Compositions and uses thereof

Abstract

The present disclosure relates to compositions comprising magnesium oxide (MgO) and magnesium chloride (MgCl2), particularly compositions comprising MgO, MgCl2 and an organic solvent-based resin, which may, for example, be suitable for use in the preparation of cementitious articles. The present disclosure also relates to cementitious articles formed from the compositions, and methods of forming the same.

Description

COMPOSITIONS AND USES THEREOFCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from Australian Provisional Patent Application No. 2024902180 filed 15 July 2024, the entire contents of which are incorporated herein by cross-reference.TECHNICAL FIELD

[0002] The present disclosure relates generally to compositions comprising magnesium oxide (MgO) and magnesium chloride (MgCE). In particular, the present disclosure relates to compositions comprising MgO, MgCh, and an organic solvent-based resin, which may, for example, be suitable for use in the preparation of cementitious articles.BACKGROUND

[0003] Some cementitious or cementitious-like articles comprise crystalline silica (SiO2). Engineered stone, a non-porous composite material comprising crystalline silica, is often used in kitchen benchtop applications. Cutting and / or otherwise processing engineered stone, and other cementitious or cementitious-like articles that include crystalline silica, releases crystalline silica dust particles. Personnel exposed to crystalline silica dust particles are at risk of contracting silicosis, also known as grinder's disease and Potter's rot. Silicosis is a type of pneumoconiosis having no cure, wherein the inhalation of dust (i.e., crystalline silica dust particles) causes scarring of the lungs (interstitial fibrosis). Symptoms of silicosis include shortness of breath, coughing, and fatigue, among others. Treatment options focus on symptom relief rather than reversing damage associated with the disease.

[0004] In response to the risk of silicosis, Australia has imposed a ban on engineered stone. In the United States, the Occupational Health and Safety Administration has required that certain safety measures are met for employees that may be exposed to silica dust. Other jurisdictions are revisiting health and safety requirements concerning the handling of articles that are capable of generating crystalline silica dust. As such, there is a need to provide improved or alternative compositions for forming cementitious articles (e.g., benchtops) that are free of silica (e.g., crystalline silica dust).SUMMARY

[0005] In one aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh).

[0006] In some embodiments, the MgO and the MgCh are present at a molar ratio of from about 6: 1 to about 8: 1, from about 6.5: 1 to about 7.5: 1, or about 7: 1 (MgO : MgCh).

[0007] In some embodiments, the MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition.

[0008] In some embodiments, the MgCh is present in an aqueous solution. In some embodiments, the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. In some embodiments, water (H2O) and the MgCh are present in the aqueous solution at a molar ratio of from about 10: 1 to about 15: 1, from about 11 : 1 to about 14: 1, from about 11 : 1 to about 13: 1, or about 12: 1 (H2O : MgCh).

[0009] In some embodiments, the organic solvent-based resin is free of a siloxane moiety. In some embodiments, the organic solvent-based resin is selected from the group consisting of an epoxy resin, a polyester resin, a phenolic resin, an alkyd resin, an acrylic resin, a vinyl resin, a polyacetal resin, a polyurethane resin, an amino resin, an aldehyde resin, a maleic resin, a ketonic resin, a polyamide resin, a cellulose resin, and any combination thereof. In some embodiments, the organic solvent-based resin is selected from the group consisting of an epoxy resin, a polyester resin, an acrylic resin, and any combination thereof.

[0010] In some embodiments, the composition further comprises at least one of an organic solvent, a dye, a catalyst, and a hardener. In some embodiments, the organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition.

[0011] In some embodiments, the composition further comprises a filler. In some embodiments, the filler is selected from the group consisting of cellulose or a derivative thereof, glass, sawdust, wood chips, and any combination thereof. In some embodiments, the filler is present in an amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 7.5 wt.%, or from about 1 wt.% to about 5 wt.% based on the total weight of the composition.

[0012] In some embodiments, the composition further comprises phosphoric acid. In some embodiments, the phosphoric acid is about 85 wt.% phosphoric acid in water (H2O). In some embodiments, the phosphoric acid is present in an amount of from about 0.01 wt.% to about 5 wt.%, from about 0.1 wt.% to about 1.0 wt.%, or from about 0.1 wt.% to about 0.5 wt.% based on the total weight of the composition.

[0013] In some embodiments, the composition further comprises a decorative additive. In some embodiments, the decorative additive is selected from the group consisting of an epoxy flake, a recycled plastic, and any combination thereof. In some embodiments, the decorative additive is present in amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 5 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition.

[0014] In some embodiments, the composition further comprises a hydrophobic additive. In some embodiments, the hydrophobic additive is a silicone-based hydrophobic additive. In some embodiments, the hydrophobic additive is present in an amount of from about 0.1 wt.% to about 4 wt.%, from about 1 wt.% to about 3 wt.%, or from about 1 wt.% to about 2 wt.% based on the total weight of the composition.

[0015] In some embodiments, the composition further comprises a superplasticizer. In some embodiments, the superplasticizer is present in an amount of from about 0.1 wt.% to about 5 wt.%, from about 1 wt.% to about 4 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition.

[0016] In some embodiments, the composition further comprises a defoamer. In some embodiments, the defoamer is a silicone-based defoamer. In some embodiments, the defoamer is present in an amount of from about 0.1 wt.% to about 4 wt.%, from about0.5 wt.% to about 2.5 wt.%, or from about 1 wt.% to about 2 wt.% based on the total weight of the composition.

[0017] In some embodiments, the composition comprises 5 wt.% or less of any silicone- based additives. In some embodiments, the composition is substantially free of silica (SiCh) (e.g., crystalline silica). In some embodiments, the composition is free of a water-based resin.

[0018] In another aspect, the present disclosure provides a cementitious formed from a composition described herein. In some embodiments, the cementitious article is a benchtop, a tile, a panel, a frame, a truss, a nog, a load-bearing member, a stud, a lintel, or a ledger. In some embodiments, the cementitious article is a benchtop.

[0019] In some embodiments, a sealant is disposed on an exterior surface of the cementitious article. In some embodiments, the cementitious article has a flexural strength of from about 4 MPa to about 20 MPa. In some embodiments, the cementitious article has a Young's modulus of from about 1,000 MPa to about 4,000 MPa. In some embodiments, the cementitious article has a water absorption of less than about 10%, less than about 7.5%, less than about 5%, or less than about 2.5% after submersion in water for 28 days.

[0020] In another aspect, the present disclosure provides a method of forming a cementitious article. The method comprises: a) mixing magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin to form a cementitious mixture, wherein the MgO and the MgCh are present in the cementitious mixture at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh); b) disposing the cementitious mixture in a mould; and c) allowing the cementitious mixture to cure in the mould, thereby forming the cementitious article.

[0021] In some embodiments, mixing step a) further comprises mixing the MgO, the MgCh, the organic solvent-based resin, and at least one of a filler, a phosphoric acid, a hydrophobic additive, a decorative additive, a superplasticizer, and a defoamer.

[0022] In some embodiments, mixing step a) further comprises: a-1) mixing the MgO and the MgCh to form a pre-cementitious mixture;a-2) mixing an organic solvent-based resin and at least one of an organic solvent, a dye, a catalyst, and a hardener to form an organic solvent-based resin mixture; and a-3) mixing the pre-cementitious mixture and the organic solvent-based resin mixture to form the cementitious mixture.

[0023] In some embodiments, mixing step a) further comprises: a-1) mixing the MgO, the MgCh, and at least one of a filler, a phosphoric acid, a hydrophobic additive, a decorative additive, a superplasticizer, and a defoamer to form a pre-cementitious mixture; a-2) mixing an organic solvent-based resin and at least one of an organic solvent, a dye, a catalyst, and a hardener to form an organic solvent-based resin mixture; and a-3) mixing the pre-cementitious mixture and the organic solvent-based resin mixture to form the cementitious mixture.

[0024] In some embodiments, the method further comprises: d) agitating the cementitious mixture prior to step c).

[0025] In some embodiments, the method further comprises: e) cutting and / or polishing the cementitious article after step c).

