Polyurea-based fabric glue
The present invention relates to a polyurea system, the use of such a polyurea system for sealing, linking, gluing, or covering of cellular tissue, and a dosing system having two chambers for a polyurea system such as this. The polyurea system comprises as components: A) an isocyanate-functioning prepolymer, which can be derived by reacting aliphatic isocyanates with polyoles, and B) an amino-functioning ester of aspartic acid. According to the invention, water and/or tertiary amine is added to the system, in order to increase the reacting speed of the prepolymer with the amino-functioning ester of aspartic acid while decreasing the setting time at the same time.
1. A method for sealing, connecting, bonding or covering cellular tissue comprising applying a tissue adhesive composition comprising a polyurea system comprising
A) isocyanate-functional prepolymers obtained by reacting
aliphatic isocyanates A1) with
polyols A2) comprising polyester polyols and/or polyester-polyether polyols and/or polyether polyols, which have a number-average molecular weight of ≧400 g/mol and an average OH functionality of 2 to 6, and 60% to 90% of ethylene oxide-based units, based on the amounts of alkylene oxide units that are present in total,
B) amino-functional aspartic esters of formula (I)
wherein
X is an organic radical containing no Zerewitinoff-active hydrogen,
R 1 and R 2
are identical or different organic radicals containing no Zerewitinoff-active hydrogen, and
n is an integer of at least 2,
and/or
optionally C) organic fillers and
optionally D) reaction products of the isocyanate-functional prepolymers of A) with aspartic esters B) and/or organic fillers C),
wherein said system comprises water and tertiary amine as E), and wherein the system when cured has no cytotoxicity in accordance with ISO 10993,
to a cellular tissue to be sealed, connected, bonded, or covered.
2. The method of claim 1 , wherein the polyurea system comprises tertiary amines of formula (II)
wherein
R 3 , R 4 , and R 5 independently of one another are alkyl or heteroalkyl radicals having heteroatoms in the alkyl chain or at the end thereof, or R 3 and R 4 , together with the nitrogen atom carrying them, may form an aliphatic, unsaturated or aromatic heterocycle, which may optionally contain further heteroatoms.
3. The method of claim 1 , wherein the tertiary amine is selected from the group consisting of triethanolamine, tetrakis(2-hydroxyethyl)ethylenediamine, N,N-dimethyl-2-(4-methylpiperazin-1-yl)ethanamine, 2-{[2-(dimethylamino)ethyl](methyl)amino}-ethanol, and 3,3′,3″-(1,3,5-triazinane-1,3,5-triyl)tris(N,N-dimethylpropan-1-amine).
4. The method of claim 1 , wherein said polyurea system contains 0.2% to 2.0% by weight of water and/or 0.1% to 1.0% by weight of tertiary amine.
5. The method of claim 1 , wherein X is an optionally branched or linear organic radical having 1 to 20 carbon atoms which optionally contains heteroatoms.
6. The method of claim 1 , wherein the polyols used for preparing component A) have a number-average molecular weight of 4000 to 8500 g/mol.
7. The method of claim 1 , wherein the organic fillers of component C) are hydroxyl-functional compounds.
8. The method of claim 7 , wherein the fillers of component C) have an average OH functionality of 1.5 to 3.