WO2015155034A1 - Dry plaster mortar having hydrophobing additive - Google Patents

Abstract

The invention relates to a plaster dry mortar containing A) 100 parts by mass plaster; B) at least 20 parts by mass mineral filler; C) an organosilicon compound, which is solid at 20°C and is selected from organosilicate powder C1 and organosilicon compounds C2 which can be produced by reacting a molar equivalent of silane S, selected from hydrocarbon trihalogen silane, hydrocarbon trihydrocarbon oxysilane, or mixtures thereof, or partial hydrolysates thereof, with polyhydroxy compounds P in a molar ratio such that there are 0.3 to 1.3 molar equivalents hydroxy radicals per molar equivalent halogen or hydrocarbon oxy radical; D) a fatty acid compound, which is selected from fatty acid D1, fatty acid salt D2, and fatty acid ester D3.

Description

 Plaster dry mortar with water repellent additive

The invention relates to a gypsum dry mortar with a

Organosilicon compound and fatty acid compound as

Water repellent additive.

Organosiliconates have been used for decades

Hydrophobing, i. water-repellent equipment,

used in particular by mineral building materials. In general, these are inorganic building materials, which may be silicate and non-silicate nature. Due to their good solubility in water, organosiliconates can be applied as an aqueous solution to solids where, after evaporation of the water under the influence of carbon dioxide, they form firmly adhering, permanently water-repellent surfaces. Since they contain virtually no hydrolytically removable organic radicals, the curing takes place advantageously without release

undesirable volatile organic by-products (so-called VOC). Above all, the aqueous solution of methyl silicate is of great importance. This is in particular the

Potassium (potassium methylsiliconate) or the sodium derivative

 (Sodium methylsiliconate).

Aqueous solutions of Organosiliconaten ^' are particularly good for hydrophobing of weakly acidic to weakly alkaline

Suitable building materials, especially of products made of baked clay, natural stone or gypsum. The application of the

Hydrophobic agent either by impregnation or

Mass hydrophobing done. In the impregnation, for example, products of calcined clay or natural stone are immersed in an aqueous dilution of the organosiliconate for a certain time or sprayed with such a dilution, the active substance dissolved in water being capillary in the pore structure of the Building material penetrates. Depending on the prevailing conditions, after a period of a few minutes to several hours to a few days after drying of the building material, a hydrophobic zone develops that surrounds the building material and drastically reduces its capillary water absorption. In the

Mass hydrophobization becomes the aqueous solution of the

Organosiliconate optionally after further dilution with the

aqueous slurry (for example, "slurry"), for example, of a building material based on the binder gypsum After setting and drying of the building material, a greatly reduced water absorption of the gypsum building material is compared with the

measured unhydrophobic building material. The advantage of

Mass hydrophobization e.g. of gypsum is that the building material is not only surrounded by a hydrophobic zone, but water repellent through and through. This is particularly important in the case of water-soluble building materials such as gypsum or when the building material is cut into pieces after the water-repellent treatment. This method finds e.g. in the

Production of plasterboard, gypsum wallboard or gypsum fibreboard application.

Gypsum-based plasters, fillers, screed or self-leveling compounds and adhesives, all of which belong to the gypsum-dry mortar family, are delivered to the construction site as powder in sacks or silos and only then mixed with the mixing water. For use in gypsum plasters, gypsum filler, gypsum plaster, gypsum-based tile adhesives, gypsum-based soil leveling compounds and screed materials and similar mineral building materials is therefore a solid and

powdered hydrophobing agent required by the

ready-to-use dry mix can be added and only with the addition of water during the application on site, eg on the construction site, in a short time unfolds its hydrophobic effect. This is called dry-mix application.

Standard EN 520 specifies a water absorption, measured for two hours, of less than 5% for the water absorption class Hl of hydrophobic plasterboard approved for use in wet rooms. The skilled person is aware that bound

gypsum-based dry mortar, which is in the range of possible

Moisture penetration must also have a water absorption of less than 5%. the

One skilled in the art is also aware that for ligated

Dry mortar also the water absorption, measured during 24 hours, is of great importance.

 DE1957263 describes a method for building gypsum walls in underground operation. A pumpable and thus per se liquid gypsum slurry containing, among other additives

Potassium siliconate and a stearate will be backfilled and

Caulking cavities used in pits. However, the potassium siliconate does not necessarily come in solid form

Use and the stearate takes over the task of a

Condenser. It is not clear from the description that all additives are necessarily added in powder form to the gypsum powder filled in a sack. In addition, neither

Evidence of the hydrophobing property supplied nor the combination of both products in powder form described as advantageous for the hydrophobization of a stored in powder gypsum.

