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
  • C04B16/00—Use of organic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of organic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B16/04—Macromolecular compounds
  • C04B16/08—Macromolecular compounds porous, e.g. expanded polystyrene beads or microballoons
• • 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
  • C04B16/00—Use of organic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of organic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B16/04—Macromolecular compounds
  • C04B16/08—Macromolecular compounds porous, e.g. expanded polystyrene beads or microballoons
  • C04B16/082—Macromolecular compounds porous, e.g. expanded polystyrene beads or microballoons other than polystyrene based, e.g. polyurethane foam
• • 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
  • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
  • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
• • 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
  • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
  • C04B2111/00241—Physical properties of the materials not provided for elsewhere in C04B2111/00
  • C04B2111/00405—Materials with a gradually increasing or decreasing concentration of ingredients or property from one layer to another
• • 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
  • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
  • C04B2111/20—Resistance against chemical, physical or biological attack
  • C04B2111/29—Frost-thaw resistance
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/249921—Web or sheet containing structurally defined element or component
  • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
  • Y10T428/249967—Inorganic matrix in void-containing component
  • Y10T428/249968—Of hydraulic-setting material
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/25—Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
  • Y10T428/254—Polymeric or resinous material
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
  • Y10T428/2991—Coated
  • Y10T428/2998—Coated including synthetic resin or polymer

Definitions

• the present invention relates to the use of polymeric microparticles in hydraulically setting building material mixtures to improve their Frostg. Freeze-thaw resistance.
• the concrete has two time-dependent properties. First, it experiences a decrease in volume due to dehydration, which is called shrinkage. However, most of the water is bound as water of crystallization. Concrete does not dry, it binds, that is, the initially low-viscosity cement paste (cement and water) stiffens, solidifies and finally solidifies, depending on the timing and sequence of the chemical-mineralogical reaction of the cement with the water, the hydration. Due to the water-binding capacity of the cement, the concrete, in contrast to calcined lime, can also harden under water and remain firm. Second, concrete deforms under load, the so-called creep.
• the frost-thaw cycle refers to the climatic change of temperatures around the freezing point of water.
• the frost-thaw cycle is a damaging mechanism. These materials have a porous, capillary structure and are not waterproof. Will one, soaked in water Structure exposed to temperatures below 0 C, so the water freezes in the pores. Due to the density anomaly of the water, the ice now expands. This leads to damage to the building material. In the very fine pores due to surface effects, the freezing point is lowered. In micro pores, water only freezes below -M 0 C. Since the material itself also expands and contracts due to freeze-thaw cycles, there is an additional capillary pumping effect that further increases water absorption and thus indirectly the damage. The number of freeze-thaw cycles is therefore decisive for the damage.
• the structure of a cement-bound concrete is traversed by capillary pores (radius: 2 ⁇ m - 2 mm) or gel pores (radius: 2 - 50 nm). Pore water contained therein differs in its state form depending on the pore diameter.
• a prerequisite for an improved resistance of the concrete during frost and thaw changes is that the distance of each point in the cement stone from the next artificial air pore does not exceed a certain value. This distance is also referred to as the "distance factor” or “powers spacing factor” [TCPowers, The air requirement of frost-resistant concrete, "Proceedings of the Highway Research Board” 29 (1949) 184-202]. Laboratory tests have shown that exceeding the critical "Power spacing factor" of 500 ⁇ m results in damage to the concrete in frosty conditions. and thaw changes. Therefore, in order to achieve this with limited air pore content, the diameter of the artificially introduced air pores must be smaller than 200-300 ⁇ m [K.Snyder, K. Natesaiyer & K.Hover, The Static and Statistical Properties of Entrained Air voids in Concrete: A mathematical basis for air void system characterization) "Materials Science of Concrete” VI (2001) 129-214].
