CA1128685A

CA1128685A - Process for bonding inorganic materials

Info

Publication number: CA1128685A
Application number: CA281,446A
Authority: CA
Inventors: Michael Roth; Konrad Gogolok
Original assignee: Wacker Chemie AG
Current assignee: Wacker Chemie AG
Priority date: 1976-07-21
Filing date: 1977-06-27
Publication date: 1982-07-27
Also published as: FR2359098A1; DE2632835C3; CH631426A5; ATA524677A; BE856926A; IT1079734B; DE2632835B2; FR2359098B1; DE2632835A1; GB1524790A; AT369353B

Abstract

ABSTRACT OF THE DISCLOSURE

A composition and process-are provided for bonding inorganic materials. The composition is a water-free composition comprising a bis(trialkoxysilyl)alkane and a hydrolysis catalyst. The process includes contacting the inorganic materials with an alkoxy-containing silicon com-pound in which at least a portion of the alkoxy-containing silicon com-pound is a bis(trialkoxysilyl)alkane in the presence of a hydrolysis catalyst, and then allowing hydrolysis in the presence of water. This process imparts hydrophobic properties to bonded inorganic materials, and also improves the strength of such bonded inorganic materials.

Description

The present invention relates to a process for bonding inorganie materials and more particularly to a process for bonding inorganic materails with alkoxy-containing silicon compounds.
It was known that alkyl silicates, i.e., alkoxy-containing silicon compounds which are either dissolved in an organic solvent or dispersed in water just prior to application have been used as bonding agents for inorganic materials. Also, it was known that hydrolysis catalysts may be incorporated in these compositions to accelerate the hydrolysis of the alkyl silicates while in contact with the inorganic 10 materials. (See, for example, M. Weist, "Technische Anwendungsmoglish-keiten von Kieselsaureestern" in Chemische Technik, (1954), 63 - 70;
W. ~rings and W. Dittrich, "Bindemittel auf Athylsilikatbasis fur keramische ~aterialien" in Sprechsaal fur Keramik-Glas-Email, (1960), 126 - 12a, and Canadian Patent No. 1,027,308).
Compositions which contain alkyl silicates or solutions of alkyl silicates in organic solvents have certain advantages over alkyl silicates which are mixed with water. For example, these compositions can be stored indefinitely under anhydrous conditions and when applied to inorganie materials, will penetrate further into the bonded inorganie 20 materials, thereby aehieving a stronger bond between the bonded materials.
Therefore, it is an object of one aspect of this invention to provide a composition for use in-a novel process for bonding inorganie materials.
:, .
An objeet of another aspect of this invention is to provide a process for bondlng inorganic materials, especially with an alkoxy-eontaining silicon compound.
An object of still another aspect of this inv`ention is to pro-vide a process for imparting hydrophobie properties to bonded inorganic materials.
An object of a further aspect of this invention is to provide ... .. , , , , . , ., .; . ............ . . . .

- ~ , ., " ": ," , il,,;,,", " ~ 1,,, ,;, ", ", ~ "
~ ? ` ~i a process for improving the strength of bonded inorganic materials.
The present invention in its broad aspects provides a water-free binding composition for inorganic materials, comprising a bis(tri-alkoxysilyl)alkane and a hydrolys~s catalyst.
By another aspect of this invention, an improvement is provided in an improved process for bonding inorganic materials by contacting the inorganic materials with an alkoxy-containing silicon compound and a hydrolysis catalyst, the improvement which comprises contacting inorganic materials selected from the class consisting of concrete, mortar, sand-stone, fired clay, sands, mica plates and asbestos-cement products with a composition which is substantially free of water, the composition com-prising an alkoxy-containing silicon compound in which at least a portion of the alkoxy-containing silicon compound is bis(trialko~ysilyl)alkane, an organic solvent and a hydrophobic agent, the bis(trialkoxysilyl)-alkane being present in an amount of Erom 2 to 97.99% by weight based on the weight of the alkoxy-containing silicon compound, organic solvent, hydrophobic agent and hydrolysis catalyst.
In the process of another aspect of this invention, for bonding inorganic materials according to one aspect of this invention, a composi-tion comprising a hydrolysis catalyst and a silicon compound containingalkoxy groups in which at least a portion of the alkoxy-containing silicon compound is a bis(trialkoxysilyl)alkane, is applied to the inorganic materials and thereafter cured in the presence of moisture. ~`

,, ~
' : .