 Also in DD291074 is a Kaliumpropylsiliconat with a

Sodium linoleate combined in a Sanierputz, but here the siliconate is added in liquid form. Furthermore, the redevelopment plaster described is based on the binder cement, and not on gypsum.

WO2012 / 022544 describes the preparation of pulverulent alkali metal alkyl siliconates having different molar ratios Potassium to silicon and their advantages in the additive of gypsum-bound dry mortars, such as lime gypsum plaster. In the corresponding application example 3 with a lime-gypsum machine plaster, 0.3% by weight of a potassium methylsilonate powder with a molar ratio of potassium to silicon of 0.64 leaves the water absorption after 2 hours (based on EN 520) in comparison to the untreated reference decrease by over 90%. The lime-plaster machine plaster used here is a so-called low-filled plaster with a proportion of settable gypsum phases of about 60%. Such gypsum plaster contains a low content of fillers (or also called aggregates) due to its relatively high proportion of settable gypsum phases. Such

Fillers may include, for example, artificial or natural aggregates as well as minerals of different

 Grain size distributions, e.g. Alkaline earth carbonates (e.g., calcite, dolomite), alkaline earth sulfates (e.g., calcium sulfate in the form of gypsum or anhydrite), chippings, natural sands, or

Quartz sand (a more specific description can be found elsewhere in the text). Even if the water absorption after 24 hours underwater storage measures, occurs at a dosage of 0.3 wt .-% of the same potassium methylsilionate a reduction in water absorption compared to the untreated reference of about 80%.

A problem arises when using the potassium methylsilionate powder on special high-filled lime-gypsum machine plaster, in which the proportion of settable gypsum phases is only about 20% and the content of fillers is correspondingly higher and is around 80%. Although 0.3% by weight of a potassium methylsilonate powder with a molar ratio of potassium to silicon of 0.64 can also be used here

Water absorption after 2 hours (based on EN 520) in

Compared to the untreated reference by more than 90% decrease, the Water absorption at 24-hour measurement, however, only drops to values of about 50% compared to the untreated reference. An increase in the dosage of potassium methylsilonate powder does not solve the problem, since this class of substance at excessive dosage (which goes well beyond the hydrophobic minimum, which in turn is to be determined individually for each gypsum-based dry mortar formulation) undesirable side effects on those with water

has mixed gypsum mortar. These side effects include the formation of sintered layers as well as loss

Air pore content and flowability, resulting in a

Deterioration up to the complete loss of

Processability of gypsum mortar results. A measure of the processing properties of the mixed with water

Fresh mortar is the slump, which can be determined according to EN 1015-3 with a hammermannel. The air pore content is measured using an appropriate measuring device according to EN 1015-7

certainly. When using potassium methylsilonate powders in different dosages in a fresh with water

mixed lime plaster machine plaster falls on that

 Slump drastically decreases from a dosage of "0.3% by weight" For this reason, an overdose should only be used to reduce water absorption after 24 hours of underwater storage

be avoided.

The invention relates to a gypsum dry mortar

containing

 A) 100 parts by mass of gypsum,

B) at least 20 parts by mass of mineral filler,

C) at 20 ° C solid organosilicon compound which is selected from Organosiliconatpulver Cl and organosilicon compounds C2, which can be prepared by reacting a molar equivalent of Silane S, which is selected from

 Kohlenwasserstofftrihalogensilan,

 Kohlenwasserstofftrikohlenwasserstoffoxysilan or mixtures thereof or their Teilhydrolysate with polyhydroxy compounds P in such a molar ratio that per molar equivalent of halogen or Kohlenwasserstoffoxyrest 0.3 to 1.3 molar equivalents

Hydroxy radicals are present,

 D) fatty acid compound selected from fatty acid Dl, fatty acid salt D2 and fatty acid ester D3.

The problem described for highly filled lime gypsum plasters is solved when the gypsum dry mortar in addition to

Organosilicon compound C nor fatty acid compounds D

be added. By combining these two

hydrophobizing additives can be reduced by over 80% and the 2-hour water absorption in the 2-hour by more than 80% compared to the untreated reference. First, it is unexpected that the proportion of each additive C or D used in the total dosage of the combination of both additives C and D used alone is not effective in the desired form. Secondly, it is unexpected that the two individual additives, used alone in the same dosage as the total dosage of the combination of both additives C and D, are also not effective in the desired form. The latter case is a synergy, since the combination of the two additives C and D is more effective than either of the two individual additives, to the same

Amount used.

Likewise, in the case of the combination of the two additives C and D, in particular when using potassium methylsiliconate powder as additive C and fatty acid salt as additive D, the slump in accordance with EN 1015-3 is not so strongly influenced as if, for example Potassium Methylsiliconatpulver is used in accordance with higher dosage. The gypsum dry mortar is powdery.

