Leveling and sound reduction composition and method

Abstract

A floor underlayment composition includes a hydraulic binder in an amount of about 15-30 wt. %, and a filler in an amount of about 20-35 wt. %, wherein the filler includes rubber particles having a particle size of 0.5 mm or less, and wherein the composition has a flow rate of at least 200 mm.

Description

LEVELING AND SOUND REDUCTION COMPOSITION AND METHODFIELD OF THE TECHNOLOGY

[0001] The present technology relates to a leveling and sound reduction composition and method for use in the construction industry. In particular, the present technology relates to a leveling and sound reduction composition and method that includes hydraulic binder, rubber particles fdler and dispersible polymer components, and has improved sounddampening and absorption performance.BACKGROUND

[0002] It is known to cover substrates, such as, e.g., floors, with various types of coverings, such as e.g., tiles, linoleum, wood blocks, carpeting, polyvinyl chloride and rubber sheets. For the covering to have a useful life, it is necessary that the substrate to be covered is flat.

[0003] Self-levelling mixes based on hydraulic cement binders, i.e., mixes which will flow and thus take up a true horizontal surface level prior to setting, are known. The principal components of such mixes are sand and cement (to give hardening) and casein (which gives the self-levelling properties). The cement component of a self-levelling mix is usually a mixture of Portland cement and high alumina cement. It has been customaiy to use a major proportion of Portland cement for economy reasons, as well as because otherwise the mix sets too fast to be workable. It has been customary to keep the content of high alumina cement below 20% by weight. The content of high alumina cement can be critical and varies dependent on the activity of the high alumina cement. This is a drawback since it makes manufacture of a consistent product difficult.

[0004] Furthermore, in buildings or facilities, the transmission of undesired sound or vibrations through structural elements, floors, walls or ceilings is a challenging problem. Therefore, surfaces, especially tiled surfaces, are not only expected to be visually appealing and functional, but also to contribute to noise or vibration suppression. This is in particular true for flooring since foot noise is a major source of noise in buildings.

[0005] It is an object of the present invention to provide an underlayment composition having superior self-leveling qualities.

[0006] It is also an object of the present technology to provide an underlayment composition that has superior sound-reduction and vibration-reduction qualities.SUMMARY

[0007] To achieve at least the above-stated objectives, the present technology provides, in a first embodiment, a mortar composition includes a hydraulic binder in an amount of about 15-30 wt. %, and a filler in an amount of about 20-35 wt. %, wherein the filler includes rubber particles having a particle size of 0.5 mm or less. The composition may have a flow rate of at least 200 mm.

[0008] In some embodiments, the hydraulic binder includes Portland cement and calcium aluminate cement. A weight ratio of Portland cement to calcium aluminate cement may be in a range of about 0.01-0.20.

[0009] In certain embodiments of the present technology, the filler is made of rubber particles having a particle size of 0.5 mm or less, and microsphere particles having a particle size of 0.5 mm or less.

[0010] In some embodiments, the composition further includes a dispersible polymer in an amount of about 25 wt. % to about 35 wt. %, a fiber component in an amount of about 1 wt. % to about 10 wt. %, a plasticizer in an amount of about 0.5 wt. % to about 1 wt. %, and / or at least one of a thickener, a retarder, an accelerator, a defoamer, a pH adjusting agent, a shrinkage reduction agent and mixtures thereof.

[0011] The invention also includes a method of making a self-levelling, noise-reducing composition and a method of applying the composition to a substrate, such as floor and the like.

[0012] Other features and advantages of the present invention will become apparent from the following more detailed description, which illustrates, by way of example, the principle of the invention.DETAILED DESCRIPTION

[0013] It is noted that, as used in the specification and the claims, the singular form “a,” “an,” and “the” comprises plural referents unless the context clearly indicates otherwise.For example, reference to a component in the singular is intended to comprise a plurality of components.

