Classifications

• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B14/02—Granular materials, e.g. microballoons
  • C04B14/36—Inorganic materials not provided for in groups C04B14/022 and C04B14/04 - C04B14/34
  • C04B14/361—Soil, e.g. laterite
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B26/00—Compositions of mortars, concrete or artificial stone, containing only organic binders, e.g. polymer or resin concrete
  • C04B26/02—Macromolecular compounds
  • C04B26/04—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
  • C04B2103/0045—Polymers chosen for their physico-chemical characteristics
  • C04B2103/0057—Polymers chosen for their physico-chemical characteristics added as redispersable powders

Definitions

• the present invention relates to earth building materials which are modified with hydrophobic polymers, as well as a method for their production and a method for fastening floors.
• silt, sand, gravel, clay, clay or their mixtures are mainly clastic sediments that differ essentially in particle size.
• the particle size for silt is typically 0.002 to 0.06 mm, for sand typically 0.06 to 2 mm and for gravel typically 2 to 60 mm.
• clay particles are typically less than 0.02 mm in diameter.
• Clay is usually a clay or brown colored clay with the finest limonite (brown iron ore) with more or less abundant admixtures of silt, sand and gravel, which can contain admixtures of larger rock particles and organic components.
• a disadvantage of earth building materials is often their low cohesion and therefore their low mechanical strength and formability as well as their generally high water permeability. These properties result in poor durability and durability of the construction work carried out with it, especially under wet conditions. These disadvantages are more pronounced the lower the proportion of so-called cohesive soils such as clay or clay in the earth building materials.
• Earth building materials based on sand, gravel and / or grit i.e. earth building materials with a low proportion of cohesive soils, are particularly interesting for constructional construction reasons. In addition, they are easier to handle than cohesive soils and generally show no shrinkage or less shrinkage when drying than cohesive soils.
• SU-A-179 67 743 describes a binder for increasing the strength, water resistance and erosion resistance of sand, consisting of water, lignin sulfonate and tree resin.
• JP-A-60004587 describes the surface treatment of soils against erosion by spraying on dilute (meth) acrylate dispersions.
• DE-A-195 48 314 describes the increase in the surface strength of soils by applying an aqueous, the stickiness-increasing preparation, which contains polyvinyl acetate and a mixture of onocarboxylic acids, to the surface of the soils.
• JP-A-2283792 describes a composition of bentonite, clay, sand, a re-emulsifiable polymer powder, a water-soluble polymer powder and sodium silicate powder, which is hardened by tamping.
• DE 199 21 815 describes the use of polysulfide-free, aqueous polymer preparations as an additive to building materials based on clay or clay. The long-term durability of these building materials is not always satisfactory.
• the object of the present invention is to provide modified earth building materials, in particular modified earth building materials with a high proportion of sand and / or gravel, which have improved cohesion and ductility.
• the earth building materials should be suitable for constructive building measures or structures such as road substructure, dam and dyke construction, embankments, parking lot fortifications or landfill seals. It is also an improved one
• earth building materials in particular earth building materials with a high proportion of sand and / or gravel, which contain at least one uniformly distributed water-insoluble polymer.
• the present invention therefore relates to earth building materials containing
• All quantities relating to earth building materials refer to their solids content.
• the solids content of the earth building materials is determined by drying at 120 ° C. for 24 hours.
• All quantities which relate to the polymer contained according to the invention and any additives and auxiliaries contained in the polymer are calculated as a solid, unless stated otherwise.
• the solids contents of the polymers and any additives and auxiliaries contained therein are determined by drying at 120 ° C. to constant weight.
• Preferred mineral main components are sands and gravel.
• the main mineral constituents can also contain mineral binders, their proportion generally making up less than 20% by weight, based on 100% by weight, of the main mineral constituent.
• Typical mineral binders here are quicklime, clay and clay. Minor amounts (i.e. up to 2% by weight) of cement are also possible.