• an artificial air pore system depends largely on the composition and grain size of the aggregates, the type and amount of cement, the concrete consistency, the mixer used, the mixing time, the temperature, but also on the type and amount of the air entraining agent. Under consideration of the appropriate manufacturing rules, their effects can indeed be mastered, however, there may be a large number of undesired impairments, which ultimately leads to the desired air content in the concrete can be exceeded or fallen below and thus adversely affected the strength or frost resistance of the concrete ,
• Such artificial air pores can not be dosed directly, but by the addition of so-called air entraining agents, the air introduced by the mixing is stabilized [L. Du & K.J. Folliard, Mechanism of air entrainment in concrete "Cement & Concrete Research” 35 (2005) 1463-71].
• Conventional air entraining agents are mostly of a surfactant-like structure and break the air introduced by the mixing into small air bubbles with a diameter as small as possible of 300 ⁇ m and stabilize them in the moist concrete structure. One distinguishes between two types.
• the other type e.g. Sodium lauryl sulfate (SDS) or sodium dodecyl phenylsulfonate - on the other hand forms with calcium hydroxide soluble calcium salts, but show an abnormal solution behavior. Below a certain critical temperature these surfactants show a very low solubility, above this temperature they are very soluble. By preferentially accumulating at the air-water interface, they also reduce the surface tension, thus stabilizing the microbubbles, and are preferably found on the surfaces of these air voids in the hardened concrete.
• SDS Sodium lauryl sulfate
• sodium dodecyl phenylsulfonate forms with calcium hydroxide soluble calcium salts, but show an abnormal solution behavior. Below a certain critical temperature these surfactants show a very low solubility, above this temperature they are very soluble.
• microparticles described therein have diameters of at least 10 microns (usually much larger) and have air or gas-filled cavities. This also includes porous Particles, which can be greater than 100 microns and can have a variety of smaller cavities and / or pores.
• the present invention was therefore based on the object to provide a means for improving the frost or freeze-thaw resistance for hydraulically setting building material mixtures, which develops its full effectiveness even at relatively low dosages.
• the task was also to achieve a high efficiency of this agent in order to achieve a corresponding effectiveness with the smallest possible amounts thereof; Lezteres is necessary in order not to excessively increase the manufacturing cost of a suitably equipped building material mixture
• Another task was to let the effect of this agent occur as soon as possible after processing and hardening of the building material mixture.
• the object is achieved by the use of polymeric microparticles having a cavity in hydraulically setting building material mixtures, characterized in that the shell of the microparticles contains crosslinkers and / or that the shell contains a plasticizer and / or that the monomer composition from the core to the shell in Steps or in the form of a gradient changes.
• Microparticles which fulfill one or more of these design criteria according to the invention can be produced with a very thin shell. Used as an additive in building material mixtures such microparticles have a high Effectiveness and lead even in small quantities to the desired resistance to frost or frost / thaw change.
• the shells of the microparticles according to the invention are on average preferably thinner than 140 nm; more preferred are shells which are thinner than 100 nm; most preferred are shells which are thinner than 70 nm.
• the determination of the average shell thickness is expediently carried out by measuring a statistically significant amount of particles on the basis of transmission electron micrographs.
• microparticles with thin shells can absorb and release the water very quickly.
• the hardening of the concrete, the frost or freeze-thaw resistance is made much faster.
• the amounts of crosslinker preferably used for the preparation of the microparticles according to the invention are from 0.3 to 15% by weight (based on the total amount of monomers in the shell); more preferred are 0.5-8% by weight of crosslinker; most preferred are 0.8-3% by weight.
• crosslinkers selected from the group consisting of ethylene glycol (meth) acrylate, propylene glycol (meth) acrylate, allyl (meth) acrylate, divinylbenzene, diallyl maleate, trimethylolpropane trimethacrylate, glycerol dimethacrylate, glycerol trimethacrylate, pentaerythritol tetramethacrylate or mixtures thereof.