[0014] The term “about” is to be construed as modifying a term or value such that it is not an absolute. This term will be defined by the circumstances. This includes, at the veiy least, the degree of expected experimental error, technique error and instrument error for a given technique used to measure a value. In general, this term used in connection with a numerical value throughout the specification and the claims denotes an interval of accuracy, familiar and acceptable to a person skilled in the art. In general, such interval of accuracy is ±10%. Thus, “about ten” means 9 to 11. All numbers in this description indicating amounts, ratios of materials, physical properties of materials, and / or use are to be understood as modified by the word “about,” except as otherwise explicitly indicated.

[0015] The term “comprising” is synonymous with “including,” “having,” “containing,” or “characterized by.” These terms are inclusive and open-ended and do not exclude additional, unrecited elements or method steps.

[0016] The term “essentially free” means here less than 5 wt. %, preferably less than 3 wt. % and in particular less than 1 wt. %, based on the total weight of the composition.

[0017] In accordance with the various embodiments, the composition of the invention includes at least one hydraulic binder. In the context of the present disclosure, the term “hydraulic binder” refers to substances that harden because of hydration chemical reactions producing hydrates. In some embodiments, the hydrates produced are not water-soluble meaning that the hydration chemical reactions of the hydraulic binder take place essentially independently of the water content.

[0018] Examples of suitable hydraulic binders include but are not limited to, Portland cement, alumina cement, ground granulated blast furnace slag cement, gypsum, magnesium phosphate cement, geo-polymer, or any other suitable material. In one or more preferred embodiments, the hydraulic binder is provided in an amount of about 1-40 wt. %, or 5-30 wt. %, or 8-22 wt. %, with respect to the total weight of the composition. In one or more preferred embodiments, the hydraulic binder comprises or consists of cement, such as Portland cement and / or alumina cement.

[0019] Portland cement is a hydraulic cement composed primarily of calcium, silicates, aluminates and iron. The term “alumina cement” refers to a cement with an aluminum content,measured as AI2O3, of at least 30 wt. %, in particular at least 35 wt. %, and more particular 35- 58 wt. %. In some embodiments, calcium aluminate cement may be used, which is composed mainly of calcium aluminates and may be used as the primary binder or in combination with other reactive minerals, such as Portland cement. In some embodiments, the hydraulic binder is a mixture of Portland cement and aluminum cement. Calcium aluminate cement accelerates the initial set from hours to minutes depending on the type and mill of Portland cement used in the combination. The weight ratio of Portland cement to aluminate cement in the composition may be about 0.01 :0.5, and in particular about 0.02:0.2.

[0020] In some preferred embodiments, Portland cement is provided in an amount of about 0.1-10 wt. %, or 0.5-5 wt. %, or 1-2 wt. %, with respect to the total weight of the composition. In one or more preferred embodiments, alumina cement, e.g., calcium aluminate cement, is provided in an amount of about 1-40 wt. %, or about 5-30 wt. %, or about 8-20 wt. %, with respect to the total weight of the composition. In some embodiments, the aluminate cement component may be present in an amount of about 8-10 wt. %. In further embodiments, the aluminate cement component may be present in an amount of about 18-20 wt. %. In additional embodiments, gypsum may also be included in the formulation, such as anhydrite gypsum, in an amount of about 1-20 wt. %, or 5-15 wt. %, with respect to the total weight of the composition.

[0021] In various embodiments, the composition also includes one or more fillers. In one or more embodiments, light weight and / or low-density fillers are used in the formulations to achieve lower density formulation. Suitable fillers may include wood particles, rubber particles, layered particles, plastic particles and / or porous particles, such as recycled rubber, ground silica sand, amorphous silica, silica fume, diatomaceous earth, rice hull ash, blast furnace slag, granulated slag, steel slag, mineral oxides, mineral hydroxides, clays, magnesite or dolomite, metal oxides and hydroxides, polymeric beads or spheres, microspheres, calcium silicate, polystyrene beads, expanded vermiculite, expanded perlite, expanded shale, expanded clay, glass, or mixtures thereof. The amount of the fillers in the formulation may be between about 10 to 70 wt. %, about 20 to 50 wt. %, or about 25-45 wt. %, with respect to the total weight of the composition.