[0026] In some embodiments, the method further comprises: f) disposing a sealant on an exterior surface of the cementitious article after step c).BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Embodiments of the present disclosure will now be described with reference to the following Figures, which are intended to be exemplary only, and in which:

[0028] Figure 1 is a graphical representation of water absorption (y-axis; %) for cementitious articles according to Example 1 at various time points (x-axis; days) after submersion in water, wherein the cementitious articles are formed from compositions comprising magnesium oxide (MgO), magnesium chloride (MgCh), and a water-based resin (Samples 1-5), a composition comprising MgO and MgCh and free of a resin (Sample 6), and a composition comprising MgO, MgCh, and an organic solvent-based resin.

[0029] Figure 2 is a graphical representation of water absorption (y-axis; %) for a cementitious article according to Example 2 at various time points (x-axis; days) after submersion in water, wherein the cementitious article is formed from a composition comprising MgO, MgCh, and an organic solvent-based resin.

[0030] Figure 3 is a graphical representation of water penetration distance (y-axis; mm) for a cementitious article according to Example 2 at various time points (x-axis; days) after submersion in water, wherein the cementitious article is formed from a composition comprising MgO, MgCh, and an organic solvent-based resin.

[0031] Figure 4 is a graphical representation of flexural strength (left y-axis; MPa) and water absorption (right y-axis; %) for a cementitious article according to Example 2 at various time points (x-axis; days) after submersion in water, wherein the cementitious article is formed from a composition comprising MgO, MgCh, and an organic solvent-based resin.

[0032] Figures 5A-5F is a graphical representation of flexural strength (left y-axis; MPa) and flexural strain (x-axis; %) for a cementitious article according to Example 2 at 0 days (Figure 5A), 1 day (Figure 5B), 7 days (Figure 5C), 14 days (Figure 5D), 21 days (Figure 5E), and 28 days (Figure 5F) after submersion in water, wherein the cementitious article is formed from a composition comprising MgO, MgCh, and an organic solvent-based resin.

[0033] Figure 6 is a graphical representation of Young's modulus of elasticity (left y-axis; MPa) and water absorption (right y-axis; %) for a cementitious article according to Example 2 at various time points (x-axis; days) after submersion in water, wherein the cementitious article is formed from a composition comprising MgO, MgCh, and an organic solvent-based resin.

[0034] Figure 7 is a graphical representation of water absorption (y-axis; %) for cementitious articles according to Example 3 at various time points (x-axis; days) after submersion in water, wherein the cementitious articles are formed from compositions comprising magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solventbased resin (Samples 14-17).

[0035] Figure 8 is a graphical representation of water absorption (y-axis; %) for cementitious articles according to Example 4 at various time points (x-axis; days) aftersubmersion in water, wherein the cementitious articles are formed from compositions comprising magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solventbased resin (Samples 18-21).

[0036] Figure 9 is a bar graph of compressive strength (left y-axis; MPa) and EhO / MgCh molar ratio (x-axis) for cementitious articles according to Example 5, wherein the cementitious articles are formed from a composition comprising MgO, MgCh, sawdust, perlite and fly ash.

[0037] Figure 10 is a bar graph of Young's modulus (left y-axis; MPa) and EhO / MgCh molar ratio (x-axis) for cementitious articles according to Example 5, wherein the cementitious articles are formed from a composition comprising MgO, MgCh, sawdust, perlite and fly ash.GENERAL DEFINITIONS

[0038] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0039] Unless otherwise specified, the indefinite articles “a”, “an” and “the” as used herein, include plural aspects. Thus, for example, reference to “an agent” includes a single agent, as well as two or more agents; reference to “the composition” or “formulation” includes a single composition or formulation, as well as two or more compositions or formulations; and so forth.

[0040] As used herein, the term “about”, as applied to one or more reference values, refers to a value that is similar or approximate to a stated reference value. In certain embodiments, the term “about” refers to a range of values that fall within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less in either direction (greater than or less than) of the stated reference value unless otherwise stated or otherwise evident from the context (except where such number would exceed 100% of a possible value). In a particular embodiment, the term “about” means ±10% of the recited value.

[0041] Throughout this specification and the claims that follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising”, willbe understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

[0042] The term “consisting of’ means “consisting only of’, that is, including and limited to the integer or step or group of integers or steps, and excluding any other integer or step or group of integers or steps.

[0043] The term “consisting essentially of’ means the inclusion of the stated integer or step or group of integers or steps, but other integer or step or group of integers or steps that do not materially alter or contribute to the working of the invention may also be included.

[0044] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that that prior art forms part of the common general knowledge.

[0045] Other definitions may be found throughout the description.DETAILED DESCRIPTION

[0046] The present disclosure broadly relates to compositions for forming cementitious articles. In particular, the present inventors have found that compositions comprising magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin may be used to form cementitious articles, such as benchtops, which may be substantially free of silica.

[0047] The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). In some embodiments, the MgO and the MgCh are present at a molar ratio of from about 6: 1 to about 8: 1, from about 6.5: 1 to about 7.5: 1, or about 7: 1 (MgO : MgCh). In some embodiments, the MgO and the MgCh are present at a molar ratio of from about 6: 1 to about 8: 1 (MgO : MgCh). In some embodiments, the MgO and the MgCh are present at a molar ratio of from about 6.5: 1 to about 7.5: 1 (MgO : MgCh). In some embodiments, the MgO and the MgCh are present at a molar ratio of from about 6.25: 1 to about 7.25: 1 (MgO : MgCh). For example, the ratio of MgO : MgCh may be about 5: 1, about 6: 1, about 7: 1, about 8: 1, or about 9: 1. In some embodiments, the MgO and the MgCh are present at a molar ratio of about 7: 1 (MgO : MgCh).

[0048] In some embodiments, the MgO is present in an amount of from about 20 wt.% toabout 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. In some embodiments, the MgO is present in an amount of from about 20 wt.% to about 60 wt.% based on the total weight of the composition. In some embodiments, the MgO is present in an amount of from about 25 wt.% to about 55 wt.% based on the total weight of the composition. In some embodiments, the MgO is present in an amount of from about 30 wt.% to about 50 wt.% based on the total weight of the composition. In some embodiments, the MgO is present in an amount of from about 35 wt.% to about 45 wt.% based on the total weight of the composition. For example, the MgO may be present in an amount of about 20 wt.%, about 30 wt.%, about 35 wt.%, about 40 wt.%, about 45 wt.%, about 50 wt.%, about 55 wt.%, or about 60 wt.%, based on the total weight of the composition.

[0049] In some embodiments, the MgCh is present in an aqueous solution. The aqueous solution may, for example, comprise, consist essentially of, or consist of the MgCh and water (H2O). In some embodiments, the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. In some embodiments, the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.% based on the total weight of the composition. In some embodiments, the aqueous solution of MgCh is present in an amount of from about 25 wt.% to about 55 wt.% based on the total weight of the composition. In some embodiments, the aqueous solution of MgCh is present in an amount of from about 30 wt.% to about 50 wt.% based on the total weight of the composition. In some embodiments, the aqueous solution of MgCh is present in an amount of from about 35 wt.% to about 45 wt.% based on the total weight of the composition. For example, the aqueous solution of MgCh may be present in an amount of about 20 wt.%, about 30 wt.%, about 35 wt.%, about 40 wt.%, about 45 wt.%, about 50 wt.%, about 55 wt.%, or about 60 wt.%, based on the total weight of the composition.

[0050] When the MgCh is present in an aqueous solution, water (H2O) and the MgCh may be present in the aqueous solution at a molar ratio of from about 10: 1 to about 15: 1, from about 11 : 1 to about 14: 1, from about 11 : 1 to about 13: 1, or about 12: 1 (H2O : MgCh). In some embodiments, H2O and the MgCh are present in the aqueous solution at a molar ratio of from about 10: 1 to about 15: 1 (H2O : MgCh). In some embodiments, H2O and the MgChare present in the aqueous solution at a molar ratio of from about 11 : 1 to about 14: 1 (H2O : MgCh). In some embodiments, H2O and the MgCh are present in the aqueous solution at a molar ratio of from about 11 : 1 to about 13: 1 (H2O : MgCh). For example, H2O and the MgCh may be present in the aqueous solution at a molar ratio of from about 10: 1, about 11 : 1, about 12: 1, about 13: 1, about 14: 1, or about 15: 1 (H2O : MgCh). In some embodiments, H2O and the MgCh are present in the aqueous solution at a molar ratio of about 12: 1 (H2O : MgCh).

