UA72510C2 - Silicate material, a method for producing thereof and a method for making coating from silicate material - Google Patents

Abstract

The invention relates to a silicate material which contains an amorphous binding matrix, consisting of at least an alkali oxide and a silicon dioxide, whereby the alkali oxide is lithium, sodium and/or potassium oxide. In order to produce a weather-resistant, acid-resistant and temperature-resistant silicate material, both for shaped bodies and for coatings that can be produced from a silicate mixture whose characteristics remain stable and are not adversely affected during a storage period of at least three months in a scaled container, the following is recommended: The amorphous binding matrix should contain more than 25 mol silicon dioxide per mol of alkali oxide, in addition to between 10 g and 150 g of a bound, water-repelling additive which contains silicon per 1000 g silicon oxide with a uniform dispersion and between 400 g and 7000 g of a filler, whose panicle thickness is less than 200 m. Hydroxy functional alkylpolysiloxane with a high proportion of linear siloxane chains and a low to medium degree of branching is recommended as the water-repelling additive.

Description

of the molded product, as well as for covering the substrate, which would be resistant to the effects of weather, in particular transitions from freezing to thawing, as well as to the effects of acids. The coating must be applied in a simple way and harden at temperatures below 100"C. The silicate mixture intended for the production of silicate mass must be stored in a closed container for at least three months without damaging its properties.

According to the invention, the problem is solved by the fact that the amorphous binder matrix for each mole of alkali metal oxide contains more than 25 moles of silicon dioxide, and that, in addition, the binder matrix for every 1000g of silicon dioxide contains from 10 to 150g uniformly of a silicon-containing hydrophobic additive, and that, in addition, the silicate mass for every 1000g of silicon dioxide contains from 400 to 7000g of aggregate with particles less than 200nm thick.

The term alkali metal oxide is used herein to refer to oxides obtained by silicate analysis of conventional metal content data even when the metal is actually present in a chemical compound such as a silicate or similar.

The binding matrix has a very significant content of silicon dioxide, namely more than 25 mol of silicon dioxide per mol of alkali metal, preferably from 50 to 500 mol of silicon dioxide per mol of alkali metal.

Therefore, the invented silicate mass is very resistant to the effects mentioned in the task, and at the same time, it is suitable for application to the substrate in the form of an aqueous silicate mixture. Due to the low content of alkali metals, the silicate mixture intended for the production of silicate mass can be stably stored in a packed container for six months or more without harming its properties. When water is added, the silicate mixture hardens already at room temperature, turning into a hydrophobic solid silicate mass, without the need for the use of chemical hardeners. The latter, however, can be used when very fast hardening is required.

Addition of hydrophobic additives, even in small quantities, causes a sharp decrease in water absorption by the hardened silicate mass, improvement of weather resistance, very good binding of the aggregate, and, if necessary, pigments, in the hardened silicate mass. When applying the chalking sample used in painting, namely when wiping the outer surface with a cloth, even after exposure to adverse weather, no traces of pigment or filler were found on the cloth. Due to the low content of hydrophobic impurities, 51O2 always forms a continuous phase in the binding matrix.

It is advantageous that silicon-containing hydrophobic additives have hydrophobic reactive groups that enable binding of the binding matrix. First of all, it is recommended to use polysiloxane.

Polysiloxanes bind very strongly and for a long time to the binding matrix if they have reactive groups. Alkyl polysiloxanes with alkoxy- and/or hydroxy functional groups are extremely suitable.

The beneficial results described above can be achieved more successfully if the polysiloxane has mainly linear siloxane units with low or medium branching. Whereas purely linear polysiloxanes have oily and highly branched siloxanes with a hard resinous and brittle consistency, polysiloxanes are extremely suitable due to their high flexibility.

By adding different aggregates, the silicate mass can be best adapted to different needs. Due to the use of fine-grained aggregate, only very small cavities are formed between the particles of the aggregate, which are filled with a binder. Therefore, there are no cracks in the silicate mass. It is advisable that the thickness of the aggregate particles is less than 40 nm. The thickness of spherical and fibrous particles means their diameter.

Silicate mass is exceptionally resistant to the effects of acids, if the aggregate is acid-resistant. Among the crystalline aggregates, quartz or silicate is preferred, and among the amorphous aggregates, glass flour is preferred.

It is clear that mixtures of various crystalline and/or amorphous substances can be used as an aggregate.