• the main mineral component of the earth building materials according to the invention preferably contains less than 20% by weight, in particular less than 15% by weight of quicklime (calcium oxide), less than 20% by weight, in particular less than 10% by weight of clay and / or clay , In preferred embodiments, the main mineral component is essentially free of cement.
• the earth building material In order to achieve sufficient strength of the earth building material, it is generally necessary that it be at least 1 part by weight, preferably at least 2 parts by weight and in particular at least Contains 3 parts by weight of water-insoluble, hydrophobic, film-forming polymer, based on 100 parts by weight of mineral constituents. As a rule, amounts above 50 parts by weight, based on 100 parts by weight of mineral constituents, will not be necessary.
• the earth building material preferably contains not more than 40 parts by weight, in particular not more than 30 parts by weight and particularly preferably not more than 15 parts by weight of water-insoluble, film-forming polymer, based on 100 parts by weight of mineral constituents.
• the water-insoluble, film-forming polymers used are known, commercially available or can be prepared by known methods.
• the polymers used according to the invention for modifying the earth building materials are film-forming. This is understood to mean that the polymer particles of the film-forming polymer melt at a temperature which is below the production, processing and / or drying temperature of the modified earth building materials to form a polymer film.
• the temperature above which film formation occurs is also referred to as the minimum film formation temperature (MFT).
• a uniform film formation of the polymer in the earth building materials is generally ensured when the glass transition temperature T g of the polymer is below 80 ° C., preferably below 50 ° C., in particular below 30 ° C. and particularly preferably below 25 ° C.
• the glass transition temperature here means the "mid point temperature” determined according to ASTM D3418-82 by differential thermal analysis (DSC) (see also Zosel, Mother und Lack 82 (1976), pp. 125-134 and DIN 53765).
• DSC differential thermal analysis
• the glass transition temperature of the polymer is at least -30 ° C., preferably at least -20 ° C., in particular at least _10 ° C. or -5 ° C.
• the glass transition temperature T g does not exceed a value of 50 ° C., in particular 30 ° C.
• the glass transition temperature of polymers which are composed of ethylenically unsaturated monomers can be controlled in a known manner via the monomer composition (TG Fox, Bull. Am.
• the glass transition temperature Tg of the polymer is in the range from -20 ° C to + 25 ° C, preferably -10 ° C to +20 ° C and in particular -5 ° C to + 15 ° C. Glass transition temperatures in this area are Partially, since they enable the polymer to be filmed well and thus advantageous mechanical properties of the earth building materials according to the invention without the earth building materials having to be dried or solidified or even “burnt” at elevated temperatures.
• the polymer used is hydrophobic.
• Such polymerates are characterized in that they are insoluble in water and their polymer films absorb only a small amount of water, i. below 40 g / 100 g of polymer film, in particular below 30 g / 100 g of polymer film.
• hydrophobic polymers are homo- or copolymers of (meth) acrylates, copolymers of at least 15 one (meth) acrylate and and at least one vinylaromatic, e.g. Styrene, copolymers of olefins and / or diolefins and vinyl aromatics, e.g. from butadiene and styrene, or copolymers from vinyl esters and olefins, e.g. Vinyl acetate and ethylene.
• vinylaromatic e.g. Styrene
• olefins and / or diolefins and vinyl aromatics e.g. from butadiene and styrene
• vinyl esters and olefins e.g. Vinyl acetate and ethylene.
• Preferred hydrophobic polymers are made up of ethylenically unsaturated monomers M, which generally have at least 80% by weight, in particular at least 90% by weight, of ethylenically unsaturated monomers A with a water solubility of ⁇ 60 g / 1 and in particular ⁇ 30 g / 1 (25 ° C and 1 bar), with up to
• the monomers A 25 30% by weight, e.g. 5 to 25% by weight of the monomers A can be replaced by acrylonitrile and / or methacrylonitrile.