• crosslinker which does not necessarily lead to the crosslinking of the shell polymer, but rather only one Increasing the molecular weight, it is possible to produce shells, which have sufficient strength even at a lower thickness to remain intact during the swelling of the microparticles. At the same time, fewer particles are observed in the shell when crosslinkers are used, which have sunk after swelling, similar to a slack football cover.
• the microparticles according to the invention may contain plasticizers in the shell.
• these particles by emulsion polymerization are preferably 0.3 to 12 wt% (based on the total weight of the shell as 100%) added together with the monomer mixture of the shell in the reactor so that they already during the polymerization and thus the structure the shell are present.
• the preferred amount of plasticizer may also be added after the polymerization but before swelling.
• plasticizer based on the total weight of the shell as 100%; most preferably 1 to 3% by weight of plasticizer.
• the plasticizers provide a tough and flexible shell that allows complete swelling of the microparticles. In this way, also very thin shells can be achieved.
• plasticizers selected from the group of phthalates, adipates, phosphates or citrates; phthalates being particularly preferred.
• the following plasticizers may be mentioned in particular, the list being further extendable and not meant to be limiting:
• Esters of phthalic acid e.g. Diundecyl phthalate, diisodecyl phthalate, diisononyl phthalate, dioctyl phthalate, diethylhexyl phthalate, di-C7-C11 n-alkyl phthalate, dibutyl phthalate, diisobutyl phthalate, dicyclohexyl phthalate, dimethyl phthalate, diethyl phthalate, benzyloctyl phthalate, butyl benzyl phthalate, dibenzyl phthalate and tricresyl phosphate, dihexyl dicapryl phthalate.
• Hydroxycarboxylic acid esters e.g. Esters of citric acid (for example, tributyl-O-acetyl citrate, triethyl O-acetyl citrate), esters of tartaric acid or esters of lactic acid.
• citric acid for example, tributyl-O-acetyl citrate, triethyl O-acetyl citrate
• esters of tartaric acid or esters of lactic acid for example, tributyl-O-acetyl citrate, triethyl O-acetyl citrate
• Aliphatic dicarboxylic acid esters e.g. Esters of adipic acid (for example dioctyl adipate, diisodecyl adipate), esters of sebacic acid (for example dibutyl sebacate, dioctyl sebacate, bis (2-ethylhexyl) sebacate) or esters of azelaic acid.
• adipic acid for example dioctyl adipate, diisodecyl adipate
• esters of sebacic acid for example dibutyl sebacate, dioctyl sebacate, bis (2-ethylhexyl) sebacate
• esters of azelaic acid for example dibutyl sebacate, dioctyl sebacate, bis (2-ethylhexyl) sebacate
• Esters of trimellitic acid e.g. Tris (2-ethylhexyl) trimellitate.
• Esters of benzoic acid e.g. benzyl benzoate
• Esters of phosphoric acid e.g. Tricresyl phosphate, triphenyl phosphate, diphenyl cresyl phosphate, diphenyl octyl phosphate, tris (2-ethylhexyl) phosphate, tris (2-butoxyethyl) phosphate.
• plasticizers can be used alone or as mixtures.
• the monomer composition of the core and the shell does not change abruptly, such as this is the case with an ideally designed core / shell particle, but gradually in two or more steps or in the form of a gradient.
• a gradient corresponds to a very large number of shells.
• a decreasing polymer content corresponds to a thinner wall with the same particle diameter.
• polymeric microparticles are used, the cavity of which is filled with 1 to 100% by volume, in particular 10 to 100% by volume, of water.
• the microparticles used consist of polymer particles which have a core (A) and at least one shell (B), the core / shell polymer particles having been swollen with the aid of a base.
• the core (A) of the particle contains one or more ethylenically unsaturated carboxylic acid (derivative) monomers which allow swelling of the core; these monomers are preferably selected from the group of acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid and crotonic acid and mixtures thereof. Acrylic acid and methacrylic acid are particularly preferred.