By selecting the appropriate aggregate, the coefficient of thermal expansion of the coating obtained from hardened silicate mass can be adjusted to the coefficient of thermal expansion of the substrate, as a result of which no thermal cracks are formed in the coating.

An exclusively crack-free silicate mass with a smooth outer surface is obtained when the binding matrix contains a crystalline filler from the class of silicates. The aggregate can, for example, consist of mica, or a mixture of various silicates.

Silicate mass has an exceptionally high tensile strength if it has a fibrous aggregate.

To give it the desired color, the silicate mass can be colored with colored dyes. Mineral pigments such as iron oxide or titanium oxide are suitable as dyes. It is clear that colored aggregates, in particular colored glass powders, can be used for coloring. Organic dyes such as phthalocyanine, quinacridone or the like can also be used if they are introduced according to (German Pat.

OE-S 195 33 0811.

Next, the most expedient method of manufacturing silicate mass according to the invention is described.

For the production of silicate mass, an aqueous silicate mixture is used, which subsequently hardens. The aqueous silicate mixture can contain an alkaline silicon sol with more than 25 mol of silicon dioxide per mol of alkali metal oxide, with a silicon dioxide content in the range between 15 and b5wg.9o, more expediently from 30 to bOwg.9Uo, and also from 10 to 150g of binding silicon-containing hydrophobic additive, evenly distributed over 1000g of silicon dioxide to build an amorphous binding matrix, and from 400 to 7000g of aggregate with a thickness of less than 200nm per 1000g of silicon dioxide.

It was established that in order to prevent delamination of the aqueous silicate mixture, the pH value of the silicon sol must be adjusted to the content of the hydrophobic admixture. With a low content of hydrophobic impurities, you can use silicon sol with 500 mol of silicon dioxide per mol of alkali metal. With a higher content of hydrophobic impurity, the content of alkali metal oxide can be higher.

It is expedient that the specific external surface (VET) of the silicon sol particles averages from 35 to bOm2/g, preferably from 50 to 300m?/g. The specific external surface (VET) value is especially appropriate

160m2/h,

Silica sol with particles divided depending on their size into two parts is exclusively suitable.

An exceptionally weather-resistant silicate mass is obtained from this ash.

A bimodal silicon sol was found to be suitable, in which approximately 40 to 80wg.9o particles have a specific external surface (VET) in the range between 30 and 100mg/g, and approximately 20 to bOwg.95 particles have a specific external surface (VET) in the interval between 200 and b00m"/g. The most suitable is a bimodal silica sol, in which approximately bowag.9o particles have a specific external surface (SPE) equal to 50m2/g, and approximately 4Owag.95 particles have a specific external surface (SPE), which is equal to Z00m2/h.

For the production of colored silicate mass, the aqueous silicate mixture may contain dyes.

Inorganic dyes can be directly introduced into the wool silicate mixture.

It is possible to dye with organic dyes, such as phthalocyanine, quinacridone, or the like, if the organic dye is introduced into the aqueous silicate mass dispersed in an aqueous polymer dispersion suitable for the silicate mixture. As a polymer dispersion, an aqueous polymer dispersion based on styrene and/or polyacrylate is particularly suitable. The weight ratio of the organic dye to the polymer should not exceed 1. As a result of bonding with the polymer dispersion, the organic dye is fixed in the matrix for a long time.

Silicate mass can be used as a surface coating, for example as a weather-resistant protective layer, if the water silicate mixture described above is applied to the substrate and dried. The coating has a porosity of less than 20905.

Applying an aqueous silicate mixture to cover the substrate can be done with a brush, roller, pouring, dipping, or most expediently, spraying. Optimum technological properties can be achieved by adding common additives present on the market, such as thickeners, dispersants, foaming agents and/or wetting agents. During subsequent drying, the water silicate mixture solidifies to form a coating of silicate mass. The substrate can be, for example, metal, fresh concrete, or a harder mineral base such as hardened concrete or plaster.

The substrate can be roof tiles. Due to the relatively low temperatures of manufacturing silicate mass, Yuna is particularly suitable for covering concrete roofing stone. The thickness of the coating can be on average from 20 nm to 2 mm, the most expedient is 0.1 mm.

The silicate mass produced in accordance with the invention is exceptionally well suited for coating granulate, sand, or aggregates for decorative purposes.