[0051] Compositions comprising MgO and MgCh generate magnesium oxychloride (MOC), which exhibits beneficial mechanical properties (e.g., flexural strength and Young's modulus). In particular, these compositions give rise to, inter alia, crystalline phase 5 MOC via a hydration process represented in Equation [1]:5MgO + MgCh + 13H2O 5Mg(OH)2MgCh 8H2O (“phase 5 MOC”)[1]

[0052] Phase 5 MOC exhibits a compactness and stiffness suitable for a range of cementitious articles. However, phase 5 MOC is susceptible to degradation when exposed to excess water. Degradation of phase 5 MOC weakens underlying mechanical properties of cementitious articles, and may ultimately result in failure of the cementitious article. The phase 5 MOC degradation pathway is represented in Equation [2]:5Mg(OH)2-MgCh-8H2O+xH2O 6Mg(OH)2+ MgCh-(8+x)H2O[2]

[0053] Certain cementitious articles, such as benchtops, are frequently exposed to water. The present inventors have surprisingly found that the inclusion of an organic solvent-based resin in cementitious compositions comprising MgO and MgCh may provide cementitious articles that retain sufficient mechanical properties upon exposure to water.

[0054] The terms “organic solvent-based resin” and “oil-based resin” may be used interchangeably herein to refer to resins wherein an organic solvent is a carrying medium. Such resins may be substantially free (i.e., comprise less than about 1 wt.%, or less than about 0.1 wt.%) of water. In some embodiments, the organic solvent-based resin is free of water. In contrast to an organic solvent-based resin, the term “water-based resin” refers to a resin wherein water is a substantial component of the carrying medium (i.e., at least about1 wt.%, at least about 2.5 wt.%, at least about 5 wt.%, at least about 10 wt.%, at least about 20 wt.%, at least about 30 wt.%, at least about 40 wt.%, or at least about 50 wt.% of the carrying medium based on the total weight of the carrying medium).

[0055] In some embodiments, the organic solvent-based resin is free of a siloxane moiety (i.e., a Si-O-Si moiety). In some embodiments, the organic solvent-based resin is selected from the group consisting of an epoxy resin, a polyester resin, a phenolic resin, an alkyd resin, an acrylic resin, a vinyl resin, a polyacetal resin, a polyurethane resin, an amino resin, an aldehyde resin, a maleic resin, a ketonic resin, a polyamide resin, a cellulose resin, and any combination thereof. In some embodiments, the organic solvent-based resin is an epoxy resin. In some embodiments, the organic solvent-based resin is a polyester resin. In some embodiments, the organic solvent-based resin is a phenolic resin. In some embodiments, the organic solvent-based resin is an alkyd resin. In some embodiments, the organic solventbased resin is an acrylic resin. In some embodiments, the organic solvent-based resin is a vinyl resin. In some embodiments, the organic solvent-based resin is a polyacetal resin. In some embodiments, the organic solvent-based resin is a polyurethane resin. In some embodiments, the organic solvent-based resin is an amino resin. In some embodiments, the organic solvent-based resin is an aldehyde resin. In some embodiments, the organic solventbased resin is a maleic resin. In some embodiments, the organic solvent-based resin is a ketonic resin. In some embodiments, the organic solvent-based resin is a polyamide resin. In some embodiments, the organic solvent-based resin is a cellulose resin. In some embodiments, the organic solvent-based resin is selected from the group consisting of an epoxy resin, a polyester resin, an acrylic resin, and any combination thereof. In some embodiments, the organic solvent-based resin is a laminating resin.

[0056] In some embodiments, the organic solvent-based resin is present in an amount of from about 1 wt.% to about 15 wt.%, from about 2.5 wt.% to about 12.5 wt.%, or from about 5 wt.% to about 10 wt.% based on the total weight of the composition. In some embodiments, the organic solvent-based resin is present in an amount of from about 1 wt.% to about 15 wt.% based on the total weight of the composition. In some embodiments, the organic solvent-based resin is present in an amount of from about 2.5 wt.% to about 12.5 wt.% based on the total weight of the composition. In some embodiments, the organic solvent-based resin is present in an amount of from about 5 wt.% to about 10 wt.% based on the totalweight of the composition. For example, the organic solvent-based resin may be present in an amount of about 1 wt.%, about 2.5 wt.%, about 5 wt.%, about 7.5 wt.%, about 10 wt.%, about 12.5 wt.%, or about 15 wt.%, based on the total weight of the composition.

[0057] In some embodiments, the composition further comprises at least one of an organic solvent, a dye, a catalyst, and a hardener. The organic solvent is not particularly limited, and may be any solvent suitable for use as a carrying medium for the organic solvent-based resin. For example, the organic solvent may be, by way of non-limiting example, a hydrocarbon solvent (e.g., pentane, hexane, heptane, octane, decane, hexadecane, cyclohexane, etc.), an aromatic hydrocarbon solvent (e.g., benzene, toluene, xylene, etc.), a ketone solvent (e.g., acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), cyclohexanone (CHK), isophorone, etc.), an ester solvent (methyl acetate, ethyl acetate, / / -butyl acetate, isobutyl acetate, etc.), an ether solvent (e.g., ethylene glycol butyl ether, diethylene glycol monoethyl ether, etc.), an alcohol solvent (e.g., ethanol, isopropanol, / / -butanol, etc.), or any combination thereof.

[0058] Suitable dyes, catalysts, and hardeners would be known to persons skilled in the art in relation to the applicable organic solvent-based resin. For example, when the organic solvent-based resin is a polyester resin, the catalyst may be methyl ethyl ketone peroxide (MEKP). The term “hardener”, “curing agent”, and “cross-linker” are used interchangeably herein to refer to an agent that, during curing, reacts with the organic solvent-based resin to form a cured polymer. For example, the hardener may be, by way of non-limiting example, an amine (e.g., aliphatic amines, cycloaliphatic amines, aromatic amines, etc.), a poylamide, a polymercaptan, an anhydride, a phenol, or any combination thereof.

[0059] In some embodiments, the organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition. In some embodiments, the organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.% based on the total weight of the composition. In some embodiments, the organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 7.5 wt.% to about 20 wt.%based on the total weight of the composition. In some embodiments, the organic solventbased resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 10 wt.% to about 15 wt.% based on the total weight of the composition. For example, the organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener may be present in a combined amount of about 5 wt.%, about 7.5 wt.%, about 10 wt.%, about 12.5 wt.%, about 15 wt.%, about 17.5 wt.%, about 20 wt.%, about 22.5 wt.%, or about 25 wt.%, based on the total weight of the composition

[0060] In some embodiments, the polymer formed from the organic solvent-based resin and the at least one of the catalyst and the hardener is free of a siloxane moiety (i.e., a Si-O-Si moiety).

[0061] In some embodiments, the composition further comprises a filler. Suitable fillers would be known to persons skilled in the art in relation to the cementitious article to be formed. In some embodiments, the filler is selected from the group consisting of cellulose or a derivative thereof, glass, sawdust, wood chips, and any combination thereof. In some embodiments, the filler is cellulose or a derivative thereof (e.g., methyl cellulose, nitrocellulose, hydroxypropyl cellulose, carboxymethylcellulose (CMC), sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose (HPMC), or hydroxyethyl cellulose (HEC), etc.). In some embodiments, the filler is glass (e.g., crushed glass, recycled glass, crushed recycled glass, etc.). In some embodiments, the filler is sawdust. In some embodiments, the filler is wood chips. The filler may also be a decorative additive as described herein (e.g., a recycled plastic, such as recycled HDPE).

[0062] In some embodiments, the filler is present in an amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 7.5 wt.%, or from about 1 wt.% to about 5 wt.% based on the total weight of the composition. In some embodiments, the filler is present in an amount of from about 0.1 wt.% to about 10 wt.% based on the total weight of the composition. In some embodiments, the filler is present in an amount of from about 1 wt.% to about 7.5 wt.% based on the total weight of the composition. In some embodiments, the filler is present in an amount of from about 1 wt.% to about 5 wt.% based on the total weight of the composition. For example, the filler may be present in an amount of about 0.1 wt.%,about 0.5 wt.%, about 1 wt.%, about 2.5 wt.%, about 5 wt.%, about 7.5 wt.%, or about 10 wt.%, based on the total weight of the composition.

