Hydroxysilane and polymer containing silane groups

Abstract

Special hydroxysilanes, which can be obtained by reacting -(3,4-epoxycyclohexyl)alkyltrialkoxysilanes with secondary amines, and adducts of the hydroxysilanes in the form of polymers containing silane groups. The hydroxysilanes can be produced having high purity in a simple process and are very stable in storage after production. The polymers containing silane groups that can be obtained by means of the hydroxysilanes have advantageous properties. The polymers enable moisture-curing compositions, which contain no isocyanate groups and which are suitable as elastic adhesives and sealants.

Claims

1. A hydroxysilane of the formula (I) ##STR00007## where either R is a radical of the formula (II) and R is hydrogen or R is hydrogen and R is a radical of the formula (II); ##STR00008## R.sup.1 and R.sup.2 are either each individually an alkyl radical having 1 to 12 carbon atoms and optionally having heteroatoms in the form of ether oxygen, thioether sulfur or tertiary amine nitrogen, or together are an alkylene radical having 2 to 12 carbon atoms and optionally having heteroatoms in the form of ether oxygen, thioether sulfur or tertiary amine nitrogen; R.sup.3 is a linear or branched alkylene or cycloalkylene radical having 1 to 20 carbon atoms, optionally having aromatic moieties, and optionally having one or more heteroatoms; R.sup.4 is an alkyl group having 1 to 8 carbon atoms; R.sup.5 is an alkyl group having 1 to 10 carbon atoms and optionally having one or more ether oxygen heteroatoms; and x is 0 or 1 or 2.

2. A hydroxysilane as claimed in claim 1, wherein R.sup.1 and R.sup.2 are either individually 2-methoxyethyl, 2-ethoxyethyl, 3-methoxypropyl, 3-ethoxypropyl, 2-(2-methoxyethoxy)ethyl, 2-octyloxyethyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, 2-ethylhexyl or N,N-dimethylaminopropyl, or together with inclusion of the nitrogen atom are an optionally substituted pyrrolidine, piperidine, hexamethyleneimine, morpholine, thiomorpholine or 4-methylpiperazine ring.

3. A hydroxysilane as claimed in claim 1, wherein R.sup.3 is an ethylene radical.

4. A hydroxysilane as claimed in claim 1, wherein R.sup.5 is a methyl group or an ethyl group.

5. A hydroxysilane as claimed in claim 1, wherein x is 1 or 0.

6. A process for preparing a hydroxysilane as claimed in claim 1, which comprises reacting at least one epoxysilane of the formula (III) with at least one amine of the formula (IV) ##STR00009##

7. An adduct obtained from the reaction of a hydroxysilane as claimed in claim 1 with at least one compound containing at least one reactive group, selected from the group consisting of isocyanate, epoxide, acryloyl, methacryloyl, anhydride, carboxylic acid, ester, carbonate and cyclocarbonate groups.

8. The adduct as claimed in claim 7, wherein it is a polymer which has end groups of the formula (VI) and is free of isocyanate groups ##STR00010##

9. The adduct as claimed in claim 8, wherein the polymer has a molecular weight in the range from 1000 to 30000 g/mol.

10. The adduct as claimed in claim 8, wherein the polymer has a majority of polyoxyalkylene units.

11. The adduct as claimed in claim 8, wherein a majority of the end groups of the formula (VI) are bonded to cycloaliphatic radicals.

12. The adduct as claimed in claim 8, wherein the polymer has 1 to 4 end groups of the formula (VI).

Description

EXAMPLES

(1) Detailed hereinafter are working examples which are intended to illustrate the invention described in detail. It will be appreciated that the invention is not restricted to these described working examples.

(2) Standard climatic conditions are understood to mean a temperature of 231 C. and a relative air humidity of 505%. SCC stands for standard climatic conditions.