Silicate mass is suitable not only for coatings, but also for many applications for which other materials are currently used, such as for filling and sealing gaps, or for bonding building materials. It turned out that the silicate mass produced according to the invention, which had fireclay flour as a filler, was able to replace the putty widely used until now, which was used to fill the internal joints of chimneys. Here, above all, the high temperature resistance and good acid resistance of the hardened silicate mass turned out to be extremely useful. The experiment unexpectedly showed that even after the chimney burned out, during which the temperature can reach 1100C, the density and strength of the joints remained guaranteed. For such applications, silicate masses should have a small content of hydrophobic additives.

In addition, silicate mass can be used to achieve decorative effects or make jewelry. Using colorful silicate mixtures, you can give the silicate mass a marble effect.

Next, there are 22 examples of the manufacture and use of silicate masses of various compositions that correspond to the proposed invention.

The silica salts described below are manufactured by Bayer AG in Leverkusen. When describing polysiloxanes, commonly used symbols are used for silicon structural units, such as, for example, those used in the book "Chemistry and Technology of Silicon" by Walter Neuil, "Khimiya" publishing house, 1968, p.3. The letter "M" denotes monofunctional, "O" bifunctional, and "t" trifunctional structural units of organopolysiloxane, and "Me" denotes methyl groups. The polysiloxane preparations described below are products of GE Bayer Silicones GmbH and

Co. KG in Leverkusen.

Example 1

In 360 g of aqueous silicon sol with a 51O2 content of 50 wt.bo, a molar ratio of 190 mol of 51O" per mol of MagO5, an average particle size with a specific external surface area (VET) of 150 m2/g and a bimodal particle size distribution, at which bOv.95 sol particles had a specific external surface area of surface (VET) 50m2/g and 4Ovag.95 specific external surface (VET) 300m2/g, 20g of red pigment based on iron oxide with a particle size smaller than them was added as a dye. Then, as an aggregate, 160 g of mica with an average particle size of 35 inm was added and dispersed on the refiner for 10 minutes at a cutting speed of 12 to 15 m/s.

Finally, as a hydrophobic additive, 40g of an aqueous dispersion containing 50wg.9o of hydroxyfunctional alkylpolysiloxane with a low to medium degree of branching was added and mixed at a low shear rate of about 3m/s. As a hydroxy-functional alkylpolysiloxane, the emulsion "Beysilon Impregnate 3657" with the structure T(Me)coO (Me) o was used.

It turned out that the dispersion of dye and filler can occur faster at a higher viscosity. Therefore, in Example 2, only 2/3 of the total amount of silicon sol was initially introduced, and after dispersing the pigment and aggregate, the remaining third of the total amount of silicon sol was added.

Example 2

In 240 g of the aqueous silicon sol described in example 1, 20 g of a red pigment based on iron oxide with a particle thickness of less than 1 mm was added as a dye. Next, as an aggregate, 160 g of mica with an average particle thickness of 35 nm was added and dispersed on the refiner for 5 minutes at a transverse speed of 12 to 15 m/s. After that, a further 120 g of silicon sol and, as a hydrophobic additive, 40 g of the aqueous dispersion of alkylpolysiloxane described in Example 1 were added and mixed at a low transverse speed of about 3 m/s.

In both cases, a sedimentation-stable viscous silicate mixture was obtained each time, which could be stored for three months in a sealed container without impairing its properties.

Since mica has a thixotropic and therefore hardening effect, a viscosity suitable for further work was obtained with a relatively small amount of aggregate.

In the first experiment on the production of the coating, the silicate mixture was applied in a thin, even layer with the help of a spray gun on the hardened concrete roof stone. After two hours at room temperature, the layer was dry to the touch, and after about 24 hours at room temperature, it was completely hardened.

In the second experiment on the production of the coating, the silicate mixture was applied in a thin, even layer with the help of a spray gun on unhardened concrete roofing stone. The complete hardening of the layer took place together with the hardening of the concrete roof stone for several hours at 60"C in a humid atmosphere.

In both experiments, uniform defect-free coatings of red color with a silky gloss with an average thickness of 100 nm were obtained. Water collects in drops on the outer surface and practically does not seep into the coating. The coating is weather resistant.

In all subsequent examples of obtaining coatings, the silicate mixture was applied to hardened concrete roofing stone.

Example C

This example corresponds to example 2, however, as a hydrophobic additive, 40 g of "Baysilon impregnation 3641" emulsion, an aqueous dispersion with a content of 5Owag.9o of hydroxyfunctional alkylpolysiloxane with the structure T(Me)g7O(Me)om(Me)z, was used. The coating obtained from this silicate mixture was weather-stable, however, during transitions from freezing to thawing, it was somewhat less stable than in example 2. Moisture absorption was insignificant, but higher than in example 2.

