DK175833B1 - Aqueous silicone-based dispersions which can be cross-linked to an elastomer by elimination of water - Google Patents

Abstract

The present invention relates to an aqueous silicone dispersion which crosslinks to give an elastomer by elimination of water and which comprises: 100 parts of an emulsion (A) of the oil-in-water type, of an alpha , omega -(dihydroxy)polydiorganosiloxane stabilised with an anionic and/or nonionic surfactant, 1 to 100 parts of a hydroxylic silicone resin which, per molecule, exhibits at least 2 different units chosen from among those of the formulae R3SiO0.5, R2SiO, RSiO1.5 and SiO2 and having a content of hydroxyl groups of between 0.1 and 10% by weight, 0 to 250 parts of a non-siliceous inorganic filler and 0.01 to 3 parts of a metal compound which acts as a hardening catalyst, the said emulsion having a pH which is generally between 4 and 13 and a solids content of at least 40%. Use of the emulsions for the production of silicone elastomer joints, especially in the building industry.

Description

DK 175833 B1

The present invention relates to aqueous silicone-based dispersions which can be cross-linked to an elastomer by elimination of water. U.S. Pat. No. 2,891,920 discloses a process for polymerization in emulsion of polydiorganosiloxane using an acidic or basic catalyst in the presence of anionic, cationic, or nonionic surfactants. This patent discloses that the emulsions obtained are stable during storage and that they can be used after the addition of fillers to form paints which provide a continuous coating with elimination of the water.

U.S. Patent No. 3,294,725 specifically mentions the use of dodecylbenzenesulfonic acid for emulsion polymerization of polydiorganosiloxanes. It is mentioned in this publication that it is desirable to obtain stable emulsions to regulate the pH of these emulsions to a value of about. 7. This document discloses that from these neutralized emulsions to which colloidal silica and a polyalkoxy silane, an elastomeric coating, can be obtained.

The information in US Patent A 3 360 491 is similar to the information in 20 US Patent A 3 294 725 except that the dodecylbenzenesulfonic acid is replaced by hydrogenolauryl sulfate.

U.S. Patent No. 3,355,406 discloses, inter alia, a silicone latex comprising: 25 - an aqueous colloidal suspension of an a, u) - (dihydroxy) polydiorganosiloxane, - a filler necessarily comprising a silsesquioxane in the form of a colloidal suspension - a catalyst selected from inorganic acids, strong bases, dialkyltin diacylates and organic or inorganic peroxides.

U.S. Patent No. 3,697,469 discloses a particular method for emulsion polymerization of polydiorganosiloxanes and the possibility of adding colloidal silica and tin salt to this emulsion to obtain an elastomeric coating by evaporation of water is mentioned.

French Patent Specification A 2 110 358 discloses a pH 5 silicone emulsion between 6.5 and 9, which is crosslinkable to an elastomer having conductivity for electricity, after evaporation of water by incorporation of so-called carbon black. The emulsion, further comprising tin salt and a polyalkoxy silane, is not stable during storage and should be stored in two separate packages (two-component emulsion).

In United States Patent Nos. A 4,221,688 and A 4,244,849, as well as in French Patent No. A2,463,163, silicone emulsions which are stable during storage and which include: 15 - an emulsion of an a, u) are mentioned. - (dihydroxy) polydiorganosiloxane polymer which is anionically stabilized, - a silicon-containing filler, 20 - a tin salt, - optionally a non-reinforcing filler.

The siliceous filler may be a colloidal silica (US PS A 4 221 25 688), sodium silicate (US PS A 4 244 849) or an amorphous silica in powder form (French Patent No. A 2,463,163).

It is stated in these three above-mentioned patents in relation to the prior art aqueous emulsions, on the one hand, that in order to obtain a monocomponent emulsion which is stable during storage, it is necessary to maintain the emulsion at an alkaline pH greater than 8.5 or equal, preferably greater than 10, and, on the other hand, to incorporate in the emulsion a tin salt to shorten for a few days the maturation step of the emulsion required to obtain a dispersion which is capable of being cross-linked.

The known filler silicone emulsions preserved at pH 5 which are acidic or neutral exhibit at least one of the disadvantages mentioned below - they are not stable during storage when packed in a single package (monocomponent preparation), 10 - they exhibit too long a curing time for an elastomer, - they are not thixotropic, 15 - they are only very weakly adhered to the usual carrier materials.