[0063] In other embodiments, the composition comprises a silica-based filler. In some embodiments, the silica-based additive is crystalline silica, perlite, fly ash, and any combination thereof. In some embodiments, the filler is perlite. In some embodiments, the filler is fly ash (e.g., Class C, Class F fly ash, etc.). In some embodiments, the silica-based filler is present in an amount of from about 0.1 wt.% to about 30 wt.%, from about 1 wt.% to about 25 wt.%, from about 1 wt.% to about 20 wt.%, from about 5 wt.% to about 10 wt.%, or from about 5 wt.% to about 20 wt.%, based on the total weight of the composition. For example, the silica-based filler may be present in an amount of about 0.1 wt.%, about 0.5 wt.%, about 1 wt.%, about 2.5 wt.%, about 5 wt.%, about 7.5 wt.%, about 10 wt.%, about 12.5 wt.%, about 15 wt.%, about 17.5 wt.%, about 20 wt.%, about 25 wt.%, or about 30 wt.%, based on the total weight of the composition.

[0064] In some embodiments, the composition comprises phosphoric acid. In some embodiments, the phosphoric acid is 85 wt.% phosphoric acid in water (H2O). In some embodiments, the phosphoric acid is present in an amount of from about 0.01 wt.% to about 5 wt.%, from about 0.1 wt.% to about 1.0 wt.%, or from about 0.1 wt.% to about 0.5 wt.% based on the total weight of the composition. In some embodiments, the phosphoric acid is present in an amount of from about 0.01 wt.% to about 5 wt.% based on the total weight of the composition. In some embodiments, the phosphoric acid is present in an amount of from about 0.1 wt.% to about 1.0 wt.% based on the total weight of the composition. In some embodiments, the phosphoric acid is present in an amount of from about 0.1 wt.% to about 0.5 wt.% based on the total weight of the composition. For example, the phosphoric acid may be present in an amount of about 0.01 wt.%, about 0.05 wt.%, about 0.1 wt.%, about 0.5 wt.%, about 1 wt.%, about 2 wt.%, about 3 wt.%, about 4 wt.%, or about 5 wt.%, based on the total weight of the composition.

[0065] Without wishing to be bound by theory, it is believed that the phosphoric acid in combination with the organic-solvent based resin affords greater resistance to water degradation (i.e., degradation of phase 5 magnesium oxychloride (MOC)) for any cementitious articles formed from the composition. Thus, the inclusion of phosphoric acidmay be advantageous in compositions for forming benchtops and the like, since such cementitious articles are exposed to substantial amounts of water during their lifecycle.

[0066] In some embodiments, the composition further comprises a decorative additive. Suitable decorative additives would be known to persons skilled in the art in relation to the cementitious article to be formed. In some embodiments, the decorative additive is selected from the group consisting of an epoxy flake, a recycled plastic, and any combination thereof. In some embodiments, the decorative additive is an epoxy flake. In some embodiments, the decorative additive is a recycled plastic. In some embodiments, the decorative additive is a combination of an epoxy flake and a recycled plastic. The recycled plastic may be any recycled plastic suitable for improving an aesthetic appeal of any cementitious article formed from the composition. For example, the recycled plastic may be recycled high-density polyethylene (HDPE) (e.g., shredded HDPE). The inclusion of recycled plastic in the composition represents an environmentally friendly use of plastic waste materials.

[0067] In some embodiments, the decorative additive has a particle size of less than about 100 mm, less than about 50 mm, less than about 15 mm, less than about 10 mm, or less than about 5 mm. In some embodiments, the decorative additive has a particle size of less than about 100 mm. In some embodiments, the decorative additive has a particle size of less than about 50 mm. In some embodiments, the decorative additive has a particle size of less than about 15 mm. In some embodiments, the decorative additive has a particle size of less than about 10 mm. In some embodiments, the decorative additive has a particle size of less than about 5 mm.

[0068] In some embodiments, the decorative additive is present in amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 5 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition. In some embodiments, the decorative additive is present in amount of from about 0.1 wt.% to about 10 wt.% based on the total weight of the composition. In some embodiments, the decorative additive is present in amount of from about 1 wt.% to about 5 wt.% based on the total weight of the composition. In some embodiments, the decorative additive is present in amount of from about 1 wt.% to about 3 wt.% based on the total weight of the composition. For example, the decorative additive may be present in amount of about 0.1 wt.%, about 0.5 wt.%, about 1 wt.%, about2 wt.%, about 3 wt.%, about 4 wt.%, about 5 wt.%, about 6 wt.%, about 7 wt.%, about 8 wt.%, about 9 wt.%, or about 10 wt.%, based on the total weight of the composition.

[0069] In some embodiments, the composition further comprises a hydrophobic additive. Suitable hydrophobic additives would be known to persons skilled in the art in relation to the applicable organic solvent-based resin. For example, the hydrophobic additive may be, by way of non-limiting example, a silicone-based hydrophobic additive, a wax hydrophobic additive, or a combination thereof. In some embodiments, the hydrophobic additive is a silicone-based hydrophobic additive (e.g., DOWSIL™ SHP 60 Plus (commercially available from Dow Chemical Company; Midland, Michigan, United States of America)). In some embodiments, the hydrophobic additive is a wax. In some embodiments, the hydrophobic additive comprises a silicone-based hydrophobic additive and a wax.

[0070] In some embodiments, the hydrophobic additive is present in an amount of from about 0.1 wt.% to about 4 wt.%, from about 1 wt.% to about 3 wt.%, or from about 1 wt.% to about 2 wt.% based on the total weight of the composition. In some embodiments, the hydrophobic additive is present in an amount of from about 0.1 wt.% to about 4 wt.% based on the total weight of the composition. In some embodiments, the hydrophobic additive is present in an amount of from 1 wt.% to about 3 wt.% based on the total weight of the composition. In some embodiments, the hydrophobic additive is present in an amount of from about 1 wt.% to about 2 wt.% based on the total weight of the composition. For example, the hydrophobic additive maybe present in an amount of from about 0.1 wt.%, about 0.5 wt.%, about 1 wt.%, about 2 wt.%, about 3 wt.%, or about 4 wt.%, based on the total weight of the composition.

[0071] In some embodiments, the composition further comprises a plasticizer, e.g., a superplastizer. Suitable plasticizers would be known to persons skilled in the art in relation to the applicable organic solvent-based resin. For example, the plasticizer may be, by way of non-limiting example, a phthalate, a hydrogenated phthalate, an aliphatic esters of a dicarboxylic acid, a polymeric ester of a dicarboxylic acid, a citric acid salt, a sucrose ester, a levulinic ketal ester, a phosphates, an alkylphenol sulfonate, a pyrrolidone, or any combination thereof. In some embodiments, the plasticizer is a superplasticizer. Suitable superplasticizers include, by way on non-limiting example, sulfonated melamineformaldehyde condensates (SMF), sulfonated naphthalene-formaldehyde condensates(SNF), modified lignosulfonates (MLS), polycarboxylate (e.g. acrylic) superplasticizers (PCS; e.g., Sika® ViscoCrete®-3110 (commercially available from Sika GCC; Dubai, United Arab Emirates)), and combinations thereof.

[0072] In some embodiments, the plasticizer (e.g., the superplasticizer) is present in an amount of from about 0.1 wt.% to about 5 wt.%, from about 1 wt.% to about 4 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition. In some embodiments, the plasticizer is present in an amount of from about 0.1 wt.% to about 5 wt.% based on the total weight of the composition. In some embodiments, the plasticizer is present in an amount of from about 1 wt.% to about 4 wt.% based on the total weight of the composition. In some embodiments, the plasticizer is present in an amount of from about1 wt.% to about 3 wt.% based on the total weight of the composition. For example, the plasticizer may be present in amount of about 0.1 wt.%, about 0.5 wt.%, about 1 wt.%, about2 wt.%, about 3 wt.%, about 4 wt.%, or about 5 wt.%, based on the total weight of the composition.

[0073] In some embodiments, the composition further comprises a defoamer. Suitable defoamers would be known to persons skilled in the art in relation to the applicable organic solvent-based resin. For example, the defoamer may be, by way of non-limiting example, a silicone-based defoamer, a polyether-based defoamer, a fatty acid-based defoamer, or any combination thereof. In some embodiments, the defoamer is a silicone-based defoamer (e.g., ANTIFOAM; commercially available from Agar Pty Ltd; Preston, Victoria, Australia). In some embodiments, the defoamer is a poly ether-based defoamer. In some embodiments, the defoamer is a fatty acid-based defoamer.