As gypsum A all plasters come into question. Among the gypsum so-called reactive plasters are preferred: calcium sulfate hemihydrate or hemihydrate (CaSC> 4 * 0.5 H ₂ 0), in the alpha and in the beta form and in the form of, for example, building plaster, stucco, plaster or gypsum (English stucco or plaster of Paris), and anhydrites (CaSO-4, anhydrite I, II and III), as obtained from known Calcinierverfahren, starting from occurring

Gypsum or artificially made gypsum. In the calcination, the phases calcium sulfate dihydrate, calcium sulfate hemihydrate and anhydrite I, II and III in their different forms in different

Proportions and mixtures are incurred (multiphase plasters). Other types of plaster, such as screed plaster, marble plaster, anhydrite,

Recycled gypsum and man-made plasters (at the

Flue gas desulphurisation, the production of phosphorus and

Hydrofluoric acid or derived from organic carboxylic acids) are suitable.

As a mineral filler B are particularly suitable

natural and synthetic fillers such as lime, limestone, limestone sand, limestone flour, limestone giants, carbonates,

Silicas, silicas, silicates, sulfates, nitrides, carbides, ashes, expanded mineral lightweight fillers and clays. Extremely suitable alkaline earth carbonates such. Calcium carbonates, calcium magnesium carbonates, chalk, calcite and dolomite, alkaline earth sulfates, e.g. barium sulfate,

Strontium sulfate, barite, Blanc Fixe and calcium sulfate are preferred in the form of its phases or modifications of gypsum, bassanite or anhydrite, silicas such.

Quartz and quartz flours, silicates such as diatomaceous earth, celite, Clays, zeolites, calcium silicate, zirconium silicate, cristobalite, talc, bentonite, kaolin, china clay, mica, muscovite,

 Silicas such as e.g. Precipitated silica, pyrogenic

Silicas or diatomaceous earth, metal oxides such as e.g. Aluminum, titanium, iron or zinc oxides and their mixed oxides,

Silicon nitride, silicon carbide, fly ashes, microsilica,

Microfiller, perlite, vermiculite, expanded glass, and expanded clay. The mineral filler B can be different

Have grain size distributions, it can also be used as a split or sand. The mineral filler B may also be in the form of mineral fibers, such as glass fibers, glass and

Rock wool, or wollastonite present. The grain size of the mineral filler B is preferably between 1 and 3000 micrometers, more preferably between 5 and 2500

Micrometer and most preferably between 10 and 2000 microns.

 The gypsum dry mortar contains 100 gypsum plaster

preferably at least 25 parts by mass and at most 900

Parts by mass of mineral filler, more preferably preferably at least 30 parts by mass and at most 700

Parts by mass of mineral filler, most preferably at least 35 parts by mass and not more than 500

Parts by mass of mineral filler, in particular at least 40 parts by mass and at most 300 parts by mass of mineral

Filler.

The Organosiliconatpulver Cl used according to the invention can carry as a cation alkali or alkaline earth metals or their mixtures with each other. Particularly preferred are the sodium and potassium organosiliconates. The organosiliconate powder Cl used can be the solid salts of organosilanols described in O2012 / 159874. There is also described a process for the preparation of Organosiliconatpulver Cl. The organosiliconate powders Cl are preferably solid salts of organosilanols, of their hydrolysis / condensation products, or of organosilanols together with theirs

Alkali cation hydrolysis / condensation products in which the molar ratio of cation to silicon is 0.5 to 3.

 The organo-group is preferably a monovalent one

unsubstituted or substituted by halogen atoms, amino, alkoxy or silyl hydrocarbon radical

preferably 1 to 18 carbon atoms. Particular preference is given to unsubstituted alkyl radicals, cycloalkyl radicals,

Alkylaryl radicals, arylalkyl radicals and phenyl radicals. The hydrocarbon radicals preferably have 1 to 6 carbon atoms, more preferably the 3, 3, 3-trifluoropropyl, the vinyl and the phenyl radical, very particularly preferably alkyl radicals, such as the ethyl, propyl, butyl, pentyl, Hexyl, heptyl, the octyl and the hexadecyl and their possible

Consumption isomers, the most preferred is the

Methyl radical.

Further examples of the organo radical are:

n-propyl, 2-propyl, 3-chloropropyl, 2- (trimethylsilyl) ethyl, 2- (trimethoxysilyl) ethyl, 2- (triethoxysilyl) ethyl, 2- (dimethoxymethylsilyl) ethyl, 2- (diethoxymethylsilyl) ethyl, n-butyl, 2-butyl, 2-methylpropyl, t-butyl, n-pentyl,

Cyclopentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, 10-undecenyl, n-dodecyl , Isotridecyl, n-tetradecyl, n-hexadecyl, vinyl, allyl, benzyl, p-chlorophenyl, o- (phenyl) phenyl, m- (phenyl) henyl, p- (phenyl) phenyl , 1-naphthyl, 2-naphthyl, 2-phenylethyl, 1-phenylethyl, 3-phenylpropyl, 3- (2-aminoethyl) aminopropyl, 3-aminopropyl, N-morpholinomethyl, N-pyrrolidinomethyl, 3- (N-cyclohexyl) aminopropyl, 1-N-imidazolidinopropyl.