Aqueous emulsions or dispersions based on silicone resins which can be crosslinked to an elastomer by elimination of the water have been previously described.

U.S. Pat. No. 3,355,406, which has already been disclosed, discloses a silicone latex consisting of an α, (io- (dihydroxy) polydiorganosiloxane, preferably produced by emulsion polymerization) and a silsesquioxane synthetic resin composed of the repeating groups RS 10 5 (R is a hydrocarbon group) The latex may further comprise a metallic catalyst for curing and an alkyltrial coxysilane.

Document US-A-3,075,560 discloses the use of hydroxylated siloxanes and a boron compound to reduce bonding between a diorganopolyoxylanes-silicon mixture 30.

In EP-A-143877 and in U.S. Patent No. A-4,554,187, it is disclosed that the silicone synthetic resin, which is combined with a, u> - (dihydroxy) - 4 polydiorganosiloxane, is a low molecular weight reactive resin, which exhibits alkoxy groups or acyloxy groups.

EP-A-202 494 describes the use of epoxy function silanes as agents for the coupling in an emulsion based on dihydroxypolyorganosiloxanes and colloidal silica or alkaline silica which have been subjected to a ripening at pH 9-12, in European Patent Application No. EP-A-266 729 discloses that the silicone synthetic resin combined with the α, ω - (dihydroxy) polydiorganosiloxane and with the curing catalyst is a siliconate.

For this siliconate may be combined a silicone resin comprising up to 10% by weight of hydroxyl groups.

In EP-A-304 719, published March 1, 1989, it is disclosed to use in place of the siliconate a high molecular weight silicone resin which is insoluble in toluene and which is in the form of an aqueous emulsion if it is in cell size is greater than 200 nanometers. In the following, unless otherwise stated, the percentages and percentages are by weight.

It is an object of the present invention to provide an aqueous dispersion (emulsion) of silicone having an acidic or basic pH which can be crosslinked to an elastomer by elimination of water at ambient temperature and which does not exhibit the disadvantages attached to the known emulsions or in a very dilute form.

Another object of the present invention is to provide an aqueous silicone dispersion of the above type, which is stable during storage, and correctly and sufficiently cross-links to an elastomer by elimination of the water at ambient temperature, forming elastomers 5, 175833 B1. retains its mechanical properties during its aging, and another object of the present invention is to provide an aqueous silicon dispersion of the above-mentioned type in which the ripening step can be carried out at a slightly elevated temperature (20-50 ° C) and during of a time-period less than 48 hours.

Another object of the present invention is to provide an aqueous silicone dispersion of the type described above which leads to an elastomer which further exhibits an improved flame resistance.

10

Another object of the present invention is to provide an aqueous silicone dispersion of the above-mentioned type which leads to an elastomer which exhibits a sufficiently good adhesion on various substrates, particularly on glass, concrete and metals (steel, aluminum).

15

These objects and others are achieved by the present invention which relates to aqueous silicone-based dispersions which can be crosslinked to an elastomer by elimination of water at ambient conditions, which dispersions in parts by weight comprise: 20 (A) - 100 parts by weight of an emulsion of the oil-in-water type of an α, ω - (dihydroxy) - polysiloxane stabilized with at least one surfactant selected from anionic and nonionic agents and mixtures thereof; (B) -1-100 parts by weight of a hydroxylated silicone resin, (C) - 0-250 parts by weight of non-silicon-inorganic filler; (D) - 0.01-3 parts by weight of a metallic curing catalytic compound, and excludes the presence of a silicon compound similar to Formula 30m'-Si (0'M + WOH) 3.m and / or condensation products formed by the removal of water in which Formula 5 R '- represents groups of hydrocarbons - identical or different - consisting of 1-18 C atoms and which can carry halogen atoms, amino groups, ether groups, ester groups, epoxy groups, mercapto groups, cyano groups or groups of (poly) glycols, the last 10 of which are made up of units of oxy-ethylene and / or oxy-propylene, m - is an integer or real number between 0.1 and 3, and M - represents an alkali metal ion, an ammonium group or a phosphonium group.

