Temperature resistant moisture curable silicone compositions

Abstract

The invention relates to a curable composition, adhesive, sealant, and/or coating materials comprising said composition and methods of using said composition, wherein the curable composition comprises:

I. organyloxy group containing organopolysiloxanes comprising (A) organopolysiloxane(s) containing organyloxy groups and consisting of units of the formula (I)

##STR00001## and/or their partial hydrolysates, (B) organosilicon compound(s) of the formula (II)

##STR00002## (C) organosilicon compound(s) containing basic nitrogen, of the formula (III)

##STR00003## and/or their partial hydrolysates, and optionally (D) organosilicon compound(s) of the formula (IV)

##STR00004## and/or their partial hydrolysates, where R, R.sup.1, R.sup.2, a, b, c, R.sup.3, R.sup.4, d, R.sup.5, R.sup.6, e, R.sup.7, R.sup.8 and h are defined as stated in the specification,
II. a first pigment,
III. a second pigment,
IV. optionally surface treated silica,
V. surface treated calcium carbonate,
VI. optionally a Cerium (III) additive,
VII. optionally a tin catalyst.

Claims

1. A curable composition comprising, I. organyloxy group containing organopolysiloxanes comprising (A) organopolysiloxane(s) containing organyloxy groups and consisting of units of the formula (I) ##STR00012## where R are identical or different and represent monovalent, SiC-bonded, optionally substituted hydrocarbyl radicals that are free from aliphatic carbon-carbon multiple bonds, R.sup.1 are identical or different and denote monovalent, SiC-bonded, optionally substituted hydrocarbyl radicals having aliphatic carbon-carbon multiple bonds, R.sup.2 are identical or different and denote monovalent, optionally substituted hydrocarbyl radicals, optionally interrupted by oxygen atoms, a is 0, 1, 2 or 3, b is 0 or 1, and c is 0, 1, 2 or 3, with the proviso that in formula (I) the sum a+b+c3 and c is other than 0 in at least one unit, (B) organosilicon compound(s) of the formula (II) ##STR00013## where R.sup.3 are identical or different and denote monovalent, SiC-bonded, aliphatic hydrocarbyl radicals having 1 to 7 carbon atoms, that are optionally substituted by one or more of ether groups, ester groups, (poly)glycol radicals, triorganyloxysilyl groups, or aromatic radicals, R.sup.4 are identical or different and denote hydrogen or monovalent, optionally substituted hydrocarbyl radicals which are optionally interrupted by oxygen atoms, and d is 2, 3 or 4, and/or their partial hydrolysates, (C) organosilicon compound(s) containing basic nitrogen, of the formula (III) ##STR00014## where R.sup.5 are identical or different and denote monovalent, SiC-bonded radicals containing basic nitrogen, R.sup.6 are identical or different and denote hydrogen or monovalent, optionally substituted hydrocarbyl radicals which are optionally interrupted by oxygen atoms, e is 2 or 3, and/or their partial hydrolysates, and optionally (D) organosilicon compound(s) of the formula (IV) ##STR00015## where R.sup.7 are identical or different and denote monovalent, SiC-bonded, aliphatic hydrocarbyl radicals having at least 8 carbon atoms, optionally substituted by one or more of ether groups, ester groups, (poly)glycol radicals or triorganyloxysilyl groups, R.sup.8 are identical or different and denote hydrogen or monovalent, optionally substituted hydrocarbyl radicals which are optionally interrupted by oxygen atoms, h is 2 or 3, and/or their partial hydrolysates, II. a first pigment, III. a second pigment, IV. optionally surface treated silica, V. surface treated calcium carbonate, VI. optionally a Cerium (III) additive, VII. optionally a tin catalyst.

2. The curable composition according to claim 1, wherein organopolysiloxanes (A) are substantially linear, organyloxyterminated organopolysiloxanes of the formula (V) ##STR00016## where R, R.sup.1 and R.sup.2 are each identical or different, and have one of the definitions stated above, g is 30 to 5000, and f is 0, 1 or 2, with the proviso that in formula (V) f is other than 0 in at least one unit.

