Composition for Silicone Rubber Masses

Abstract

A composition containing a curing agent for silicone rubber masses and an organosilane, in particular a heterocyclic organosilane, as well as sealing agents, adhesives or coating agents containing this composition, the use of this composition as a sealing agent, adhesive or coating agent and the use of an organosilane according to the invention, in particular a heterocyclic organosilane as a water scavenger, alcohol scavenger and/or hydroxide ion scavenger and, after activation, as an adhesion promoter in silicone rubber masses is presented and described.

Claims

1. Composition comprising a. a curing agent for silicone rubber masses comprising a compound having the general structural formula R.sup.1.sub.mSi(R).sub.4-m, wherein each R.sup.1 independently represents an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted C4 to C14 aryl group, m is an integer from 0 to 2, each R is independently selected from the group consisting of a hydroxycarboxylic acid ester residue having the general structural formula (I): ##STR00019## wherein each R.sup.2 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, or a C4 to C14 aryl group, each R.sup.3 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, or a C4 to C14 aryl group, R.sup.4 represents an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group, a C5 to C15 aralkyl group or a C4 to C14 aryl group, R.sup.5 is C or an optionally substituted saturated or partially unsaturated cyclic ring system having 4 to 14 C atoms or an optionally substituted aromatic group having 4 to 14 C atoms, and n is an integer from 0 to 10, a hydroxycarboxylic acid amide residue of the general structural formula (II): ##STR00020## wherein each R.sup.6 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, or a C4 to C14 aryl group, each R.sup.7 or R.sup.8 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group or a C4 to C14 aryl group, —O—C(O)—R.sup.9, wherein R.sup.9 means H, an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group or a C4 to C14 aryl group, and —O—N═CR.sup.10R.sup.11, wherein R.sup.10 and R.sup.11 independently mean H, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group or a C4 to C14 aryl group, and b. at least one organosilane as water scavenger, alcohol scavenger and/or hydroxide ion scavenger and c. optionally at least one organopolysiloxane.

2. Composition according to claim 1 characterized in that a heterocyclic organosilane is contained, wherein at least one silicon atom and at least one heteroatom are directly linked to one another and the heteroatom is selected from the group consisting of N, P, S or O.

3. Composition according to claim 2 characterized in that one or more heterocyclic organosilanes are selected from the group of the general structural formulae (III), (IIIa), (IV), (IVa), (V), (Va) or mixtures thereof: ##STR00021## wherein a is 0, 1 or 2; x means 0 to 100; y means 1 to 1000; n means 0 to 6 each R.sup.a, R.sup.b, R.sup.c, R.sup.d, R.sup.e, R.sup.f or R.sup.g is independently H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group; each R.sup.A and/or R.sup.B and/or (R.sup.C).sub.n taken together form a 4- to 10-membered ring.

4. Composition according to claim 1, characterized in that one or more organosilanes are selected from the group consisting of iminosilanes of the general structural formula (VII), silanoaminosilanes of the general structural formula (VIII), non-cyclic organosilanes of the general structural formula (IX), amino-protecting group-containing organosilanes (IXa) to (IXe) derived from the general structural formula (IX) or mixtures thereof: ##STR00022## wherein R.sup.h is C or Si; each R.sup.i, R.sup.j independently mean H, —C(O)R.sup.t, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted C4 to C14 aryl group each R.sup.k, R.sup.l, R.sup.m independently mean H, —C(O)R.sup.t, an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted C4 to C14 aryl group each R.sup.n, R.sup.o, R.sup.p, R.sup.q, R.sup.r, R.sup.s independently mean H, —O—R.sup.t, —C(O)—R.sup.t, —COOR.sup.t, an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted C4 to C14 aryl group each R.sup.t, R.sup.u independently mean H, —OR.sup.i, —C(O)R.sup.i, —C(O)CF.sub.3, —COOR.sup.i, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group, an optionally substituted C4 to C14 aryl group, or a protecting group in particular a tert-butoxycarbonyl group, a fluorenylmethoxycarbonyl group, a benzyloxycarbonyl group, an allyloxycarbonyl group, an optionally substituted isoindole-1,3-dione group or a 3-methyl-benzenesulfone group, and z is an integer from 1 to 30.

5. Composition at least comprising a mixture obtainable by mixing at least one curing agent according to claim 1a with at least one organosilane 4b and/or a heterocyclic organosilane according to claim 3b.

6. Composition according to claim 1, characterized in that the organosilane is contained at a maximum of 3 wt.-% based on the total weight of the composition.

7. Composition according to claim 2, characterized in that the heterocyclic organosilane is a 4- to 10-membered heterocycle.

8. Composition according to claim 2 characterized in that the heterocyclic organosilane is a 5- to 6-membered heterocycle.

9. Composition according to claim 6, characterized in that the heterocycle contains at least one N.

10. Composition according to claim 1, characterized in that the silicon atom carries at least one OR.sup.d residue and each R.sup.d independently carries H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, represents an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group.

11. Composition according to claim 2, characterized in that the heterocyclic organosilane has at least one of the following structural formulae: ##STR00023## wherein a is 0, 1 or 2; x means 0 to 100; y means 1 to 1000; n means 0 to 6 each R.sup.a, R.sup.b, R.sup.c, R.sup.d, or R.sup.g is independently H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group; R.sup.A and/or R.sup.B and/or (R.sup.C).sub.n taken together form a 4- to 10-membered ring.

12. Composition comprising, a. a curing agent for silicone rubber masses comprising a compound having the general structural formula R.sup.1.sub.mSi(R).sub.4-m, wherein each R.sup.1 independently means an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted C4 to C14 aryl group, m is an integer from 0 to 2, each R is independently selected from the group consisting of —O—N═CR.sup.10R.sup.11, wherein R.sup.10 and R.sup.11 independently means H, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group or a C4 to C14 aryl group, and b. at least one heterocyclic organosilane having at least one of the following structural formulae: ##STR00024## wherein a is 0, 1 or 2; x means 0 to 100; y means 1 to 1000; n means 0 to 6; each R.sup.a, R.sup.b, R.sup.c, R.sup.d or R.sup.g is independently H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group; each R.sup.A and/or R.sup.B and/or (R.sup.C).sub.n taken together form a 4- to 10-membered ring.

13. Composition according to claim 12, characterized in that it contains at least one organopolysiloxane.

14. Composition according to claim 12, characterized in that it contains a) 30 to 70 wt.-% α, ω-dihydroxydialkyl organopolysiloxane, b) 1 to 10 wt.-% of curing agent and c) 0.1 to 10 wt.-% organosilane.

15. A process for preparing a composition comprising the following steps: (i) Mixing an organopolysiloxane with a crosslinker or a crosslinker mixture according to claim 1 under vacuum; (ii) Mixing in an organosilane and a catalyst under vacuum, wherein the catalyst is selected from the group consisting of tin carboxylates, titanium, zirconium or aluminium compounds.

16. Use of an organosilane of claim 1 as a water scavenger, alcohol scavenger and/or hydroxide ion scavenger.

17. Use of a composition of claim 1 for the manufacture of a silicone rubber composition.

18. Use of a reaction product of at least one organosilane with water, as adhesion promoter.

19. Use of a composition of claim 1 as a sealant, adhesive, potting compound or coating agent.

20. Use of an organosilane claim 1 as a stabilizer, characterized in that it carries a trialkylsilyl group on at least one heteroatom.

Description

EXAMPLES

[0207] Adhesion Promoter Synthesis

[0208] Some heterocyclic organosilanes are commercially available compounds such as N-n-butyl-aza-2,2-dimethoxysilacyclopentane ((BDC), CAS No. 618914-44-6), 2,2-diethoxy-1-(3-triethoxysilylpropyl)aza-2-silacyclopentane ((TESPDC), CAS No. 1184179-50-7) or 2,2-diethoxy-1-(trimethylsilyl)aza-2-silacyclopentane ((TMS)DEC), CAS No. 21297-72-3).