The dispersion has a solids content of at least 40% and is characterized in that a solution of at least 70% by weight of the hydroxylated silicone resin (B) in toluene can be formed and that (B) per molecule exhibits at least 2 different units selected from those having the formulas: RsSiOo.s. R2S10, RS104 and S102, the groups R, which may be identical or different, are selected from vinyl, phenyl, 3,3,3-trifluoropropyl and linear or branched C1-C6 alkyl groups. Furthermore, this synthetic resin has a weight content of hydroxyl groups between 0.1 and 10%.

The incoming α, u) - (dihydroxy) polydiorganosiloxanes should have a viscosity 25 of at least 100 mPa x s at 25 ° C, preferably of at least 50000 mPa x s.

Indeed, for viscosities greater than 50000 mPa x s, an elastomer is obtained which exhibits an overall system of appropriate mechanical properties, especially with respect to Shore A hardness and fracture elongation.

30

Further, the higher the viscosity, the better the mechanical properties are maintained during the aging of the elastomer.

7 DK 175833 B1

Preferred viscosities for the present invention are between 50000 and 1500000 mPa x s at 25 ° C.

The organic groups of α, C 1- (dihydroxy) polydiorganopolysiloxanes are monovalent hydrocarbon groups containing up to 6 carbon atoms, optionally substituted with cyano groups or fluorine groups. The substituents commonly used because of their availability among the industrial products are the groups: methyl, ethyl, propyl, phenyl, vinyl and 3,3,3-trifluoropropyl. Generally, at least 80% by number of these groups is 10 methyl groups.

It is particularly preferred within the scope of the present invention to use α, ω - (dihydroxy) polydiorganosiloxanes prepared by the anionic polymerization process disclosed in the above-mentioned 15 United States Patent Nos. A 2,891,920 and especially A 3,294,725 (cited for reference). The polymer obtained is stabilized anionically with a surfactant, which, in accordance with United States Patent Specification No. 3,294,725, is preferably an alkali metal salt of an aromatic hydrocarbon sulfonic acid, the free acid also playing the role of polymerization catalyst.

The preferred catalyst and preferred surfactant are dodecylbenzenesulfonic acid and alkali metal salts thereof, especially the sodium salt thereof. Optionally, other anionic or nonionic surfactants may be added. However, such an addition is not necessary, since the amount of the surfactant resulting from the neutralization of the sulfonic acid, as stated in U.S. Patent No. 3,294,725, is sufficiently large to stabilize the emulsion of the polymer. This amount is generally less than 3%, preferably less than 1.5% by weight of the emulsion.

This method of emulsion polymerization is particularly interesting as it allows the emulsion (A) to be obtained directly. This process also makes it possible to obtain without difficulty emulsions (A) of α, ω - (dihydroxy) polydiorganosiloxane with very high viscosity.

In order to prepare the emulsion (A), one may also proceed from already polymerized α, ω - (dihydroxy) polydiorganosiloxane and then bring it into aqueous emulsion, stabilizing the emulsions with an anionic and / or nonionic surfactant according to the invention. a method well known to those skilled in the art and described in detail in the literature (see, for example, French Patent Nos. A 2 064 563, A 2 094 322, and A 2 114 230 and EP-A-169 10 098 ).

According to this method, the polymers of α, ω - (dihydroxy) polydiorganosiloxane are mixed with an anionic or nonionic surfactant by simple stirring, the latter being in aqueous solution and then adding water and then converting it. the overall system for a fine and homogeneous emulsion when passing through a classic colloid mill.

The resulting milled material is then diluted with an appropriate amount of water, thus obtaining an emulsion (A) which is stabilized with an anionic or nonionic surfactant and which is stable! during storage.

The amount of anionic or nonionic surfactant to be used is the one most frequently used to initiate the emulsion formation process, especially those disclosed in the aforementioned patents and in U.S. Patent No. A-2,891. 920th

The anionic surfactants preferred in the field of the present invention are the alkali metal salt of an aromatic hydrocarbon sulfonic acid, and the preferred nonionic surfactants are polyoxyethylated alkylphenols. These nonionic surfactants are, of course, the same as those optionally added to the emulsions (A) obtained by emulsion polymerization, as stated above.

