WO2013020173A1 - Compositions hydrophobes pour du plâtre - Google Patents

Compositions hydrophobes pour du plâtre Download PDF

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Publication number
WO2013020173A1
WO2013020173A1 PCT/AU2012/000935 AU2012000935W WO2013020173A1 WO 2013020173 A1 WO2013020173 A1 WO 2013020173A1 AU 2012000935 W AU2012000935 W AU 2012000935W WO 2013020173 A1 WO2013020173 A1 WO 2013020173A1
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WO
WIPO (PCT)
Prior art keywords
plaster
sodium
water repellent
composition
silicate
Prior art date
Application number
PCT/AU2012/000935
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English (en)
Inventor
Franc Omahen
John Girvan THRUM
Original Assignee
Rapid Building Systems Pty Ltd
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Filing date
Publication date
Priority claimed from AU2011903215A external-priority patent/AU2011903215A0/en
Application filed by Rapid Building Systems Pty Ltd filed Critical Rapid Building Systems Pty Ltd
Publication of WO2013020173A1 publication Critical patent/WO2013020173A1/fr

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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
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/60—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only artificial stone
    • C04B41/61—Coating or impregnation
    • C04B41/62—Coating or impregnation with organic materials
    • C04B41/64—Compounds having one or more carbon-to-metal of carbon-to-silicon linkages
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
    • A61L15/07—Stiffening bandages
    • A61L15/08—Stiffening bandages containing inorganic materials, e.g. plaster of Paris
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
    • A61L15/07—Stiffening bandages
    • A61L15/12—Stiffening bandages containing macromolecular materials
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
    • A61L15/07—Stiffening bandages
    • A61L15/14—Use of materials characterised by their function or physical properties
    • 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
    • C04B28/14—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 calcium sulfate cements
    • C04B28/145—Calcium sulfate hemi-hydrate with a specific crystal form
    • 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
    • C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/0028—Aspects relating to the mixing step of the mortar preparation
    • C04B40/0039—Premixtures of ingredients
    • 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
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
    • 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
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
    • C04B41/46—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with organic materials
    • C04B41/49—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes
    • C04B41/4905—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes containing silicon
    • C04B41/495—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes containing silicon applied to the substrate as oligomers or polymers
    • C04B41/4961—Polyorganosiloxanes, i.e. polymers with a Si-O-Si-O-chain; "silicones"
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/24—Acids; Salts thereof
    • C08K3/26—Carbonates; Bicarbonates
    • 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
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00612—Uses not provided for elsewhere in C04B2111/00 as one or more layers of a layered structure
    • C04B2111/0062—Gypsum-paper board like materials
    • 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
    • C04B2111/27—Water resistance, i.e. waterproof or water-repellent materials