[0209] However, heterocyclic organosilanes are preferably produced synthetically from the non-cyclic precursor molecules. In principle, the synthesis is already known in the prior art and is exemplified by the preparation of a sila-aza-cyclopentane (BDC)

Example 1

Synthesis of (BDC)

[0210] In a 500 mL triple-necked flask with paddle stirrer and reflux condenser, 100.40 g (105.70 mL, 0.43 mol) butylaminopropyltrimethoxysilane (BAPTMS) with 2 g ammonium sulfate (1.13 mL, 0.015 mol) are added under nitrogen atmosphere and slowly heated to boiling point (100° C.) while stirring and kept at this temperature for 8 h. Removal of the volatile reaction components at 100° C. and 25 mbar yields 52.5 g (0.26 mol, 60%) of the product N-n-butyl-aza-2,2-dimethoxysilacyclopentane (BDC) as pale yellow liquid.

[0211] Sealant Formulations

[0212] Further sealant formulations were produced and tested.

[0213] In the case of the examples described below, all parameters were determined using the test procedures described below. All sealants described below were transparent and colorless and exhibited a pleasant odor as well as proper stability and notch resistance after 24 hours. Furthermore, the following sealants passed all three test specimens according to DIN EN ISO 8340 climatic method A on glass at an elongation of 100% of the initial length, wherein the elongation was maintained for 24 h.

[0214] The product properties skin formation time, tack-free time, through-curing and elongation at break of the silicone rubber masses (sealant formulations) were determined after application of the sealants using the test methods described below. Unless otherwise stated, the measurements were performed at 23° C. and 50% humidity.

[0215] The skin formation time indicates the time at which a complete layer of solidified material (skin) was observed on the surface of a sample strand after application of the sealant. The tack-free time indicates the time at which the surface of a sample strand no longer exhibits tack. To determine the complete curing, the sealant is applied to a glass plate at a height of 9 mm and the time taken to cure through to the glass plate is measured. The elongation at break was determined according to DIN EN ISO 8339:2005-09.

Example 2

Lactate Crosslinker Mixture with 2,2-dimethoxy-1-(n-butyl)aza-2-silacyclopentane (BDC)

[0216]

TABLE-US-00001 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.1 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 32.9 3 Crosslinker 1: Vinyl-tris(ethyllactato)silane 2.5 4 Crosslinker 2: Methyl-tris(ethyllactato)silane 2.5 5 Aminopropyltriethoxysilane (AMEO) 0.2 6 Pyrogenic silica, untreated 8.5 BET surface 130-150 m2/g 7 Catalyst 1:1 (w/w) Mixture of dialkyl zinc 0.1 oxide and tetraalkoxysilane 8 Adhesion promoter: 2,2-dimethoxy-1-(n- 1.2 butyl)aza-2-silacyclopentane (BDC)

[0217] α,ω-dihydroxy-dimethyl-polysiloxane 80,000 cSt, PDMS 100 cSt, vinyl-tris(ethyllactato)silane and methyl-tris(ethyllactato)silane were mixed under vacuum. AMEO was then mixed in as a thixotropic agent. The silica was then dispersed and stirred under vacuum until the mass was smooth. Finally, the catalyst as a 1:1 (w/w) mixture of dialkyl zinc oxide and tetraalkoxysilane and the adhesion promoter 2,2-dimethoxy-1-(n-butyl)aza-2-silacyclopentane (BOO) were mixed in under vacuum.

[0218] The product was transparent and colorless. It was characterized by a skin formation time of 6 minutes and a tack-free time of 100 minutes. The composition had good adhesion on all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, wood varnished, wood glazed, polyamide, polystyrene, Metzoplast and Al/Mg alloy and had a pleasant odor. The determined Shore A cureness was 27. Even after 6 weeks storage at 50° C., the sealant was stable after curing (Shore A:18) and showed only a slightly yellowish coloration, wherein the resulting sealant was colorless again after exposure to light. The extrusion when using a 2 mm diameter die at 5 bar and 30 seconds was 24.0 g. Furthermore, the sealant showed excellent properties:

TABLE-US-00002 Property Sealant Early resilience 105 min Through curing on glass (9  4 d mm) DIN EN ISO 8339 0.26 Elongation stress value at 100% elongation (N/mm2) DIN EN ISO 8339 0.42 Secant modulus at elongation at break (N/mm2) DIN EN ISO 8339  285% Elongation at break DIN EN ISO 7389  93% Average resilience DIN 53504 0.98 Tear resistance (N/mm2) DIN 53504 1050% Elongation at break

Example 3

Lactate Crosslinker Mixture with 2,2-diethoxy-1-(trimethylsilyl)aza-2-silacyclopentane (TMS-DEC)

[0219]

TABLE-US-00003 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.1 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 32.4 3 Crosslinker 1: Vinyl-tris(ethyllactato)silane 0.8 4 Crosslinker 2: Methy-ltris(ethyllactato) 3.2 silane 5 Aminopropyltriethoxysilane (AMEO) 0.2 6 Pyrogenic silica, hydrophobic 10.0 BET surface 130-150 m2/g 7 Catalyst 1:1 (w/w) Mixture of dialkyl zinc 0.1 oxide and tetraalkoxysilane 8 Adhesion promoter: 2,2-diethoxy-1- 1.2 (trimethylsilyl)aza-2-silacyclopentane (TMS-DEC)

[0220] Polymer 80,000 cSt, PDMS 100 cSt and the crosslinker mixture of vinyl-tris(ethyllactato)silane and methyl-tris(ethyllactato)silane were mixed under vacuum. The thixotropic agent AMEO was then added under vacuum. The silica was then dispersed and stirred under vacuum until the mass was smooth. The catalyst was then mixed in as a 1:1 (w/w) mixture of dialkyl zinc oxide and tetraalkoxysilane and the adhesion promoter 2,2-diethoxy-1-(trimethylsilyl)aza-2-silacyclopentane (TMS-DEC) under vacuum.

[0221] The product was transparent and colorless. It was characterized by a skin formation time of 17 minutes and a tack-free time of 33 minutes. The resulting sealant had good adhesion to all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, wood varnished, wood glazed, polyamide, Al/Mg alloy, polystyrene and Metzoplast and had a pleasant odor.

[0222] The determined Shore A cureness was 22. Even after 8 weeks storage at 60° C., the sealant was stable (Shore A:16) and only showed a slightly yellowish coloration. Extrusion using a 2 mm diameter die at 5 bar and 30 seconds was 31.0 g, and the sealant was transparent and colorless again after exposure to light. The sealant was also characterized by the following excellent properties:

TABLE-US-00004 Property Sealant Early resilience 105 min Through curing on glass 6 d (9 mm) DIN EN ISO 8339 0.24 Elongation stress value at 100% elongation (N/mm2) DIN EN ISO 8339 0.45 Secant modulus at elongation at break (N/mm2) DIN EN ISO 8339 470% Elongation at break DIN EN ISO 7389  93% Average resilience DIN 53504 0.61 Tear resistance (N/mm2) DIN 53504 830% Elongation at break

Comparison of the Storage Stability when Using Adhesion Promoters According to the Invention (Examples 4 and 5) with Conventional Adhesion Promoters (Comparative Example)

[0223] In the case of the sealant formulations from the following examples 4 and 5 and the comparison example, silicone rubber masses are each produced with the following formulation:

TABLE-US-00005 521 g Alpha,omega-dihydroxyl terminated polydimethylsiloxane with viscosity 80,000 cSt 324 g Polydimethylsiloxane with viscosity 100 cSt  8 g Crosslinker 1: Vinyl-tris(ethyllactato)silane  32 g Crosslinker 2: Methyl-tris(ethyllactato)silane  2 g Aminoalkyltrialkoxysilane (AMEO) 100 g Pyrogenic silica  1 g Catalyst 1:1 (w/w) Mixture of dialkyl zinc oxide and tetraalkoxysilane

Example 4

[0224] The following adhesion promoter was added to the sealant formulation:

TABLE-US-00006 12 g Adhesion promoter: 2,2-dimethoxy-1-(methyl)aza-2- silacyclopentane (MDC)

[0225] -Dihydroxy-dimethyl-polysiloxane 80,000 cSt, PDMS 100 cSt, vinyl-tris(ethyllactato)silane and methyl-tris(ethyllactato)silane were mixed under vacuum. The silica was then dispersed and stirred under vacuum until the mass was smooth. Then AMEO was mixed in as a thixotropic agent. The silica was then dispersed and stirred under vacuum until the mass was smooth. Finally, the catalyst as a 1:1 (w/w) mixture of dialkyl zinc oxide and tetraalkoxysilane and the adhesion promoter 2,2-dimethoxy-1-(methyl)aza-2-silacyclopentane (MDC) are mixed in under vacuum.