The emulsion (A) prepared by emulsion polymerization or by immersing the silicone polymer is in the form of an oil-in-water emulsion and preferably has a dry matter content greater than 45% by weight.

Incorporation per 100 parts of emulsion (A) 1-100, preferably 2-20 parts, calculated as dry matter, of a hydroxylated silicone resin (B).

10

The hydroxylated silicone resin (B) has a weight content of hydroxyl groups between 0.1 and 10%, preferably between 1 and 6%.

This synthetic resin (B) exhibits per. molecule at least two different units selected from those having the formulas R3 SiO0.5 (unit M), R2SiO (unit D), RSi01i5 (unit T) and SiO2 (unit Q).

Examples of the alkyl group R groups are: methyl, ethyl, isopropyl, tertiobutyl and n-hexyl.

20

These silicone resins are branched organopolysiloxane polymers which are well known in the art and which are described in numerous patents.

25 Examples of ordinary art resins, the MQ resins, the MDQ resins, the TD resins and the MDT resins can be cited.

Resins which are solid or liquid at ambient temperature can be used. These resins may be incorporated into the aqueous emulsions as they exist, in solution in an organic solvent or a silicone oil or also in the form of aqueous emulsions.

DK 175833 B1 10

Aqueous emulsions of silicone resins which are useful are e.g. disclosed in U.S. Patent Nos. A 4,028,339, A4,052,331, A4,056,492, A4,525,502, and A4,717,599, which are cited for reference.

Another component of the dispersion according to the invention is the addition of 0-250, preferably 5-200 parts of a non-silicon-containing inorganic filler which may be partially reinforcing or simply as filler (C).

The fillers (C) have a base size distribution which is generally between 1 and 300 µm, and a BET surface area of less than 50 m 2 / g.

Examples of fillers (C) useful alone or in admixture are carbon black, titanium dioxide, alumina, hydrated alumina, expanded vermiculite, non-expanded vermiculite, calcium carbonate, zinc oxide, mica, talc, iron oxide, barium sulphate and soda lime.

These fillers (C) are introduced into the emulsion (A) in the form of a dry powder, e.g. by simple mixing.

According to a variant of the invention, it has been found that if the filler (C) consists mainly of only a filler selected from hydrated alumina, expanded vermiculite, non-expanded vermiculite having a content of 5-250, preferably 50-200 parts per 100 parts of the emulsion (A), an elastomer having a particularly high resistance to flames is obtained and 25 which is not obtainable with the above other categories of fillers (C), especially with non-hydrated alumina. Ceramic fibers or aramid may also be incorporated according to one disclosed in EP-A-212 827.

The metallic catalytic compounds for curing (D) are mainly salts of carboxylic acid and halides of metals selected from lead, zinc, zirconium, titanium, iron, tin, baryum, calcium and manganese.

11 DK 175833 B1

The component (D) is preferably a catalytic tin compound, generally an organotin salt, which is preferably introduced in the form of an aqueous emulsion. The useful organotin salts are described in particular in the work of NOLL, Chemistry and Technology of Silicones Academic Press (1968), page 337.

5

One can also mention as the catalytic tin compound the reaction product between a tin salt, especially a tin di-carboxylate and ethyl polysilicate, as disclosed in U.S. Patent No. 3,862,919.

The reaction product can also be used between an alkyl silicate or an alkyl trialkoxysylane and debutyltin diacetate, as described in Belgian Patent No. A 842,305.

The preferred tin salts are tin bischelates (EP-A-147,323 and EP-A-235,049), diorganotin dicarboxylates and especially dibutyl or dioctyltin divercetates (British Patent Specification A 1,289,900), dibutyl or dioctyltin diacetate, dibutyl or dioctyltin dilaurate. 0.01-3, preferably 0.05-2 parts of organotin salt per ml are used. 100 parts of (A).

In accordance with one variant, one can further incorporate per. 100 parts of the emulsion (A) is a silica-containing additive (E) selected from sodium silicate (0.03-30 parts) and a silicon-containing filler with reinforcing properties or with partially reinforcing properties (1-150 parts).

These silicon-containing fillers are selected from colloidal silica, combustion silica powders and precipitated silica, or a mixture thereof. Combustion silica is preferred. However, silicone-containing partially reinforcing fillers, such as diatomaceous earths or ground quartz, may also be used.