Definitions

  • the present invention relates to water repellent compositions for plaster and plaster products.
  • Plaster is used extensively in the building industry. For example, gypsum plaster
  • plaster (CaS0 4 - 1/2H 2 0; "plaster of Paris") is used in the production of building products including interior walling panels such as plasterboard (gypsum wallboard) and external walling panels such as the prefabricated panels produced by the present applicant under the tradename RapidwallTM.
  • interior walling panels such as plasterboard (gypsum wallboard)
  • external walling panels such as the prefabricated panels produced by the present applicant under the tradename RapidwallTM.
  • Other plasters such as lime plaster and cement plaster are also used.
  • plaster has excellent properties, such as high fire resistant properties, high sound-proof properties, and low price, it also has a disadvantage in that it has very little resistance to water.
  • Waxes have been used to decrease the amount of water absorbed by plaster products.
  • United States patent 2, 198,776 discloses the addition of finely powdered paraffin or a spray of molten paraffin to a plaster slurry.
  • it can be difficult to disperse waxes adequately in the finished plaster product.
  • polymeric silicon-based materials such as polysiloxanes have been used as substitutes for waxes.
  • United States patent 4,643,771 discloses the use of a polysiloxane as a water resistant additive in a plaster product.
  • Polysiloxanes have also been used in combination with other agents as water resistant additives.
  • United States patent 5,624,481 composition for rendering plaster water repellent comprising an organosiloxane containing Si-bonded hydrogen atoms and an alkali metal silicate.
  • International patent application WO 2007/027341 a composition comprising a H-polysiloxane and magnesia (MgO) for waterproofing gypsum.
  • MgO magnesia
  • compositions and methods that reduce the cost of producing water repellent plaster products.
  • compositions and methods that improve the water repellency of prior art water repellent additives for plaster products.
  • the present invention arises from our research into the use of water repellent polysiloxane additives for plaster products and, in particular, our surprising discovery that the addition of some inorganic carbonate and/or bicarbonate salts to polysiloxanes provides water repellent additives that are at least as water repellent as the starting polysiloxane but which require less polysiloxane to achieve the same level of water repellency.
  • the present invention provides a water repellent composition for plaster or plaster products, the composition comprising:
  • the water repellent plaster composition further comprises a metal silicate.
  • the metal silicate may be selected from the group consisting of potassium silicate and sodium silicate.
  • the metal silicate is sodium silicate.
  • the sodium silicate is sodium metasilicate (Na 2 Si0 3 ).
  • the sodium silicate is 'neutral' sodium silicate (about 3.2 Si0 2 to about 1 Na 2 0).
  • the sodium silicate is 'alkaline' sodium silicate (about 2 Si0 2 to about 1 Na 2 0).
  • the plaster slurry further comprises a metal silicate.
  • the metal silicate may be selected from the group consisting of a potassium silicate and a sodium silicate.
  • the metal silicate is sodium silicate.
  • the sodium silicate is sodium metasilicate (Na 2 Si(3 ⁇ 4).
  • the sodium silicate is 'neutral' sodium silicate (about 3.2 Si0 2 to about 1 Na 2 0).
  • the sodium silicate is 'alkaline' sodium silicate (about 2 Si0 2 to about 1 Na 2 0).
  • the present invention provides a process for the production of a water repellent plaster product, the process comprising combining:
  • the process further comprises combining a metal silicate with the polysiloxane and the carbonate or bicarbonate salt.
  • the metal silicate may be selected from the group consisting of a potassium silicate and a sodium silicate.
  • the metal silicate is sodium silicate.
  • the sodium silicate is sodium metasilicate (Na 2 Si0 3 ).
  • the sodium silicate is 'neutral' sodium silicate (about 3.2 S1O2 to about 1 Na 2 0).
  • the sodium silicate is 'alkaline' sodium silicate (about 2 Si0 2 to about 1 Na 2 0).
  • the carbonate or bicarbonate salt having a sodium, magnesium, ammonium or lithium counter ion is sodium bicarbonate.
  • the polysiloxane is a powder. In other embodiments, the polysiloxane is an aqueous solution.
  • Plaster products are generally manufactured by:
  • a gypsum slurry is poured onto a paper substrate and the slurry/substrate combination is then sized in a continuous process by passing it between rollers. Simultaneous with this sizing step, a paper backing is positioned over the sized gypsum slurry.
  • plaster is intended to include gypsum plaster (natural gypsum plaster, synthetic gypsum plasters, and desulphurised flue gas gypsums from coal, oil or gas or other fuel burning plants), lime plaster, and cement plaster.
  • gypsum plaster natural gypsum plaster, synthetic gypsum plasters, and desulphurised flue gas gypsums from coal, oil or gas or other fuel burning plants
  • lime plaster calcium plaster
  • cement plaster cement plaster