[0022] In one or more preferred embodiments, the filler includes recycled rubber particles. One example of preferred recycled lubber particles is MicroDyne™ 400-BU, which is a free-flowing powder produced from recycled rubber material as defined by ASTM D 5603-01 Grades 3 and 4. The rubber particles may be provided in an amount of about 10-50 wt. %, or 15-40 wt. % or 20-35 wt. %, with respect to the total weight of the composition. In some preferred embodiments, the rubber particles have a particle size that is less than about 600 microns (0.6 mm) or less than about 500 microns (0.5 mm). In additional preferred embodiments, the rubber particles have a particle size in a range of about 500 microns to about 100 microns. Using a rubber filler with a similar particle size in accordance with the present technology is advantageous in that it ensures that the rubber filler particles are not packed as densely and have a larger amount of air pockets between the particles. This results in a better / increased noise and / or vibration suppression characteristics of the compositions.

[0023] In various embodiments, the composition may also include another type of filler, such as microspheres. In some preferred embodiments, the microsphere filler may be a cellular microspheres filler, such as Perlite Sil-Cell 35 / 34 Silicone Coated filler, which is an ultra-light, naturally occurring aluminum silicate microcellular filler that is inert, inorganic, non-toxic and pH neutral. Particles are formed by creating a structure of multicellular spherical bubbles. In some preferred embodiments, the microspheres have a particle size that is less than about 500 microns (0.5 mm) or less than about 300 microns (0.3 mm). The microspheres filler may be provided in an amount of around 1-20 wt. %, or 5-10 wt. %, with respect to the total weight of the composition. In some preferred embodiments, the microspheres filler is provided in an amount of about 7.5 wt. % with respect to the total weight of the composition.

[0024] The inventive compositions may also include one or more fiber materials. Various suitable fibers may be used, including, but not limited to, cellulose fiber, ceramic fiber, glass fiber, mineral wool, steel fiber, and synthetic polymer fibers such as polyamides, polyester, polypropylene, polymethylpentene, polyacrylonitrile, polyacrylamide, viscose, nylon, PVC, PVA, rayon, glass ceramic, carbon, or any mixtures thereof. The fibers are useful to enhance flexural strength and resist surface cracking of the compositions. Fiber materials used in the compositions may be chemically treated, e.g., with hydrophobicity agents, biocides, etc. In one or more preferred embodiments, the fiber material used is wollastonite. The compositions in accordance with various embodiments may contain fibers in an amount of about 0-10 wt. %, or about 2-8 wt. %, or about 5-7 wt. %, based on the total weight of the composition. %

[0025] The compositions may also include dispersing agents, which aid in dispersing and leveling of the compositions once applied to the substrate. Various dispersing agents, suchas re-dispersible polymers, may be used in the compositions. Exemplary re-dispersible polymer powders may include, but are not limited to, vinyl acetate polymer, vinyl acetateethylene copolymer, vinyl acetate-vinyl ester copolymer and / or vinyl acetate-vinyl esterethylene copolymer, with the vinyl ester monomers in each case being vinyl laurate, vinyl pivalate and vinyl versatates, vinyl acetate-acrylic ester copolymer, vinyl acetate-acrylic esterethylene copolymer, styrene-butadiene copolymer and styrene-acrylic ester copolymer, with the acrylic esters in each case being esters with branched or linear alcohols containing from 1 to 10 carbon atoms and in particular styrene acrylate copolymer, polyvinyl acetate, styrene butadiene copolymer or mixtures of two or more thereof. Dispersible agents may be present in the compositions in amounts of about 10 wt. % to about 50 wt. %, or from about 20 wt. % to about 40 wt. %, or from about 25 wt. % to about 35 wt. %, based on the total weight of the composition.