• the monomers A also contain 0.5 to 20% by weight of monomers B different from the monomers A.
• all amounts of monomers in% by weight are based on 100% by weight of monomers M.
• Monomers A are generally simply ethylenically unsaturated or conjugated diolefins. Examples of monomers A are:
• esters of an ⁇ , ⁇ -ethylenically unsaturated C 3 -C 6 monocarbon 35 acid or C -C 8 dicarboxylic acid with a C 1 -C 8 alkanol are preferably esters of acrylic acid or methacrylic acid, such as methyl (eth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate Etc.; 40 vinyl aromatic compounds such as styrene, 4-chlorostyrene, 2-methylstyrene, etc .;
• Vinyl esters of aliphatic carboxylic acids with preferably 1 to 45 10 carbon atoms such as vinyl acetate, vinyl propiate, vinyl laurate, vinyl stearate, vinyl versatic acid, etc .; Olefins such as ethylene or propylene;
• conjugated diolefins such as butadiene or isoprene
• Preferred film-forming polymers are selected from the polymer classes I to IV listed below:
• copolymers which contain, as monomer A, styrene and at least one C ⁇ -C ⁇ 0 -alkyl ester of acrylic acid and optionally one or more C ⁇ -C ⁇ o-alkyl esters of methacrylic acid in copolymerized form;
• copolymers which contain, as monomer A, styrene and at least one conjugated diene and, if appropriate, (meth) acrylic acid esters of Ci-Cs-alkanols, acrylonitrile and / or methacrylonitrile in copolymerized form;
• copolymers which contain, as monomers A, methyl acrylate, at least one C 1 -C 0 -alkyl ester of acrylic acid and optionally a C 2 -C 8 -alkyl ester of methacrylic acid as copolymerized units;
• copolymers containing as monomer A at least one vinyl ester of an aliphatic carboxylic acid with 2 to 10 carbon atoms and at least one C 2 -Cg-01efin and optionally one or more C 1 -C 8 -alkyl esters of acrylic acid and / or Polymerized methacrylic acid included.
• Typical C ⁇ -C ⁇ o-alkyl esters of acrylic acid in the copolymers of classes I to IV are ethyl acrylate, n-butyl acrylate, tert-butyl acrylate, n-hexyl acrylate and 2-ethylhexyl acrylate.
• Typical copolymers of class I contain, as monomers A, 20 to 80% by weight and in particular 30 to 70% by weight of styrene and 20 to 80% by weight, in particular 30 to 70% by weight, of at least one C 1 -C 10 alkyl esters of acrylic acid such as n-butyl acrylate, ethyl acrylate or 2-ethylhexyl acrylate, each based on the total amount of
• Typical class II copolymers contain, as monomers A, in each case based on the total amount of monomers A, 30 to 85% by weight, preferably 40 to 80% by weight and particularly preferably 45 to 75% by weight of styrene and 15 to 70% by weight, preferably 20 to 60% by weight and particularly preferably 25 to 50% by weight of butadiene, 5 to 20% by weight of the abovementioned monomers A by (met) acrylic acid reesters of -CC 8 alkanols and / or may be replaced by acrylonitrile or methacrylonitrile.
• Typical class III copolymers contain, as monomers A, in each case based on the total amount of monomers A, 20 to 80% by weight, preferably 30 to 70% by weight of methyl methacrylate and at least one further, preferably one or two further monomers, selected from Acrylklareestern of C ⁇ -C ⁇ 0 alkanols, particularly n-butyl acrylate, 2-ethylhexyl acrylate and ethyl acrylate and optionally a methacrylic esters of a C 2 0 -C ⁇ alkanol in a total amount of 20 to 80 wt .-%, and preferably 30 to 70 parts by weight % polymerized.