[0226] The resulting sealant was transparent and colorless and had a skin formation time of 5 minutes, a tack-free time of 9 minutes and a curing time on glass (sealant applied 9 mm thick on a glass plate) of 6 days. The sealant had good adhesion on all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, wood varnished, wood glazed, polyamide, Al/Mg alloy, polystyrene and Metzoplast and had a pleasant odor. The determination of the tensile strength according to DIN 53504 was 1.1 N/mm.sup.2 and the elongation at break according to DIN 53504 was determined to 1100%. The determined Shore A cureness was 27. Even after storing the sealant at 50° C. for 8 weeks, the sealant was stable (Shore A: 17) and showed only a slight, slightly yellowish discoloration. After application, the sealant becomes colorless again when exposed to light.

Example 5

[0227] Adhesion Promoter pH-DEC

TABLE-US-00007 12 g Adhesion promoter: 2,2-diethoxy-1-(phenyl)aza-2- silacyclopentane (Ph-DEC)

[0228] α,ω-dihydroxy-dimethyl-polysiloxane 80,000 cSt, PDMS 100 cSt, vinyl-tris(ethyllactato)silane and methyl-tris(ethyllactato)silane were mixed under vacuum. The silica was then dispersed and stirred under vacuum until the mass was smooth. Then AMEO was mixed in as a thixotropic agent. The silica was then dispersed and stirred under vacuum until the mass was smooth. Finally, the catalyst as a 1:1 (w/w) mixture of dialkyl zinc oxide and tetraalkoxysilane and the adhesion promoter 2,2-diethoxy-1-(phenyl)aza-2-silacyclopentane (Ph-DEC) are mixed in under vacuum.

[0229] The resulting sealant was transparent and colorless and had a skin formation time of 70 minutes, a tack-free time of 24 h and a curing time on glass (sealant applied 9 mm thick on a glass plate) of 7 days. The sealant had good adhesion on all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, wood varnished, wood glazed, polyamide, Al/Mg alloy, polystyrene and Metzoplast and had a pleasant odor. The determined Shore A cureness was 25. After storing the sealant at 50° C. for 8 weeks, the sealant was stable (Shore A: 16) and showed only a slight, slightly yellowish discoloration.

Comparative Example (Prior Art; Based on EP2030976 A1, Example 7)

Adhesion Promoter from Example 7

[0230]

TABLE-US-00008 12 g Adhesion promoter: Aminoalkyltrialkoxysilane [AMEO]

[0231] The resulting sealant has a transparent appearance after application in air and had a skin formation time of 5 minutes and a tack-free time of 32 minutes. The sealant showed poor adhesion to glass, aluminum, PVC, sheet metal, steel, wood, painted wood, varnished wood, polyamide, Al/Mg alloy, concrete, polystyrene and Metzoplast. In addition, there was no through-curing on glass (9 mm) and the storage stability at 50° C. was no longer given after only 4 days.

Example 6

Lactate Crosslinker Mixture with 2,2-dimethoxy-1-(benzyl)aza-2-silacyclopentane (Bn-DC)

[0232]

TABLE-US-00009 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.1 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 32.4 3 Crosslinker 1: Vinyl-tris(ethyllactato)silane 0.8 4 Crosslinker 2: Methyl-tris(ethyllactato)silane 3.2 5 Aminopropyltriethoxysilane (AMEO) 0.2 6 Pyrogenic silica, hydrophobic 10.0 BET surface 130-150 m2/g 7 Catalyst 1:1 (w/w) Mixture of dialkyl zinc 0.1 oxide and tetraalkoxysilane 8 Adhesion promoter: 2,2-dimethoxy-1- 1.2 (benzyl)aza-2-silacyclopentane (Bn-DC)

[0233] Polymer 80,000 cSt, PDMS 100 cSt and the crosslinker mixture of vinyl-tris(ethyllactato)silane and methyl-tris(ethyllactato)silane were mixed under vacuum. The thixotropic agent AMEO was then mixed in under vacuum. The silica was then dispersed and stirred under vacuum until the mass was smooth. The catalyst was then mixed in as a 1:1 (w/w) mixture of dialkyl zinc oxide and tetraalkoxysilane and the adhesion promoter 2,2-dimethoxy-1-(benzyl)aza-2-silacyclopentane (Bn-DC) under vacuum.

[0234] The resulting composition was transparent and colorless after curing. It was characterized by a skin formation time of 18 minutes and a tack-free time of 30 minutes. The resulting sealant had good adhesion on all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, wood varnished, wood glazed, polyamide, Al/Mg alloy, polystyrene and Metzoplast and had a pleasant odor.

[0235] The Shore A cureness was 23. Even after 8 weeks storage at 50° C., the composition was stable after curing (Shore A:17) and only showed a slightly yellowish coloration. The extrusion when using a 2 mm diameter die at 5 bar and 30 seconds was 30.0 g, and the sealant was transparent and colorless again after exposure to light. The sealant was also characterized by the following excellent properties:

TABLE-US-00010 Property Sealant Early resilience 105 min Through curing on glass 6 d (9 mm) DIN EN ISO 8339 0.29 Elongation stress value at 100% elongation (N/mm2) DIN EN ISO 8339 0.53 Secant modulus at elongation at break (N/mm2) DIN EN ISO 8339 335% Elongation at break DIN EN ISO 7389  93% Average resilience

Example 7

Lactate Crosslinker Mixture with 2,2-dimethoxy-1-(phenyl)aza-2-silacyclopentane (Ph-DC)

[0236] A silicone rubber mass was prepared according to the following composition by mixing the components analogous to the already described example formulations under vacuum:

TABLE-US-00011 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.1 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 32.4 3 Crosslinker 1: Vinyl-tris(ethyllactato)silane 0.8 4 Crosslinker 2: Methyl-tris(ethyllactato)silane 3.2 5 Aminopropyltriethoxysilane (AMEO) 0.2 6 Pyrogenic silica, hydrophobic 10.0 BET surface 130-150 m2/g 7 Catalyst 1:1 (w/w) Mixture of dialkyl zinc 0.1 oxide and tetraalkoxysilane 8 Adhesion promoter: 2,2-dimethoxy-1- 1.2 (phenyl)aza-2-silacyclopentane (Ph-DC)

[0237] The resulting sealant was transparent and colorless and had a skin formation time of 120 minutes and a tack-free time of 24 h. The resulting sealant had good adhesion to all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, painted wood, varnished wood, polyamide, Al/Mg alloy, polystyrene and Metzoplast and had a pleasant odor.