.
~i\ - 3 -,. , ,~ , . . ~, : , . . .

The bis~(trialkoxysilyl)-alkanes- which may be employed in the process of aspects of this invention are represented by the general formula (RO)3SiR'Si(OR)3, where R is an alkyl radical and R' is a divalent, aliphatic hydrocarbon radical which is free of aliphatic unsaturation.
In the bls-(trialkoxysilyl)-alkanes employed in this invention, R preferably has from 1 to 4 carbon atoms, e.g. the methyl, ethyl, n-- propyl, isopropyl, n-butyl and sec.-butyl radical. Preferably the OR
radical is an ethoxy radical, since these compounds are readily available, they are easily hydrolyzed and the ethanol released during the hydrolysis does not present a health ha~ard~
Furthermore, it is preferred that the R' radicals in the bis-(trialkoxysilyl)-alkanes contain from 1 to 18 carbon atoms. Examples of such R' radicals are the methylene, ethylene, trimethylene, tetramethylene, nexamethylene and octadecylmethylene radicals.
Bis-(trialkoxysilyl)-alkanes canj for example, be prepared by reacting trialkoxysilanes with~alkenyltrialkoxysilanes or by reacting tri-cXlorosilane with alkenyltrichlorosilanes or alkenyl-trialkoxysilanes, and thereafter substituting alkoxy groups for the chlorine atoms bonded to ~0 silicon. Also, bis-(trialkoxysilyl)-alkanes can be obtained from the addition of trialkoxysilanes to aliphatic hydrocarbons having two double bonds, e.g., butadiene, or to alkines, e.g.,)acetylene, or the addition of trichlorosilane to aliphatic hydrocarbons having two double bonds, e.g., butadiene, or to alkines, e.g., acetylene and thereafter substituting alkoxy groups for the chlorine atoms bonded to silicon.

`

....... l ~-~

The amount of bis-(trialkoxysilyl)-a'lkane present based ' n the total weight of the alkoxy containing silicon compound, rganic solvent, hydrolysis catalyst and agents which induce hydro-hobic properties to the inorganic substances, should range from

2 to 97.99 percent by weight and more preferably from O to 80 percent by weight. Up to 90 percent by weight and ~
ore preferably up to 60 percent by weight of the bis-(tri- `
' lkoxysilyl)-alkanes can be substituted with alkyl silicates and/or `
exaalkoxydisiloxanes which have been used heretofore for bon'ding norganic substances~ e. g., tetraethylsili'cate and hexaethoxy-isiloxane, The presence of bis-(trialkoxysilyl)-alkanes reduces he vapor pressure of the alkylsilicates or hexaalkoxydisiloxanes nd/or the impurities present in the hexaalkoxydisiloxanes. ' ' Hydrolysis catalysts which may be employed are neutral ompounds , e- g-~ metal salts of carboxylic acid and/or organo- ~
etallic salts of carboxylic acids, e. g., those of the electro- ;
otive serles of from lead to manganese (cf. "Handbook of Chemistry nd Physics", 31st Edition, Cleveland, Ohio, 1949, page 1465.) xamples of such salts are tin carboxylic acid salts or organotin-arboxylic acid salts such as dibutyltin dilaurate, dibutyltin iacetate, tin-II-octoate, a mixture o~ dibutyltin diacylates, in ' hich the acylate groups are derived from carboxylic acids which ave from 9 to 11 carbon atoms per molecule and where the carboxyl roups are bonded to a tertiary carbon atom in at least 90 per-ent by weight of the acids. Other catalysts are diacyloxytetra- ' lkyldistannoxanes~ e- g-, diacetoxytetrabutyldistannoxane and ioleoyltetramethyldistannoxane, ferrioctoate, lead octoate, lead ~
aurate and cobalt naphthenate. Additional examples of hydrolysis , :
,~ . . , ~ . j, catalysts are acids, e.g., hydrogen chloride and basic organic nitrogen compounds, e.g., nonoethanolamine and piperidine. Mixtures of various hydrolysis catalysts may also be employed.
The amount of hydrolysis catalysts present based on the total weight of the alkoxy containing silicon compound, organic solvent, hydro-lysis catalyst and the hydrophobic agents should range from 0.01 to 10 percent by weight and more preferably from 0.1 to 5 percent by weight.
When hydrophobic agents are employed in the process of aspects of this invention, these agents can be the same compounds which have been used heretofore in the presence of organic solvents to induce water-repellency to bu;lding materials.
Organosilicon compounds are the preferred agents for imparting hydrophobic properties to inorganic materials. Examples of organosilicon compounds which may be employed are organosilanes having the general formula:
R''nSi(OR)4-n' in which R is the same as above, Ri' which may be the same or different represents monovalent hydrocarbon radicals having from l to 18 carbon atoms which are free of aliphatic unsaturation and n is 1, 2 or 3, but on the average n is from 0.9 to 1.8, and organopolysiloxanes having units of general formula:
R~Sxi(OR)y(o~)zHm)4-~-y-z-m where R and R" are the same as above, x, y and æ are 0, 1, 2 or 3, and the sum of x+y+z+m is no more than 3, where the average value of x is 0.9 to `~
1.8 and preferably from 0.9 to 1.3, the average value of y and z is 0.00 o 0.20, with the provision that at least '' .