• monomers A in each case based on the total amount of monomers A, 20 to 80% by weight, preferably 30 to 70% by weight of methyl methacrylate and at least one further, preferably one or two further monomers, selected from Acrylklareestern of C ⁇ -C ⁇ 0 alkanols,
• Typical class IV copolymers contain as monomers A, in each case based on the total amount of monomers A, 30 to
• the class I and II polymers are particularly suitable.
• monomers B which are different from the aforementioned monomers and are copolymerizable with the monomers A are suitable as monomers B.
• Such monomers are known to the person skilled in the art and are generally used to modify the properties of the polymer.
• Preferred monomers B are selected from monoethylenically unsaturated mono- and dicarboxylic acids having 3 to 8 carbon atoms, in particular acrylic acid, methacrylic acid, itaconic acid, their amides such as acrylamide and methacrylamide, their N-alkylolamides such as N-methylolacrylamide and N-methylolmethacrylamide, their hydroxy -C-C 4 alkyl esters such as 2-hydroxyethyl acrylate, 2- and 3-hydroxypropyl acrylate, 4-hydroxybutyl acrylate
• the proportion of monomers with acid groups is preferably not more than 10% by weight and in particular not more than
• the proportion of hydroxyalkyl esters and monomers with oligoalkylene oxide chains, if present, is preferably in the range from 0.1 to 20% by weight and in particular in the range from 1 up to 10% by weight, based on the monomers M.
• the proportion of the amides and N-alkylol amides, if present, is preferably in the range from 0.1 to 5% by weight.
• crosslinking monomers such as glycidyl ethers and esters, for example vinyl, allyl and methallyl glycidyl ethers, glycidyl acrylate and methacrylate, the diacetonylamides of the abovementioned ethylenically unsaturated carboxylic acids, for example diacetone (meth) acrylamide, and the esters of acetoacetic acid with the above-mentioned hydroxyalkyl esters of ethylenically unsaturated carboxylic acids, for example acetylacetoxyethyl (meth) acrylate.
• glycidyl ethers and esters for example vinyl, allyl and methallyl glycidyl ethers, glycidyl acrylate and methacrylate
• the diacetonylamides of the abovementioned ethylenically unsaturated carboxylic acids for example diacetone (meth
• monomers B there are also compounds which have two non-conjugated, ethylenically unsaturated bonds, for example the di- and oligoesters of polyhydric alcohols with ⁇ , ⁇ -monoethylenically unsaturated C 3 -C 1 -monocarboxylic acids such as alkylene glycol diacrylates and dimethacrylates, for example ethylene glycol diacrylate, 1, 3-butylene glycol diacrylate, 1, 4-butylene glycol diacrylate, propylene glycol diacrylate, as well as divinylbenzene, vinyl methacrylate, vinyl acrylate, allyl methacrylate, allylacrylate, diallylmaleate, diallylfumarate, methylenebisacrylamide, cyclopentadicyclidyl acrylate, trenyl (nyl) acrylate, tri-nadyl methylacrylate, n-tryl (nyl) acrylate, tri-nadyl
• the polymer is used in the form of fine particles.
• Finely divided polymers are understood to mean those whose weight-average particle diameter does not exceed 10 ⁇ m and in particular 2 ⁇ m.
• the weight-average particle diameter dso of the polymer particles is in the range from 100 to 2000 nm.
• the weight-average particle diameter dso is understood to be the particle diameter which is below 50% by weight of the polymer particles.
• the weight-average particle diameter of a polymer can be measured in a known manner on an aqueous Determine the dipsersion of the particles by quasi-elastic light scattering or by measurement in an ultracentrifuge.
• Polymers with such particle diameters are generally in the form of aqueous polymer dispersions or in the form of powders which can be obtained from these dispersions by evaporating the water.
• Polymers in the form of aqueous polymer dispersions in particular those which are obtainable by free radical aqueous emulsion polymerization of the abovementioned ethylenically unsaturated monomers, are therefore preferred for producing the earth building materials according to the invention.