[0074] In some embodiments, the defoamer is present in an amount of from about 0.1 wt.% to about 4 wt.%, from about 0.5 wt.% to about 2.5 wt.%, or from about 1 wt.% to about 2 wt.% based on the total weight of the composition. In some embodiments, the defoamer is present in an amount of from about 0.1 wt.% to about 4 wt.% based on the total weight of the composition. In some embodiments, the defoamer is present in an amount of from about 0.5 wt.% to about 2.5 wt.% based on the total weight of the composition. In some embodiments, the defoamer is present in an amount of from about 1 wt.% to about 2 wt.% based on the total weight of the composition. For example, the defoamer maybe present inan amount of from about 0.1 wt.%, about 0.5 wt.%, about 1 wt.%, about 2 wt.%, about 3 wt.%, or about 4 wt.%, based on the total weight of the composition.

[0075] In some embodiments, the composition comprises 5 wt.% or less of any silicone- based additives (e.g., the hydrophobic additive and the defoamer). In some embodiments, the composition comprises 2.5 wt.% or less of any silicone-based additives. In some embodiments, the composition comprises 1 wt.% or less of any silicone-based additives. In some embodiments, the composition comprises 0.1 wt.% or less of any silicone-based additives. In some embodiments, the composition is free of any silicone-based additives.

[0076] In some embodiments, the composition is substantially free (i.e., comprises less than about 5 wt.%, less than about 2.5 wt.%, less than about 1 wt.%, or less than about 0.1 wt.%) of silica (SiC>2 (e.g., crystalline SiCh)). In some embodiments, the composition comprises less than about 5 wt.% of SiCh. In some embodiments, the composition comprises less than about 2.5 wt.% of SiCh. In some embodiments, the composition comprises less than about 1 wt.% of SiC>2. In some embodiments, the composition comprises less than about 0.1 wt.% of SiC>2. In some embodiments, the composition is free of SiCh. In such embodiments, the composition described herein reduces and / or prevents risk of silicosis associated with use of the compositions and any cementitious articles formed therefrom.

[0077] In some embodiments, the composition is free of a water-based resin.

[0078] In one aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The organic solvent-based resin is free of a siloxane moiety.

[0079] In another aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in anamount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition.

[0080] In a further aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The organic solvent-based resin is free of a siloxane moiety.

[0081] In one aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), an organic solvent-based resin, and at least one of an organic solvent, a dye, a catalyst, and a hardener. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition. In some embodiments, the polymer formed from the organic solvent-based resin and the at least one of the catalyst and the hardener is free of a siloxane moiety (i.e., a Si-O-Si moiety).

[0082] In another aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), an organic solvent-based resin, and at least one of an organic solvent, adye, a catalyst, and a hardener. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition. The organic solvent-based resin is free of a siloxane moiety. In some embodiments, the polymer formed from the organic solvent-based resin and the at least one of the catalyst and the hardener is free of a siloxane moiety (i.e., a Si-O-Si moiety).

[0083] In a further aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), an organic solvent-based resin, phosphoric acid, and at least one of an organic solvent, a dye, a catalyst, and a hardener. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition. In some embodiments, the phosphoric acid is about 85 wt.% phosphoric acid in H2O. In some embodiments, the phosphoric acid is present in an amount of from about 0.01 wt.% to about 5 wt. %, from about 0.1 wt.% to about 1.0 wt.%, or from about 0.1 wt.% to about 0.5 wt.% based on the total weight of the composition. In some embodiments, the polymer formed from the organic solvent-based resin and the at least one of the catalyst and the hardener is free of a siloxane moiety (i.e., a Si-O-Si moiety).

[0084] In one aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), an organic solvent-based resin, phosphoric acid, and at least one of an organic solvent, a dye, a catalyst, and a hardener. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition. The organic solvent-based resin is free of a siloxane moiety. In some embodiments, the phosphoric acid is about 85 wt.% phosphoric acid in H2O. In some embodiments, the polymer formed from the organic solvent-based resin and the at least one of the catalyst and the hardener is free of a siloxane moiety (i.e., a Si-O-Si moiety).

[0085] In another aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), an organic solvent-based resin, phosphoric acid, a filler, a decorative additive, and at least one of an organic solvent, a dye, a catalyst, and a hardener. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition. The organic solvent-based resin is free of a siloxane moiety. The filler is present in an amount of from about 0.1 wt.%to about 10 wt.%, from about 1 wt.% to about 7.5 wt.%, or from about 1 wt.% to about 5 wt.% based on the total weight of the composition. The decorative additive is present in amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 5 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition. In some embodiments, the phosphoric acid is about 85 wt.% phosphoric acid in water (H2O). In some embodiments, the organic solvent-based resin is selected from the group consisting of an epoxy resin, a polyester resin, an acrylic resin, and any combination thereof. In some embodiments, the polymer formed from the organic solvent-based resin and the at least one of the catalyst and the hardener is free of a siloxane moiety (i.e., a Si-O-Si moiety).

[0086] In a further aspect, the present disclosure provides a composition for forming a cementitious article. The composition comprises magnesium oxide (MgO), magnesium chloride (MgCh), an organic solvent-based resin, a filler, a decorative additive, and at least one of an organic solvent, a dye, a catalyst, and a hardener. The MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh). The MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The MgCh is present in an aqueous solution, and the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition. The organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.% or from about 10 wt.% to about 15 wt.% based on the total weight of the composition. The organic solvent-based resin is free of a siloxane moiety. The filler is present in an amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 7.5 wt.%, or from about 1 wt.% to about 5 wt.% based on the total weight of the composition. The decorative additive is present in amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 5 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition. In some embodiments, the organic solventbased resin is selected from the group consisting of an epoxy resin, a polyester resin, an acrylic resin, and any combination thereof. In some embodiments, the polymer formed from the organic solvent-based resin and the at least one of the catalyst and the hardener is free of a siloxane moiety (i.e., a Si-O-Si moiety).

[0087] In one aspect, the present disclosure broadly relates to a cementitious article formed from any composition described herein. Such cementitious articles may be suitable for use in construction materials. For example, the construction materials may be non-structural materials (e.g., benchtops, tiles or panels) or structural materials (e.g., frames, trusses, nogs, or the like). Thus, in some embodiments, the cementitious article is a benchtop, a tile, a panel, a frame, a truss, a nog, a load-bearing member, a stud, a lintel, or a ledger. In some embodiments, the cementitious article is a benchtop. In some embodiments, the cementitious article is a tile. In some embodiments, the cementitious article is a panel. In some embodiments, the cementitious article is a frame. In some embodiments, the cementitious article is a truss. In some embodiments, the cementitious article is a nog. In some embodiments, the cementitious article is a load-bearing member. In some embodiments, the cementitious article is a stud (e.g., a jack stud, a jamb stud, a common stud, etc.). In some embodiments, the cementitious article is a lintel. In some embodiments, the cementitious article is a ledger. When the cementitious article is a frame, the frame may comprise various additional members, such as studs. Other suitable cementitious articles that may be formed using the compositions disclosed herein would be apparent those skilled in the art.

[0088] In some embodiments, a sealant is disposed on an exterior surface of the cementitious article. The sealant may be disposed on an exterior surface so as to at least partially coat the exterior surface of the cementitious article with the sealant. Preferably, the sealant is disposed on an exterior surface so as to coat substantially the entire exterior surface of the cementitious article with the sealant. The sealant is not particularly limited and may be any sealant suitable for reducing or preventing water penetration into the cementitious article. Examples of suitable sealants may include, but are not limited to, a polyurethane sealant, an acrylic sealant, an epoxy sealant, a hydrocarbon sealant, a vinyl ester sealant, a polysulfide sealant, a silicone sealant, or any combination thereof. In such embodiments, the sealant further reduces or prevents degradation of phase 5 MOC present in the cementitious article.