Further examples of the organo radical are radicals - (CH 2 O) n R ¹ ,

- (CH ₂ CH ₂ 0) _m -R ² , and - (CH ₂ CH ₂ NH) ₀ H, where n, m and o are from 1 to 10, in particular 1, 2, 3 and RL, alkyl radicals having 1 to 6 carbon atoms, especially those above

mentioned examples mean.

In gypsum dry mortar can also mixtures of

different substituted Organosiliconatpulvern, so modified with different organo radicals used. Alkali monorail organosilicon powder,

Alkalidiorganosi1iconatpulver and

 Alkalitriorganosiliconatpulver each alone or in

Combination can be used together.

 The described positive effect from the invention

Combination of additives C and D can with

 Organosiliconate powders Cl of different molar ratios

 Alkali metal to silicon can be achieved. Preferred is a ratio between 0.1 and 3.0, more preferred is a

Ratio between 0.3 and 2.0, exceptionally preferred is a ratio between 0.5 and 1.5.

The organosilicon compounds C2 used according to the invention may be those described in WO2013 / 053609

 Organosilicon compounds be 0. There is also described a process for the preparation of the organosilicon compounds C2. Preferably, the hydrocarbon radicals of the silane S are optionally substituted Ci-C] _5 hydrocarbon radicals. Examples of the Ci-C ^ hydrocarbon radicals are

Alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert. Butyl, n-pentyl, iso-pentyl, neo Pentyl, tert. -Pentyl radical; Hexyl radicals, such as the n-hexyl radical; Heptyl radicals, such as the n-heptyl radical; Octyl radicals, such as the n-octyl radical and iso-octyl radicals, such as the 2, 2, 4-trimethylpentyl radical; Nonyl radicals, such as the n-nonyl radical; Decyl radicals, such as the n-decyl radical; Dodecyl radicals, such as the n-dodecyl radical; Alkenyl radicals, such as the vinyl and allyl radicals; Cycloalkyl radicals, such as

Cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl radicals; Aryl radicals, such as the phenyl, naphthyl,

Anthryl and phenanthryl radical; Alkaryl radicals, such as o-, m-, p-tolyl radicals; Xylyl radicals and ethylphenyl radicals; Aralkyl radicals, such as the benzyl radical, the alpha- and the 3-phenylethyl radical,

Examples of substituted C _] _-C] _5 hydrocarbon radicals are substituted by fluorine, chlorine, bromine and iodine atoms

Alkyl radicals, such as the 3, 3, 3-trifluoro-n-propyl radical, the

2, 2, 2, 2 ', 2', 2, ^1- hexafluoroisopropyl radical, the heptafluoroisopropyl radical, and haloaryl radicals, such as the o-, m- and p-chlorophenyl radical, if silane S is a

Hydrocarboxylic oxy-silane acts with amino functions

substituted alkyl radicals such as the 3-aminopropyl radical, the N-phenyl-aminomethyl radical, the 2-3- (2-aminoethyl) aminopropyl radical, the N-morpholinomethyl radical, the N-octylaminomethyl radical, thiol-substituted alkyl radicals such as

Thiopropyl, epoxy-substituted alkyl radicals such as Glycidoxypropylrest, Ethylcyclohexenoxidrest.

Particularly preferred are the unsubstituted -C ^ _Q alkyl radicals, especially the methyl radical and ethyl radical.

The hydrocarbonoxy radicals of the silane S are preferably C 1 -C 4 -hydrocarbonoxy radicals. Examples of the Ci-C ^^ -

Kohlenwasserstoffoxyreste are the above C ^ -C ^ -

Hydrocarbon radicals which have a bivalent

Oxygen atom are bonded to the silicon atom. Especially preferred are the non-substituted C 1 -C 3 -alkyl radicals, in particular the methyl radical and the ethyl radical.

Preferably, the halo radicals of the silane S are chlorine radicals.

The silane S may contain even small amounts, preferably at most 5 mol%, in particular at most 2 mol%, of silanes which are selected from dihydrocarbyl dihalosilane,

Trihydrocarbylhalosilane, tetrahalosilane,

Dihydrocarbyl dikohlenwasserstoffoxy-silane,

Trichlorohydrocarboxylic oxy-silane and

Tetrahydrocarbonoxy silane.

The silane S may also contain small amounts, preferably at most 5 mol%, in particular at most 2 mol% of siloxanes, which are formed by hydrolysis from the silane S.