• Polymer powders prepared therefrom and aqueous dispersions which are obtainable by redispersing the polymer powders in water are likewise preferred. Redispersible polymer powders, in particular redipergable polymer powders obtainable from aqueous dispersions, are very particularly preferred as polymers.
• the free-radical, aqueous emulsion polymerization of the monomers M takes place in the presence of at least one surface-active substance and at least one, preferably water-soluble initiator which initiates the free-radical polymerization, at temperatures preferably in the range from 20 to 120 ° C.
• Azo compounds, organic or inorganic peroxides, salts of peroxodisulfuric acid and redox initiator systems are suitable as initiators.
• a salt of peroxodisulfuric acid is preferably used, in particular a sodium, potassium or ammonium salt or a redox initiator system which contains hydrogen peroxide as the oxidizing agent or an organic peroxide such as tert-butyl hydroperoxide and a sulfur compound as the reducing agent which is selected in particular from Sodium bisulfite, sodium hydroxymethanesulfinate and the bisulfite adduct to acetone.
• Suitable surface-active substances are the emulsifiers and protective colloids customarily used for emulsion polymerization.
• Preferred emulsifiers are anionic and nonionic emulsifiers which, in contrast to the protective colloids, generally have a molecular weight below 2000 g / mol and in amounts of up to 0.2 to 10% by weight, preferably 0.5 to 5% by weight. %, based on the polymer in the dispersion or on the monomers M to be polymerized.
• the anionic emulsifiers include alkali and ammonium salts of alkyl sulfates (alkyl radical: C 8 -C 2 o), of sulfuric acid semi-esters of ethoxylated alkanols (EO grade: 2 to 50, alkyl radical: C 8 to C 20 ) and ethoxylated alkylphenols (EO- Grade: 3 to 50, alkyl radical:
• alkyl sulfonic acids alkyl radical: C 8 to C 2 o
• alkylarylsulfonic acids alkyl radical: C -C 2 o
• suitable anionic emulsifiers can be found in Houben-Weyl, Methods of Organic Chemistry, Volume XIV / 1, Macromolecular Substances, Georg-Thieme-Verlag, Stuttgart, 1961, p. 192-208.
• the anionic surface-active substances also include compounds of the general formula I
• R 1 and R 2 are hydrogen or linear or branched alkyl radicals having 6 to 18 carbon atoms and in particular having 6, 12 and 16 carbon atoms, where R 1 and R 2 are not both hydrogen at the same time.
• X and Y are preferably sodium, potassium or ammonium, with sodium being particularly preferred.
• Technical mixtures are frequently used which have a proportion of 50 to 90% by weight of the monoalkylated product, for example Dowfax® 2Al (Trademark of Dow Chemical Company).
• the compounds I are generally known, for example from US Pat. No. 4,269,749.
• Suitable nonionic emulsifiers are araliphatic or aliphatic nonionic emulsifiers, for example ethoxylated mono-, di- and trialkylphenols (EO grade: 3 to 50, alkyl radical: C 4 -C 9 ), ethoxylates of long-chain alcohols (EO grade: 3 to 50 , Alkyl radical: C 8 -C 36 ) and polyethylene oxide / polypropylene oxide block copolymers.
• Ethoxylates of long-chain alkanols are preferred, and particularly preferably those based on oxo alcohols and native alcohols with a linear or branched C 12 -C 8 -alkyl radical and a degree of ethoxylation of 8 to 50.
• Anionic emulsifiers in particular emulsifiers of the general formula I, or combinations of at least one anionic and one nonionic emulsifier are preferably used.
• polymers which contain at least one alkoxylated, preferably ethoxylated, nonionic emulsifier and / or at least one alkoxylated, preferably ethoxylated, anionic emulsifier, for example one of the abovementioned.
• the amount of these emulsifiers is preferably in the range from 0.1 to 3.5% by weight, particularly preferably 0.2 to 3% by weight, based on the total weight of all polymerized monomers.