' -one of the values of y and z must be at least 0.01 and m is 0 or 1.
It is preEerred that the organopolysiloxanes described above, have on the average no more than 30 mol percent of units in which n is 2 or 3 and that their viscosity in 50 percent by weight toluene solution not ex-ceed 10.000 cSt at 25C.
Examples of hydrocarbon radicals represented by R" are alkyl radicals, e g., the methyl, ethyl, n-propyl, isopropyl, n-butyl and sec.-butyl radicals as well as pentyl, octyl and octadecyl radicals; aryl radi-cals, e.g., the phenyl radical; alkaryl radicals, e.g., the tolyl radical;
10 and aralkyl radicals such as the benzyl radical. Because of their availa-bility, it is preferred that at least 50 percent of the R" radicals be methyl radicals.
Examples of other materials which impart hydrophobic properties to inorganic substances are organic resins, e.g., polymethylacrylates and polyacrylates in organic solvents, vinylchloride copolymexs which are soluble in varnish solvents, epoxy xesins, unsaturated alkali-resistant polyester resins, highly chlorinated polyolefins and chlorinated rubber; as well as saturated aliphatic (abs.). Mixtures of various materials which impart hydrophobic properties to inorganic substances may be employed.
When hydrophobic agents are used in the composition used in the process of aspects of this invention, they are generally employed in an a unt of from 1 to 95.99 perceDt, and more preferably in an amount of from 20 to 80 percent by weight based on the total weight of the alkoxy contain-ing silicon compound, organic solvent, hydrolysis catalyst and the hydro-phobic agent.