[0089] In some embodiments, the cementitious article has a flexural strength of from about 4 MPa to about 20 MPa. In some embodiments, the cementitious article has a flexural strength of from about 5 MPa to about 15 MPa. In some embodiments, the cementitious article has a flexural strength of from about 6 MPa to about 12 MPa. In some embodiments, the cementitious article has a flexural strength of from about 7 MPa to about 12 MPa. Insome embodiments, the cementitious article has a flexural strength of from about 8 MPa to about 12 MPa. The terms “flexural strength” and “flexural stress” are used interchangeably herein.

[0090] In some embodiments, the cementitious article has a Young's modulus of from about 1,000 MPa to about 4,000 MPa. In some embodiments, the cementitious article has a Young's modulus of from about 1,250 MPa to about 4,000 MPa. In some embodiments, the cementitious article has a Young's modulus of from about 1,500 MPa to about 4,000 MPa. In some embodiments, the cementitious article has a Young's modulus of from about 1,750 MPa to about 4,000 MPa. In some embodiments, the cementitious article has a Young's modulus of from about 2,000 MPa to about 4,000 MPa. In some embodiments, the cementitious article has a Young's modulus of from about 2,250 MPa to about 4,000 MPa. In some embodiments, the cementitious article has a Young's modulus of from about 2,500 MPa to about 4,000 MPa. Young’ s modulus is a value used to demonstrate a material's resistance to elastic deformation / permanent-plastic deformation. Accordingly, the greater the Young’s modulus, the more stress that can be applied to a sample without permanently changing its shape.

[0091] In some embodiments, the cementitious article has a water absorption of less than about 10%, less than about 7.5%, less than about 5%, or less than about 2.5% after submersion in water for 28 days. In some embodiments, the cementitious article has a water absorption of less than about 10% after submersion in water for 28 days. In some embodiments, the cementitious article has a water absorption of less than about 7.5% after submersion in water for 28 days. In some embodiments, the cementitious article has a water absorption of less than about 5% after submersion in water for 28 days. In some embodiments, the cementitious article has a water absorption of less than about 2.5% after submersion in water for 28 days. In the context of this disclosure, water absorption is calculated in accordance with Equation [3] : Water Absorption ( 100[3], wherein:mi is an initial mass (g) of the cementitious article prior to submersion in water for 28 days; and m2 is a mass (g) of the cementitious article after submersion in water for 28 days.

[0092] Without wishing to be bound by theory, it is believed that MOC present in the cementitious articles described herein may uptake carbon dioxide (CO2) in an atmosphere surrounding the cementitious articles, thereby reducing an amount of greenhouse gases present in the atmosphere. In other words, the cementitious articles described herein may act as a CO2 sink, advantageously removing CO2 from the surrounding atmosphere.

[0093] The cementitious articles disclosed herein may be formed using any suitable method and equipment. In one aspect, the present disclosure broadly relates to a method of forming a cementitious article, the method comprising: a) mixing magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin to form a cementitious mixture, wherein the MgO and the MgCh are present in the cementitious mixture at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh) (e.g., a composition as described herein); b) disposing the cementitious mixture in a mould; and c) allowing the cementitious mixture to cure in the mould, thereby forming the cementitious article.

[0094] In some embodiments, mixing step a) further comprises mixing the MgO, the MgCh, the organic solvent-based resin, and at least one of a filler, phosphoric acid, a hydrophobic additive, a decorative additive, a plasticizer (e.g., a superplasticizer), and a defoamer. The filler, phosphoric acid, hydrophobic additive, decorative additive, plasticizer, and / or defoamer may be any filler, phosphoric acid, hydrophobic additive, decorative additive, plasticizer, and / or defoamer described herein. In some embodiments, mixing step a) is performed in a mixer (e.g., a tank mixer).

[0095] In some embodiments, mixing step a) further comprises: a-1) mixing the MgO and the MgCh to form a pre-cementitious mixture; a-2) mixing an organic solvent-based resin and at least one of an organic solvent, a dye, a catalyst, and a hardener to form an organic solvent-based resin mixture; and a-3) mixing the pre-cementitious mixture and the organic solvent-based resin mixture to form the cementitious mixture.

[0096] In some embodiments, mixing step a) further comprises: a-1) mixing the MgO, the MgCh, and at least one of a filler, phosphoric acid, a hydrophobic additive, a decorative additive, a plasticizer (e.g., a superplasticizer), and a defoamer to form a pre-cementitious mixture; a-2) mixing an organic solvent-based resin and at least one of an organic solvent, a dye, a catalyst, and a hardener to form an organic solvent-based resin mixture; and a-3) mixing the pre-cementitious mixture and the organic solvent-based resin mixture to form the cementitious mixture.

[0097] In some embodiments, mixing steps a-1) and a-2) are performed separate mixers (e.g., separate tank mixers). In some embodiments, mixing step a-3) is performed in one of the mixers used in mixing steps a-1) and a-2). In some embodiments, mixing step a-3) is performed in a mixer that is different from the mixers used in mixing steps a-1) and a-2).

[0098] In some embodiments, all of the cementitious mixture is disposed in the mould in step b). In some embodiments, disposing step b) further comprises: b-1) disposing a first portion of the cementitious mixture in a mould; and b-2) disposing a second portion of the cementitious mixture in the mould after the first portion.The sequential addition of the cementitious mixture to the mould may reduce the formation of air bubbles that may deleteriously impact the uniformity and structural integrity of the resultant cementitious article.

[0099] In some embodiments, curing step c) comprises allowing the cementitious mixture to cure for at least 12 hours, at least 1 day, at least 2 days, at least 3 days, at least 4 days, at least 5 days, at least 6 days, or at least 7 days. In some embodiments, curing step c) is performed at ambient temperature, pressure, and humidity.

[0101] In some embodiments, the method further comprises: d) agitating the cementitious mixture prior to step c).

[0102] In some embodiments, step d) comprises agitating the cementitious mixture in the mould prior to step c). In some embodiments, step d) comprises vibrating (e.g., with a vibration table) the cementitious mixture prior to step c). Agitation reduces and / or removes air bubbles present in the cementitious mixture.

[0103] In some embodiments, the method comprises: b-1) disposing a first portion of the cementitious mixture in a mould; b-2) agitating the first portion of the cementitious mixture in the mould; b-3) disposing a second portion of the cementitious mixture in the mould after step b-2); and b-4) agitating the first and second portions of the cementitious mixture in the mould prior to step c).

[0104] In some embodiments, the method further comprises: e) cutting and / or polishing the cementitious article after step c).

[0105] In some embodiments, step e) comprises cutting and polishing the cementitious article after step c). In some embodiments, step e) comprises cutting the cementitious article after step c). In some embodiments, step e) comprises polishing the cementitious article after step c). When step e) comprises cutting the cementitious article, the cutting may be performed with any suitable cutting apparatus. For example, the cutting may be performed with a diamond grinder or a saw (e.g., a table saw). When step e) comprises polishing the cementitious articles, the polishing may be performed with any suitable sandpaper, grinders, and / or polishing pads. In some embodiments, the polishing is performed with about 1-grit to about 1,000 grit sandpaper, polishing pads, and / or grinders. In some embodiments, the polishing is performed with 60-grit sandpaper, 50-grit honeycomb polishing pads, 200-grit resin-based polishing pads, and / or 800-grit resin-based polishing pads.

[0106] In some embodiments, the method further comprises: f) disposing a sealant on an exterior surface of the cementitious article after step c).

[0107] The sealant of step f) may be any sealant described herein. In some embodiments, step f) is performed prior to step e). In some embodiments, step f) is performed after step e). As described elsewhere herein, the sealant may be disposed on the exterior surface of the cementitious article so as to at least partially coat the exterior surface, preferably coat substantially the entire exterior surface of, the cementitious article with the sealant. The sealant may be applied using any suitable method known in the art, such as via a high volume, low pressure (HVLP) spray systems or an airless spray systems.

[0108] Those skilled in the art will be aware that the disclosure provided herein is subject to variations and modifications other than those specifically described. It is to be understood that the disclosure provided herein includes all such variations and modifications. The present disclosure also includes all such steps, features, methods, compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations of any two or more of said steps or features.

[0109] Certain embodiments of the disclosure will now be described with reference to the following examples which are intended for the purpose of illustration only and are not intended to limit the scope of the generality hereinbefore described.EXAMPLESExample 1. Water Absorption Test for Compositions Comprising Water-Based or Organic Solvent-Based ResinsMaterials and Methods

[0110] All equipment was cleaned with distilled water prior to the preparation of any samples. The mould was coated with an oil and water releasing agent prior to use.