(3) 1. Preparation of Hydroxysilanes

Hydroxysilane HS-1: 2-morpholino-4(5)-(2-trimethoxysilylethyl)cyclohexan-1-ol

(4) In a round-bottom flask, 32.85 g (133.33 mmol) of -(3,4-epoxycyclohexyl)-ethyltrimethoxysilane (Silquest A-186 from Momentive), 15.34 g (176.08 mmol) of anhydrous morpholine and 0.10 g of lanthanum(III) triflate were stirred at 110 C. under a nitrogen atmosphere over the course of 2 h until no further reaction progress was found by means of gas chromatography. The crude product was aftertreated at 80 C. and about 1 mbar over the course of 30 minutes. A liquid product having a theoretical OH equivalent weight of 333.5 g was obtained.

(5) After the preparation, the product had a purity of 98% to 99% by weight (determined by means of gas chromatography). After storage with exclusion of moisture at room temperature for 3 months, the purity was unchanged.

Hydroxysilane HS-2: 2-Pyrrolidino-4(5)-(2-trimethoxysilylethyl)cyclohexan-1-ol

(6) As described for the hydroxysilane HS-1, 32.85 of Silquest A-186, 12.54 g of pyrrolidine and 0.10 g of lanthanum(III) triflate were converted. A liquid product having a theoretical OH equivalent weight of 317.5 g was obtained, which had not undergone any noticeable change after a storage time of 3 months at room temperature.

Hydroxysilane HS-3: 2-dibutylamino-4(5)-(2-trimethoxysilylethyl)cyclohexan-1-ol

(7) As described for the hydroxysilane HS-1, 32.85 g of Silquest A-186, 22.76 g of dibutylamine and 0.10 g of lanthanum(III) triflate were converted. A liquid product having a theoretical OH equivalent weight of 375.6 g was obtained, which had not undergone any noticeable change after a storage time of 3 months at room temperature.

Hydroxysilane HS-4: 2-morpholino-4(5)-(2-triethoxysilylethyl)cyclohexan-1-ol

(8) In a round-bottom flask, 38.46 g (133.33 mmol) of -(3,4-epoxycyclohexyl)-ethyltriethoxysilane (CoatOSil 1770 from Momentive), 15.34 g (176.08 mmol) of anhydrous morpholine and 0.10 g of lanthanum(III) triflate were stirred under a nitrogen atmosphere at 110 C. over the course of 2 h until no further reaction progress was found by means of gas chromatography. The crude product was aftertreated at 80 C. and about 1 mbar over the course of 30 minutes. A liquid product having a theoretical OH equivalent weight of 375.6 g was obtained. After the preparation, the product had a purity of 97% to 98% by weight (determined by means of gas chromatography). After storage with exclusion of moisture at room temperature for 3 months, the purity was unchanged.

Hydroxysilane HS-5: 2-pyrrolidino-4(5)-(2-triethoxysilylethyl)cyclohexan-1-ol

(9) As described for the hydroxysilane HS-4, 38.46 g of CoatOSil 1770, 12.54 g of pyrrolidine and 0.10 g of lanthanum(III) triflate were converted. A liquid product having a theoretical OH equivalent weight of 359.6 g was obtained, which had not undergone any noticeable change after a storage time of 3 months at room temperature.

Hydroxysilane HS-6: 2-(4-methylpiperazino)-4(5)-(2-triethoxysilylethyl)-cyclohexan-1-ol

(10) As described for the hydroxysilane HS-4, 38.46 g of CoatOSil 1770, 17.64 g of 4-methylpiperazine and 0.10 g of lanthanum(III) triflate were converted. A liquid product having a theoretical OH equivalent weight of 388.6 g was obtained, which had not undergone any noticeable change after a storage time of 3 months at room temperature.

Hydroxysilane HS-7: 2-dibutylamino-4(5)-(2-triethoxysilylethyl)cyclohexan-1-ol

(11) As described for the hydroxysilane HS-4, 38.46 g of CoatOSil 1770, 22.76 g of dibutylamine and 0.10 g of lanthanum(III) triflate were converted. A liquid product having a theoretical OH equivalent weight of 417.7 g was obtained, which had not undergone any noticeable change after a storage time of 3 months at room temperature.