Example 4

This example corresponds to example 2, however, as a hydrophobic additive, the base emulsion "Baysilon Impregnir 10", an aqueous dispersion with a content of 3.9% of methoxy-functional alkylpolysiloxane with the structure T(Me)pO(Me/Oodesu!)p, where p is equal to 1 to 10, was used as a hydrophobic additive. .The coating obtained from this silicate mixture was weather-stable, but slightly less stable during freeze-thaw transitions than in example 2. Moisture absorption was slight, but higher than in example 2. Water collects in drops.

Example 5

This example corresponds to example 2, however, as a hydrophobic additive, 35 g of an aqueous dispersion containing bOvag.9o dimethylpolysiloxane with a viscosity of 500 mRas was used. The coating made from this silicate mixture was comparatively the same as in Example 2, but it showed a higher chalking tendency.

Example 6 compared to US Patent 3,895,956 A.

This example corresponds to example 2, however, as a hydrophobic additive, instead of hydroxy-functional alkyl polysiloxane, 30 g of "Baysilon Impregnir ZK" emulsion, a 2595% aqueous solution of potassium methyl silicone was used. The coating made from this silicate mixture was weather-stable, but slightly less stable during freeze-thaw transitions than in example 2. Water absorption was negligible, although significantly higher than in example 2.

As the basis of the products obtained in execution examples from 2 to 6, for the following examples, the hydroxyfunctional alkylpolysiloxane used in examples 1 and 2 with the structure T(Me)vod (Me) o was used.

Examples from 7 to 11

In the following examples from 7 to 11, the content of the hydrophobic alkylpolysiloxane dispersion was varied.

For silicate mixtures, the same aqueous silicon sols and the same aqueous alkylpolysiloxane dispersions were used as in example 1. In 2/3 of the total amount of aqueous silicon sol, 20 g of a red pigment based on iron oxide with a particle size of less than 1 nm was introduced as a dye. Then, as an aggregate, 400 g of quartz powder with an average particle size of ZOrm and, as a hardener, 1.4 g of Benton EM from the Reox company were added and dispersed for 5 minutes with the help of a refiner at a high cutting speed of 12 to 15 m/s

GmbH in Leverkusen. Benton EM/ is a high-purity layered magnesium silicate. After that, the remaining third of the aqueous silicon sol and, as a hydrophobic additive, the alkyl polysiloxane dispersion were added and mixed at a lower speed of about 3 m/s.

Example 7

The silicate mixture contained ZbOg of silicon sol and 40g of alkylpolysiloxane dispersion. The product is the same as in example 2. The cured coating absorbed very little water and collected water droplets on it. Compared to other aggregates, the outer surface is more scratch resistant, although more matte than in example 2.

Example 8

The silicate mixture contained 320 g of silicon sol and 80 g of alkylpolysiloxane dispersion. A higher content of alkylpolysiloxane dispersion led to even less water uptake in the hardened coating, but the hardness of the coating was lower than in example 7.

Example 9

The silicate mixture contained 380 g of silicon sol and 20 g of alkylpolysiloxane dispersion. Compared to example 7, the hardened coating showed a higher water absorption and a noticeable collection of water droplets.

Example 10

The silicate mixture contained 390 g of silicon sol and 10 g of alkylpolysiloxane dispersion. Compared to Example 9, the cured coating showed even more water absorption and less noticeable collection of water droplets.

Example 11

This example was performed without the hydrophobic additive as a control experiment. The silicate mixture contained 400 g of silicon sol and no alkylpolysiloxane dispersion. The hardened coating absorbed water and water droplets did not collect. The coating did not pass the chalking test.

Example 12

For the silicate mixture, the same aqueous silicon sol and the same aqueous alkylpolysiloxane dispersion as in example 1 were used. In 36 g of aqueous silicon sol, 20 g of a red pigment based on iron oxide with a particle size of less than 1 nm was introduced as a dye. After that, 550 g of quartz powder with an average particle size of ZOnm was added as an aggregate and dispersed for 10 minutes with the help of an refiner at a high cutting speed of 12 to 15 m/s. Next, as a diluent, BG 50906 KOH was introduced, which brought the molar ratio to 70 mol of 5iOg2 per mol of alkali metal oxide. Finally, 40 g of an aqueous dispersion of alkyl polysiloxane was added and mixed at a lower cutting speed of about 3 m/s. The coating made from this mixture had mineral matting and high resistance.