• Styrene, butadiene, vinyltoluene, ethylene, vinyl acetate, vinyl chloride, vinylidene chloride, acrylonitrile, acrylamide, methacrylamide, C1-C12-alkyl esters of acrylic or methacrylic acid are used in particular as nonionic, ethylenically unsaturated monomers which form the polymer shell (B) ,
• core-shell particles which are constructed mono- or multi-shell, or their shells have a gradient, according to the invention particularly thin shells are produced.
• the monomer composition gradually changes from the core to the shell in 2 or more steps or in the form of a gradient.
• the microparticles used according to the invention have a preferred average particle size of 100 to 5000 nm.
• the polymer content of Depending on the diameter and the water content, the microparticles used can be from 2 to 98% by weight (weight of polymer based on the total mass of the water-filled particle).
• diameters of 200 to 2000 nm are particularly preferred.
• particle sizes of 250 to 1000 nm are particularly preferred.
• the most preferred polymer contents are from 2 to 98% by weight, preferably from 2 to 60% by weight, most preferred are polymer contents from 2 to 40% by weight.
• microparticles for example of the ROPAQUE® type
• the commercially available microparticles are generally in the form of an aqueous dispersion which must contain a certain amount of dispersing agent of surfactant structure in order to suppress agglomeration of the microparticles.
• dispersions of these microparticles which have no surface-active (and possibly interfering in the concrete) surfactants.
• the microparticles are dispersed in aqueous solutions which have a theological adjusting agent.
• Such thickening agents which have a pseudoplastic viscosity, are mostly polysaccharidic in nature [D.B.Braun & M.R.Rosen, "Rheology Modifiers Handbook” (2000), William Andrew Publ.].
• Microbial exopolysaccharides of the gellan group (S-60) and, in particular, welan (S-130) and diutane (S-657) are eminently suitable [EJLee & R. Chandrasekaran, X-ray and computer modeling studies on gellan-related polymers: Molecular structures of welan, S-657, and rhamsan, "Carbohydrate Research” 214 (1991) 11-24].
• the water-filled, polymeric microparticles are used in the form of an aqueous dispersion.
• the water-filled microparticles directly as a solid of the building material mixture admit.
• the microparticles are - as described above - coagulated and isolated by conventional methods (eg, filtration, centrifugation, sedimentation and decanting) from the aqueous dispersion and the particles are then dried, whereby the hydrous core can be retained.
• washing the coagulated material with volatile liquids may be helpful.
• alcohols such as MeOH or EtOH have proven successful in the ROPAQU E® grades with their (poly) styrene shell.
• the water-filled microparticles are added to the building material mixture in a preferred amount of 0.01 to 5% by volume, in particular 0.1 to 0.5% by volume.
• the building material mixture for example.
• the usual hydraulically setting binder such as cement, lime, gypsum or anhydrite.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Materials Engineering (AREA)
• Structural Engineering (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Inorganic Chemistry (AREA)
• Curing Cements, Concrete, And Artificial Stone (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 2006
  • 2006-02-23 DE DE200610008969 patent/DE102006008969A1/de not_active Withdrawn
  • 2006-03-24 US US11/387,812 patent/US20070197671A1/en not_active Abandoned
  • 2006-05-10 CN CNA2006100817499A patent/CN101024561A/zh active Pending
• 2007
  • 2007-01-30 JP JP2008555735A patent/JP2009527450A/ja active Pending
  • 2007-01-30 BR BRPI0708241-0A patent/BRPI0708241A2/pt not_active Application Discontinuation
  • 2007-01-30 RU RU2008137547/03A patent/RU2008137547A/ru unknown
  • 2007-01-30 EP EP07704255A patent/EP2021299A2/de not_active Withdrawn
  • 2007-01-30 WO PCT/EP2007/050910 patent/WO2007096237A2/de not_active Ceased
  • 2007-01-30 KR KR1020087020706A patent/KR20080112205A/ko not_active Withdrawn
  • 2007-01-30 CA CA 2642996 patent/CA2642996A1/en not_active Abandoned

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