[0111] Preparation of Aqueous Magnesium Chloride (MgCh) Solution: The aqueous MgCh solution of Sample 1 was prepared such that the water (H2O) and the MgCh were present at a molar ratio of 11 : 1 (H2O : MgCh). The aqueous MgCh solutions of all other samples were prepared such that the H2O and MgCh were present at a molar ratio of 12: 1 (H2O : MgCh).

[0112] Preparation of Magnesium Oxide (MgO): For each sample, an appropriate amount of MgO was weighed such that the MgO and MgCh were present at a molar ratio of 7: 1 (MgO : MgCh).

[0113] Other Additives: Other additives (wt.% based on the total weight of the sample) were added to each sample. Resins used were Crommelin® DiamondCoat Exposed Aggregate & Polished Concrete Sealer (an organic solvent-based resin commercially available from Crommelin; Welshpool, Western Australia, Australia), ARDEX WPM 300 (a water-based epoxy resin commercially available from Ardex Australia Pty Ltd; Seven Hills, NSW, Australia), and Gripset P39 (a water-based polyurethane resin commerciallyavailable from Gripset Industries; Wingfield, South Australia, Australia). For the organic- solvent based resin, approximately 120 mL was used in the corresponding samples. For the water-based epoxy resin, approximately 75 mL of Part A (103.5 g) and 75 mL of Part B (94.5 g) was used in the corresponding samples. For the water-based polyurethane resin, approximately 150 mL (195 g) was used in the corresponding samples.

[0114] Phosphoric acid (85 wt.% phosphoric acid in H2O) was used in some samples at an amount of 1 wt.% relative to the MgO present in the sample. A superplasticizer (Sika® ViscoCrete®- 10 (commercially available from Sika GCC; Dubai, United Arab Emirates)) was used in all samples at an amount of ~15 mL / kg of the resultant composition (excluding any defoamer used). A defoamer (commercially available from Agar Pty Ltd; Preston, Victoria, Australia) was also used in all samples at an amount of approximately 1 wt.%. Fillers used were cellulose (TECHNOCEL® 200-1, commercially available from CFF GmbH & Co.; Ilmenau, Germany) and recycled, shredded high density polyethylene (HDPE; particle size of less than 5 mm). The recycled, shredded HDPE also served as a decorative additive. A hydrophobic additive was also used in certain samples (DOW SIL™ SHP 60 Plus (commercially available from Dow Chemical Company; Midland, Michigan, United States of America)).

[0115] Method of Making Cementitious Articles: After measuring the appropriate amounts of each component for each sample, the dry components were mixed in a bucket so that a uniform distribution was established. The mixture of dry components was then manipulated with a scraper to form a well (i.e., void space) in the middle of the bucket. The aqueous MgCh solution and superplasticizer were then added to the well, and the resultant mixture was mixed with a drill equipped with a mixing attachment until a cake-like mixture was formed. Approximately 1 wt.% of the defoamer was then added, and mixing continued with the drill equipped with the mixing attachment. The corresponding resin was then added to the bucket with mixing until all components were mixed.

[0116] Resultant samples were then transferred to the mould. Initially, the mould was filled to a quarter of its total capacity. The mould was placed on a vibration table until there were no visible air bubbles present in the sample. This process of sample addition followed by vibration was repeated until the mould was fully filled. Each sample in the mould was thenallowed to settle and dry (i.e., cure) for 24 hours (hrs). All samples were cured at atmospheric pressure, room temperature, and humidity.

[0117] Water Absorption Measurements: The resultant cementitious articles were cut with a diamond grinder or a table saw (the diamond grinder was used for samples containing phosphoric acid). The cut samples were then sanded with an orbital sander in the following order: 60-grit sandpaper, 50-grit honeycomb polishing pads, 200-grit resin-based polishing pads, followed by 800-grit resin-based polishing pads. The length, width, and height of each sample were then determined with a vernier caliper, the mass was recorded, and the volume and density were calculated.

[0118] Samples were then submerged in water (tap water) within a capped bucket for 28 days. Samples were removed from the water at approximately days 1, 7, 21, and 28, and the mass of each sample was recorded (after all sides of each sample were patted down with a paper towel).Results

[0119] A total of 7 samples were prepared. The components of each sample are provided in Table 1 below. Weights and ratios are provided in Table 2 below. Water absorption data for each sample is provided in Table 3 below. A graphical representation of water absorption of each of Samples 1-7 after submersion in water for approximately 28 days is shown in Figure 1.

[0120] Table 1: Samples 1-7 of Example 1.

[0121] Table 2: Weights and ratios for Samples 1-7 of Example 1

[0122] Table 3 : Water absorption after approximately 28 days for Samples 1-7 of Example 1.

[0123] Samples 1 and 2 exhibited a decrease in mass after submersion in water for 28 days. This decrease in mass is the result of mass loss, suggesting that water penetrated the cementitious articles and degraded the phase 5 MOC present in each sample. By way of example, a cementitious article according to Example 1, wherein the cementitious article is formed from a composition comprising MgO, MgCh, and a water-based resin (Sample 2), showed an observable loss of mass after submersion in water for 28 days that is consistent with degradation of magnesium oxychloride (MOC) present in the cementitious article.

[0124] Samples 1 -3 and 5 each showed substantial signs of water degradation (i.e., cracking, mass loss, etc.). The phosphoric acid included in Sample 6 appeared to both decrease the initial rate of water permeation and also improve the structural integrity of MOC when exposed water. Sample 7 exhibited a delayed onset of physical degradation, despite exhibiting a large water absorption.

[0125] Additionally, Samples 1-5 and 7, each including resins, were also examined for degradation without submersion in water. Samples 1-5 each exhibited degradation without submersion in water, whereas Sample 7 showed no signs of degradation. Samples 1-5 each included a water-based resin. In contrast, Sample 7 included an organic solvent-based resin.The superior performance of Sample 7 suggests that organic solvent-based resins are more suitable than water-based resins for forming MOC cementitious articles.Example 2. Water Absorption Test and 4-Point Bend Test for Compositions Comprising an Organic Solvent-Based Epoxy ResinMaterials and Methods

[0126] All equipment was cleaned with distilled water prior to the preparation of any samples. The mould was coated with an oil and water releasing agent prior to use.

[0127] Preparation of Aqueous Magnesium Chloride (MgCh) Solution: The aqueous MgCh solutions of all samples were prepared such that the H2O and MgCh were present at a molar ratio of 12: 1 (H2O : MgCh).

[0128] Preparation of Magnesium Oxide (MgO): For each sample, an appropriate amount of MgO was weighed such that the MgO and MgCh were present at a molar ratio of 7: 1 (MgO: MgCh).

[0129] Preparation of Organic Solvent-Based Resin Mixture: The organic solvent-based resin used was Trojan Fibreglass 1000 Series Epoxy High Clarity Resin (commercially available from Trojan Fibreglass; Cardiff, New South Wales, Australia). Part A (80 mL; -96.0 g) was mixed with Part B (40 mL; -36.8 g) for approximately 30 seconds until cloudiness dissipated. A polyester pigment (3 wt.% relative to the combined weight of Part A and Part B) was added with mixing until the polyester pigment was uniformly dispersed.

[0130] Other Additives: Other additives (wt.% based on the total weight of the sample) were added to each sample. Phosphoric acid (85 wt.% phosphoric acid in H2O) was used in some samples at an amount of 1 wt.% relative to the MgO present in the sample. The phosphoric acid was added to the aqueous MgCh solutions.

[0131] A superplasticizer (Sika® ViscoCrete®- 10 (commercially available from Sika GCC; Dubai, United Arab Emirates)) was used in all samples at an amount of -15 mL / kg of the resultant composition (excluding any defoamer used). A defoamer (commercially available from Agar Pty Ltd; Preston, Victoria, Australia) was also used in all samples at an amount of approximately 1 wt.%. Fillers used were cellulose (TECHNOCEL® 200-1, commercially available from CFF GmbH & Co.; Ilmenau, Germany) and recycled, shredded high densitypolyethylene (HDPE; particle size of less than 5 mm). Fillers were used in all samples. The recycled, shredded HDPE also served as a decorative additive. A hydrophobic additive was also used in all samples (DOWSIL™ SHP 60 Plus (commercially available from Dow Chemical Company; Midland, Michigan, United States of America)).