'~

- ~

It is preferred that the alkoxy containing silicon com-I ~ounds, the hydrolysis catalysts and the agents which impart ydrophobic properties to the inorganic materials be dissolved in ~n organic solvent. Organic solvents which are used are the same 5 ~s those which have been used heretofore in compositions for bonding norganic materials using alkylsilicates. In order that the organic ;olvents will evaporate within an acceptable period of time it is ~referred that the boiling points of these solvents not exceed -~50C at 760 mm Hg (abs.). Examples of suitable solvents are ydrocarbons , e. g., alkanes or mixtures thereof having boilingoints in the range of from 120 to 180C, toluene, xylene, tri-ethylbenzene, styrene and a~mixture of solvents which is commer- ~
ially available under the Trade Mark "Deasol 99" ,, which has a boiling range of from 155 lS I,to 175C at 760 mm Hg (abs.), and consists of 99 percent by weight ~f aromatics having 9 or lO carbon atoms; chlorohydrocarbons ,~e. g., trichloroethylene; alcohols, e. g., ethanol, isopropanol and piacetone alcoholj ketones, e. g., acetone and methylethylketone;
s well as esters , e- g., ethyl acetate and ethers, e, g., :
-dibutyl ether. In order to enhance the penetration of the rganosilicon compounds into the materials to be bonded and in order o achieve rapid hydrolysis, it is preferred that the organic olvent or at least a portion of the organic solvents be miscible ith water. Examples of such solvents are alcohols and ketones.
1 The amount of organic solvent present in the composition s not critical and may range up to 97.99 pe~cent by weight_ _ _ , ~nd ore preferably from 10 to 50 percent by welght ba~ed ~n the weight of the alkoxy containing silicon compound, organic solvent, hydrolysis catalyst and the hydrophobic inducing agent.
In comparison with the monomeric alkyl silicates and hexa- ~
alkoxydisiloxanes the alkoxy containing silicon compounds employed in r:
the process of an aspect of this invention has a lower vapor pressure, which reduces the evaporation from the inorganic materials prior to hydrolysis, thereby substantially improving the strength of the bonded materials~ Also, the alkoxy containing silicon compounds used in the process of an aspect of this invention produce bonded materials having substantially improved strength over materials which have been treated with alkoxypolysiloxanes. The alkoxy containing silicon compounds employed in the process of an aspect of this invention have certain other advantages over alkoxy containing silicon compounds, e.g., hexaalkoxy- _ disiloxanes, alkoxypolysiloxanes and the partial hydrolysates disclosed in United States Patent ~o. 2,706,72~. For example, it is no longer necessary to incur the added expense of partially hydrolyzing monomeric alkyl silicates. Moreover, the alkoxy containing silicon compounds employed in the process of an aspect of the present invention can be r~
easily prepared and are substantially free of impurities, whereas the ~-preparation of hexaalkoxydisiloxanes and the other previously mentioned polysiloxanes often results in mixtures having varying amounts of rela-tively low-molecular weight products, including raw materials, as well as products having undesirably high molecular weights. Moreover, the relatively low-molecular weight products obtained from the partial hydrolysis of monomeric alkylsilicates can evaporate off prior to ~ :`
hydrolysis with the materials to be bonded. Furthermore, the high-molecular weight products obtained from the partial hydrolysis of mono- ¦meric alkylsilicates can agglomerate on the surface of the material to be bonded and thus form an undesirable so-called "shell structure".
Inorganic materials which can be bonded with the composition described herein according to the process of aspects of this invention are, for example, molded ob~ects and coatings made of concrete or mortar, . ,, sandstone, primarily stone objects made of natural sandstone which are to be made weather-resistant, as well as objects made of fired clay, sands, powders made of inorganic materials, mica plates and asbestos~
cement products.
The compositions described herein according to the process of aspects of this invention are generally employed in amounts of from 5,000 grams and more preferable in amounts of from 1,000 to 2jO00 grams based on the total weight of all components for each square meter f r surface of inorganic materials to be bonded or strengthened.
The terms "bonding" or "binding" as used herein are analogous to the term "bonding agent" and are also intended to encompass the term "strengthening". These terms have been used heretofore in the literature in conjunction with alkylsilicates as bonding agents or as strengthening r agents.
These compositions may be contacted with the inorganic materials by any suitable means known in the art, for example by immer-sion, pouring, coating9 spraying, rolling or by means of simple mixing.
All parts and percentages given in the following examples are by weight unless otherwise specified.
The bis-~trialkoxysilyl)-alkane employed in the example was prepared in the following manner:
19.5 mols of ethanol is added dropwise to 3 mols of bis-(tri-chlorosilyl~-ethane at room temperature with constant ~.'' ' - 9a - ~
'.~ ..

.

l ~
:~
gitation. Following the addition of the ethanol, the mixture is eated to boil-ng and refluxed for a period of 3 hours. After ooling to room temperature9 it is neutralized with gaseous ammonia, iltered and the excess ethanol removed by distillation. Bis-(tr;-~thoxysilyl)-ethane is obtained: (nD25 = 1.4112, D25OC = 0.962, . ¦viscosity 2.3 cSt at 20C~ Yield: 87 percent of theoretical.
EXAMPLE
450 parts of a mixture containing 2 parts of white . ime (cf. DIN Standard No. 1,060), 1 part of white Portland cement, .5 parts of sand haviny a particle size less than 1.5 mm and 0.5 art of iron oxide are first m;xed with 1,350 parts of standard ~and and then with 250 parts of water. The mortar mixture so ~btained is placed in glass rings having an inside diameter of 8.5 m, and 5 cm high and allowed to solidify. After 24 hours the ;
~ortar discs thus obtained are removed from the glass rings and ~llowed to dry at room temperature for 14 days.
¦ The mortar discs are then immersed for 3 minutes in a ~ixture containing the alkoxy containing silicon compounds listed lin the following table, and 25 parts of a mixture containing:
18.00 parts methylethylketone, 5.75, parts acetone and 1.25 parts ibutyltin dilaurate.
The mortar discs so treated are then stored for 4 weeks t a relative air humidity of 100 percent. The compressive strength of the samples are then obtained. The following table lists the ~
25 esults obtained as the average values for each group of 5 specimens ;
. . . '..
.. . . ,~

;

TABLE

est Sil;con compound Parts by Compressive strength ~o. ~;th alkoxy groupsweight kp/cm2 or kg/cm2 Bis-(triethoxysi- 75 85.2 lyl)-ethane :
Bis-(triethoxysi- 37.5 .
lyl)-ethane ~:
. 82.5 ¦ Hexaethoxydisiloxane 37.5 .
~omparison Examples 13 - - 3.2 .
4 Hexaethoxydisiloxane 75 70.8 : ' 1, ,.. .
`,`.

