and, after addition of the adhesion-improving polymer, is dispersed in water.
摘要:
Aqueous dispersions of a copolymer obtained by free-radical polymerization and containing from 0.01 to 40% w/w of polymerized units of comonomers having at least one aldehyde or keto group, which dispersions contain at least one polyisocyanate in which the isocyanate groups are blocked by oximes.
摘要:
Emulsifier-free aqueous polyurethane dispersions are prepared by reacting (a) dihydroxy compounds, (b) diisocyanates and (c) chain extenders to give a prepolymer having terminal isocyanate groups, then reacting the prepolymer with (d) salts of aliphatic aminocarboxylic or -sulfonic acids or amino-containing or hydroxyl-containing tertiary ammonium salts, dispersing the resulting polyurethane in water and, if required, removing the organic solvent by distillation. In the process, an organic condensation resin which is dissolved in a solvent is admixed before the polyurethane obtained is dispersed in water.
摘要:
Copolymers are composed ofa) from 0.01 to 40% by weight of a copolymerized ethylenically unsaturated compound having at least one isocyanate group blocked with an oxime,b) from 30 to 99.99% by weight of at least one C.sub.1 -C.sub.20 -alkyl (meth)acrylate, one vinyl ester of carboxylic acids of 1 to 20 carbon atoms, one vinylaromatic of up to 20 carbon atoms, one ethylenically unsaturated nitrile of 3 to 6 carbon atoms, one vinyl halide or one nonaromatic hydrocarbon of 4 to 8 carbon atoms having at least 2 conjugated double bonds,c) from 0 to 30% by weight of at least one comonomer having at least one keto or aldehyde group andd) from 0 to 50% by weight of at least one further monomer.
摘要:
Nonaqueous polyisocyanate formulation containinga) one or more aliphatic polyisocyanates having a mean NCO functionality of from 2.5 to 3.5 andb) an amount, which ensures that the polyisocyanate is dispersible, of a reaction product of a diisocyanate selected from the group consisting of tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-diisocyanatocyclohexane, 4,4'-di-(isocyanatocyclohexyl)-methane, diisocyanatotrimethylhexane, diisocyanatotetramethylhexane, 1-isocyanato-3,3,5-trimethyl-5-(isocyanatomethyl)-cyclohexane, toluylene 2,4- and 2,6-diisocyanate, tetramethylxylylene diisocyanate, p-xylylene diisocyanate, 2,4'- and 4,4'-diisocyanatodiphenylmethane and a mixture of two or more of these diisocyanates with a monohydric or polyhydric polyalkylene ether alcohol where the alkylene groups are of 2 to 4 carbon atoms and which contains a polyether chain having 8 or more ethylene oxide units,are prepared and are used in aqueous coating materials and in adhesive dispersions.
摘要:
Aqueous polyurethane dispersions are prepared by reacting (a) dihydroxy compounds having a molecular weight of from 500 to 5,000, (b) diisocyanates and, if required, (c) chain extenders having at least two hydrogen atoms which are reactive toward isocyanate groups and a molecular weight of less than 300 in the melt or in the presence of a water-miscible, inert organic solvent (S) which boils below 100.degree. C. to give a prepolymer having terminal isocyanate groups, then reacting the prepolymer with (d) salts of aliphatic aminocarboxylic or aminosulfonic acids or tertiary ammonium salts and dispersing the resulting polyurethane in water, by a process in which, before the polyurethane obtained is dispersed in water, from 5 to 60 parts by weight, based on 100 parts by weight of the polyurethane, of a polymer (p) [sic]which is dissolved in a solvent (S') boiling below 100.degree. C. is admixed, with the exception of condensates of phenol with formaldehyde and of epichlorohydrin with bisphenol A, and said polyurethane dispersions are used as adhesives or coating materials.
摘要:
Aqueous dispersions containA) from 96.95 to 45% by weight of a polyurethane,B) from 3.0 to 50% by weight of a phenol/formaldehyde condensation resin or of an epoxy resin andC) from 0.05 to 5.0% by weight of an inorganic salt having a solubility of less than 1 g/l in water at 20.degree. C.,the percentages by weight being based on the sum of the components A), B) and C).
摘要:
Aqueous dispersions of polyurethanes consisting of(a) organic polyisocyanates,(b) polyesterpolyols having a molecular weight of from 500 to 5,000,(c) organic hydroxy compounds having a molecular weight of from 62 to 400 and two terminal groups which are reactive to isocyanate groups, as chain extenders, and(d) compounds containing ionic groups or groups which can be converted to ionic groups and one or more isocyanate groups or a hydroxyl or amino group which is reactive to isocyanate groups,which contain from 0.05 to 2 meq of ionic groups incorporated into the polyurethane via (d) per g of polyurethane are particularly suitable for adhesives when the chain extenders (c) are incorporated in an amount of from 1.5 to 8 moles per mole of polyols, and a minor amount of (a) can be replaced with monoisocyanates, and a minor amount of (b) with polyetherpolyols.