• the alkoxylated emulsifier or the alkoxylated emulsifiers can be added after the preparation of the polymers or preferably used for their preparation. Depending on the type of soil used to manufacture the earth building materials, such alkoxylated emulsifiers can both improve the producibility and processing properties and increase the mechanical strength and reduce the shrinkage that may occur when the earth building materials dry or harden.
• G eauche protective colloids are, for example, polyvinyl alcohols, polymers S tärke- and cellulose derivatives containing carboxyl groups such as homo- and copolymers of acrylic acid and / or metha crylklare with comonomers such as styrene, olefins or hydroxyalkyl esters, or vinylpyrrolidone-containing homo- and copolymers.
• suitable protective colloids can be found in Houben-Weyl, Methods of Organic Chemistry, Volume XIV / 1, Macromolecular Substances, Georg-Thieme-Verlag, Stuttgart 1961, pp. 411-420. Mixtures of emulsifiers and / or protective colloids can also be used.
• the molecular weight of the polymers can be adjusted by adding regulators in a small amount, generally up to 2% by weight, based on the polymerizing monomers M.
• Organic thio compounds, allyl alcohols and aldehydes are particularly suitable as regulators.
• regulators are frequently used in an amount of 0.1 to 2% by weight, preferably organic thio compounds such as tert-dodecyl mercaptan.
• the emulsion polymerization can be carried out either continuously or according to the batch procedure, preferably according to a semi-continuous process.
• the monomers to be polymerized can be fed continuously to the polymerization batch, including step or gradient procedures.
• the monomers can be fed to the polymerization both as a monomer mixture and as an aqueous monomer emulsion.
• the emulsion polymerization can be carried out by the seed latex process or in the presence of seed latex prepared in situ to set a defined polymer particle size. Methods for this are known and can be found in the prior art (see EP-B 40419 and Encyclopedia of Polymer Science and Technology, Vol. 5, John Willey & Sons Inc., New York 1966, p. 847).
• aqueous polymer dispersions Following the actual polymerization reaction, it may be necessary to make the aqueous polymer dispersions according to the invention largely free of odorants, such as residual monomers and other organic volatile constituents.
• This can be achieved physically in a manner known per se by removal by distillation (in particular by steam distillation) or by stripping with an inert gas.
• the lowering of the residual monomers can furthermore be carried out chemically by radical postpolymerization, in particular under the action of redox initiator systems, as are listed, for example, in DE _A 44 35 423, DE-A 44 19 518 and DE-A 44 35 422.
• the postpolymerization is preferably carried out using a redox initiator system composed of at least one organic peroxide and one organic sulfite.
• the polymer dispersions used are frequently made alkaline before being used according to the invention, preferably to pH values in the range from 7 to 10.
• Ammonia or organic amines can be used for neutralization uses, and preferably hydroxides, such as sodium hydroxide or calcium hydroxide are used.
• the aqueous polymer dispersions are subjected to a drying process in a known manner, preferably in the presence of customary drying aids.
• Spray drying is the preferred drying method.
• the drying aid is used in an amount of 1 to 30% by weight, preferably 2 to 20% by weight, based on the polymer content of the dispersion to be dried.
• the solids content of the polymer dispersion to be dried which already contains the drying aid (s), is generally in the range from 10 to 60% by weight, preferably in the range from 20 to 55% by weight (in each case calculated as polymer + drying aid, based on the total weight of the dispersion).
• the polymer dispersions to be dried are dried in the presence of the drying aid in a drying oven through which a stream of warm air is passed.
• the temperature of the hot air stream is generally 100 to 200 ° C., preferably 110 to 170 ° C. at the entrance to the drying tower, and about 30 to 100 ° C., preferably 50 to 80 ° C. at the tower exit.
• the polymer dispersion to be dried can be introduced against the hot air stream or, preferably, in parallel into the hot air stream. It can be added via single or multi-component nozzles or via a rotating disc.
• the polymer powder is deposited in a customary manner, for. B. using cyclones or filter separators.