The silane S may also contain minor proportions, preferably at most 5 mol%, in particular at most 2 mol%, of disilanes, e.g. from distillation residues of

Methylchlorosilane production.

In addition to halogen and hydrocarbonoxy radicals, the silane S may contain small amounts, preferably not more than 10 mol%, in particular not more than 5 mol% of Si-bonded hydrogen.

The polyhydroxy compound P is preferably a linear or branched monomeric or oligomeric C2-C5-

Glycol, and mixed glycols, in particular C2-C glycol having a total of at most 40 carbon atoms, preferably

at most 25, in particular at most 15 carbon atoms, tri-, tetra-, penta- and hexahydroxy compounds having 3 to 12 carbon atoms and C2-C12-hydroxycarboxylic acids. Particularly preferred among the glycols are ethylene glycol or its oligomers, propylene glycol or its oligomers, and mixed glycols with propylene glycol and ethylene glycol units. Preferably, the oligomers have at most 6, in particular at most 3 monomer units. Examples of branched or linear C2-C25 glycol radicals are alpha-omega hydroxy-functional glycols such as ethylene glycol, propylene glycol (= 1, 2-propanediol), 1, 3-propanediol, 1-butanediol, 1,5-pentanediol, 1, 6-hexanediol , Neopentyl glycol, pinacol, di-, tri- and tetraethylene glycol, di-, tri- and tetra-propylene glycol, alpha-omega hydroxy-functional mixed glycols from 1-5

Ethylene glycol units and 1-5 propylene glycol units and mixtures thereof and bis (hydroxymethyl) urea.

Particularly preferred are propylene glycol and ethylene glycol, in particular propylene glycol.

Among the tri-, tetra-, penta- and hexahydroxy compounds having 3 to 12 carbon atoms, particularly preferred are linear or branched tri-, tetra-, penta- and

 Hexahydroxy compounds having 3 to 12 carbon atoms.

Examples are glycerol, 1, 2, 4-butanetriol, 1,1,1-tris (hydroxymethyl) ethane, pentaerythritol, meso-erythritol, D-mannitol, saccharides such as D- (+) -mannose, D- (+) - Glucose, D-fructose. Furthermore, their condensation products, di- and polysaccharides such as D- (+) - sucrose, cyclodextrins, cellulose and starch and their derivatives, e.g. their methyl, ethyl and hydroxyethyl derivatives or partially or fully saponified polyvinyl acetates are used.

Among the C2-C12-hydroxycarboxylic acids, preferably C2 ~ Cg-

Hydroxycarboxylic acids particularly preferred are aromatic and linear or branched hydroxyalkylcarboxylic acids, such as Salicylic acid, mandelic acid, 4-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 3, 5-dihydroxybenzoic acid, glycolic acid, lactic acid, 2,2-bis (hydroxymethyl) propionic acid, tartaric acid, citric acid, 3-hydroxybutyric acid, 2-hydroxyisobutyric acid, particularly preferred are linear or branched

Hydroxyalkylcarbonsäuren, in particular lactic acid.

Preferably, at least 0.5 molar equivalents, particularly preferably at least 0.7, in particular at least 0.9 and preferably at most 1.3, more preferably at most 1.2, in particular at most 1.1 hydroxyl groups, derived from the polyhydroxy compound P, per molar equivalent of halogen or

Hydrocarbonoxy used in silane S. Preference is given to using silanes S having a hydrocarbonoxy radical, particularly preferably alkyltrialkoxysilanes. Examples are methyltrimethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, isopropyltrimethoxysilane, n-butyltrimethoxysilane, 2-methyl-1-propyltrimethoxysilane, 2-butyltrimethoxysilane, cyclohexyltrimethoxysilane, 2-cyclohexyl-1-ethyltrimethoxysilane, n-hexyltrimethoxysilane,

Isohexyltrimethoxysilane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, isooctyltrimethoxysilane,

Decylimethoxysilane, undecyltrimethoxysilane,

Dodecyltrimethoxysilane, hexadecyltrimethoxysilane.

Particularly preferred polyhydroxy compounds P are lactic acid, propylene glycol and glycerol. The gypsum dry mortar contains 100 gypsum plaster

preferably at least 0.02 parts by mass and at most 4

Parts by mass of organosilicon compound C, more preferably at least 0.05 part by mass and at most 3 parts by mass Organosilicon compound C, in particular at least 0.1

Mass parts and at most 2 parts by mass

Organosilicon compound C.