The sum of the proportions of (C) + (E) should per 100 parts of the emulsion (A) be less than 300 parts.

30 12 DK 175833 B1

The combustion silica and precipitating silica powders are well known, they are especially used as fillers in silicone elastomeric compositions which are vulcanizable in hot state to form a silicone rubber. These powders exhibit an average particle size generally less than 5 0.01 µm and a specific BET surface area greater than 50 m 2 / g, preferably 150-300 m 2 / g.

Incorporation into the emulsion (A) of this silicon-containing additive (E) by any suitable method, especially by stirring, greatly increases the viscosity of the emulsion (A), which then exhibits a paste-like character.

Indeed, it has been found in accordance with the present invention that the addition of this silicon-containing additive (E) is sufficient to transfer to the dispersion a so-called "thixotropic" character which is more or less pronounced. The emulsion which e.g. is removed from a storage package, adheres without running on a carrier layer, even if it is vertical, and cures to an elastomer by evaporating the water at ambient temperature. One can also obtain a non-running emulsion using as filler (C) of calcium carbonate, whose particle diameter is less than 0.1 µm. Of course, a slight heating of the composition (to about 40-80 ° C) to accelerate evaporation of the water is not excluded within the scope of the invention.

Various additives may be added to the dispersions of the present invention which allow the properties of the emulsions and of the elastomers formed on the basis of the emulsions to be eliminated by modification of the water. Adhesive promoters (F), preferably organotrialkoxysilanes, such as e.g. γ-aminopropyl triethoxysilane, N (aminoethyl) γ-aminopropyl trimethoxysilane, vinyl trimethoxysilane, alkyl silicates such as methyl silicate or ethyl silicate or their partial hydrolysis product, i.e. alkyl polysilicates such as methyl polysilicate and ethyl polysilicate in an amount of 0.01-20 parts of adhesive per 100 parts emulsion (A).

in DK 175833 B1 13

The organotrialkoxysilanes and the alkyl silicates preferably correspond to a general formula: R'aSi (OR) 4.a 5 wherein R is an alkyl group containing 1-4 atoms, R 'is R or vinyl, γ-aminopropyl, N (aminoethyl) γ-aminopropyl, and a is 1 or 0.

The dispersions of the present invention have a pH value which is generally between 4 and 13. This value depends on the nature of the constituents contained in the dispersion, especially with respect to the surfactant and the catalyst for the emulsion (A). , as well as with respect to the filler (C).

Depending on the intended applications, it is possible to prepare dispersions having a pH between 4 and 7 by the addition of an inorganic or organic acid, preferably an oxygen-containing boundary derivative, and dispersions having a pH between 7 and 13 with addition. of an inorganic or organic base, as described in more detail below.

One can cite as other examples of additives anti-fungal agents, anti-foaming agents, as well as thixotropic regulators such as carboxymethyl cellulose, xanthan gum and polyvinyl alcohol.

The dispersions according to the invention are particularly suitable in the construction industry for the production of sealants and of sealants for joints.

The dispersions of the present invention can be prepared as follows:

An emulsion (A) is prepared either by the emulsion polymerization process and an emulsion is disposed which is stabilized with an anionic and optionally nonionic surfactant or by the method of to bring into emulsion α, ω- (dihydroxy) polydiorganosiloxane, and one has at its disposal an emulsion stabilized with an anionic and / or nonionic surfactant. ! 5

In order to prepare the dispersions of the invention, it is recommended to add at ambient temperature to the emulsion (A), initially the metallic cure catalytic compound (D), preferably in the form of an aqueous emulsion, upon which the pH of the mixture is adjusted to a value greater than 7 and generally less than 13 by means of an inorganic or organic base, preferably by means of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, or to a value less than 7 and greater than 4 by the addition of a suitable amount of oxygen-containing border derivative selected from boric oxide, boric acids and borates.

15

Primary amines such as diethylamine can be used as an organic base.

However, in accordance with a preferred embodiment of the invention, the pH is adjusted by a suitable amount of an inorganic base introduced in the form of an aqueous solution, preferably selected from the solutions of alkali metal hydroxides and alkaline earth metal hydroxides such as sodium hydroxide, potassium hydroxide, solutions of calcium hydroxide, baryum hydroxide and of magnesium hydroxide. However, these alkaline earth metal hydroxides can also be introduced directly in the form of solids.