3. The curable composition according to claim 1, wherein at least one organopolysiloxane (A) is (MeO).sub.2MeSiO[SiMe.sub.2O].sub.200-2000SiMe(OMe).sub.2, (MeO).sub.2MeSiO[SiMe.sub.2O].sub.200-2000SiVi(OMe).sub.2, (MeO).sub.2ViSiO[SiMe.sub.2O].sub.200-2000SiVi(OMe).sub.2, (MeO).sub.2MeSiO[SiMe.sub.2O].sub.200-2000SiViMe(OMe), (MeO)ViMeSiO[SiMe.sub.2O].sub.200-2000SiViMe(OMe), or (MeO)ViMeSiO[SiMe.sub.2O].sub.200-2000SiVi(OMe).sub.2.

4. The curable composition according to claim 1, wherein organosilicon compound (D) has at least one radical R.sup.8 having at least two carbon atoms.

5. The curable composition according to claim 1, wherein at least one organosilicon compounds (D) is hexadecyltrimethoxysilane, hexadecyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, isooctyltrimethoxysilane or isooctyltriethoxysilane and/or their partial hydrolysates.

6. The curable composition according to claim 1, wherein having a weight ratio of component (B) to component (C) in a range from 2:1 to 1:2.

7. The curable composition according to claim 1, which comprises: (A) organopolysiloxanes consisting of units of the formula (I), (B) organosilicon compounds of the formula (II) having at least one methyl or ethyl radical R.sup.4 and/or their partial hydrolysates, (C) organosilicon compounds containing basic nitrogen and of the formula (III) and/or their partial hydrolysates, optionally (D) organosilicon compounds of the formula (IV) having at least one ethyl radical R.sup.8 and/or their partial hydrolysates, optionally (E) fillers, optionally (F) catalysts, optionally (G) stabilizers, optionally (H) additives, and optionally (J) plasticizers.

8. The curable composition according to claim 1, which comprises: (A) organopolysiloxanes of the formula (V) with vinyl radical R.sup.1, (B) organosilicon compounds of the formula (II) having at least one methyl or ethyl radical R.sup.4 and/or their partial hydrolysates, (C) organosilicon compounds containing basic nitrogen and of the formula (III) selected from N-(2-amino-ethyl)-3-aminopropyltrimethoxysilane and N-(2-ami-noethyl)-3-aminopropyltriethoxysilane and their partial hydrolysates, optionally (D) organosilicon compounds of the formula (IV) having an alkyl radical R.sup.7 having 8 to 16 carbon atoms and at least one ethyl radical R.sup.8 and/or their partial hydrolysates, optionally (E) fillers, optionally (F) catalysts, (G) stabilizers, optionally (H) additives and (J) plasticizers, with the proviso that the weight ratio of component (B) to component (C) is in the range from 2:1 to 1:2.

9. The curable composition according to claim 1, wherein the first pigment is diiron trioxide.

10. The curable composition according to claim 1, wherein the second pigment is carbon black.

11. The curable composition according to claim 1, additionally comprising an aminosilane.

12. The curable composition according to claim 1, wherein the R.sup.2, R.sup.4, R.sup.6 and/or R.sup.8 is a lactato group.

13. The curable composition according to claim 1, wherein (i) the amount of the organyloxy group containing organopolysiloxanes (I) is from 10 wt.-% to 90 wt.-%, based on the total weight of the composition; and/or (ii) the amount of the first pigment (II) is from 0.1 wt.-% to 50 wt.-%, based on the total weight of the curable composition; and/or (iii) the amount of the second pigment (III) is 0.1 wt.-% to about 25 wt.-%, based on the total weight of the curable composition; and/or (iv) the amount of the surface treated silica (IV) is 0 to 15 wt.-%, based on the total weight of the curable composition (v) the amount of the surface treated calcium carbonate (V) is 0.1 wt.-% to 80 wt.-%, based on the total weight of the curable composition; and/or, (vi) the amount of Cerium (VI) additive is 0 to 3 wt.-%, based on the total weight of the curable composition; and/or, (vii) the amount of the tin catalyst (VII) is 0 to 3 wt.-%, based on the total weight of the curable composition; and/or (viii) the amount of the aminosilane is 0 to 7 wt.-%, based on the total weight of the curable composition.

