Polyurea-based fabric glue

Abstract

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.

Claims

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) ##STR00004## wherein X is an organic radical containing no Zerewitinoff-active hydrogen, R.sub.1 and R.sub.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) ##STR00005## wherein R.sub.3, R.sub.4, and R.sub.5 independently of one another are alkyl or heteroalkyl radicals having heteroatoms in the alkyl chain or at the end thereof, or R.sub.3 and R.sub.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.

Description

EXAMPLES

(1) PEG 600: Polyethylene glycol of mass 600

(2) The processing life means the time within which the polymer mixture can still be applied by means of a metering system with static mixer.

Example 1 (Aspartate A)

(3) Added slowly dropwise under a nitrogen atmosphere to 2 mol of diethyl maleate was 1 mol of 2-methyl-1,5-diaminopentane, so that the reaction temperature did not exceed 60° C. This was followed by heating at 60° C. until diethyl maleate was no longer detectable in the reaction mixture. The product was used without further purification.

Example 2 (Polyester A)

(4) Water was removed by distillation at 210-220° C. under atmospheric pressure over 12 hours from a stirred mixture consisting of 24.7 g of adipic acid and 281.4 g of PEG 600. Then 30 mg of tin(II) chloride were added to the mixture, and water was removed by distillation under reduced pressure for a further 24 hours, until the mixture had an acid number of less than 1.

Example 3 (Polyester B)

(5) Water was removed by distillation at 210-220° C. under atmospheric pressure over 12 hours from a stirred mixture consisting of 24.7 g of adipic acid in 152.3 g of PEG 600. Then 30 mg of tin(II) chloride were added to the mixture, and water was removed by distillation under reduced pressure for a further 24 hours, until the mixture had an acid number of less than 1.

(6) The polyesters used are dewatered by stirring at 80° C. and 0.13 mbar for one hour.

Example 4 (Prepolymer A)

(7) A 1 l four-neck flask was charged with 680 g of HDI and 1.08 g of benzoyl chloride. Over the course of 2 hours, at 80° C., 400 g of the dewatered polyester A were added and stirring was continued for an hour. Then the excess HDI was removed by thin-film distillation at 130° C. and 0.13 mbar. This gave the prepolymer with an NCO content of 5.83%. The residual monomer content was <0.03% of HDI.

Example 5 (Prepolymer B)

(8) A 1 l four-neck flask was charged with 240 g of HDI and 0.53 g of benzoyl chloride. Over the course of 2 hours, at 80° C., 287.3 g of the dewatered polyester B were added and stirring was continued for an hour. Then the excess HDI was removed by thin-film distillation at 130° C. and 0.13 mbar. This gave the prepolymer with an NCO content of 3.83%. The residual monomer content was <0.03% of HDI.

Example 6

(9) An amount of 2.6 g of aspartate A was added to 8 g of the prepolymer A, with different amounts of water and amine, and the processing life was measured.

(10) TABLE-US-00001 Triethanolamine [%] Water [%] Processing life / / 11 min 20 s / 0.02  5 min 20 s / 0.2   1 min 40 s  0.06 / 10 min 10 s 0.6 /  9 min 50 s 0.6 0.02  4 min 40 s 0.6 0.2   1 min 15 s

Example 7

(11) An amount of 1.71 g of aspartate A was added to 8 g of the prepolymer B, with different amounts of water and amine, and the processing life was measured.

(12) TABLE-US-00002 Triethanolamine [%] Water [%] Processing life / / 20 min / 0.02  8 min 30 s / 0.2   2 min 20 s  0.06 / 18 min 0.6 / 13 min 50 s 0.6 0.02  6 min 30 s 0.6 0.2   2 min

Example 8

(13) An amount of 1.08 g of aspartate A was added to 8 g of a trifunctional polyether polyol-HDI prepolymer prepared in the same way as for prepolymer A and having an NCO content of 2.37%, with different amounts of water and amine, and the processing life was measured.

(14) TABLE-US-00003 Triethanolamine [%] Water [%] Processing life / /  9 min 50 / 0.02  5 min 40 s / 0.2   1 min 40 s  0.06 /  6 min 50 s 0.6 /  5 min 50 s 0.6 0.02  4 min 0.6 0.2  50 s

(15) In all cases, no change was observed in the adhesive strength to muscle tissue.