The boron oxide is also known by the name boric anhydride. As boric acid, mention may be made of orthoboric acid, metaboric acid and tetraboric acid. As borates, the triorgano borates and the inorganic borates are useful. Triethylborate, triphenylborate, tribenzylborate, tricyclohexylborate, trismethylsilylborate, tri (t-butyljborate, diammonium tetraborate, ammonium pentaborate, sodium tetraborate, decahydrate (borax), use partial hydrolysis products of these rates.

DK 175833 B1 15

By adjusting the final pH of the dispersion to a value between 4 and 7, it is generally sufficient to add to the dispersion 0.01-5 parts of one oxygen nanoigi uoruerivai per liter. iuu utrie aremuisionen ρλ ;.

The fillers (C) and, optionally (E), the resin (B) as it is added, or in solution in an organic solvent, or in a silicone oil, or also in the form of an aqueous emulsion are added.

As a silicone oil, a block-trimethylsilyl-polydimethylsiloxane 10 having a viscosity at 25 ° C between 100 and 5000 mPa x s can be used.

The final emulsion obtained is then homogenized and degassed, then filled onto packaging which is close to oxygen from the air and to water vapor.

15

Components (A), (B), (C), (D) and optionally (E) and (F) are mixed in such quantities that the final emulsion exhibits a dry matter content higher than 40%, preferably higher than 60%, but in generally lower than 90%.

The dispersions of the present invention can be used as paints which are crosslinkable in thin layers. They then preferably exhibit a solids content of between 40 and 70%.

To determine the content of dry matter, 2 g of the dispersion is placed in an aluminum weighing dish and heated for one hour at 150 ° C in an oven with air circulation. After cooling, the weighing dish is re-weighed and the percentage of residual material is determined from the 2 g originally placed, which reflects the dry matter content.

According to a preferred variant, the dispersion according to the invention undergoes, after its preparation, a ripening step at ambient temperature or at a temperature between 20 and 90 ° C for a duration of a few hours to a few days.

16 DK 175833 B1

This maturation step simply consists in optionally heating and allowing the dispersion to be left in the absence of oxygen from the air before being brought into use.

In the following or in the foregoing, the percentages and percentages, unless otherwise stated, are by weight.

Example 1

Preparation of the emulsion (A): 10

It is obtained by emulsion polymerization of an α, ω (dihydroxy) polydiorganosiloxane oil having a viscosity of 100 mPa x s at 25 ° C in the presence of dodecybenzenesulfonic acid.

When the viscosity of the oil reaches 106 mPa x s at 25 ° C, the polymerization is stopped by neutralization of the catalyst.

The obtained emulsion (A) has a solids content of 59%.

Add 100 parts of the emulsion (A) with stirring 1.5 parts of aqueous emulsion (D) containing 37% by weight of dioctyl-tin dilaurate. Then 1.2 parts of diethylamine and 60 parts of filler (C), which is CaCO 3 of precipitated origin, having an average grain size of 0.07 µm are added.

To the emulsion obtained, 8.3 parts of a hydroxylated silicone resin (B) soluble in toluene having a weight% of hydroxyl groups and consisting of 2% by weight of the repeat group CH3 SiO155 are added. 61.5% by weight of the repeat group (CH3) 2 SiO and 36.5% by weight of the repeat group (CH3) 3 SiOo, 5 having the molecular weight 4000 and having a ratio R / Si = 1.77.

The final dispersion obtained has a pH of 9.5.

17 DK 175833 B1 '

It is homogenized for 30 minutes and then bottled on a package which

is close to the oxygen of the air and to water vapor. IN

After 4 days of storage, use a knife to disperse the dispersion referred to in the following, to form a thin skin layer (foil) of 2 mm thickness, which is allowed to dry for 7 days at ambient temperature.