[0238] The determined Shore A cureness was 22. Even after 8 weeks storage at 50° C., the composition was stable after curing (Shore A:16) and showed only a slightly yellowish coloration, which changed back to colorless when exposed to light. The extrusion when using a 2 mm diameter die at 5 bar and 30 seconds was 24.0 g. The sealant was characterized by other excellent properties:

TABLE-US-00012 Property Sealant Early resilience 280 min Through curing on glass 7 d (9 mm) DIN EN ISO 8339 0.29 Elongation stress value at 100% elongation (N/mm2) DIN EN ISO 8339 0.51 Secant modulus at elongation at break (N/mm2) DIN EN ISO 8339 320% Elongation at break DIN EN ISO 7389  93% Average resilience

Example 8

Lactate Crosslinker Mixture with 2,2-diethoxy-1-(3-triethoxysilyipropyl)aza-2-silacyclopentane (TESPDC)

[0239] A silicone rubber mass was produced according to the following composition by mixing the components analogous to the examples already described under vacuum:

TABLE-US-00013 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.1 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 32.4 3 Crosslinker 1: Vinyl-tris(ethyllactato)silane 0.8 4 Crosslinker 2: Methyl-tris(ethyllactato)silane 3.2 5 Aminopropyltriethoxysilane (AMEO) 0.2 6 Pyrogenic silica, hydrophobic 10.0 BET surface 130-150 m2/g 7 Catalyst 1:1 (w/w) Mixture of dialkyl zinc 0.1 oxide and tetraalkoxysilane 8 Adhesion promoter: 2,2-diethoxy-1-(3- 1.2 triethoxysilylpropyl)aza-2-silacyclopentane (TESPDC)

[0240] The resulting sealant was transparent and colorless and was characterized by a skin formation time of 6 minutes and a tack-free time of 18 minutes. After curing, the compositions had good adhesion on all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, painted wood, varnished wood, polyamide, Al/Mg-alloy, polystyrene and Metzoplast and had a pleasant odor.

[0241] The determined Shore A cureness was 29. Even after 8 weeks storage at 50° C., the sealant was stable (Shore A:17) and showed only a slight yellowish coloration, but became colorless again when exposed to light. The extrusion when using a 2 mm diameter die at 5 bar and 30 seconds was 34.0 g. The sealant also had the following excellent properties:

TABLE-US-00014 Property Sealant Early resilience 105 min Through curing on glass 7 d (9 mm) DIN EN ISO 8339 0.33 Elongation stress value at 100% elongation (N/mm2) DIN EN ISO 8339 0.45 Secant modulus at elongation at break (N/mm2) DIN EN ISO 8339 270% Elongation at break DIN EN ISO 7389  93% Average resilience

Example 9

Lactate Crosslinker Mixture with 2,2-diethoxy-1-(benzyl)aza-2-silacyclopentane (Bn-DEC)

[0242] A silicone rubber mass was prepared according to the following composition by mixing the components as described above under vacuum:

TABLE-US-00015 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.1 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 32.4 3 Crosslinker 1: Vinyl-tris(ethyllactato)silane 0.8 4 Crosslinker 2: Methyl-tris(ethyllactato)silane 3.2 5 Aminopropyltriethoxysilane (AMEO) 0.2 6 Pyrogenic silica, hydrophobic 10.0 BET surface 130-150 m2/g 7 Catalyst 1:1 (w/w) Mixture of dialkyl zinc 0.1 oxide and tetraalkoxysilane 8 Adhesion promoter: 2,2-diethoxy-1- 1.2 (benzyl)aza-2-silacyclopentane (Bn-DEC)

[0243] The product was transparent and colorless and had a skin formation time of 11 minutes and a tack-free time of 21 minutes. It had good adhesion to all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, painted wood, varnished wood, wood stained, polyamide, Al/Mg alloy, polystyrene and Metzoplast and had a pleasant odor.

[0244] The determined Shore A cureness was 27. Even after 8 weeks storage at 50° C., the sealant was stable (Shore A:16) and showed only a slightly yellowish coloration, whereby the sealant became colorless again when exposed to light. The extrusion when using a 2 mm diameter die at 5 bar and 30 seconds was 30.0 g. The sealant also had an early strength of 100 minutes. The curing time on glass was determined to 7 days.

Example 10

Lactate Crosslinker Mixture with 2,2-dimethoxy-1-(n-butyl)aza-2-silacyclopentane (BDC) and Additional Stabilization by 1,3-bis(trimethylsilyl)urea (BSU)

[0245]

TABLE-US-00016 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.1 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 31.9 3 Crosslinker 1: Vinyl-tris(ethyllactato)silane 4.0 4 Crosslinker 2: Methyl-tris(ethyllactato)silane 1.0 5 Stabilizer: 1.3 bis(trimethylsilyl)urea 1.0 (BSU paste) 6 Aminopropyltriethoxysilane (AMEO) 0.2 7 Pyrogenic silica, untreated 8.5 BET surface 130-150 m2/g 8 Catalyst 1:1 (w/w) Mixture of dialkyl zinc 0.1 oxide and tetraalkoxysilane 9 Adhesion promoter: 2,2-dimethoxy-1- 1.2 (n-butyl)aza-2-silacyclopentane (BDC)

[0246] Polymer 80,000 cSt, PDMS 100 cSt are mixed under vacuum for 5 minutes. Then the crosslinker mixture of vinyl-tris(ethyllactato)silane and methyl-tris(ethyllactato)silane and the BSU paste are mixed in under vacuum for 5 minutes. Then the thixotropic agent AMEO was added under vacuum. The silica was then dispersed and stirred under vacuum until the paste was smooth. Finally, the catalyst was added as a 1:1 (w/w) mixture of dialkyl zinc oxide and tetraalkoxysilane and the adhesion promoter BDC under vacuum and the mixture was then stirred for 20 minutes.

[0247] The product was transparent and colorless and had a skin formation time of 9 minutes and a tack-free time of 21 minutes. It had good adhesion to all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, painted wood, varnished wood, wood stained, polyamide, Al/Mg alloy, polystyrene and Metzoplast and had a pleasant odor.

Example 11

Oxime Crosslinker Mixture with 2,2-dimethoxy-1-(trimethylsilyl)aza-2-silacyclopentane (TMS-DC)

[0248]

TABLE-US-00017 Component wt.-% 1 α,ω-dihydroxy-dimethyl-polysiloxane 52.0 80.000 cSt 2 Polydimethylsiloxane (PDMS) 100 cSt 30.2 3 Crosslinker 1: Vinyl-tris(2-pentanone 1.3 oximo)silane 4 Crosslinker 2: Methyl-tris(2-pentanone 2.9 oximo)silane 5 Pyrogenic silica, untreated 10.3 BET surface 130-150 m2/g 6 Catalyst 1:1 (w/w) Mixture of dialkyl zinc oxide 0.12 and tetraalkoxysilane 7 Adhesion promoter 1: 2,2-dimethoxy-1- 1.2 (trimethylsilyl)aza-2-silacyclopentane (TMS-DC) 8 Adhesion promoter 2 based on N-(2- 0.5 aminoethyl)-3-aminopropyltrimethoxysilane (DAMO)

[0249] Polymer 80,000 cSt, PDMS 100 cSt and the crosslinker mixture of oxime and oxime were mixed under vacuum. The silica was then dispersed and stirred under vacuum until the mass was smooth. Then the catalyst was mixed as a 1:1 (w/w) mixture of dialkyl zinc oxide and tetraalkoxysilane together with adhesion promoter 1 (2,2-dimethoxy-1-(trimethylsilyl)aza-2-silacyclopentane (TMS-DC)) and adhesion promoter 2 (based on N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (DAMO)) under vacuum.

[0250] The product was transparent and colorless. It was characterized by a skin formation time of 6 minutes and a tack-free time of 15 minutes. The resulting sealant had good adhesion to all tested materials, i.e. glass, aluminum, PVC, sheet metal, steel, concrete, wood, wood varnished, wood glazed, polyamide, Al/Mg alloy and had a moderately pleasant odor.

[0251] The determined Shore A cureness was 22. Even after 4 weeks storage at 60° C. the sealant was stable (Shore A:21) and colorless. The extrusion when using a 2 mm diameter die at 5 bar and 30 seconds was 24.0 g. In addition, the sealant was early loadable after 60 min and showed a curing time on glass of 4 days.