  • the term "plaster products” is intended to include plaster wall panels, plasterboard, plaster tile, plaster block, plaster casts, moulded plaster products, dry plaster mixes, etc. The terms also includes within its scope composites made using plaster, such as plaster fibre composites, glass fibre plaster products, plaster wood fibre products, etc. [0027] In a first aspect, the present invention provides a water repellent composition for plaster or plaster products, the composition comprising:
  • weight ratio of polysiloxane to carbonate or bicarbonate salt in the composition is from about 1 :0.1 to about 1 :5.
  • the composition of the present invention When the composition of the present invention is used in plaster products the maximum water absorption of the products is reduced as compared to products for which the water repellent composition is not used.
  • the water repellent composition described herein improves the water repellency characteristic of the products.
  • the water repellent composition ameliorates any detrimental effects that absorbed water can have on such products, including causing dimensional instability (swelling), loss of mechanical strength, and biological degradation.
  • the polysiloxane may be any polysiloxane that provides water repellent properties to gypsum products.
  • polysiloxane means an oligomeric or polymeric compound with repeating
  • R2S1O units where R is a hydrogen atom and/or a hydrocarbon group.
  • the hydrocarbon group may be an optionally substituted alkyl group, such as a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl moiety, or a structural isomer thereof.
  • the hydrocarbon group may be an optionally substituted cycloalkyl group, such as a cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl or cyclodecyl moiety, or a structural isomer thereof.
  • the hydrocarbon group may be an optionally substituted aryl group, such as a phenyl group, a tolyl group, a xylyl group, a benzyl group, a naphthyl group, an anthryl group or a phenanthryl group.
  • the hydrocarbon group may be substituted with one or more alkyl groups, cycloaryl groups, aryl groups or halogens. When more than one R substituent is present, each substituent may be the same or different.
  • Polysiloxanes containing methyl groups tend to have good water repellent properties. Polysiloxanes are also referred to as "silicones" and, as such, any reference to polysiloxanes herein should be taken as a reference to silicones.
  • the polysiloxane is a H-polysiloxane containing groups of the general formula:
  • - R is identical or different monovalent, unsubstituted or halogen-substituted C
  • polysiloxanes are available commercially.
  • Particularly suitable polysiloxanes are polyalkylhydrogensiloxanes and polyalkylsiliconate salts.
  • the polysiloxane is a polymethylhydrogensiloxane.
  • polymethylhydrogensiloxanes in the form of emulsions, and powders are available from Wacker Chemie AG.
  • Particularly suitable polysiloxanes include: SILRES® BS 46 which is an aqueous emulsion comprising polymethylhydrogensiloxane available from Wacker Chemie AG ; and SILRES® BS 94 which is a polymethylhydrogensiloxane available from Wacker Chemie AG.
  • Other suitable polysiloxanes include SILRES® BS 16 which is an aqueous solution of potassium methylsiliconate available from Wacker Chemie AG.
  • the polyalkylhydrogensiloxane is linear.
  • the hydrogen content of the polyalkylhydrogensiloxane is from 0.05% to 5.0% by weight.
  • the polysiloxane may be a solid, such as a powder, a solution, such as an aqueous solution, or an emulsion.
  • the polysiloxane is a powder.
  • the polysiloxane is in aqueous solution.
  • carbonate or bicarbonate salt having a sodium, magnesium, ammonium or lithium counter ion it is possible to use less polysiloxane to make plaster products water repellent. Whilst any of these carbonate or bicarbonate salts may be used, those having a sodium counter ion may be particularly suitable.
  • the carbonate or bicarbonate salt is sodium bicarbonate. We have found that sodium bicarbonate provides good water repellency under a range of conditions and on a range of plaster samples.
  • carbonate or bicarbonate salts are readily available commercially and, generally, at relatively low cost.
  • a waterproofing emulsion for masonry that comprises a hydrolysable siloxane, an organopolysiloxane resin, a silica filler, an emulsifier, a buffer, and a biocidal agent.
  • a small amount of sodium bicarbonate may be added to buffer the emulsion.
  • the role of the sodium bicarbonate in this case is to buffer the water and, as a result, relatively small amounts of sodium bicarbonate are added to the mixture.
  • the present Applicant's propose that the bicarbonate or carbonate salt used in the compositions disclosed herein is present in larger amounts and plays a role other than just buffering the aqueous solution. Indeed, the Applicants have found that the compositions described herein provide effective water repellency at a wide range of pH. ⁇
  • the weight ratio of polysiloxane to carbonate or bicarbonate salt in the composition is from about 1 :0.1 to about 1 :5. In embodiments, the weight ratio of polysiloxane to carbonate or bicarbonate salt in the composition is from about 1 :0.1 to about 1 :3. In embodiments, the weight ratio of polysiloxane to carbonate or bicarbonate salt in the composition is from about 1 : 1 to about 1 :3. In embodiments, the weight ratio of polysiloxane to carbonate or bicarbonate salt in the composition is from about 1 : 1.5 to about 1:2.5. In embodiments, the weight ratio of polysiloxane to carbonate or bicarbonate salt is about 1 :2. In other embodiments, the weight ratio of polysiloxane to carbonate or bicarbonate salt is about 1 :1.7.