Hydroxysilane HS-R1: 1-Morpholino-3-(3-trimethoxysilylpropoxy)propan-2-ol

(12) In a round-bottom flask, 28.36 g (120 mmol) of 3-glycidoxypropyltrimethoxysilane (Dynasylan GLYMO from Evonik Degussa), 12.55 g (144.1 mmol) of anhydrous morpholine and 7.00 g of anhydrous methanol were stirred under a nitrogen atmosphere and under reflux at 80 C. over the course of 5 h until no further reaction progress was found by means of gas chromatography. The crude product was aftertreated at 80 C. and about 1 mbar over the course of 30 minutes. A liquid product having a theoretical OH equivalent weight of 323.5 g was obtained.

(13) The reaction product had a purity of 76% by weight after the preparation and a purity of 52% by weight after storage with exclusion of moisture at room temperature for 1 month (determined by means of gas chromatography).

Hydroxysilane HS-R2: 1-morpholino-3-(3-triethoxysilylpropoxy)propan-2-ol

(14) As described for the hydroxysilane HS-R1, 33.41 g (120 mmol) of 3-glycidoxy-propyltriethoxysilane (Dynasylan GLYEO from Evonik Degussa), 12.55 g of anhydrous morpholine and 7.00 g of anhydrous ethanol were converted. A liquid product having a theoretical OH equivalent weight of 365.5 g was obtained.

(15) The reaction product had a purity of 94% by weight after the preparation and a purity of 83% by weight after storage with exclusion of moisture at room temperature for 1 month (determined by means of gas chromatography).

(16) The hydroxysilanes HS-1 to HS-7 are inventive hydroxysilanes of the formula (I); the hydroxysilanes HS-R1 and HS-R2 are noninventive hydroxysilanes for comparative purposes.

(17) A comparison of the purity of the hydroxysilanes prepared and stored shows that the inventive hydroxysilanes HS-1 (trimethoxysilane) and HS-4 (triethoxysilane) had a very high purity and excellent storage stability, while the comparative hydroxysilane HS-R1 (trimethoxysilane) was neither preparable in satisfactory purity nor storage-stable, and the comparative hydroxysilane HS-R2 (triethoxysilane) did have satisfactory purity after preparation but was not storage-stable.

(18) 2. Preparation of Polymers Containing Silane Groups

(19) Polymers SP-1 to SP-7

(20) For each polymer, 100 parts by weight (PW) of polymer 1 were mixed with the hydroxysilane specified in table 1 in the amount specified (OH/NCO=1.10). This mixture was stirred at 90 C. under a nitrogen atmosphere until no isocyanate groups were detectable any longer by means of IR spectroscopy (about 2 hours). Subsequently, the reaction mixture was cooled and kept with exclusion of moisture.

(21) The viscosity was determined the day after the preparation in each case in a thermostated Rheotec RC30 cone-plate viscometer (cone diameter 50 mm, cone angle 1, cone tip-plate distance 0.05 mm, shear rate 10 s.sup.1) at a temperature of 20 C.

(22) The properties of the polymers containing silane groups obtained are reported in table 1.

(23) The polymers SP-1 to SP-7 are inventive polymers having end groups of the formula (VI).

(24) Polymer 1 was prepared by mixing 720 g of Acclaim 12200 polyol (Bayer Material Science; low monool polyoxypropylene diol; OH number 11.0 mg KOH/g; water content of about 0.02% by weight), 34.5 g of isophorone diisocyanate (Vestanat IPDI, Evonik Degussa), 80.0 g of diisodecyl phthalate and 0.2 g of dibutyltin dilaurate under a nitrogen atmosphere, heated to 90 C. with constant stirring and left at this temperature until the content of free isocyanate groups determined by titrimetric means reached a value of 0.73% by weight. The product was cooled to room temperature and kept with exclusion of moisture.