[0252] General Execution of the Test Procedures:

[0253] 1. Determination of the Tack-Free Time of Silicone Sealants

[0254] To determine the tack-free time, the temperature as well as the air humidity when the sealant is discharged must be determined using a suitable device and is to be noted in the corresponding protocol. A completely filled and closed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Afterwards, an appropriate amount of silicone is sprayed onto a clean glass plate. The spatula is brushed quickly over the silicone to create a continuous silicone strip. The current time is taken. At appropriate time intervals, the adhesion-free time of the sealant to be determined is determined by lightly touching the silicone surface with a clean finger. If the sealant is tack-free, the current time is read off again.

[0255] 2. Determination of the Extrusion of Silicone Sealants

[0256] A completely filled and sealed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a compressed air gun for silicone cartridges and a suitable cartridge tip is screwed on. The compressed air pistol is connected to the compressed air supply and a pressure of 5 bar is set at the pressure gauge. First, a small amount of silicone is sprayed from the silicone cartridge onto a wiping paper so that the cartridge tip is completely filled with silicone. Then, an aluminium bowl is placed on the top pan scale and tared. Now, silicone is sprayed on the bowl for exactly 30 seconds and the weight is read off on the top pan scale.

[0257] 3. Determination of the Stability of Silicone Sealants

[0258] To determine the stability, the temperature as well as the air humidity during the discharge of the sealant must be determined by means of a suitable device and is to be noted in the corresponding protocol. A completely filled and closed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Then, a screw form is sprayed circularly onto a cardboard box (diameter approx. 3 cm). The carton with the silicone screw is now placed vertically and the current time is read off.

[0259] After 30 minutes it is observed whether the silicone screw has the original shape or whether the screw has flowed down. If the screw shape has not changed, the silicone sealant is stable.

[0260] 4. Determination of the Curing of Silicone Sealants

[0261] To determine the curing time, the temperature as well as the air humidity during the discharge of the sealant must be determined by means of a suitable device and is to be noted in the corresponding protocol. A completely filled and closed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Afterwards, an appropriate amount of silicone is sprayed onto a clean glass plate. The spatula is brushed quickly over the silicone to create a continuous silicone strip. At appropriate intervals (days), a small cross piece is carefully cut off the silicone with a knife and the curing of the sealant is assessed. If the inner part of the sealant body is still sticky and gel-like, the sealant is not yet fully cured and the determination is repeated. If the sealant is completely cured, the curing time is noted in days. If the sealant is still sticky after 7 days after application, the criterion curing is not OK.

[0262] 5. Determination of the Adhesion of Silicone Sealants

[0263] To determine the adhesion, the temperature as well as the air humidity during the discharge of the sealant must be determined by means of a suitable device and is to be noted in the corresponding protocol. A completely filled and closed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. A silicone button is then sprayed onto an appropriate cleaned carrier material (e.g. glass, aluminum, wood, plastic, concrete, natural stone, etc.). After the complete curing of the sealant (approx. 48 h), the silicone button is pulled with the fingers to see if the silicone separates again from the carrier material or if the silicone has formed an intimate connection with the carrier material. If the silicone button can be pulled off easily, heavily or not at all from the carrier material, the adhesive property is judged as bad, medium or good.

[0264] 6. Determination of the Odour of Silicone Sealants

[0265] A completely filled and sealed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Then, an appropriate amount of silicone is sprayed onto a clean glass plate. The spatula is brushed quickly over the silicone to create a continuous silicone strip. The silicone sealant is then assessed with regard to its odour.

[0266] 7. Determination of the Aspect of Silicone Sealants

[0267] A completely filled and sealed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Then, an appropriate amount of silicone is sprayed onto a clean glass plate. The spatula is brushed quickly over the silicone to create a continuous silicone strip. The silicone sealant is then visually assessed for appearance, color and smoothness.

[0268] 8. Determination of the Skin Formation Time of Silicone Sealants

[0269] To determine the skin formation time, the temperature as well as the air humidity during the discharge of the sealant must be determined by means of a suitable device and noted in the corresponding protocol. A completely filled and closed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Afterwards, an appropriate amount of silicone is sprayed onto a clean glass plate. The spatula is brushed quickly over the silicone to create a continuous silicone strip. At appropriate intervals, the skin formation of the sealant to be determined is determined with a clean finger by light pressure on the silicone surface. If the sealant forms a skin on its surface so that no silicone residues remain on the finger, the measured time is taken from the stopwatch.

[0270] 9. Tensile Test with Shoulder Rod S1 According to DIN 53504

[0271] For the determination of the silicone to be tested, the corresponding test number of the silicone cartridge and the test date must be noted in the protocol. The service life of the sealant after compounding must be at least 24 hours in the cartridge. The casting mould is wetted with washing-up liquid to prevent silicone from adhering to the metal. A completely filled and sealed cartridge is placed in a gun for silicone cartridges. The tip of the cartridge is removed. The silicone is then sprayed onto the matrix for the shoulder rod S 1 over the length and height of the milled out casting mould and immediately smoothed out with a spatula. After at least 24 hours, the curing of the silicone is checked by lifting the test specimen out of the matrix. There must be no sticky surface left. The shoulder rod must be visually perfect, without air and foreign inclusions or cracks. The test specimen is marked with the test number after it has been removed from the die. In the T 300 tensile tester, the tension clamps for the shoulder rod S 1 must be inserted. The testable shoulder rod is clamped between the upper and lower clamps in such a way that the web shows exactly 26 mm initial gauge length. The measuring data or measuring marks are reset to zero in the relaxed state. By pressing the start button the stretching of the test specimen or its measured value display starts. The device switches off automatically after the test specimen is torn. The measured values remain displayed and can be read directly

[0272] 10. Tensile Test with H-Test Specimen According to DIN 8339

[0273] For the determination of the silicone to be tested, the corresponding test number of the silicone cartridge and the test date must be noted in the protocol. The service life of the sealant after compounding must be at least 24 hours in the cartridge.

[0274] A completely filled and sealed cartridge is placed in a gun for silicone cartridges. The tip of the cartridge is removed. The silicone is then sprayed onto the matrix over the length and height of the mould and immediately smoothed out with a spatula. The test specimen is then stored for 28 days under standard conditions. Before the tensile test, the test specimen is visually checked. The test specimen must not show any air inclusions or cracks.

[0275] In the MFC T 300 tensile tester, the tensile clamps for the H-test specimen must be inserted. The test specimen is clamped between the upper and lower clamps so that the distance is 12 mm. The measuring data or measuring marks are reset to zero in the relaxed state. By pressing the start button, the test specimen or its measured value display starts stretching. The device switches off automatically after the test specimen is torn. The measured values remain displayed and can be read off directly.

[0276] 11. Tensile Test with H-Test Specimen According to DIN 8340

[0277] For the determination of the silicone to be tested, the corresponding test number of the silicone cartridge and the test date must be noted in the protocol. The service life of the sealant after compounding must be at least 24 hours in the cartridge. A completely filled and sealed cartridge is placed in a gun for silicone cartridges. The tip of the cartridge is removed. The silicone is then sprayed onto the matrix over the length and height of the mould and immediately smoothed out with a spatula. The test specimen is then stored for 28 days under standard conditions. Before the tensile test, the test specimen is visually checked. The test specimen must not show any air inclusions or cracks.

[0278] In the MFC T 300 tensile tester, the tensile clamps for the H-test specimen must be inserted. The test specimen is clamped between the upper and lower clamps so that the distance is 12 mm. The measuring data or measuring marks are reset to zero in the relaxed state. By pressing the start button, the test specimen or its measured value display starts stretching. The device switches off automatically after the test specimen is torn. The measured values remain displayed and can be read off directly.

[0279] 12. Determination of the Storage Stability of Silicone Sealants

[0280] A completely filled and sealed cartridge is placed in the heated drying cabinet. According to the protocol Test Methods, the silicone sealant is stored at an appropriate temperature in the heated drying cabinet for a certain period of several weeks. At the end of the storage period, the cartridge is placed in a gun for silicone cartridges. Then an appropriate amount of silicone is sprayed onto a laid out flow cloth. With the spatula, the silicone is brushed quickly over the silicone, so that a continuous silicone strip is created. The silicone sealant is then evaluated with regard to PA-E0002 and PA-E0010.