  • the minimum amount of carbonate or bicarbonate salt in the plaster is 0.0009 % based on the weight of plaster. In embodiments, the minimum amount of carbonate or bicarbonate salt in the plaster is 0.01 % based on the weight of plaster. In embodiments, the minimum amount of carbonate or bicarbonate salt in the plaster is 0.05 % based on the weight of plaster. In embodiments, the minimum amount of carbonate or bicarbonate salt in the plaster is 0.2 % based on the weight of plaster. [0040] In embodiments, the maximum amount of carbonate or bicarbonate salt in the plaster is 2.0 % based on the weight of plaster. In embodiments, the maximum amount of carbonate or bicarbonate salt in the plaster is 0.8 % based on the weight of plaster. In embodiments, the maximum amount of carbonate or bicarbonate salt in the plaster is 0.5 % based on the weight of plaster.
  • the water repellency of the composition can be further increased by mixing with a metal silicate. Therefore, in embodiments the composition also comprises a metal silicate.
  • the metal silicate may be selected from the group consisting of potassium silicate and sodium silicate.
  • the metal silicate is sodium silicate.
  • sodium silicate refers to any one of several compounds containing sodium oxide (Na 2 0) and silica (Si 2 0) or a mixture of sodium silicates with varying ratios of Si0 2 to Na 2 0, solids contents, and viscosity.
  • the term “sodium silicate” includes within its scope (but is not limited to) sodium orthosilicate (Na 4 Si0 4 ); sodium metasilicate (Na 2 Si0 3 ); sodium disilicate (Na 2 Si 2 0s); sodium tetrasilicate (Na 2 Si 4 0 ). All these compounds are colourless, transparent, glasslike substances that are available commercially as powders or as viscous solutions in water. They are produced by fusing sand and sodium carbonate in various proportions. Thus, the sodium silicate is available commercially in several grades.
  • the metal silicate is sodium metasilicate.
  • Sodium metasilicate (Na 2 SiOj) is available commercially in the form of a white, odorless, granular and free flowing alkaline substance. It is produced by dissolving NaOH in hot alkaline sodium silicate solution followed by crystallisation in a crystalliser using powdered sodium metasilicate as a source of crystal nuclei.
  • the sodium metasilicate may be anhydrous (Na 2 SiOj; CAS No. 6834-92-0) or in the form of a pentahydrate (Na 2 SiCy 5H 2 0; CAS No.
  • Sodium metasilicate may also be referred to as: metso beads; silicic acid, disodium salt;
  • sodium-m-silicate orthosil; disodium metasilicate; disodium monosilicate; waterglass; or disodium trioxosilicate.
  • the composition may comprise sodium metasilicate in an amount of about 0.01% to about 0.2% by weight of plaster.
  • the composition comprises sodium metasilicate in an amount of about 0.1% by weight of plaster.
  • the sodium silicate is 'neutral' sodium silicate which is a viscous liquid formed with a ratio of about 3.2 Si0 2 to about 1 Na 2 0.
  • the composition may comprise 'neutral' sodium silicate in an amount of about 0.1% to about 2% by weight of plaster.
  • the composition comprises 'neutral' sodium silicate in an amount of about 2% by weight of plaster.
  • the sodium silicate is 'alkaline' sodium silicate which is a viscous liquid formed with a ratio of about 2 Si0 2 to about 1 Na 2 0.
  • the composition may comprise sodium silicate in an amount of about 0.1% to about 2% by weight of plaster.
  • the composition comprises 'alkaline' sodium silicate in an amount of about 2% by weight of plaster.
  • the water repellency of a plaster product can be measured using standard industry tests. For example, test plaster products of known mass may be stored in water for a predetermined time period, and then removed from the water and freed of any water adhering to the surface. The mass of the samples can then be determined and the water absorption calculated as a percentage by mass.
  • a standard that is used in the plaster industry is that the water absorption must be less than 5% after two hours submersion in water.
  • Using the water repellent compositions of the present invention we have found that the water absorption of plaster samples made with these compositions is between 0.5% and ⁇ 5% of water uptake after 24 hours. This represents a significant improvement on the industry standard.
  • the water absorption of plaster products incorporating the water repellent compositions of the present invention is less than 2% after 2 hours. In embodiments, the water absorption of plaster products incorporating the water repellent compositions of the present invention is less than 1% after 2 hours. In embodiments, the water absorption of plaster products incorporating the water repellent compositions of the present invention is less than 15% after 48 hours, preferably less than 10% after 48 hours, more preferably less than 5% after 48 hours.
  • Additives that aid in the production of plaster products and/or confer desirable characteristics on plaster or plaster products may optionally be added to the water repellent composition.