14. An adhesive, sealant, or coating material comprising the curable composition according to claim 1.

15. A method of adhering a substrate to itself or another substrate, sealing or coating a substrate comprising applying the curable composition according to claim 1 to the substrate(s) and curing said composition to create an adhesive bond, a sealant, or a coating on the substrate.

Description

EXAMPLES

[0231] Unless otherwise stated, the examples which follow are carried out at a pressure of the surrounding atmosphere, in other words approximately at 1000 hPa, and at room temperature, in other words at approximately 23 C., and/or at a temperature which comes about when the components are combined at room temperature without additional heating or cooling, and also at a relative atmospheric humidity of approximately 50%. Furthermore, all figures for parts or percentages, unless otherwise stated, are by weight.

[0232] The formulations were prepared as described in the Tables below and subjected to curing performance tests as follows: [0233] Tensile strength and elongation: The tensile strength and elongation at break were determined in accordance with DIN 53504. The samples were cured in a mold at room temperature over seven days. The specimen type S2 (Dog bone) was used and the speed of the pull head in the dynamometer was 200 mm/min. [0234] Determination of Skin-over time (SOT) A: Skin-over time (SOT) is defined as the time required for the material to form a non-tacky surface film. The determination of the skin over time is carried out according to DIN 50014 under standard climate conditions (23+/2 C., relative humidity 50+/5%). The temperature of the sealant must be 23+/2 C., with the sealant/adhesive stored for at least 24 h beforehand in the laboratory. The sealant/adhesive is applied to a sheet of paper and spread out with a putty knife to form a skin (thickness about 2 mm, width about 7 cm). The stopwatch is started immediately. At intervals, the surface is touched lightly with the fingertip and the finger is pulled away, with sufficient pressure on the surface that an impression remains on the surface when the skin formation time is reached. The skin-over time is reached when the sealing/adhesive compound no longer adheres to the fingertip. The skin-over time (SOT) is expressed in minutes. [0235] Determination of Skin-over time (SOT) B: Skin-over time (SOT) is defined as the time required for the material to form a non-tacky surface film. The determination of the skin over time is carried out according to DIN 50014 under standard climate conditions (23+/2 C., relative humidity 50+/5%). The temperature of the sealant must be 23+/2 C., with the sealant/adhesive stored for at least 24 h beforehand in the laboratory. The sealant/adhesive is applied to a sheet of paper and spread out with a putty knife to form a skin (thickness about 2 mm, width about 7 cm). The stopwatch is started immediately. At intervals, the surface is touched lightly with a folded piece of paper and pulled away, with sufficient pressure on the surface that an impression remains on the surface when the skin formation time is reached. The skin-over time is reached when the sealing/adhesive compound no longer adheres to the folded paper. The skin-over time (SOT) is expressed in minutes. [0236] Measurement of Shore A hardness: Shore A hardness was measured according to ISO 868. [0237] Density: The density was determined according to ISO 9073-1 (from 1989). [0238] Determination of the depth of cure (DOC): A strip of the material with a height of 10 mm (+/1 mm) and width of 20 mm (+/2 mm) was applied over a plastic foil (PP) using a Teflon spatula. After storing the sample for 24 hours at normal conditions (23+/2 C., relative humidity 50+/5%), a section of the strip was cut off and the thickness of the cured layer was measured with a caliper. The depth of cure after 24 hours is expressed in millimeters. [0239] Peel test: If possible and needed, substrate (test panel) is cleaned prior to application using a suitable solvent (e.g. isopropanol, acetone). A bead of the material with a height of 10 mm (+/1 mm) and width of 20 mm (+/2 mm) was applied over the substrate using a Teflon spatula/cartridge and cartridge gun. The sample was stored for 7 days at normal conditions (23+/2 C., relative humidity 50+/5%). The cured material was cut back for at least 15 mm with a shape blade and the bead pulled by hand. Failure mode was recorded as cf 85, cf 90 and cf 100, wherein cf XX refers to XX % of wetted surface shows cohesive break