• drying aids e.g. B. Homopolymers and copolymers of vinylpyrrolidone, homopolymers and copolymers of acrylic acid and / or methacrylic acid with monomers bearing hydroxyl groups, vinylaromatic monomers, olefins and / or (meth) acrylic esters, polyvinyl alcohol and in particular arylsulfonic acid-formaldehyde con sealing products and mixtures thereof.
• the drying agents can be added during the drying process in the form of solutions, for example as aqueous or aqueous-alcoholic solutions, to the polymer dispersion to be dried.
• the drying aid is preferably added to the polymer dispersion before drying.
• the drying agent can be used both as a solid or preferably as a solution, e.g. B. be added to the dispersion as an aqueous-alcoholic solution or in particular as an aqueous solution. It is also possible to use some of the drying aids in question as protective colloids during the preparation of the aqueous polymer dispersion (see above).
• Preferred drying aids are arylsulfonic acid-formaldehyde condensation products and their salts, preferably the substances described in WO 98/03577.
• An anticaking agent can also be added to the polymer dispersion to be dried during the drying process.
• This is a fine-particle inorganic oxide, for example a fine-particle silica or a fine-particle silicate, for example talc.
• the finely divided inorganic oxide preferably has an average particle size in the range from 0.01 to 0.5 ⁇ m. Finely divided silica with an average particle size in the range from 0.01 to 0.5 ⁇ m, which can be both hydrophilic and hydrophobic, is particularly preferred.
• the anti-caking agent can be added before or during the drying of the P olymerisatdispersion. In another embodiment, the anti-caking agent is added to the polymer powder in a mixing device suitable for solids, for example a vibrator, wheelchair screw mixer or the like.
• the anti-caking agent is used in an amount of 0.5 to 15% by weight and preferably in an amount of 2 to 12% by weight, based on the polymer powder (or on the total amount of polymer P + drying aid in the aqueous polymer dispersion).
• the earth building materials according to the invention may contain minor amounts of other polymers different from the abovementioned polymers, for example hydrophobic natural polymers and / or hydrophilic synthetic polymers, such as water-soluble polymers and so-called superabsorbent polymers or superabsorbers.
• the proportion of such polymers is generally below 5% by weight, preferably below 2% by weight, based on the content of mineral constituents.
• the earth building materials are free or essentially free of those polymers other than the hydrophobic synthetic polymers.
• the earth building materials according to the invention typically comprise
• Other natural organic and / or mineral earth constituents include, in particular, organic materials different from the earth constituents mentioned above, such as vegetable residues, humus, grass, straw, pieces of wood, wood and / or cork residues and inorganic materials such as silt, expanded shale, perlite and / or to understand expanded clay.
• the earth building materials according to the invention are generally produced by simply mixing soils, soils, sands and / or gravel, which represent or contain the main mineral components, with the polymer, preferably either in the form of a polymer dispersion or particularly preferably in the form of a polymer powder ,
• the mixing process is advantageously carried out until the polymer is uniformly or substantially uniformly distributed in the earth building material.
• Uniform distribution here means that there are as few local concentration islands of polymer or earth components as possible and that there is no noticeable concentration gradient in any spatial direction of the earth building materials.
• the water content of the polymer-modified earth building material before drying, curing or solidifying in the range from 1% by weight to 30% by weight, preferably 2% by weight to 20% by weight. -% and in particular 3 to 15 wt .-%, for example about 5 wt .-%, about 7 wt .-% or about 10 wt .-%.
• the water content in the polymer-modified earth building materials can, if desired, be adjusted to the above-mentioned values by adjusting the water content of one or more of the components, ie by drying or adding water.
• the adjustment of the water content in the polymer-modified earth building materials can be done before the components are mixed, during the mixing of the components. ten and after the mixing of the components, preferably before or during the mixing.