: ~
. ~ . ~, ` I ~
~.
~ . ~:, ! -11 -, I . , I ,:

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A water-free binding composition for inorganic materials, comprising a bis-(trialkoxysilyl)-alkane of the general formula (RO)3Si - R1- Si(OR)3, in which R denotes an alkyl radical and R1 denotes an alkylene radical, and a hydrolysis catalyst.

2. A composition as claimed in claim 1 wherein said bis-(tri-alkoxysilyl)-alkane is of the general formula as claimed in claim 1, in which each alkyl radical denoted by R has not more than 4 carbon atoms.

3. A composition as claimed in claim 2 wherein said bis-(tri-alkoxysilyl)-alkane is of the general formula as claimed in claim 1, in which each alkyl radical denoted by R is an ethyl radical.

4. A composition as claimed in claim 1 wherein, in the said bis-(trialkoxysilyl)-alkane, each alkylene radical denoted by R1 has not more than 18 carbon atoms.

5. A composition as claimed in claim 1 wherein said bis-(tri-alkoxysilyl)-alkane is bis-(triethoxysilyl)-ethane.

6. A composition as claimed in claim 1 which additionally com-prises an alkyl silicate other than a bis-(trialkoxysilyl)-alkane.

7. A composition as claimed in claim 6 which additionally con-tains at least one alkyl silicate selected from a tetraalkoxysilane and a hexaalkoxydisiloxane as said other alkyl silicate.

8. A composition as claimed in claim 7 which additionally con-tains at least one alkyl silicate selected from a tetraethoxysilane and a hexaethoxydisiloxane as said other alkyl silicate.

9. A composition as claimed in claim 6 wherein said other alkyl silicate is present in an amount not exceeding 90% by weight of the total amount of alkyl silicates.

10. A composition as claimed in claim 9 wherein said other alkyl silicate is present in an amount not exceeding 60% by weight of the total amount of alkyl silicates.

11. A composition as claimed in claim 1 wherein said hydrolysis catalyst comprises at least one member of the group consisting of a metal salt of a carboxylic acid and an organometallic salt of a carboxylic acid.

12. A composition as claimed in claim 11 wherein said metal of the said metal salt or of said organometallic salt is one between lead and manganese (inclusive) in the electropotential series.

13. A composition as claimed in claim 12 wherein said hydrolysis catalyst comprises at least one member of the group consisting of a tin carboxylate and an organotin carboxylate.

14. A composition as claimed in claim 6 which additionally con-tains a hydrophobic agent.

15. A composition as claimed in claim 14 wherein said hydro-phobic agent is an organoalkoxysilane of the general formula R2nSi(OR)4-n' in which R is an alkyl radical, R2 denotes a monovalent hydrocarbon radical having up to 18 carbon atoms and free of aliphatic unsaturation, and n denotes 1, 2 or 3, with an average value of from 0.9 to 1.8.

16. A composition as claimed in claim 14 wherein said hydro-phobic agent is an organopolysiloxane consisting of units of the general formula R2xSi(OR)y(OH)zHmO(4-x-y-z-m)/2' in which R is an alkyl radical, R2 is a monovalent hydrocarbon having up to 18 carbon atoms and free of aliphatic unsaturation, m denotes 0 or 1, each of x, y and z denotes 0, 1, 2 or 3, with the provisos that the sum x+y+z+m does not exceed 3, the average value of x is from 0.9 to 1.8, the average value of each of y and z is from 0.00 to 0.20, and at least one of y and z has an average value of at least 0.01.

17. A composition as claimed in claim 14 which additionally con-tains an organic solvent.

18. A composition as claimed in claim 17 wherein said organic solvent has a boiling point not exceeding 250°C. at 760 torr.