As the fatty acid D1, lower (up to seven carbon atoms), middle (eight to twelve carbon atoms) and higher (more than twelve carbon atoms) fatty acids may be used, with lower fatty acids being more preferred, medium fatty acids being more preferred, and higher fatty acids being highly preferred. In the case of the fatty acid salt D2, main and subgroup metals may be used as cations for the fatty acid anion described above. Preference is given to alkali metals,

Alkaline earth metals and metals of group 12 of the Periodic Table of the Elements. The metals lithium and strontium are particularly preferred. Most preferably, the metals are sodium, potassium, magnesium, calcium, barium, zinc and aluminum.

Examples of particularly preferred and exceptionally preferred fatty acid salts are calcium stearate, calcium 12-hydroxystearate, calcium laurate, calcium behenate, barium stearate, barium laurate, zinc stearate, zinc behenate, zinc laurate, zinc oleate,

Magnesium stearate, aluminum di- or aluminum tristearate, sodium oleate, sodium stearate, potassium oleate, lithium stearate, lithium 12-hydroxystearate. As cations to the fatty acid anion, ammonium and alkylammonium, e.g.

Trimethylammonium, triethylammonium, triisononylammonium, tris-2-ethylhexylammonium, pyridinium, guanidinium,

 Tetramethylguanidinium, imidazolium, N-methylimidazolium, or alkanolammonium, e.g. Bis (2-hydroxyethyl) ammonium or

Diethanolammonium, triethanolammonium be used.

The fatty acid esters D3 are preferably solid to pasty at room temperature. Examples are alkyl esters of fatty acids of the general formula RCOOR ', where R is a linear or branched, saturated or unsaturated, unsubstituted or substituted hydrocarbon radical having 4 to 22, preferably 6 to 16, carbon atoms, and R * is a linear or branched, saturated or unsaturated unsubstituted or substituted hydrocarbon radical having 1 to 50, preferably 2 to 30, especially preferably 3 to 16 carbon atoms represented by one or more

Oxygen atoms may be interrupted, wherein in each case at least one carbon atom is located between two adjacent oxygen atoms. Also mono-, di and

Triglycerides of saturated fatty acids such as hydrogenated fats (e.g., hardened soybean oil, hydrogenated sunflower oil, hardened peanut oil, hydrogenated rapeseed oil). The gypsum dry mortar contains 100 gypsum plaster

preferably at least 0.01 mass parts and at most 3

Parts by mass of fatty acid compound D, particularly preferred

at least 0.05 parts by mass and at most 2 parts by mass

Fatty acid compound D, in particular at least 0.1 parts by mass and at most 1 part by mass of fatty acid compound D.

The combinations of the invention

 Organosilicon compound C and fatty acid compound D are in the sum of both additives, preferably in dosages between 0.02 and 6.0 parts by mass intimately with a

 Gypsum dry mortar formulation containing gypsum A and mineral filler B, especially in the dry state

Condition mixed. Preferably, dosages between 0.1 and 4.0 parts by mass, exceptionally preferred dosages between 0.2 and 2 parts by mass. The weight ratio of the two

Components organosilicon compound C and fatty acid compound D is freely selectable in the gypsum dry mortar and to determine by appropriate experiments, preferably is a Weight ratio between 0.25 and 4, more preferably a weight ratio between 0.33 and 3, and most preferably a weight ratio between 0.5 and 2.

It is also possible to generate the fatty acid salt D2 in situ by replacing the fatty acid salt D2 with a

added powdered fatty acid Dl. The fatty acid salt D2 is then selected from the fatty acid D1 and that in the organosiliconate powder Cl (based, for example, on NaOH or KOH) or in the

Building material formulation (formed by the proportion of, for example, CaO or Ca (OH) 2) contained alkalinity. Among the solid fatty acids D1 are lauric acid, palmitic acid and stearic acid

prefers .

 Not exclusively for setting a desired pH of the gypsum dry mortar, these amounts of cements, preferably Portland white and Portlandgrauzement, and alkali and alkaline earth oxides and hydroxides, preferably calcium oxides, calcium, magnesium, magnesium,

contain .

 The plaster dry mortar may contain pigments such as synthetic or natural pigments to produce a desired hue. Preferably, they are oxide and

Oxide hydrate pigments, sulfide and sulfoselenide pigments,

Chromate pigments and chromate pigments,

Ultramarine pigments, iron blue pigments and pigment blacks.

Particularly preferably, the white pigments are titanium dioxide in the anatase and rutile form, zinc sulfide and zinc (oxide) white, the

Black pigments iron oxide black, spinel black and

Carbon black, and the colored pigments iron oxide red, cadmium orange, cadmium red, molybdate orange, molybdate red, iron oxide yellow,

Zinc ferrite yellow, nickel ruthenium yellow, chrome ruthenium yellow, bismuth vanadate, cadmium yellow, chrome yellow, iron oxide brown, mangantite brown,

Chrome-Brown, Chrome Oxide Green, Chromium Oxide Hydrate Green,

Cobalt green, cobalt blue, ultramarine blue and iron blue. The Grain sizes of the pigments are preferably between 0.01 and 100 micrometers, more preferably between 0.1 and 10

Micrometer.