(25) TABLE-US-00001 TABLE 1 Composition and properties of the polymers SP-1 to SP-7 containing silane groups. Polymer SP-1 SP-2 SP-3 SP-4 SP-5 SP-6 SP-7 Polymer 1 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Hydroxysilane HS-1, HS-2, HS-3, HS-4, HS-5, HS-6, HS-7, 6.38 6.07 7.18 7.18 6.88 7.43 7.99 Viscosity [Pa .Math. s] 80 136 118 66 130 83 138
3. Production of Moisture-Curing Compositions
Compositions Z-1 to Z-7

(26) For each composition, the ingredients specified in table 2 were mixed in the amounts specified (in parts by weight) by means of a centrifugal mixer (SpeedMixer DAC 150, FlackTek Inc.) with exclusion of moisture and kept. Each composition was tested as follows:

(27) To determine the skinning time, a few grams of the composition were applied to cardboard in a layer thickness of about 2 mm and, under standard climatic conditions, the time until, when the surface of the composition was tapped gently by means of an LDPE pipette, there were no remaining residues on the pipette for the first time was determined.

(28) To determine the mechanical properties, the composition was cast on a PTFE-coated film to give a film of thickness 2 mm, which was stored under standard climatic conditions for 2 weeks, some dumbbells having a length of 75 mm with a bar length of 30 mm and a bar width of 4 mm were punched out of the film and these were tested in accordance with DIN EN 53504 at a pulling speed of 200 mm/min for tensile strength (breaking force), elongation at break and modulus of elasticity (modulus of elasticity at 0.5%-50% elongation). Shore A hardness was determined in accordance with DIN 53505 on test specimens which had been cured under standard climatic conditions for 14 days.

(29) These results are appended with SCC:.

(30) As a measure of thermal stability, some dumbbells and the Shore A test specimens after the 2 weeks under standard climatic conditions were additionally stored in an air circulation oven at 90 C. for 1 week and then tested in the same way for tensile strength, elongation at break and modulus of elasticity, or for Shore A hardness. These results are appended with 90 C.:. The results are reported in table 2.

(31) TABLE-US-00002 TABLE 2 Composition and properties of the compositions Z-1 to Z-7. Composition Z-1 Z-2 Z-3 Z-4 Z-5 Z-6 Z-7 Polymer SP-1, SP-2, SP-3, SP-4, SP-5, SP-6 SP-7, 82.5 82.5 82.5 82.5 82.5 82.5 82.5 Silquest A-1120 .sup.1 3.8 3.8 3.8 Geniosil GF-94 .sup.2 3.2 3.2 3.2 3.2 Silquest A-171 .sup.3 0.3 0.3 0.3 Dynasilan VTEO .sup.4 0.3 0.3 0.3 0.3 DBTDL (10%) .sup.5 0.4 0.4 0.4 DBTDL (50%) .sup.6 1.0 1.0 1.0 1.0 Diisodecyl phthalate 13.0 13.0 13.0 13.0 13.0 13.0 13.0 Skinning time [min] 75 20 30 420 160 210 200 SCC: Shore A 33 22 24 34 31 24 22 Tensile strength [MPa] 0.58 0.37 0.42 0.35 0.55 0.53 0.43 Elongation at break [%] 102 103 113 92 90 95 100 Modulus of elasticity 0.65 0.34 0.38 0.24 0.62 0.57 0.42 [MPa] 90 C.: Shore A 36 21 24 33 33 32 28 Tensile strength [MPa] 0.60 0.36 0.41 0.55 0.52 0.47 0.36 Elongation at break [%] 91 102 112 83 81 80 66 Modulus of elasticity 0.66 0.32 0.36 0.68 0.62 0.57 0.47 [MPa] .sup.1 N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane from Momentive .sup.2 N-(2-Aminoethyl)-3-aminopropyltriethoxysilane from Wacker .sup.3 Vinyltrimethoxysilane from Momentive .sup.4 Vinyltriethoxysilane from Evonik .sup.5 Dibutyltin dilaurate 10% by weight in diisodecyl phthalate .sup.6 Dibutyltin dilaurate 50% by weight in diisodecyl phthalate
Compositions Z-8 to Z-14