• the drying, hardening or solidification of the earth building materials according to the invention is generally carried out by themselves in the air or by heating to a temperature of up to 150 ° C., preferably up to 120 ° C. At temperatures below 10 ° C, the drying process is usually undesirably slow. In many cases the drying takes place in the range of the roughness temperature (15 to 30 ° C) for cost reasons.
• the present invention therefore also relates to a process for producing the earth building materials according to the invention, in which
• the mass obtained in this way is usually either mouldable or flowable and can be used directly for the desired use. If necessary, the still moist mass can also be compacted.
• Typical areas of application for the earth building materials according to the invention are the structural construction measures, for example the consolidation of road substructures, the use in dam and dike construction, the use in landfill seals or in the sealing and fastening of surfaces which are exposed to mechanical stress, such as embankments or parking spaces.
• the present invention therefore also relates to a method for fastening soils, in which the soil to be fastened is excavated or dredged, the soil thus obtained is optionally comminuted, mixed with at least one hydrophobic polymer and mixed until the polymer is uniformly distributed in the excavated material, when mixing, the water content of the mixture is adjusted to a value in the range from 1 to 30% by weight, preferably 2 to 20% by weight and in particular 3 to 15% by weight, and the mixture thus obtained, ie the invented applies earth building material again.
• the method described above is particularly suitable for the dam and Dike construction, landfill seals and generally to prevent or slow down undesirable erosion.
• the earth building materials according to the invention can be processed to shaped articles, in particular building blocks or earth bricks. Suitable processes for the production of moldings from mineral materials such as the earth building materials according to the invention are known to the person skilled in the art.
• the solidified or hardened earth building materials according to the invention are distinguished by significantly increased bending tensile and compressive strengths and by increased elasticities compared to unmodified clay moldings.
• the shrinkage which is usually observed when drying moist masses based on clastic sediments is generally not influenced or only insignificantly adversely affected by the earth building materials according to the invention, the shrinkage usually occurring to size and thus being of subordinate importance for the construction projects constructed using the earth building materials according to the invention ,
• Polymer Pl was used in the form of a 50% by weight aqueous polymer dispersion which was mixed with 1% by weight of ethoxylated C 3 -fatty alcohol (E08) and 1.5% by weight of the sodium salt of a sulfuric acid half-ester of ethoxylated C ⁇ 2 alcohol ( E03) was stabilized.
• the polymer dispersion had a minimum film-forming temperature of 16 ° C.
• the dispersion contained 0.4% by weight of nonylphenol ethoxylate (ethoxylation degree of severity 25) and 1.2% by weight of the sodium salt of the nonylphenol ethoxylate sulfuric acid half-ester (degree of ethoxylation 25).
• test specimens according to the invention from examples B1 and B2 were dimensionally stable both before and after the water storage, the test specimens from the comparative examples VBL and VB2 could not be handled undamaged either before or after the water storage.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Structural Engineering (AREA)
• Organic Chemistry (AREA)
• Materials Engineering (AREA)
• Civil Engineering (AREA)
• Inorganic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Curing Cements, Concrete, And Artificial Stone (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Soil Conditioners And Soil-Stabilizing Materials (AREA)
• Road Paving Structures (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=7667348

Family Applications (1)

Country Status (6)

Families Citing this family (13)

Family Cites Families (16)

• 2000
  • 2000-12-15 DE DE10062657A patent/DE10062657A1/de not_active Withdrawn
• 2001
  • 2001-12-14 CN CNA018206077A patent/CN1481344A/zh active Pending
  • 2001-12-14 US US10/450,657 patent/US20040047694A1/en not_active Abandoned
  • 2001-12-14 WO PCT/EP2001/014740 patent/WO2002048068A1/de not_active Application Discontinuation
  • 2001-12-14 JP JP2002549606A patent/JP2004523605A/ja not_active Withdrawn
  • 2001-12-14 EP EP01270506A patent/EP1341733A1/de not_active Withdrawn

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events