Process for the production of polyurethane polyureas containing side chains and of aqueous dispersions of these

A process for preparing aqueous polyurethane-polyurea dispersions comprising a sidechain-bearing polyurethane-polyurea polymer, the process comprising the steps of

• A) initially
• A1) reacting primary diamines, secondary diamines or a mixture thereof comprising a group which is incorporated as sidechain into the polyurethane-polyurea polymer, with
• A2) cyclic carbonates containing one hydroxyl group, wherein the molar ratio of Al) and A2) is determined such that an arithmetic ratio of total primary and/or secondary amine groups to cyclic carbonate groups in the range from 1.8 to 2.2 is obtained, and
• A3) the remaining primary and/or secondary amine groups are reacted with compounds bearing one functional group reacting with primary and/or secondary amines in an addition reaction, so that no isocyanate-reactive groups are formed, wherein the amount of substance of A3) is determined such that an arithmetic ratio of total primary and/or secondary amine groups arithmetically remaining after reaction of Al) and A2) to amine-reactive groups in A3) in the range from 0.8 to 1.2 is obtained,
• wherein the reaction with A3) can take place after, simultaneously with or before the reaction with A2),
• B) subsequently producing an NCO-containing polyurethane prepolymer by reacting
• B1) polyisocyanates with
• B2) polymeric polyols, polyamines or a mixture thereof having number average molecular weights of more than 400 to 8000 g/mol,
• B3) optionally low molecular weight compounds having number average molecular weights of 17-400 g/mol selected from the group consisting of monoalcohols, polyalcohols, monoamines, polyamines and amino alcohols,
• B4) optionally isocyanate-reactive ionically or potentially ionically hydrophilizing compounds, isocyanate-reactive nonionically hydrophilizing compounds or a mixture thereof, and
• B5) the reaction products from A),
• C) the prepolymer from B) being dispersed in water, and
• D) optionally reacting the still free NCO groups of the prepolymer with isocyanate-reactive monoamines, polyamines, hydrazine, hydrazides or a mixture thereof, wherein the amount of substance thereof is determined such that an arithmetic ratio of isocyanate-reactive NH groups to NCO groups in the range from 0 to 1.2 is obtained, wherein said reaction D) can be effected partly or else wholly before or during the dispersing step C), and
• wherein the Al) components are diamines of structural formula (2)
• wherein
• R3 is selected from the group consisting of partially and/or completely fluorinated hydrocarbons having 4 to 18 carbon atoms, colysiloxanes having molecular weights of 400 to 5000 g/mol, and mixtures thereof,
• R4 and R5 are each independently hydrogen or hydrocarbons having one to 18 carbon atoms, and
• p and q are each independently from 0 to 12.