The gypsum dry mortar may contain further components, such as polymer powders, polymeric organic binders,

Celluloses and cellulose ethers, starches and starch ethers,

Flow aids, thickeners, adhesion promoters, air entraining agents, retarders, accelerators, inorganic or organic

Pigments, biocides, defoamers, deaerators and anti-caking agents. Optionally, gypsum dry mortar may also include organic fillers, organic pigments, soluble inorganic and organic dyes, organic fibers (e.g., cellulosic, polyalkylene, polyvinyl alcohol, polyvinyl acetate fibers),

Waxes, phase change materials (PTM), Oleophobierungsmittel, or other water repellents in solid or after

Be added water in liquid form.

The gypsum dry mortar, for example, a plaster, a

Putty, a joint filler, a screed, one

Self-leveling compound, a model or hobby plaster, a

Impression material, an adhesive or a combination.

All the above symbols of the above formulas each have their meanings independently of each other. In all

Formulas is the silicon atom tetravalent. All data refer to a pressure of 0,10 MPa (abs.)

In the following examples and comparative examples, unless stated otherwise, all amounts and

Percentages by weight and all

Reactions are carried out at a pressure of 0.10 MPa (abs.)

carried out . In the following application examples were customary

MGP 1 used in powder form: MGP 1 is a low-filled lime-gypsum machine plaster with a proportion of settable gypsum phases of about 60% and a consequent proportion of about 40% fillers), MGP 2 is a highly filled lime -Gypsum -machine plaster with a share in

settable gypsum phases of about 20% and a consequent proportion of about 80% fillers). The plasters were treated with varying amounts of potassium methylsiliconate powder and

Fatty acid salts in dry form are effectively mixed in a so-called planetary mixer as described in EN 196-1 for 30 seconds. Subsequently, this dry mixture was added in portions to the mixing water in accordance with the recipe indicated on the packing with stirring and mixed with the planetary mixer as described in EN 196-1 to form a homogeneous slurry (MGP 1: 300 g of powder and 180 g of water, MGP 2: 300 g powder and 105 g water according to the instructions). Subsequently, the resulting slurry was poured into PVC rings (diameter: 80 mm, height 20 mm) and the setting of gypsum plaster at 23 ° C and 50% relative humidity was waited for 6 hours. After

Reshaping the gypsum plaster test specimens from the rings, these were stored for another 24 hours at 23 ° C and 50% relative humidity separately from each other standing on the lateral surface and then dried in a convection oven at 40 ° C to constant weight of the test specimens. In the case of Application Examples 22-27, the test specimens were stored before storage in water for 28 days under standard conditions (23 + 2 ° C, 50 ± 5% relative humidity according to EN 1062-3). to

Determining the absorption according to DIN EN 520, the test specimens were stored in a plastic trough under water after determining the dry weight for 120 min

Samples were placed horizontally on metal mesh and the Water supernatant above the highest point of the test specimen was 5 mm. After 120 minutes, the test specimens were removed from the water, drained on a water-saturated sponge, and on a balance with an accuracy of 0.01 g from the wet weight and the dry weight the percentage

Water after 120 minutes according to the formula

Percent water absorption = {[mass (wet) - mass (dry)] / mass (dry)} · 100% calculated. After weighing, which took only a few seconds per test specimen, the test specimens were immediately returned to the plastic tray under water. After a

Total time of 24 h under water, the test specimens were again taken out of the water and the percentage of water uptake after 24 h, as previously described for 120 min, determined.

Application Examples 1-27: Hydrophobization of Two

Maschinengipsputze with varying dosages on one

Potassium Methylsiliconatpulver (molar ratio of alkali metal to silicon: 0.65) and various fatty acid salts or

Pul erförmigen fatty acids.

 Table 1 shows, in the case of Application Examples 1 and 2, that the potassium methylsiliconate powder contains the 2-h water uptake and the 24-hr water uptake of a low-filled water

 Machine plaster gypsum (MGP 1) at a dosage of 0.22 wt .-% greatly reduced.

 In the case of Application Examples 3-6, Table 1 shows that neither 0.13 wt.% Nor 0.26 wt.% Of potassium methylsiliconate powder exalts both the 2-h and 2-hr. Water intakes of one filled machine plaster gypsum (MGP 2) to values

can lower simultaneously under 10 wt .-%. Also, sodium oleate can not absorb the 2 h and 24 h waters in 0.13 Wt .-% still 0.26 wt .-% reduce dosage to values below 20 wt .-% (Application Examples 7 and 8).