Example 13

For the silicate mixture, the same aqueous silicon sol and the same aqueous alkylpolysiloxane dispersion as in example 1 were used. In 36 g of aqueous silicon sol, 20 g of a red pigment based on iron oxide with a particle size of less than 1 nm was introduced as a dye. After that, 550 g of quartz powder with an average particle size of ZOnm was added as an aggregate and dispersed for 10 minutes with the help of an refiner at a high cutting speed of 12 to 15 m/s. Next, 10 g of 5095 KOH was added as a diluent, which brought the molar ratio to 50 mol of 51iO2 per mol of alkali metal oxide. Finally, 40 g of an aqueous dispersion of alkyl polysiloxane was added and mixed at a lower cutting speed of about 3 m/s. The coating made from this mixture had mineral matting and high resistance.

Example 14

For the silicate mixture, the same aqueous silicon sol and the same aqueous alkylpolysiloxane dispersion were used as in example 1. 20 g of a red pigment based on iron oxide with a particle size of less than 1 nm was introduced as a dye into 300 ml of aqueous silicon sol. After that, 140 g of mica with an average particle size of Z5 was added as an aggregate and dispersed for 10 minutes with the help of an efinator at a high cutting speed of 12 to 15 m/s. Next, 21 g of 50906 KOH was introduced as a diluent, which brought the molar ratio to 26 mol of 5iO" per mol of alkali metal oxide. Finally, 40g of an aqueous dispersion of alkylpolysiloxane was added and mixed at a lower cutting speed of about 3m/s 40g of an aqueous dispersion of alkylpolysiloxane. The coating made from this mixture had a sharply shiny surface.

Example 15

The silicate mixture corresponded to example 7, but as a hardener, instead of EMU benton, 0.5 g of kelsan from Monsanto, Hamburg was used. Kelsan is an organic hardener. The molar ratio was 190 mol 5102 per mol MagO. In comparison with the inorganic hardener used in example 7, the same viscosity of the silicate mixture was achieved with a smaller amount of added hardener.

Example 16

For the silicate mixture, the same aqueous silicon sol and the same aqueous alkylpolysiloxane dispersion as in example 1 were used. In 380 g of aqueous silicon sol, 20 g of a red pigment based on iron oxide with a particle size of less than 1 nm was added as a dye. After that, 36b0g of quartz powder with an average particle size of ZOrm and 40g of needle-shaped wollastonite fibers with a diameter of less than 200nm were added and dispersed for 10 minutes with the help of an refiner at a high cutting speed of 12 to 15m/s. The length of wollastonite fibers was more than 20 diameters. Finally, as a hydrophobic additive, 20 g of an aqueous dispersion of alkylpolysiloxane was added and mixed at a lower shear rate of about 3 m/s.

The coating made from this mixture showed exceptionally high frost resistance due to fiber reinforcement.

Example 17

In 380g of an aqueous silicon sol with a content of 5iO2 ZOw.9o, a molar ratio of 148 mol 51O2 per mol

20 g of red pigment based on iron oxide with a particle size of less than 1 nm was added as a dye to Mago and an average particle size with a specific external surface area (VET) of 300 m"/g. After that, it was added as an aggregate and dispersed for 10 minutes using an efinator at at a high cutting speed of 12 to 15m/s 500g of quartz powder with an average particle size of ZO0im and, as a thickener, 1g of Benton EMU. Finally, as a hydrophobic additive, 20g of the aqueous dispersion of alkylpolysiloxane described in example 1 was added and mixed at a lower cutting speed of about 3m/ p. The use of silicon sol in a very small proportion with a solids content of no more than 3095 and in combination with a high content of aggregate leads to a coating with a mineral matte.

Example 18

In 240 g of aqueous silicon sol with a 5iO2 content of 50wg.9o, a molar ratio of 344 mols of 5iO" per mol MagO, an average particle size with a specific external surface area (VET) of 140m?/g and a trimodal distribution of particles, for which bOwg.oo sol particles had a specific external surface (VET) 50m2/g, 3w.9o specific external surface (VET) 200mg/g and 10wag.95 specific external surface (VET) 500m2/g, 20g of red pigment based on iron oxide with particle size was added as a dye less than 1rnm At the end, as an aggregate, 400 g of quartz powder with an average particle size of ZOnm and 1.4 g of bentonite were added as a thickener

EMUs were dispersed for 5 minutes with the help of an efinator at a high cutting speed of 12 to 15 m/s.

