Use of polyamine- and/or polyalkanolamine-based carboxylic acid derivatives in aqueous polyurethane dispersions
The use of polyamine- and/or polyalkanolamine-based carboxylic acid derivatives as additives in aqueous polymer dispersions for production of porous polymer coatings, preferably for production of porous polyurethane coatings, is described.
1 . An aqueous polyurethane dispersion, comprising polyamine- and/or polyalkanolamine-based carboxylic acid derivatives obtainable by a process consisting of reacting one or more polyamines selected from the group consisting of diethylenetriamine, triethylenetetraamines, tetraethylenepentamines, pentaethyleneheptaamine, dipropylenetriamine, tripropylenetetraamine, spermine, spermidine, and N-alkylated or N-methylated derivatives of these compounds, and/or one or more polyalkanolamines selected from the group consisting of polydipropanolamine, polydiisopropanolamine, polytriethanolamine, polytripropanolamine, polytriisopropanolamine, and polyetheramine, with at least one acyl group donor comprising rapeseed oil acid, soya fatty acid, sunflower fatty acid, peanut fatty acid, palmitic acid, stearic acid, or tall oil fatty acid, wherein the solids content of the dispersion is in the range of 20-70% by weight based on the overall dispersion, and wherein the concentration of the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives is in the range of 0.2-20% by weight based on the total weight of the aqueous polyurethane dispersion.
2 . The aqueous polyurethane dispersion of claim 1 , wherein the polyalkanolamine is selected from the group consisting of: polydipropanolamine, polydiisoproanolamine, polytriethanolamine, polytripropanolamine, and mixtures thereof.
3 . The aqueous polyurethane dispersion of claim 1 , wherein the polyamine-based carboxylic acid derivatives are reaction products of at least one polyamine selected from the group consisting of: diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.
4 . The aqueous polyurethane dispersion of claim 1 , wherein the polyamine-based carboxylic acid derivatives are reaction products of (co) polymers bearing amine groups with at least one carboxylic acid, where the (co) polymers bearing amine groups have at least one repeat unit A of general formula 2:
and/or at least one repeat unit B of general formula 3:
wherein the R 4 radicals are identical or different monovalent aliphatic or aromatic, saturated or unsaturated hydrocarbon radicals having 1 to 10 carbon atoms, or hydrogen, and with the proviso that the (co) polymer is selected from polyamines listed in claim 1 .
5 . The aqueous polyurethane dispersion of claim 1 , wherein, in the preparation of polyamine- and/or polyalkanolamine-based carboxylic acid derivatives, polyamine and/or polyalkanolamine and carboxylic acids are reacted in such a way that the molar ratio of amine and OH functions reactive toward carboxylic acids to carboxylic acids is in the range of 5:1-1.5:1.
6 . The aqueous polyurethane dispersion of claim 1 , wherein the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives are used in combination with at least one further cosurfactant, selected from the group consisting of: fatty alcohols, fatty acid amides, ethylene oxide-propylene oxide block copolymers, betaines, amine oxides, quaternary ammonium surfactants, amphoacetates, ammonium and/or alkali metal salts of fatty acids, alkyl sulfates, alkyl ether sulfates, alkylsulfonates, alkylbenzenesulfonates, alkyl phosphates, alkyl sulfosuccinates, alkyl sulfosuccinamates, alkyl sarcosinates and/or silicone-based cosurfactants and mixtures of these substances.
7 . The aqueous polyurethane dispersion of claim 1 , wherein the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives are used in combination with at least one cosurfactant, wherein said cosurfactant is a free fatty alcohol having 12 to 40 carbon atoms, an alkyl sulfate having 12 to 40 carbon atoms, or a mixture of these substances.
8 . The aqueous polyurethane dispersion of claim 1 , wherein the concentration of the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives based on the total weight of the aqueous polyurethane dispersion is in the range of 0.5-10% by weight.
9 . The aqueous polyurethane dispersion of claim 2 , wherein, in the preparation of polyamine- and/or polyalkanolamine-based carboxylic acid derivatives, polyamine and/or polyalkanolamine and carboxylic acids are reacted in such a way that the molar ratio of amine and OH functions reactive toward carboxylic acids to carboxylic acids is in the range of 5:1-1.5:1.
10 . The aqueous polyurethane dispersion of claim 2 , wherein the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives are used in combination with at least one further cosurfactant, selected from the group consisting of: fatty alcohols, fatty acid amides, ethylene oxide-propylene oxide block copolymers, betaines, amine oxides, quaternary ammonium surfactants, amphoacetates, ammonium and/or alkali metal salts of fatty acids, alkyl sulfates, alkyl ether sulfates, alkylsulfonates, alkylbenzenesulfonates, alkyl phosphates, alkyl sulfosuccinates, alkyl sulfosuccinamates, alkyl sarcosinates and/or silicone-based cosurfactants and mixtures of these substances.
11 . The aqueous polyurethane dispersion of claim 2 , wherein the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives are used in combination with at least one cosurfactant, wherein said cosurfactant is a free fatty alcohol having 12 to 40 carbon atoms, an alkyl sulfate having 12 to 40 carbon atoms, or a mixture of these substances.
12 . The aqueous polyurethane dispersion of claim 2 , wherein the concentration of the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives based on the total weight of the aqueous polyurethane dispersion is in the range of 0.5-10% by weight.
13 . The aqueous polyurethane dispersion of claim 3 , wherein the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives are used in combination with at least one further cosurfactant, selected from the group consisting of: fatty alcohols, fatty acid amides, ethylene oxide-propylene oxide block copolymers, betaines, amine oxides, quaternary ammonium surfactants, amphoacetates, ammonium and/or alkali metal salts of fatty acids, alkyl sulfates, alkyl ether sulfates, alkylsulfonates, alkylbenzenesulfonates, alkyl phosphates, alkyl sulfosuccinates, alkyl sulfosuccinamates, alkyl sarcosinates and/or silicone-based cosurfactants and mixtures of these substances.
14 . The aqueous polyurethane dispersion of claim 3 , wherein the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives are used in combination with at least one cosurfactant, wherein said cosurfactant is a free fatty alcohol having 12 to 40 carbon atoms, an alkyl sulfate having 12 to 40 carbon atoms, or a mixture of these substances.
15 . The aqueous polyurethane dispersion of claim 3 , wherein the concentration of the polyamine- and/or polyalkanolamine-based carboxylic acid derivatives based on the total weight of the aqueous polyurethane dispersion is in the range of 0.5-10% by weight.
16 . A process for producing a porous polyurethane coating, comprising the steps of:
a) providing a mixture comprising at least one aqueous polyurethane dispersion, according to claim 1 ;
b) foaming the mixture to give a foam;
c) optionally adding at least one thickener to adjust the viscosity of the wet foam;
d) applying a coating of the foamed polyurethane dispersion, to a suitable carrier;
e) drying the coating.