  • Suitable additives include chelators, set retarders, antioxidants, ultraviolet absorbers, plasticisers, fire retardants, accelerators, bonding agents, adhesive catalysts, dispersants, foaming agents, thickeners, fillers, pigments, dyes, colourants, preservatives, antimicrobial agents, etc.
  • Suitable additives may be inorganic or organic.
  • a chelator such as Dissolvine® (AkzoNobel) may be added.
  • fungicide such as zinc dimethyl dithiocarbamate, may be added.
  • a fire retardant such as borax boric acid
  • a filler such as silicon dioxide or cellulose fibres
  • an accelerator such as potassium sulfate or aluminium sulphate may be added.
  • a plasticiser such as a lignosulfonate or naphthalene sulphonate may be added.
  • a bonding agent for cardboard such as starch
  • a bonding agent for cardboard such as starch
  • a set retarder such as sodium citrate or a proteinaceous retarder, may be added.
  • the water repellent composition may be in the form of a solution, an emulsion or a powder. Solutions or emulsions may be formed in a suitable solvent. Typically, the solvent is water.
  • Emulsions may be formed by a mechanical emulsification method or a phase inversion emulsification method. These methods may be employed either independently or simultaneously.
  • the plaster may be any type of plaster or similar cementitious product.
  • the water repellent composition provides suitable water repellency to a range of plaster types which is not the case with some prior art water repellent compositions.
  • the plaster is gypsum.
  • the gypsum may be in the form of building plaster, stucco plaster, insulation plaster, screed plaster, marble plaster, anhydrite, alpha plaster, etc.
  • the water repellent composition may be added to a plaster slurry as a single composition or the polysiloxane and carbonate or bicarbonate salt having a sodium, magnesium, ammonium or lithium counter ion may be added separately.
  • the present invention therefore provides a plaster slurry useful in making a plaster product, the slurry comprising:
  • the plaster slurry may also comprise a metal silicate.
  • the metal silicate may be selected from the group consisting of potassium silicate and sodium silicate.
  • the metal silicate is sodium metasilicate (Na 2 Si0 3 ).
  • the metal silicate is sodium silicate.
  • the sodium silicate may be 'neutral' sodium silicate (3.2 Si0 2 to 1 Na 2 0) or 'alkaline' sodium silicate (2 Si0 2 to 1 Na 2 0).
  • the water repellent composition may be added to dry plaster and the dry mixture added to water to form a plaster slurry.
  • the water repellent composition may be added to the plaster slurry prior to formation of a solid plaster product therefrom.
  • the slurry may be used to produce a water repellent plaster product, the process comprising combining: (i) a polysiloxane; and
  • the water repellent composition may be especially useful when employed as a waterproof agent for plaster products such as gypsum boards and gypsum plaster, cements, paper, and fibres.
  • the slurry is formed into a solid product by processing the slurry to remove some of the water.
  • the remaining solids are then shaped into the desired form by casting, pouring, moulding, etc.
  • the shaped product is then dried to provide the plaster product.
  • the water can be removed mechanically and/or by heat treatment. We have found that neither the mechanical properties nor the setting time of plaster products are significantly affected by the inclusion of the water repellent composition in the plaster slurry.
  • the water repellent composition may be impregnated into a plaster product after shaping, after setting and/or after drying.
  • the water repellent composition may be applied by dipping, spraying or painting.
  • a plaster slurry was prepared from 100 parts by weight of Kilmore natural gypsum plaster (CaS0 4 .l/2 H 2 0), 65 parts by weight of water and 0.3 parts by weight of a water repellent composition comprising 0.3 parts by weight of polysiloxane (BS94) and 0.5 parts by weight sodium bicarbonate.
  • the slurry was stirred and then cast into moulds to give plaster products. After 1 hour, the solidified products were removed from the moulds and dried for 5 hours in a circulated air drying oven.
  • test specimens were immersed in a horizontal position in water at 15 to 25 °C so that the depth of water above the specimen surface was 10-20 mm. After storage in water for either 2 or 48 hours, the test specimens were taken from the water, the water adhering to the surface was removed and the increase in mass was determined by weighing. Test specimens exhibited 0.5% water absorption after 2 hours of immersion and 2.3% after 48 hours of immersion. In contrast, a test specimen made without the sodium bicarbonate would be expected to exhibit >6% water absorption after 2 hours and >18% after 48 hours.
  • Plaster products were prepared according to the method set out in Example 1 using the components listed in Table 1.
  • BS16 SILRES® BS 16 from Wacker Chemie AG
  • a plaster product was prepared from 100 parts by weight of Kilmore natural gypsum plaster, 72 parts by weight of water, 0.2 parts by weight of polysiloxane (BS94) and 1.0 parts by weight potassium bicarbonate as described in Example 1.
  • the water absorption of the product was determined as described in Example 1 and the results are shown in Table 5.