 Unexpectedly, however, it is possible with a combination of the two additives potassium methylsiliconate powder and sodium oleate, both the 2 h and the 24 h water uptake of the highly-filled engine plaster gypsum (MGP 2) to values below 5 wt .-% to lower (Application Example 9). It is also unexpected that this is possible with a combination of 0.15% by weight potassium methylsiliconate powder and 0.11% by weight of sodium oleate, while neither 0.15% by weight of potassium methylsiliconate powder is used individually (US Pat. Application Example 5) still 0.11 wt .-% sodium oleate used separately (Application Example 7) or 0.26 wt .-% potassium methylsiliconate powder used separately (Example of Application 6) or 0.26 wt .-% sodium oleate used separately (Example of application 8) lower both the 2-hr and 24-hr water pick-ups to less than 10 weight percent. This is a synergistic effect.

Application Examples 10-21 show that the effect is similarly observed with the fatty acid salts potassium oleate, calcium stearate, zinc laurate and calcium laurate. For example, lower values are always measured for 2 h and 24 h water when potassium methylsiliconate powder and fatty acid salt are combined than when the two components are used individually in the same amount.

Application examples 22-27 show that the same effect can be achieved / if, instead of the fatty acid salt, a powdery fatty acid solid at room temperature is used. Again, even low dosages of lauric acid or stearic acid in combination with a low dosage of potassium methylsiliconate powder used alone the highly-filled machine plaster MGP 2 not effective

to reduce both the 2-hr and 24-hr water pick-ups to less than 5 wt.%. Table 1: Water absorption of gypsum plaster test specimens in accordance with DIN EN 520

* not according to the invention

Table 1: Water absorption of gypsum plaster test specimens in accordance with DIN EN 520 (continued)

 * not according to the invention

Claims

claims  1. gypsum dry mortar containing  A) 100 parts by mass of gypsum,  B) at least 20 parts by mass of mineral filler, C) at 20 ° C solid organosilicon compound which is selected from Organosiliconatpulver Cl and  Organosilicon compounds C2 which can be prepared by reacting one molar equivalent of silane S, which is selected from hydrocarbyltrihalosilane,  Hydrocarbon tricarboxylic oxy-silane or  Mixtures thereof or their partial hydrolysates with  Polyhydroxy compounds P in such a molar ratio that per mole equivalent of halogen or  Hydrocarbonoxy radical 0.3 to 1.3 molar equivalents  Hydroxy radicals are present,  D) fatty acid compound selected from fatty acid Dl, fatty acid salt D2 and fatty acid ester D3. 2. gypsum dry mortar according to claim 1, in which the mineral filler B is selected from alkaline earth carbonates,  Alkaline earth sulfates, silica, silicates, aluminum, titanium, iron, or zinc oxides and their mixed oxides, and mixtures thereof. 3. gypsum dry mortar according to claim 1 or 2, to 100  Bulk gypsum 25 to 900 parts by mass of mineral  Contains filler B. , Plaster dry mortar after one or more of  preceding claims, wherein the Organosiliconatpulver Cl solid salts of organosilanols, of which Hydrolysis / condensation products, or of organosilanols together with their hydrolysis / condensation products with Alkali cations are those in which the molar ratio of cation to silicon is 0.5 to 3. Plaster dry mortar after one or more of preceding claims, which a  Organosilicon compound C2, which is prepared using a polyhydroxy compound P, which is selected from a linear or branched monomeric or oligomeric C2 -Cg glycol, and mixed glycols, from tri-, Tetra-, penta- and Hexahydroxyverbindungen having 3 to 12 carbon atoms, from C ₂ -Cx2 ^_H ydroxycarbonsäuren and Mixtures thereof. Plaster dry mortar after one or more of preceding claims, containing per 100 parts by mass of gypsum 0.02 to 4 parts by mass of organosilicon compound C. Plaster dry mortar after one or more of preceding claims, wherein the fatty acid salt D2 is selected from fatty acid salts of the alkali metals, alkaline earth metals and Group 12 metals Periodic table of the elements and mixtures thereof. Plaster dry mortar ^' according to one or more of preceding claims, wherein the fatty acid ester D3 is selected from alkyl esters of fatty acids of general formula RCOOR ', where R is a linear or branched, saturated or unsaturated, unsubstituted or substituted hydrocarbon radical having 4 to 22 carbon atoms, and R * is a linear or branched, saturated or unsaturated unsubstituted or substituted hydrocarbon radical having 1 to 50 carbon atoms, which is represented by a or a plurality of oxygen atoms may be interrupted, wherein in each case at least one carbon atom is located between two adjacent oxygen atoms and from mono-, di and triglycerides of saturated fatty acids and mixtures thereof. Plaster dry mortar after one or more of preceding claims containing from 0.01 to 3 parts by mass of fatty acid compound D per 100 parts by mass of gypsum.