The dried values are measured on the average values resulting from certain mechanical properties: 10 - Shore A hardness (DSA) according to standard ASTM-D-2240, i - breaking strength (R / R) according to standard AFNOR-T 46 002 corresponding to standard in ASTM -D 412 and expressed in MPa, 15 - the elongation at break (A / R) as a percentage in accordance with the standard AFNOR-T 46 002, - the modulus of elasticity (ME) at 100% extension in accordance with the standard AFNOR-T 46 002 and expressed in MPa.

The mechanical properties thus obtained are summarized in subsequent Table 1.

Examples 2-3

Exactly the procedure of Example 1 is repeated except that the 8.3 parts of artificial resin (B) are replaced by: 30 - for example 2: 8.8 parts introduced as they are of an artificial resin soluble in toluene and in xylene, which has 2.2 wt% hydroxyl groups and consists of 70 wt% of the repeating groups CH3 SiOi-5 and 30 wt% of the repeating group (CH3) 2 SiO of molecular weight 1300 and having a ratio R / Si = 1. The final emulsion obtained has a pH of 8.5.

for example, 3: 4.1 part introduced in the form of a 70 wt% solution toluene of 5 an artificial resin having 2.2 wt% hydroxyl groups and consisting of 73 wt% repeating groups C6H5SiOi.5 and 27 wt. -% repeat groups (CH 3) 2 SiO, having a ratio R / Si = 1.4. The final emulsion obtained has a pH value of 8.5.

10 The mechanical properties are summarized in subsequent Table 1.

Table 1

Examples 12 3 PSA (Shore A Hardness) __ 13__16__10_ R / R (MPa) __ T27__T36__1.38 A / R (%) __ 1021__1020__1306 ME (MPa) 0.17 0.20 0.12 Example 4-6

Exactly the procedure of Example 1 is repeated except that the 1.2 parts of diethylamine are replaced by: 20 - for example 4: 4 parts of an aqueous 20% potassium hydroxide solution. The partial emulsion exhibits a pH of 11.

for example, 5: 4 parts of a solution of 20% potassium hydroxide and 0.5 parts of ethyl polysilicate (ethyl silicate 40®). The pH is 11.

25 - for example, 6: 4 parts of a 20% potassium hydroxide solution and 1 part of ethyl polysilicate. The pH is 11.

19 DK 175833 B1

A belt of 4 mm thickness is deposited on a glass or concrete support.

After 10 days, the adhesion of the elastomer formed is assessed by manually pulling the tape.

5 The adhesions were quality bedded in 3 ways: - good adhesion when the tape cannot be loosened in the adhesive from its support layer (notation ++), 10 - medium adhesion when the tape is difficult to remove in the adhesive and has small surfaces (notation +), - lack of adhesion when the tape is easily loosened in its bond (notation 0).

15 The mechanical properties obtained and the ratings of the adhesion are summarized in subsequent Table 2.

Table 2

Examples 4 5 6 PSA (Shore A Hardness) __ 15__23__27_ RIR (MPa) __ V76__1 ^ 2__1.67 A / R (%) __ 986__730__704 ME (MPa) __ 019__029__0.45

Attachment glass __ + __ ++ _ ++

Attachment of concrete + + + 20

Example 7

Repeat the procedure of Example 1 except substituting: 25 8 DK 175833 B1 - the 8.8 parts of the MDT resin MDT with 7 parts of an artificial resin MQ in solution in toluene and containing 2% by weight hydroxyl, and which consists of 50% by weight of repeat groups M and 50% by weight of repeat groups Q, and having a molecular weight of 10000 and a value of the ratio R / Si = 1.3, as well as 5 - 1.2 parts of diethylamine per liter. 4 parts of a 20% potassium hydroxide solution.

The mechanical properties obtained and the assessment of the adhesion are summarized in subsequent Table 3.

10

Example 8

The procedure described in Example 7 is repeated and an additional 1 part of ethyl polysilicate (ethylsilicate 40®) is added.

15

The mechanical properties obtained and the assessment of the adhesion are summarized in subsequent Table 3.

Example 9 20

Exactly the procedure of Example 2 is repeated except: a) - the 1.2 parts diethylamine is replaced by 0.59 parts boric acid, 25 b) - the 1.5 parts catalyst emulsion (D) is replaced by 1.5 parts of a catalyzing emulsion containing 37% by weight of a tin compound which is the reaction product between 1 mole of dioctyltin oxide and 1 mole of versatinic acid® with elimination of the water formed, c) - a ripening step of the duration is carried out for 2 hours and 30 minutes at 80 ° C before dispensing the dispersion in a tight package.