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Abstract

L'invention concerne une composition hydrophobe pour du plâtre ou des produits à base de plâtre, la composition comprenant : un polysiloxane ; et un sel carbonate ou bicarbonate ayant un contre-ion sodium, magnésium, ammonium ou lithium. Le rapport pondéral de polysiloxane au sel carbonate ou bicarbonate dans la composition est d'environ 1:0,1 à environ 1:5
PCT/AU2012/000935 2011-08-11 2012-08-08 Compositions hydrophobes pour du plâtre WO2013020173A1 (fr)

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AU2011903215A AU2011903215A0 (en) 2011-08-11 Water repellent plaster compositions
AU2011903215 2011-08-11

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105218155A (zh) * 2015-09-16 2016-01-06 桂林市和鑫防水装饰材料有限公司 一种液体渗透防水剂
CN105218153A (zh) * 2015-09-16 2016-01-06 桂林市和鑫防水装饰材料有限公司 一种新型渗透防水剂
WO2015164119A3 (fr) * 2014-04-25 2016-01-21 United States Gypsum Company Compositions de siloxane et procédés permettant de réduire la teneur en composés organiques volatils et la poussière de siloxane
US9410058B2 (en) 2014-04-10 2016-08-09 United States Gypsum Company Compositions and methods for water-resistant gypsum fiber products
IT201700044538A1 (it) * 2017-04-24 2018-10-24 Aurora S R L Additivo per vernici, stucchi, intonaci ed altri materiali destinati al rivestimento di superfici architettoniche
WO2020104000A1 (fr) * 2018-11-19 2020-05-28 Knauf Gips Kg Amélioration de la résistance à l'affaissement de plaques de plâtre imperméabilisées au moyen de polydiméthylsiloxanes
WO2021023320A1 (fr) * 2019-08-06 2021-02-11 First Point a.s. Composé de traitement de plâtre
CN115322601A (zh) * 2022-09-16 2022-11-11 上海迈方碳科技有限公司 一种防霉防潮石膏基石墨烯涂料及其制备方法
US20220380625A1 (en) * 2019-09-30 2022-12-01 Asahi Fr R&D Co., Ltd. Sliding member and method for manufacturing same

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB901882A (en) * 1959-05-29 1962-07-25 Polycell Prod Ltd Improvements in plaster compositions
GB979639A (en) * 1962-02-19 1965-01-06 Bayer Ag Building material compositions
CA735002A (en) * 1966-05-24 Weissbach Helmut Polysiloxane and lime or cement water repellant composition
US3318839A (en) * 1962-02-19 1967-05-09 Bayer Ag Building material compositions for the manufacture of water-repellent products
US3914476A (en) * 1972-05-23 1975-10-21 Wacker Chemie Gmbh Method for imparting water repellency to inorganic surfaces
GB1422739A (en) * 1970-10-29 1976-01-28 Dynamit Nobel Ag Method of improving the surface protection of porous surfaces of inorganic oxidic materials
CA998891A (en) * 1973-05-24 1976-10-26 Wacker-Chemie Gmbh Method for imparting water repellency to inorganic surfaces
US4877654A (en) * 1988-05-02 1989-10-31 Pcr, Inc. Buffered silane emulsions for rendering porous substrates water repellent
US5624481A (en) * 1994-06-01 1997-04-29 Wacker-Chemie Gmbh Process for the water-repellent impregnation of plaster
WO2008066746A2 (fr) * 2006-11-29 2008-06-05 Dow Corning Corporation Émulsions aqueuses de résines de silicone
US20080286474A1 (en) * 2005-07-15 2008-11-20 Pierre Maurice Chevalier Hydrophobing Minerals and Filler Materials