19. A composition as claimed in claim 18 wherein said organic solvent comprises a water-miscible organic solvent.

20. A composition as claimed in claim 19 wherein said organic solvent comprises an alcohol or a ketone.

21. A composition as claimed in claim 17 wherein said hydro-phobic agent is present in an amount within the range of from 1 to 95.99%
by weight, based on the total amount of alkyl silicate, hydrolysis cata-lyst, hydrophobic agent and organic solvent.

22. A composition as claimed in claim 21 wherein said hydro-phobic agent is present in an amount within the range of from 20 to 80%
by weight, based on the total amount of alkyl silicate, hydrolysis cata-lyst, hydrophobic agent and organic solvent.

23. A composition as claimed in claim 17 wherein said organic solvent is present in an amount of up to 97.99% by weight, based on the total amount of alkyl silicate, hydrolysis catalyst, organic solvent and hydrophobic agent.

24. A composition as claimed in claim 23 wherein said organic solvent is present in an amount of from 10 to 50% by weight, based on the total amount of alkyl silicate, hydrolysis catalyst, organic solvent and hydrophobic agent.

25. A composition as claimed in claim 14 wherein said alkyl silicate is present in a total amount within the range of from 2 to 97.99%
by weight, based on the total amount of alkyl silicate, hydrolysis cata-lyst, hydrophobic agent and organic solvent.

26. A composition as claimed in caims 17 or 25 wherein said alkyl silicate is present, in a total amount with the range of from 20 to 80% by weight, based on the total amount of alkyl silicate, hydrolysis catalyst, hydrophobic agent and organic solvent.

27. A composition as claimed in claim 1 wherein said hydrolysis catalyst is present in an amount within the range of from 0.01 to 10% by weight, based on the total amount of alkyl silicate, hydrolysis catalyst, hydrophobic agent and organic solvent.

28. A composition as claimed in claim 27 wherein said hydrolysis catalyst is present in an amount within the range of from 0.1 to 5% by weight, based on the total amount of alkyl silicate, hydrolysis catalyst, hydrophobic agent, and organic solvent.

29. A process for binding an inorganic material, which comprises:
applying, to said material, a composition comprising a bis-(trialkoxysilyl)-alkane and a hydrolysis catalyst; and allowing said composition to hydrolyze in the presence of water.

30. A process as claimed in claim 29 wherein said water is atmospheric moisture.

31. A process as claimed in claim 29 wherein said composition is applied in an amount of from 30 to 5000 g per square meter of the inorganic material to be bound.

32. A process as claimed in claim 31 wherein said composition is applied in an amount of from 1000 to 2000 g per square meter of the inorganic material to be bound.

33. A process as claimed in claims 30, 31 or 32 wherein said inorganic material is a sandstone.

34. In an improved process for bonding inorganic materials by contacting said inorganic materials with an alkoxy-containing silicon compound and a hydrolysis catalyst, the improvement which comprises:

contacting inorganic materials selected from the class consisting of con-crete, mortar, sandstone, fired clay, sands, mica plates and asbestos-cement products with a composition which is substantially free of water, said composition comprising an alkoxy-containing silicon compound in which at least a portion of said alkoxy-containing silicon compound is bis-(tri-alkoxysilyl)-alkane, an organic solvent and a hydrophobic agent, said bis-(trialkoxysilyl)-alkane being present in an amount of from 2 to 97.99%
by weight based on the weight of said alkoxy-containing silicon compound, said organic solvent, said hydrophobic agent and said hydrolysis catalyst.

35. The improved process of claim 34 wherein said bis-(trialk-oxysilyl)-alkane is present in an amount of from 20 to 80% by weight based on the weight of alkoxy-containing silicon compound, organic solvent, hydrophobic agent, and hydrolysis catalyst.

36. The improved process of claim 34 wherein said bis-(trialkoxy-silyl)-alkane is bis-(triethoxysilyl)-ethane.

37. The improved process of claim 34 wherein said hydrolysis catalyst is a metal salt of a carboxylic acid.

38. The improved process of claim 34 wherein said hydrolysis catalyst is present in an amount of from 0.01 to 10 percent by weight based on the weight of the alkoxy-containing silicon compound, organic solvent, hydrophobic agent and hydrolysis catalyst.

39. The improved process of claim 34 wherein said hydrophobic agent is present in an amount of from 1 to 95.99% by weight based on the weight of the alkoxy-containing silicon compound, organic solvent, hydro-phobic agent and hydrolysis catalyst.