DK 175833 B1 21

The mechanical properties obtained are summarized in subsequent Table 3.

Table 3

Examples 7 8 9 PSA (Shore A Hardness) __ 7__13__16_ RIR__09__036__1.04 A / R__1377__680__1010 ME__0J5__0.2 0.19

Attachment glass ++ ++

Attachment Concrete __ + __ ++ __-_ 5

Claims (8)

Aqueous silicone-based dispersions which can be crosslinked to an elastomer by elimination of water at ambient conditions, comprising in parts by weight: (A) - 100 parts by weight of an oil-in-water emulsion of an α, ω - (dihydroxy) - polysiloxane stabilized with at least one surfactant selected from anionic and nonionic agents and mixtures thereof; (B) -1-100 parts by weight of a hydroxylated silicone resin, (C) - 0-250 parts by weight of non-silicon inorganic filler; (D) - 0.01-3 parts by weight of a metallic curing catalytic compound; this dispersion having a solids content of at least 40%. characterized in that a solution of at least 70% by weight of the hydroxylated silicone resin (B) in toluene can be formed and molecule exhibits at least 2 different moieties selected from those having the formulas: R3 SiOo, 5, R2S10, RSiO-i and S1O2, the groups R, which may be identical or different, selected from vinyl, phenyl, 3,3,3 trifluoropropyl and linear or branched C1-C6 alkyl groups, this resin having a weight content of hydroxyl groups between 0.1 and 10%, and excluding the presence of a silicon compound corresponding to the formula R'-Si (0'M +) m ( OH) 3.m 30 and / or condensation products formed by the removal of water in which Formula R '- represents groups of hydrocarbons - identical or different, containing 1-18 C atoms and which can carry halogen atoms, amino groups, ether groups, ester groups, epoxy groups · mercapo groups, cyano groups or groups of (poly) glycols, the latter of which are made up of units of oxy-ethylene and / or oxy-propylene, 5 m - is an integer or real number between 0.1 and 3, and M - represents an alkali metal ion , an ammonium group or a phosphonium group. Aqueous dispersion according to claim 1, characterized in that the metallic compound (D) is an organotin salt, wherein (D) is in the form of an aqueous emulsion. Aqueous silicone dispersion according to any one of claims 1-2, characterized in that the emulsion (A) has a solids content of at least 45% by weight. ! 15 | Aqueous silicone dispersion according to any one of the preceding claims, characterized in that it comprises 5-200 parts by weight of filler (C) selected from: hydrated alumina, alumina, calcium carbonate, expanded vericulite, non-expanded vermiculite, carbon black, zinc oxide, titanium dioxide, gums, talc, iron oxide, barium sulfate and slaked lime. Aqueous silicone dispersion according to claim 4, characterized in that the incoming calcium carbonate has an average particle diameter less than 0.1 µm. 25 Aqueous silicone dispersion according to any one of the preceding claims, characterized in that it comprises: (A): 100 parts oil-in-water emulsion of an α, co- (dihydroxy) polydiorganosiloxane having a viscosity at 25 ° C between 50,000 and 1,500,000 mPa's stabilized with a surfactant selected from an alkali metal salt of an aromatic hydrocarbon sulfonic acid and polyoxyethylenated alkyl phenols, DK 175833 B1 (B): 2-20 parts hydroxylated silicone resin, (C): 50-200 parts of an inorganic filler, and 5 (D): 0.05-2 parts of a diorganotin dicarboxylate, said emulsion having a solids content of at least 60%. Aqueous silicone dispersion according to any one of the preceding claims, characterized in that it further comprises per unit weight. 100 parts of an emulsion (A) a silicon containing additive selected from sodium silicate (0.3-30 parts), and a silicon containing or partially reinforcing filler (1-150 parts), with the proviso that the sum of the parts ( C) + (E) pr. 100 parts of (A) is less than 300 parts. 15 Aqueous dispersion according to any one of the preceding claims, characterized in that they further comprise 0.01-20 parts of an adhesive (F) selected from organotrialkoxysilanes, alkyl silicates and alkyl polysilicates.