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA735002A (en) * 1966-05-24 Weissbach Helmut Polysiloxane and lime or cement water repellant composition
GB901882A (en) * 1959-05-29 1962-07-25 Polycell Prod Ltd Improvements in plaster compositions
GB979639A (en) * 1962-02-19 1965-01-06 Bayer Ag Building material compositions
US3318839A (en) * 1962-02-19 1967-05-09 Bayer Ag Building material compositions for the manufacture of water-repellent products
GB1422739A (en) * 1970-10-29 1976-01-28 Dynamit Nobel Ag Method of improving the surface protection of porous surfaces of inorganic oxidic materials
US3914476A (en) * 1972-05-23 1975-10-21 Wacker Chemie Gmbh Method for imparting water repellency to inorganic surfaces
CA998891A (en) * 1973-05-24 1976-10-26 Wacker-Chemie Gmbh Method for imparting water repellency to inorganic surfaces
US4877654A (en) * 1988-05-02 1989-10-31 Pcr, Inc. Buffered silane emulsions for rendering porous substrates water repellent
US5624481A (en) * 1994-06-01 1997-04-29 Wacker-Chemie Gmbh Process for the water-repellent impregnation of plaster
US20080286474A1 (en) * 2005-07-15 2008-11-20 Pierre Maurice Chevalier Hydrophobing Minerals and Filler Materials
WO2008066746A2 (fr) * 2006-11-29 2008-06-05 Dow Corning Corporation Émulsions aqueuses de résines de silicone

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9410058B2 (en) 2014-04-10 2016-08-09 United States Gypsum Company Compositions and methods for water-resistant gypsum fiber products
WO2015164119A3 (fr) * 2014-04-25 2016-01-21 United States Gypsum Company Compositions de siloxane et procédés permettant de réduire la teneur en composés organiques volatils et la poussière de siloxane
AU2015250109B2 (en) * 2014-04-25 2018-07-12 United States Gypsum Company Siloxane compositions and methods for reducing VOC and siloxane dust
US10232588B2 (en) 2014-04-25 2019-03-19 United States Gypsum Company Siloxane compositions and methods for reducing VOC and siloxane dust
CN105218155A (zh) * 2015-09-16 2016-01-06 桂林市和鑫防水装饰材料有限公司 一种液体渗透防水剂
CN105218153A (zh) * 2015-09-16 2016-01-06 桂林市和鑫防水装饰材料有限公司 一种新型渗透防水剂
EP3398999A1 (fr) * 2017-04-24 2018-11-07 Aurora S.r.l. Additif pour peintures, mastics, pansements et autres matériaux destiné à couvrir des surfaces architecturales
IT201700044538A1 (it) * 2017-04-24 2018-10-24 Aurora S R L Additivo per vernici, stucchi, intonaci ed altri materiali destinati al rivestimento di superfici architettoniche
WO2020104000A1 (fr) * 2018-11-19 2020-05-28 Knauf Gips Kg Amélioration de la résistance à l'affaissement de plaques de plâtre imperméabilisées au moyen de polydiméthylsiloxanes
CN112888665A (zh) * 2018-11-19 2021-06-01 可耐福石膏两合公司 使用聚二甲基硅氧烷的防水石膏板的抗下垂性的改进
WO2021023320A1 (fr) * 2019-08-06 2021-02-11 First Point a.s. Composé de traitement de plâtre
US20220380625A1 (en) * 2019-09-30 2022-12-01 Asahi Fr R&D Co., Ltd. Sliding member and method for manufacturing same
US11787973B2 (en) * 2019-09-30 2023-10-17 Asahi Fr R&D Co., Ltd. Sliding member and method for manufacturing same
CN115322601A (zh) * 2022-09-16 2022-11-11 上海迈方碳科技有限公司 一种防霉防潮石膏基石墨烯涂料及其制备方法

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