[0026] The various embodiments of the present compositions may also include various other modifiers in amounts ranging from about 0 wt. % to about 20 wt. %, based on the total weight of the composition. These modifiers may include, for example, defoamers, surfactants, biocides, preservatives, retardants / setting time regulators, rheological modifiers, dispersing agents, viscosity modifiers / thickeners, pigments, colorants, and combinations thereof.

[0027] Defoamers may be present in the composition in an amount of about 0 wt. % to about 1 wt. %, or from about 0 wt. % to about 0.5 wt. %, based on the total weight of the composition. Exemplary defoamers may include, but are not limited to, polyether chemistries, fatty acids, modified siloxanes, and combinations thereof. In one or more advantageous embodiments, a defoamer comprising a blend of liquid hydrocarbons and polyglycols on an inorganic carrier may be used, which is particularly useful for application in dry blends which are dissolved in water before application. The addition of defoamers results in low foaming solutions, specifically aqueous pastes or masses with very low air content.

[0028] Modifiers may also include surfactants to decrease water surface tension, reduce viscosity, eliminate entrained air, and / or stabilize the compositions. In one or more embodiments the surfactants may include plasticizers, such as polymeric compounds that have anionic and / or anionogenic groups and polyether side chains, which may comprise polyalkylene glycol side chains. The anionic and / or anionogenic groups and the polyether side chains may be attached to the backbone of the polymeric dispersant. Exemplary plasticizers include, but are not limited to, a polycarboxylate ether, a phosphorylated polycondensationproduct or a sulfonic acid and / or sulfonate group containing dispersant and the like, and mixtures thereof. In one preferred embodiment, the plasticizer comprises a polycarboxylate ether. Plasticizers may be present in amounts ranging from about 0 wt. % to about 2 wt. %, or about 0.5 wt. % to about 1 wt. %, based on the total weight of the composition. In some embodiments, pH adjusting agents may be added to make the compositions alkaline to ensure that the plasticizer can work effectively and also to increase the pot life. Any suitable pH adjusting agent, such as soda ash, may be used, in an amount of about 0 wt. % to about 0.5 wt. %, or about 0 wt. % to about 0.2 wt. %, based on the total weight of the composition.

[0029] In additional embodiments, the compositions may also contain one or more thickening agents or rheology modifiers. Thickening agents act to increase viscosity in cementbased and calcium sulphate-based materials to prevent bleeding and segregation. Various thickening / thixotropic agents may be used, including, but not limited to, diutan gum, high molecular weight water soluble polymers and the like. The compositions may include about 0.03 wt. % to about 0.07 wt. % of thickeners based on the total weight of the composition.

[0030] The compositions may also include one or more retarder compounds. Retarder functions to slow down the reaction and to allow longer working time before the composition sets. Exemplary retarders may include, but are not limited to, organic hydroxycarboxylic acids, organic acids or polyacids and salts or inorganic soluble salts of metals, e.g., magnesium, aluminium, manganese, nickel, copper, zinc, tin or lead. In some preferred embodiments, the retarder may be a dihydroxysuccinic acid. Retarder compounds may be provided in an amount of about 0 wt. % to about 0.05 wt. %, based on the total weight of the composition.

[0031] In one or more embodiments, the composition may also contain accelerator(s). Accelerators may be added to adjust / speed up setting and hardening time of the self-leveling compositions to reduce construction time. Accelerators may include calcium-silicate-hydrate, calcium formate, calcium nitrate, calcium chloride, calcium hydroxide, lithium carbonate and lithium sulfate. In one or more preferred embodiments, lithium-based accelerators may be used, such as lithium sulfate monohydrate or lithium carbonate-based agents. Lithium based accelerators are particularly suitable for self-leveling compositions containing calcium aluminate hydraulic binders. The compositions may contain between about 0 wt. % to about 0. 1 wt. % of accelerator compound(s), based on the total weight of the composition.