TABLE-US-00001 TABLE 1 Comparative Comparative Comparative Example 1 Example 2 Example 3 Example 4 [%] [%] [%] [%] polydimethylsiloxane 72.500 72.500 72.500 50.360 with dimethoxysilyl- end groups.sup.1 polydimethylsiloxane 8.000 8.000 8.000 5.540 with dimethoxysilyl- end groups.sup.2v diiron trioxide 5.200 5.200 5.200 2.000 carbon black 6.200 6.200 6.200 4.000 surface-treated 30.000 calcium carbonate coated with stearic acid surface-treated 3.300 3.300 3.300 3.300 fumed silica methyl trimethoxy 3.000 3.000 3.000 3.000 silane 3-aminopropyl 0.500 0.500 0.500 trimethoxy silane N-(beta-aminoethyl)- 0.500 0.500 gamma-aminopropyl trimethoxy silane.sup.3 aminoalkyl modified 0.500 0.500 0.500 oligosiloxane.sup.4 Bis(trimethylsilyl) 0.300 0.300 0.300 0.300 amine cerium tris(2-ethyl 0.200 0.200 0.200 0.200 hexanoate) 12% dioctyltin 0.300 0.300 0.300 0.300 dineodecanoate .sup.1Polymer AL 60 commercially available from Wacker Chemie AG, Germany .sup.2Polymer AL 08 commercially available from Wacker Chemie AG, Germany .sup.3Silquest A-1120 commercially available from Momentive Performance Materials, Inc., USA .sup.4Dynasylan 1146 commercially available from Evonik Operations GmbH, Germany

TABLE-US-00002 TABLE 2 after curing 750 h @ 180 C. 1,500 h @ 180 C. 2,250 h @ 180 C. 3,000 h @ 180 C. Tensile Tensile Tensile Tensile Tensile Strength Elongation Strength Elongation Strength Elongation Strength Elongation Strength Elongation [MPa] [%] [MPa] [%] [MPa] [%] [MPa] [%] [MPa] [%] oxime silicone 1.2 220 1.75 300 1.55 283 1.7 280 1.5 283 paste.sup.5 Comparative 0.9 262 1.1 388 0.8 355 1.0 430 0.7 420 Example 1 Comparative 1.0 281 1.0 406 0.9 394 1.1 510 0.75 514 Example 2 Comparative 0.9 266 1.0 420 0.8 419 1.0 480 0.8 458 Example 3 Example 4 1.7 410 2.0 462 2.24 323 1.86 229 2.51 159 .sup.5Teroson SI 176 commercially available from Henkel AG & Co. KGaA, Germany

TABLE-US-00003 TABLE 3 oxime silicone Comparative Comparative Comparative Example unit paste.sup.5 Example 1 Example 2 Example 3 4 Skin time A [min] 63 120 120 120 n.d. Skin time B [min] 7 325 335 340 12 Shore A 1 d n.d. 23 16 19 23 Shore A 7 d n.d. 24 26 24 34 Shore A 38 27 26 28 38 14 d Density [g/cm.sup.3] 1.28 1.07 1.06 1.07 1.30 Cure speed [mm/24 h] 2.1 2.5 3 2.8 2.2

TABLE-US-00004 TABLE 4 oxime silicone paste.sup.5 Comparative Example 1 Comparative Example 2 Comparative Example 3 substrate A2/1.sup.6 A2/4.sup.7 A2/1.sup.6 A2/4.sup.7 A2/1.sup.6 A2/4.sup.7 A2/1.sup.6 A2/4.sup.7 glass cf 85 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 Anodized cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 aluminum Brass cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 stainless steel cf 90 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 glass fiber cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 reinforced epoxy PA 6.6 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 Aluminum cf 85 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 cf 100 Magnesium Silicon alloy AlMgSi1 .sup.61 week .sup.74 weeks