[0281] 13. Determination of the Early Load Capacity of Silicone Sealants

[0282] To determine the early load-bearing capacity, the temperature as well as the air humidity during the discharge of the sealant must be determined by means of a suitable device and noted in the corresponding protocol. A completely filled and closed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Horizontal lines are first drawn on the cartridge at a distance of 3 cm each and then cut. Then, a corresponding amount of silicone is sprayed onto the cardboard. The spatula is used to stroke quickly over the silicone, so that a continuous silicone strip is created. The current time is read off. At equal intervals of 15 minutes, starting at the first line, the carton is bent to a right angle and the surface of the silicone is examined at the bend. If the silicone is completely or only partially torn at the kink, the determination is repeated at the next 3 cm line after another 15 minutes. If the silicone is elastic at the kink and no crack can be detected, the silicone is ready for early loading. The current time is read again.

[0283] 14. Determination of the Shore Cureness of Silicone Sealants

[0284] A completely filled and sealed cartridge (service life of the sealant after compounding at least 24 hours) is placed in a gun for silicone cartridges. Then, an appropriate amount of silicone is sprayed onto a clean glass plate. The spatula is brushed quickly over the silicone to create a continuous silicone strip. When the sealant is completely cured (see PA-E0008), the shore cureness meter is placed on the silicone surface with both hands in a completely flat position and the maximum value of the shore cureness is read off. The measurement is repeated at least 5 times at different points on the silicone surface and an average value is calculated from the individual measurements.

EMBODIMENTS

Embodiment 1

[0285] Composition containing [0286] a. a curing agent for silicone rubber compositions comprising a compound having the general structural formula R.sup.1.sub.mSi(R).sub.4-m, [0287] wherein [0288] each R.sup.1 independently represents an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted C4 to C14 aryl group, [0289] m is an integer from 0 to 2, [0290] each R is independently selected from the group consisting of [0291] a hydroxycarboxylic acid ester residue having the general structural formula (I):

##STR00011## [0292] wherein [0293] each R.sup.2 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, or a C4 to C14 aryl group [0294] each R.sup.3 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, or a C4 to C14 aryl group [0295] R.sup.4 represents an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group, a C5 to C15 aralkyl group or a C4 to C14 aryl group, [0296] R.sup.5 is C or an optionally substituted saturated or partially unsaturated cyclic ring system having 4 to 14 C atoms or an optionally substituted aromatic group having 4 to 14 C atoms, and [0297] n is an integer from 0 to 10, [0298] -a hydroxycarboxylic acid amide residue of the general structural formula (II):

##STR00012## [0299] wherein [0300] each R.sup.6 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, or a C4 to C14 aryl group, [0301] each R.sup.7 or R.sup.8 independently represents H or an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group or a C4 to C14 aryl group, [0302] O—C(O)—R.sup.9, wherein R.sup.9 represents H, an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group or an optionally substituted, straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group or a C4 to C14 aryl group, and [0303] O—N═CR.sup.10 R.sup.11, wherein R.sup.10 and R.sup.11 independently represent H, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group or a C4 to C14 aryl group, and [0304] b. at least one organosilane, in particular a heterocyclic organosilane as water scavenger, alcohol scavenger and/or hydroxide ion scavenger and [0305] c. optionally at least one organopolysiloxane.

Embodiment 2

[0306] Composition according to embodiment 1 characterized in that a heterocyclic organosilane is contained, wherein at least one silicon atom and at least one heteroatom are directly linked to one another and the heteroatom is selected from the group consisting of N, P, S or O.

Embodiment 3

[0307] Composition according to embodiment 1 or 2 characterized in that one or more heterocyclic organosilanes are selected from the group of the general structural formulae (III), (IIIa), (IV), (IVa), (V), (Va) or mixtures thereof:

##STR00013##

[0308] wherein [0309] a is 0, 1 or 2; [0310] x means 0 to 100; [0311] y means 1 to 1000; [0312] n means 0 to 6 [0313] each R.sup.a, R.sup.b, R.sup.c, R.sup.d, R.sup.e, R.sup.f or R.sup.g is independently H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, an optionally substituted C4 to C20 cycloalkenyl group represents an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group;
each R.sup.A and/or R.sup.B and/or (R.sup.C).sub.n taken together form a 4- to 10-membered ring, preferably a 5 to 8-membered ring, especially preferably a 5- to 6-membered ring.

Embodiment 4

[0314] Composition according to embodiment 1, characterized in that one or more organosilanes are selected from the group consisting of iminosilanes of the general structural formula (VII), silanoaminosilanes of the general structural formula (VIII), non-cyclic organosilanes of the general structural formula (IX), amino-protecting group-containing organosilanes (IXa) to (IXe) derived from the general structural formula (IX) or mixtures thereof:

##STR00014## [0315] wherein [0316] R.sup.h is C or Si, [0317] each R.sup.i, R.sup.j independently represents H, —C(O)Rt, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted C4 to C14 aryl group [0318] each R.sup.k, R.sup.l, R.sup.m independently represents H, —C(O)R.sup.1, an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted C4 to C14 aryl group [0319] each R.sup.n, R.sup.o, R.sup.p, R.sup.q, R.sup.r, R.sup.s independently represents H, —O—R.sup.t, —C(O)—R.sup.t, —COOR.sup.t, an optionally substituted, straight-chain or branched C1 to C16 alkyl group, an optionally substituted, straight-chain or branched C2 to C16 alkenyl group, or an optionally substituted C4 to C14 aryl group [0320] each R.sup.t, R.sup.u independently represents H, —OR.sup.1, —C(O)R.sup.1, —C(O)CF.sub.3, —COOR.sup.1, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group, an optionally substituted C4 to C14 aryl group, or a protecting group in particular a tert-butoxycarbonyl group, a fluorenylmethoxycarbonyl group, a benzyloxycarbonyl group, an allyloxycarbonyl group, an optionally substituted isoindole-1,3-dione group or a 3-methyl-benzenesulfone group, and [0321] z is an integer from 1 to 30.

Embodiment 5

[0322] Composition at least comprising a mixture obtainable by mixing at least one curing agent according to embodiment 1a with at least one organosilane 4b and/or a heterocyclic organosilane according to embodiment 3b.

Embodiment 6

[0323] Composition according to one of the above embodiments, wherein the organosilane, in particular heterocyclic organosilane, is contained at a maximum of 3 wt.-%, preferably at a maximum of 2 wt.-%, more preferably at a maximum of 1.5 wt.-%, in particular preferably at a maximum of 1.2 wt.-%, in each case based on the total weight of the composition.

Embodiment 7

[0324] Composition according to one of the above embodiments, wherein the organosilane, in particular heterocyclic organosilane, is present in a proportion of 0.25 to 3 wt.-%, preferably from 0.25 to 2 wt.-%, particularly preferably from 0.5 to 1.5 wt.-%, particularly preferably from 0.8 to 1.2 wt.-%, based on the total weight of the silicone rubber mass.

Embodiment 8

[0325] Composition according to any of the above embodiments, wherein the heterocyclic organosilane is a 4- to 10-membered heterocycle.

Embodiment 9

[0326] Composition according to any of the above embodiments, wherein the heterocyclic organosilane is a 5- to 6-membered heterocycle.

Embodiment 10

[0327] Composition according to one of the above embodiments, wherein the organosilane, in particular heterocyclic organosilane, consisting exclusively of silicon and heteroatoms.

Embodiment 11

[0328] Composition according to embodiment 8 or 9, wherein the heterocycle contains a maximum of 5 heteroatoms selected from the group consisting of Si, N, P, S or O.

Embodiment 12

[0329] Composition according to any one of the above embodiments 8 to 11, wherein the heterocycle containing at least one N.