[0032] Shrinkage reduction agents may also be included in the compositions of the present invention. Shrinkage reduction agents reduce the shrinkage in cementitious systems, whichin turn prevents cracking of the hardened composition over time. Various suitable shrinkage reduction agents may be used in accordance with the present technology. In some preferred embodiments, a shrinkage reduction agent comprises a mixture of aliphatic alcohols and glycols with an inorganic carrier. The compositions may contain from about 0.5 wt. % to about 10 wt. %, or from about 1 wt. % to about 5 wt. % of shrinkage reduction agent(s), based on the total weight of the composition.

[0033] Biocides may be present in the compositions in amounts of about 0 wt. % to about 1 wt. %. Biocides may include, but are not limited to, conventional powder and liquid based biocides, or combinations thereof. The preservatives may also include conventional organic and / or inorganic preservatives in amounts of about 0 wt. % to about 0.5 wt. %, based on the total weight of the composition.

[0034] In certain embodiments of the invention, other modifiers may include inorganic pigments, inorganic fillers, water repellants, and combinations thereof. The inorganic pigments may be present in amounts of about 0 wt. % to about 4 wt. %, based on the total weight of the composition. Exemplary inorganic pigments may include, but are not limited to, iron oxides, titanium dioxides, chrome oxides, and combinations thereof. Inorganic fillers may be present in amounts of about 0 wt. % to about 10 wt. % based on the total weight of the composition, with such exemplary fillers including limestone. The compositions may also include water repellants, such as lignosulphonates and / or polycarboxylates. The water repellants may be present in amounts of about 0 wt. % to about 2 wt. %, based on the total weight of the composition.

[0035] The present technology includes a method of applying a self-leveling mix to a substrate, such as a floor, a wall surface, and such. The self-levelling mixes of the present technology are best suited for laying at a thickness of about 5-25 mm, or about 10-15 mm, but can be used to a depth or variation in depth of up to 25 mm. In some embodiments, an additional primer layer may be applied between the substrate and the first layer. One suitable primer may be a latex composition based on polyvinyl acetate homopolymer or copolymer, another may be a styrene butadiene rubber.

[0036] In use, the self-leveling mix in a dry form is combined with water to a smooth pasty consistency, and then more water is added to produce a highly fluid material. This is then applied to the floor to an approximately even thickness. The waterxement mix ratio may be about 0.3 to 1 : 1 , or about 0.4 to 0.55: 1. The compositions have a sufficient flow rate as described below to allow for easy application to the substrate as a self-leveling mortar. Thecompositions achieve superior noise reduction characteristics as shown and discussed in more detail below.

[0037] Further advantageous configurations of the invention are evident from the exemplary embodiments.

[0038] EXAMPLE 1

[0039] An exemplary composition in accordance with the present technology is described below. The composition may be made by mixing together the following components in dry form. The resulting composition is in a form of a dry powder:1Particle size of 0.5 mm or less.2Particle size of 0.3 mm or less.3Thickeners, retardants, accelerators, pH adjusting agents, shrinkage reducing agents, defoamers, foaming agents, other fillers, superabsorbent, etc.|0040] EXAMPLE 2

[0041] Another exemplary composition in accordance with the present technology was made by mixing together the following components in dry form to obtain a dry powder mix:1Portland Cement High Alkali, Type III or the like2Ciment Fondu® available from Kerneos Inc. or the like3Snow White® Anhydrous Calcium Sulfate Filler or the like4MicroDyne® 400-BU, particle size 0.5 mm or less or the like5Perlite Sil-Cell® 35 / 34 Silicone Coated, particle size 0.3 mm or less or the like6Vinyl acetate and ethylene copolymer (VINNAPAS® 5115 L) or the like7Wollastonite (NY AD G®) or the like8PolyCarboxy ate Ether (PCE) polymer (Peramin® CONPAC or Metflux® 6681F) or the like9Lithium sulfate monohydrate accelerator (Peramin® AXL 80) or the like10Blend of aliphatic alcohols and glycols with an inorganic carrier (Metolat® P 872) or the like11Soda ash or the like12Diutan gum (Kelco-Crete® DG-F), high molecular weight water soluble polymers (Stands® 3040F) and the like13Retarders, defoamers, other fillers (limestone) and the like

[0042] The dry components in the compositions are mixed with water to obtain processable compositions.