(32) For each composition, the ingredients specified in table 3 were processed in the amounts specified (in parts by weight) in a vacuum mixer at 50 C. with exclusion of moisture over the course of 30 minutes to give a homogeneous paste and kept. Each composition was tested as follows:

(33) skinning time, tensile strength, elongation at break, moduli of elasticity and Shore A hardness were determined as described for composition Z-1. For the heated storage, however, the dumbbells, after the 2 weeks under standard climatic conditions, were stored at 100 C. for 4 weeks. These results are appended with 100 C.:.

(34) The results are reported in table 3.

(35) The thixotropic paste was produced by initially charging a vacuum mixer with 300 g of diisodecyl phthalate (Palatinol Z, BASF) and 48 g of 4,4-methylene-diphenyl diisocyanate (Desmodur 44 MC L, Bayer), gently heating them and then gradually adding 27 g of monobutylamine dropwise while stirring vigorously. Stirring of the paste formed was continued under reduced pressure while cooling for one hour.

(36) TABLE-US-00003 TABLE 3 Composition and properties of the compositions Z-8 to Z-14. Composition Z-8 Z-9 Z-10 Z-11 Z-12 Z-13 Z-14 Polymer SP-1, SP-2, SP-3, SP-4, SP-5, SP-6 SP-7, 15.00 15.00 15.00 15.00 15.00 15.00 15.00 Diisodecyl phthalate 20.00 20.00 20.00 20.00 20.00 20.00 20.00 Thixotropic paste 2.00 2.00 2.00 2.00 2.00 2.00 2.00 Silquest A-171 .sup.1 1.00 1.00 1.00 Dynasilan VTEO .sup.2 1.00 1.00 1.00 1.00 Socal U 1 S2 .sup.3 10.00 10.00 10.00 10.00 10.00 10.00 10.00 Omyacarb 5 GU .sup.4 50.00 50.00 50.00 50.00 50.00 50.00 50.00 Dynasylan AMMO .sup.5 0.75 0.75 0.75 Dynasylan AMEO .sup.6 0.75 0.75 0.75 0.75 DBTDL (10%) .sup.7 1.00 1.00 1.00 Polycat DBU .sup.8 0.20 0.20 0.20 0.20 Tyzor IBAY .sup.9 1.00 1.00 1.00 1.00 Skinning time [min] 25 10 5 270 185 55 80 SCC: Shore A 41 32 27 32 29 31 23 Tensile strength [MPa] 1.50 1.08 1.06 1.07 0.92 0.90 0.84 Elongation at break [%] 136 132 178 527 529 555 676 Modulus of elasticity 1.20 0.77 0.65 0.75 0.61 0.58 0.38 [MPa] 100 C.: Shore A 27 18 11 34 32 37 29 Tensile strength [MPa] 0.87 0.55 0.41 0.88 0.81 1.02 0.80 Elongation at break [%] 85 83 79 100 85 121 134 Modulus of elasticity 0.94 0.64 0.48 1.01 1.07 1.11 0.79 [MPa] .sup.1 Vinyltrimethoxysilane from Momentive .sup.2 Vinyltriethoxysilane from Evonik .sup.3 Precipitated coated calcium carbonate from Solvay .sup.4 Calcium carbonate from Omya .sup.5 3-Aminopropyltrimethoxysilane from Evonik .sup.6 3-Aminopropyltriethoxysilane from Evonik .sup.7 Dibutyilin dilaurate 10% by weight in diisodecyl phthalate .sup.8 1,8-Diazabicyclo[5.4.0]undec-7-ene from Air Products .sup.9 Titanium(IV) bis(ethylacetoacetato) complex from Du Pont/Dorf Ketal