Embodiment 13

[0330] Composition according to one of the above embodiments, wherein the organosilane, in particular the heterocyclic organosilane is linked with at least one further cyclic ring system.

Embodiment 14

[0331] Composition according to one of the above embodiments, wherein the silicon atom carries at least one OR.sup.d radical and each R.sup.d independently carries H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, represents an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group.

Embodiment 15

[0332] Composition according to one of the above embodiments, wherein the silicon atom carries at least one NR.sup.d1R.sup.d1 radical and each R.sup.d1 independently carries H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, represents an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group

Embodiment 16

[0333] Composition according to one of the above embodiments, wherein the heteroatom is directly linked to another organosilane, preferably to a heterocyclic organosilane.

Embodiment 17

[0334] Composition according to one of the above embodiments, wherein the heteroatom is connected via one or more carbon atoms to another organosilane, preferably to a heterocyclic organosilane.

Embodiment 18

[0335] Composition according to any of the above embodiments, wherein the heterocyclic organosilane has at least one of the following structural formulae:

##STR00015## [0336] wherein [0337] a is 0, 1 or 2; [0338] x means 0 to 100; [0339] y means 1 to 1000; [0340] n means 0 to 6; [0341] each R.sup.a, R.sup.b, R.sup.c, R.sup.d, R.sup.e, R.sup.f or R.sup.g is independently H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, an optionally substituted C4 to C20 cycloalkenyl group represents an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group; [0342] each R.sup.A and/or R.sup.B and/or (R.sup.C), taken together form a 4- to 10-membered ring, preferably a 5- to 8-membered ring, especially preferably a 5- to 6-membered ring.

Embodiment 19

[0343] Composition according to any of the above embodiments, wherein the heterocyclic organosilane has at least one of the following structural formulae:

##STR00016## [0344] wherein [0345] a is 0, 1 or 2; [0346] x means 0 to 100; [0347] y means 1 to 1000; [0348] n means 0 to 6 [0349] each R.sup.a, R.sup.b, R.sup.c, R.sup.d, or R.sup.9 is independently H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group; [0350] R.sup.A and/or R.sup.B and/or (R.sup.C).sub.n taken together form a 4- to 10-membered ring, preferably a 5- to 8-membered ring, in particular preferably a 5- to 6-membered ring.

Embodiment 20

[0351] Composition containing, [0352] a. a curing agent for silicone rubber masses comprising a compound having the general structural formula R.sup.1.sub.mSi(R).sub.4-m, [0353] wherein [0354] each R.sup.1 independently represents an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted C4 to C14 aryl group, [0355] m is an integer from 0 to 2, [0356] each R is independently selected from the group consisting of [0357] —O—N═CR.sup.10R.sup.11, wherein R.sup.10 and R.sup.11 independently represent H, an optionally substituted straight-chain or branched C1 to C16 alkyl group, an optionally substituted straight-chain or branched C2 to C16 alkenyl group or an optionally substituted straight-chain or branched C2 to C16 alkynyl group, a C4 to C14 cycloalkyl group or a C4 to C14 aryl group, and [0358] b. at least one heterocyclic organosilane having at least one of the following structural formulae:

##STR00017## [0359] wherein [0360] a is 0, 1 or 2; [0361] x means 0 to 100; [0362] y means 1 to 1000; [0363] n means 0 to 6; [0364] each R.sup.a, R.sup.b, R.sup.c, R.sup.d or R.sup.g is independently H or an optionally substituted, straight-chain or branched C1 to C20 alkyl group, an optionally substituted, straight-chain or branched C2 to C20 alkenyl group, an optionally substituted C3 to C20 cycloalkyl group, an optionally substituted C4 to C20 cycloalkenyl group, an optionally substituted, straight, branched or cyclic C4 to C20 alkynyl group or an optionally substituted, straight or branched C2 to C20 heteroalkyl group, an optionally substituted, straight, branched or cyclic C3 to C20 heteroalkenyl group or an optionally substituted C4 to C14 aryl or heteroaryl group; [0365] each R.sup.A and/or R.sup.B and/or (R.sup.C).sub.n taken together form a 4- to 10-membered ring, preferably a 5- to 8-membered ring, especially preferably a 5- to 6-membered ring.

Embodiment 21

[0366] Composition according to embodiment 20, wherein the ring taken together by R.sup.A and/or R.sup.B and/or (R.sup.C).sub.n may contain at least one heteroatom Si, N, P, S or O, preferably Si, N, or S.

Embodiment 22

[0367] Composition according to any of the above embodiments, wherein the heterocyclic organosilane has at least one of the following structural formulae:

##STR00018##

Embodiment 23

[0368] A composition according to any of the above embodiments, wherein in the general structural formula R.sup.1.sub.mSi(R).sub.4-m each R.sup.1 is independently a residue of methyl, ethyl, propyl, vinyl, phenyl or allyl.

Embodiment 24

[0369] Composition according to one of the above embodiments, wherein in the hydroxycarboxylic acid ester residue each R.sup.2 and Ware independently selected from the group consisting of H, methyl, ethyl, propyl, isopropyl, butyl, n-butyl, sec-butyl, iso-butyl and tert-butyl, in particular from the group consisting of H and methyl.

Embodiment 25

[0370] Composition according to any one of the above embodiments, wherein in the hydroxycarboxylic acid ester residue R.sup.4 is selected from the group consisting of phenyl, tolyl, naphthyl, benzyl, cyclohexyl, methyl, ethyl, propyl, isopropyl, butyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, pentyl, n-pentyl, sec-pentyl, 3-pentyl, 2-methylbutyl, iso-pentyl, 3-methylbut-2-yl, 2-methylbut-2-yl, neopentyl, hexyl, heptyl, octyl, ethylhexyl, and 2-ethylhexyl.

Embodiment 26

[0371] Composition according to one of the above embodiments, wherein in the hydroxycarboxylic acid ester residue R.sup.5 is a divalent benzene residue or R.sup.5C and R.sup.2 and R.sup.3 are H or R.sup.5C and R.sup.2H and R.sup.3 methyl.

Embodiment 27

[0372] Composition according to one of the above embodiments, wherein in the hydroxycarboxylic acid ester residue n is an integer from 1 to 5, in particular from 1 to 3, in particular 1.

Embodiment 28

[0373] A composition according to any one of the above embodiments, wherein the curing agent is selected from the group consisting of tris(methyllactato)vinylsilane, tris(ethyllactato)vinylsilane, tris(ethylhexyllactato)vinylsilane, tris(methylsalicylato)vinylsilane, tris(ethylsalicylato)vinylsilane, tris(ethylhexylsalicylato)vinylsilane, tris(2-ethylhexylsalicylato)vinylsilane, tris(isopropylsalicylato)vinylsilane, tris(methyllactato)methylsilane, tris(ethyllactato)methylsilane, tris(ethylhexyllactato)methylsilane, tris-(methylsalicylato)methylsilane, tris(ethylsalicylato)methylsilane, tris(ethylhexylsalicylato)-methylsilane, tris(2-ethylhexylsalicylato)methylsilane, tris(3-aminopropyl)methylsilane, tris(5-aminopentyl)methylsilane, tris(methyllactato)propylsilane, tris(ethyllactato)-propylsilane, tris(ethylhexyllactato)propylsilane, tris(ethylsalicylato)propylsilane, tris-(ethylhexylsalicylato)propylsilane, tris(2-ethylhexylsalicylato)propylsilane, tris(isopropylsalicylato)propylsilane, tris(3-aminopropyl)propylsilane, tris(5-aminopentyl)propylsilane, tris(methyllactato)ethylsilane, tris(ethyllactato)ethylsilane, tris(ethylhexyllactato)ethylsilane, tris(methylsalicylato)ethylsilane, tris(ethylsalicylato)-ethylsilane, tris(ethylhexylsalicylato)ethylsilane, tris(2-ethylhexylsalicylato)ethylsilane, tris(isopropylsalicylato)ethylsilane, tris(3-aminopropyl)ethylsilane, tris(5-aminopentyl)ethylsilane, tris(methyllactato)phenylsilane, tris(ethyllactato)phenylsilane, tris(ethylhexyllactato)phenylsilane, tris(methylsalicylato)phenylsilane, tris(ethylsalicylato)phenylsilane, tris(ethylhexylsalicylato)phenylsilane, tris(2-ethylhexylsalicylato)phenylsilane, tris(isopropylsalicylato)phenylsilane, tris(3-aminopropyl)phenylsilane, tris(5-aminopentyl)phenylsilane, tetra(methyllactato)silane, tetra(ethyllactato)silane, tetra(ethylhexyllactato)silane, tetra(ethylhexylsalicylato)silane, tetra(2-ethylhexylsalicylato)silane, tetra(methylsalicylato)silane, tetra(isopropylsalicylato)silane, tetra(ethylsalicylato)silane, tetra(3-aminopropyl)silane, tetra(5-aminopentyl)silane and mixtures thereof.