[0043] Sound dampening tests were performed on the inventive compositions in Example 2 in accordance with ASTM E2179, ASTM E989, and ASTM E 492. In particular, a smaller version of a sound chamber based on ASTM E2179 was used with a standard hammer (Norsonic) and a sound recorder to record sound levels (dB) at different frequencies in one- third octave, as per ASTM E989 and ASTM E 492 to obtain Delta IIC values. The tests showed that the inventive compositions achieve values of 10 or above. In some embodiments, the compositions may have Delta IIC values of 18 or above. In additional embodiments, the compositions achieve the Delta IIC values of least 20.

[0044] The compositions in Example 2 were also tested for compressive and flexural strength using ASTM standards Cl 09 and C348, respectively. Measurements after 28 days following application show the compressive strength of about 600 (SD: 72) psi and the flexural strength of about 177 (SD: 16) psi, which show that the compositions have satisfactory' strength and other physical characteristics for mortar compositions.

[0045] Flow rate testing was performed on the compositions in Example 2 according to the flow test process comparable to ASTM Cl 708. Tubes with a 2-inch diameter and 4-inch height were used for the testing. The measured flow rate of the 2 by 4 inch cylinder cup directly after preparation was around 200 mm, which shows that the compositions exhibit satisfactory flow behavior needed for easy processing.

[0046] The compositions in Example 2 were further tested for gel time using an internal test method that gives reactivity as described in ASTM Cl 897. The gel time of the compositions in Example 2 was around 4-6 hours.

[0047] Although the technology has been described and illustrated with respect to exemplary7embodiments thereof, it should be understood by those skilled in the art that the foregoing and various other changes, omissions and additions may be made therein and thereto, without parting from the spirit and scope of the present technology. It should also be understood that features described and illustrated in reference to one embodiment may be employed in other embodiments as appropriate.

[0048] It should be noted that the invention in its broader aspects is not limited to the specific details, representative compositions, methods, and processes, and illustrative examples described in connection with the preferred embodiments and preferred methods. Modifications and equivalents will be apparent to practitioners skilled in this art and are encompassed within the spirit and scope of the appended claims.

Claims

VARIOUS EMBODIMENTS1. A floor underlayment composition, comprising: a hydraulic binder in an amount of about 15-30 wt. %, a filler in an amount of about 20-35 wt. %, wherein the filler comprises rubber particles having a particle size of 0.5 mm or less, wherein the composition has a flow rate of at least 200 mm.

2. The composition of claim 1 , wherein the hydraulic binder comprises Portland cement and calcium aluminate cement, and wherein a weight ratio of Portland cement to calcium aluminate cement is in a range of about 0.01-0.2.

3. The composition of claim 1, wherein the filler consists essentially of the rubber particles having the particle size of 0.5 mm or less, and microsphere particles having a particle size of 0.5 mm or less.

4. The composition of claim 1, further comprising a dispersible polymer in an amount of about 25 wt. % to about 35 wt. %.

5. The composition of claim 1, further comprising a fiber component in an amount of about 1 wt. % to about 10 wt. %.

6. The composition of claim 1, further comprising a plasticizer in an amount of about 0.5 wt. % to about 1 wt. %.

7. The composition of claim 1, further comprising at least one of a thickener, a retarder, an accelerator, a defoamer, a pH adjusting agent, a shrinkage reduction agent and mixtures thereof.

8. A method of leveling a surface of a floor, comprising: mixing the floor underlayment composition of claim 1 with water to obtain a ready - to-use mix, wherein the weight ratio of water to total weight of the floor underlayment composition is in a range of about 0.4-0.55:1; and applying the ready-to-use mix to the floor surface.

9. A method of using the floor underlayer composition according to claim 1, comprising: mixing the floor underlayment composition with water in a weight ratio of about1:0 3-1 , and performing acoustic damping, noise reduction and / or vibration reduction on a substrate with the floor underlayment composition.