After that, at a lower shear rate of about Zm/s, further 140 g of aqueous silicon sol and, as a hydrophobic additive, the alkylpolysiloxane dispersion described in example 1 were added and mixed.

The use of a trimodal silicon sol with 50wg.9o of solids and a relatively low molar ratio of 5oOo to MoO resulted after solidification in obtaining a black glossy and, as shown by chalking tests, resistant to wiping coating.

Example 19

In 240g of aqueous silicon sol with a 51O2 content of 55.5wg.9o, a molar ratio of 172 mol of 5iO2 per mol of MagO and an average particle size with a specific external surface (VET) of 140m2/g and a bimodal distribution of particles, for which 70wg.9o sol particles had specific external surface (VET) of 50m2/g, and ZOw.9o specific external surface (VET) of 200mg2/g, 20g of red pigment based on iron oxide with a particle size of less than 1nm was added as a dye. At the end, 320g of quartz powder was added as an aggregate with an average particle size of ZOnm and was dispersed for 5 minutes with the help of an efinator at a high cutting speed of 12 to 15 m/s. After that, at a lower shear rate of about Zm/s, further 120 g of aqueous silicon sol and, as a hydrophobic additive, the alkylpolysiloxane dispersion described in example 1 were added and mixed. The use of a bimodal silicon sol with 55.5 g.2 o of solid matter and a relatively low content of aggregate led to obtaining an exceptionally strong and shiny coating after hardening.

Example 20

For silicate mixtures, the same aqueous silicon sol and the same aqueous dispersion of alkylpolysiloxane were used as in example 1. 40 g of unexfoliated white Bayertitan A pigment from Bayer AG, Leverkusen, with a titanium dioxide content of 9995 and a particle size of less than 1 room Then, as an aggregate, 360 g of calcareous flour caliber 5 from the Omya company in Cologne with an average particle size of 20 nm, with an average particle size of 20 nm, and 40 g of mica with an average particle size Z5rnm, as well as 2g of calcane and 2g of benton

EM. After that, at a lower cutting speed of about 3m/s, 40g of an aqueous dispersion of alkylpolysiloxane was added and mixed. This silicate mixture was used as a facade paint and formed an intensely white, mineral-matte and wipe-resistant coating on cement plaster.

Example 21

For silicate mixtures, the same aqueous silicon sol and the same aqueous dispersion of alkylpolysiloxane were used as in example 1. 1060 g was added to 380 g of aqueous silicon sol as a filler, and for 5 minutes it was dispersed with the help of an refiner at a high cutting speed of 12 to 15 m/s quartz flour with an average particle size of ZOnm and 160 g of microsilica OR 983 of Elkem GmbH, which in

Dusseldorf, with a particle size of less than 45 nm. At the end, 20 g of an aqueous dispersion of alkyl lysiloxane was added and stirred at a lower cutting speed of 3 m/s. This silicate mass with a very high solids content was used as a viscous and well-flowing molding mass for the manufacture of massive molded products. Strong flat monolithic molded products were produced that accurately reproduced the contours of the molds, had no cracks, and had very little porosity.

Example 22

In 400 g of the bimodal silicon sol described in example 1, which, in order to improve the technological properties and resistance to delamination at low temperatures down to -57C, contained 595 g of ethylene glycol, was added and dispersed for 5 minutes with the help of an refiner at a high cutting speed of 12 to 15 m/s, as filler, 900g of fireclay flour with a particle size of less than 100rm and, as a thickener, 2.4g of Benton

EM. At the end, 20 g of the aqueous dispersion of alkylpolysiloxane described in example 1 was added and dispersed at a low speed of about 3 m/s. The silicate mass obtained in this way is a viscous paste, which, for example, can be worked with a spatula. This paste is only advisable to use for fixing internal fireclay pipes in domestic chimneys.

In both segments of a fireclay pipe cut in half with a diameter of 17 mm and a wall thickness of 15 mm, a thin layer of the previously described silicate mass was applied to each of the end surfaces, the ends of the pipe segments were attached to each other, and the silicate mass was cleaned from the protruding sides. After 24-hour drying at room temperature, when performing three-point bending tests with a distance between supports of 250 mm, the destructive load was more than 1500N. The strength of the combination noticeably deteriorates when in water, or when heated at temperatures up to 110070. The compound is acid-resistant.