Embodiment 29

[0374] Composition according to one of the above embodiments, wherein the curing agent additionally contains a compound with the general structural formula R.sup.12.sub.oSi(R).sub.4-o, wherein R.sup.12 is an optionally substituted, straight-chain or branched C1 to C16 alkyl group, in particular an optionally substituted, straight-chain or branched C1 to C12 or a C1 to C8 alkyl group or a methyl or propyl group, or an optionally substituted straight-chain or branched C2- to C16-alkenyl group, in particular an optionally substituted, straight-chain or branched C2- to C12- or a C2- to C8-alkenyl group or a vinyl group or an optionally substituted C4- to C14-aryl group or a phenyl group and R is defined according to one of claims 1, 15 or 21 and o is an integer from 0 to 2 and wherein R.sup.1.sub.mSi(R).sub.4-m and R.sup.12.sub.oSi(R).sub.4-o cannot be the same.

Embodiment 30

[0375] Composition obtainable by mixing at least one curing agent according to one of the embodiments 1 or 23 to 28 or a curing agent mixture according to embodiment 29 with an organosilane, in particular heterocyclic organosilane according to one of the embodiments 1 to 22.

Embodiment 31

[0376] Composition according to one of the above embodiments, comprising at least one organopolysiloxane, preferably a α,ω functional diorganopolysiloxane.

Embodiment 32

[0377] Composition according to embodiment 31, wherein at least one of the at least one organopolysiloxane is a α, ω-dihydroxydialkylorganopolysiloxane, preferably a α, ω-dihydroxydi-C.sub.1-6-alkylorganopolysiloxane and particularly preferably a α, ω-dihydroxydimethylpolysiloxane.

Embodiment 33

[0378] Composition according to embodiment 31 or 32, wherein at least one of the at least one organopolysiloxane has a viscosity of 1,000 to 500,000 cst, preferably of 20,000 to 200,000 cst and particularly preferably of 50,000 to 125,000 cst.

Embodiment 34

[0379] A composition according to any of the above embodiments, comprising a filler preferably selected from the group consisting of silicas, carbon black, quartz, chalks, metal salts, metal oxides and any mixtures of two or more of the foregoing compounds, most preferably silica and most preferably silica having a BET specific surface area of 100 to 200 m.sup.2/g.

Embodiment 35

[0380] A composition according to any one of the above embodiments, which contains a thixotropic agent which is preferably aminopropyltriethoxysilane.

Embodiment 36

[0381] Composition according to any of the above embodiments, comprising a plasticizer which is preferably a polydiorganosiloxane without functional end groups, more preferably a polydialkylsiloxane without functional end groups, more preferably a polydi-C.sub.1-6-alkylsiloxane without functional end groups and most preferably a polydimethylsiloxane without functional end groups.

Embodiment 37

[0382] Composition according to any of the above embodiments, comprising at least one catalyst preferably selected from the group consisting of tin carboxylates, titanium, zirconium or aluminium compounds, more preferably selected from the group consisting of titanium silsesquioxanes (Ti-POSS), dibutyl tin dilaurate, dibutyl tin divaleriate, dibutyl tin diacetate, dibutyl tin dineodecanoate, dibutyl tin diacetylacetonate, dioctyl tin bis(2-ethylhexanoate), dibutyl tin dimaleate, tin (II) octoate and butyl tin tris(2-ethylhexanoate), and most preferably selected from the group consisting of (iBu).sub.7Si.sub.7O.sub.12TiOEt, (C.sub.3H.sub.17).sub.7Si.sub.7O.sub.12TiOEt, dibutyltin dilaurate, dibutyltin diacetate and tin(II) octoate.

Embodiment 38

[0383] Composition according to one of the above embodiments, wherein it contains: [0384] a) 30 to 70 wt.-% α, ω-dihydroxydialkylorganopolysiloxane, [0385] b) 1 to 10 wt.-% of the curing agent and [0386] c) 0.1 to 10 wt.-% of organosilane, in particular heterocyclic organosilane.

Embodiment 39

[0387] Composition according to embodiment 38, wherein it contains: [0388] a) 30 to 70 wt.-% α, ω-dihydroxydialkylorganopolysiloxane, [0389] b) 1 to 10 wt.-% of the curing agent, [0390] c) 0.1 to 10 wt.-% of organosilane, in particular heterocyclic organosilane, [0391] d) 20 to 50 wt.-% plasticizer, [0392] e) 1 to 20 wt.-% filler and [0393] f) 0.01 to 1 wt.-% catalyst.

Embodiment 40

[0394] Composition according to embodiment 39, wherein it contains: [0395] a) 40 to 60 wt.-% α, ω-dihydroxydialkylorganopolysiloxane, [0396] b) 3 to 7 wt.-% of the curing agent, [0397] c) 0.5 to 2.5 wt.-% of organosilane, in particular heterocyclic organosilane, [0398] d) 25 to 40 wt.-% plasticizer, [0399] e) 5 to 15 wt.-% filler and [0400] f) 0.05 to 0.5 wt.-% catalyst.

Embodiment 41

[0401] A process for preparing a composition comprising the following steps: [0402] (i) Mixing an organopolysiloxane, preferably of a α, ω-dihydroxydialkylorganopolysiloxane with a crosslinker or crosslinker mixture according to one of the above embodiments 1 to 40 under vacuum; [0403] (ii) Mixing in under vacuum of an organosilane, in particular heterocyclic organosilane according to one of the above embodiments 1 to 40 and a catalyst according to embodiment 37.

Embodiment 42

[0404] A process for preparing a composition comprising the following steps: [0405] (i) Mixing an organopolysiloxane, preferably of a α, ω-dihydroxydialkylorganopolysiloxane with a plasticizer according to embodiment 36 and a crosslinker or crosslinker mixture according to one of the above embodiments 1 to 40 under vacuum; [0406] (ii) Addition of a thixotropic agent, preferably aminopropyltriethoxysilane; [0407] (iii) Dispersion of a filler, especially silica; [0408] (iv) Mixing in under vacuum of an organosilane, in particular heterocyclic organosilane according to one of the above embodiments 1 to 40 and a catalyst according to embodiment 37.

Embodiment 43

[0409] Use of an organosilane, in particular heterocyclic organosilane according to one of the above embodiments as a water scavenger, alcohol scavenger and/or hydroxide ion scavenger.

Embodiment 44

[0410] Use of a composition according to any one of the above embodiments 1 to 40 for the manufacture of a silicone rubber mass.

Embodiment 45

[0411] Use of a reaction product of at least one organosilane, in particular heterocyclic organosilane according to one of the above embodiments 1 to 40 with water, as adhesion promoter.

Embodiment 46

[0412] Use of a composition according to one of the above embodiments as a sealant, adhesive, casting compound or coating agent.

Embodiment 47

[0413] Use of an organosilane, in particular a heterocyclic organosilane according to one of the above embodiments, as a stabilizer, wherein the latter carries a trialkylsilyl group, preferably a trimethylsilyl group, on at least one heteroatom.