[0132] Method of Making Cementitious Articles: After measuring the appropriate amounts of each component for each sample, the dry components were mixed in a bucket so that a uniform distribution was established. The mixture of dry components was then manipulated with a scraper to form a well (i.e., void space) in the middle of the bucket. The aqueous MgCh solution and superplasticizer were then added to the well, and the resultant mixture was mixed with a drill equipped with a mixing attachment until a cake-like mixture was formed. Approximately 1 wt.% of the defoamer was then added, and mixing continued with the drill equipped with the mixing attachment. The resin was then added to the bucket with mixing until all components were mixed.

[0133] Each sample (i.e., Samples 8-13 of Table 4 below) was then transferred to a respective mould. Initially, the mould was filled to a quarter of its total capacity. The mould was placed on a vibration table until there were no visible air bubbles present in the sample. This process of sample addition followed by vibration was repeated until the mould was fully filled. The sample in the mould was then allowed to settle and dry (i.e., cure) for 24 hrs. The sample was cured at atmospheric pressure, room temperature, and humidity.

[0134] The sample was then removed from the mould and left for seven (7) days before cutting. The sample was cut into four (4) equal subsamples having dimensions of 150 mm x 50 mm x 20 mm. Surfaces of each subsample were grinded with 80 grit sandpaper.

[0135] Water Absorption Measurements: The length, width, and height of each subsample were determined with a vernier caliper, the mass was recorded, and the volume and density were calculated. Subsamples were then submerged in water (tap water) within a capped bucket for 28 days. Subsamples were removed from the water at approximately days 1, 7, 14, 21, and 28, and the mass of each subsample was recorded (after all sides of each subsample were patted down with a paper towel).

[0136] 4-Point Bend Test: Subsamples were dried for 24 hours after submersion. Subsamples were then subjected to a 4-point bend test with an Instron Universal TestingMachine (Model 4505) in accordance with ASTM D6272. The 4-point bend test was used to calculate both the flexural strength and Young's modulus of each subsample.

[0137] The length, width, and height of each subsample were determined with a vernier caliper. The testing apparatus was prepared based on 0.5 loading and support span ratio (80 mm support span, 40 mm loading span). Subsamples were placed on support pins such that there was equal overhang on each side. The loading span was dropped until slight contact was made with the subsample. Testing was conducted under the conditions of the load moving at a displacement rate of 0.50 mm / minute until material failure was manually or automatically detected.

[0138] Bluehill® Universal software automatically calculated the flexural strength based on Equation [4]:[4], wherein: or is the flexural strength (Pa);F is force (N);L is the support span (m); b is the width of the test beam (m); and d is the depth / thickness of the test beam (m) m2 is a mass (g) of the cementitious article after submersion in water for 28 days.Results

[0139] Samples 8-13 were prepared and cut into subsamples. Weights and ratios are provided in Table 4 below. Each subsample was then subjected to the water absorption test for 0, 1, 7, 14, 21, or 28 days, followed by the 4-point fold test. For instance, the subsamples of Sample 9 may have been submerged for 1 day, whereas the subsamples of Sample 10 may have been submerged for 7 days. Due to the similarity of Samples 8-13, the data is considered to approximate a single sample cut into 24 subsamples (i.e., 4 subsamples for each of the 6 time points (i.e., 0, 1, 7, 14, 21, and 28 days). Water absorption data for each subsample is provided in Table 5 below. Flexural strength data for each subsample isprovided in Table 6 below. Young's modulus (E) data for each subsample is provided in Table 7 below.

[0140] Table 4: Weights and ratios for Samples 8-13 of Example 2.

[0141] Table 5 : Water absorption for Subsamples 1-4 of the water absorption test of Example 2.

[0142] Table 6 : Flexural Strength for Subsamples 1-4 of the 4-point fold test of Example 2.

[0143] Table 7: Young's Modulus for Subsamples 1-4 of the 4-point fold test of Example 2.

[0144] With reference to Table 5 and Figure 2, water absorption of the samples increased for the first 21 days, achieving a maximum water absorption of 5.2973%. Between day 21 and day 28, water absorption decreased to 4.9559%, indicating that a critical water absorption level was reached in that period. The decrease in water absorption also suggests a loss of mass that is likely the result of MOC degradation in accordance with Equation [2], Specifically, degradation of MOC forms Mg(0H)2 and MgCh. While submerged, the MgCh is lost to the surrounding water, thereby resulting in a loss of mass of the cementitious article. After submersion in water an outer perimeter of the cross-sectioned samples had an observable discoloured appearance. This discolouration is indicative of Mg(0H)2 generation that is consistent with degradation of MOC present in the cementitious article, and is mostpronounced after submersion for 28 days. A graph of water penetration depth over time is provided in Figure 3. The data indicates that water penetration increased rapidly after submersion of the sample in water for 14 days.

[0145] The flexural strength of the sample was evaluated with the 4-point bend test. Maximum flexural strength of each sample decreased over the first 14 days, with the lowest flexural strength recorded at day 14 (5.88 MPa; 50.51% of the flexural strength at day 0). Loss of flexural strength correlated with an increase in water absorption, as shown in Figure 4, suggesting that MOC degradation impacted the flexural strength of the cementitious article. The increase in flexural strength from day 14 to day 28 may be attributable to strain hardening (Figures 5A-F).

[0146] With reference to Figure 6, Young's modulus decreased from day 1 to day 28. The observed increase in Young's modulus from day 0 to day 1 may have resulted from the increased number of samples (4 on day 1 as compared to 3 on day 0).

[0147] The samples of Example 2 also performed better than a control composition that was free of the organic solvent-based resin, cellulose, and HDPE. The control composition exhibited substantial observable degradation (i.e., cracking, mass loss, etc.) after only 5 days of water submersion. These results suggest that the inclusion of an organic solvent-based resin reduces MOC degradation, preserves the structural integrity of the cementitious article, and slows water absorption.Example 3. Water Absorption Test for Compositions Comprising an Organic Solvent- Based Epoxy Resin and Other AdditivesMaterials and Methods

[0148] All equipment was cleaned with distilled water prior to the preparation of any samples. The mould was coated with an oil and water releasing agent prior to use.

[0149] Preparation of Aqueous Magnesium Chloride (MgCh) Solution: The aqueous MgCh solutions of all samples were prepared such that the H2O and MgCh were present at a molar ratio of 12: 1 (H2O : MgCh).

[0150] Preparation of Magnesium Oxide (MgO): For each sample, an appropriate amount of MgO was weighed such that the MgO and MgCh were present at a molar ratio of 7: 1 (MgO : MgCh).

[0151] Preparation of Organic Solvent-Based Resin Mixture: The organic solvent-based resin used was Trojan Fibreglass 1000 Series Epoxy High Clarity Resin (commercially available from Trojan Fibreglass; Cardiff, New South Wales, Australia). Part A (80 mL; -96.0 g) was mixed with Part B (40 mL; -36.8 g) for approximately 30 seconds until cloudiness dissipated. A polyester pigment (3 wt.% relative to the combined weight of Part A and Part B) was added with mixing until the polyester pigment was uniformly dispersed.

[0152] Other Additives: Other additives (wt.% based on the total weight of the sample) were added to each sample. Phosphoric acid (85 wt.% phosphoric acid in H2O) was used in some samples at an amount of 1 wt.% relative to the MgO present in the sample. The phosphoric acid was added to the aqueous MgCh solutions.

[0153] A superplasticizer (Sika® ViscoCrete®- 10 (commercially available from Sika GCC; Dubai, United Arab Emirates)) was used in all samples at an amount of -15 mL / kg of the resultant composition (excluding any defoamer used). A defoamer (commercially available from Agar Pty Ltd; Preston, Victoria, Australia) was also used in all samples at an amount of approximately 1 wt.%. Fillers were used in some samples, and the fillers used were cellulose (TECHNOCEL® 200-1, commercially available from CFF GmbH & Co.; Ilmenau, Germany) and recycled, shredded high density polyethylene (HDPE; particle size of less than 5 mm). The recycled, shredded HDPE also served as a decorative additive. A hydrophobic additive was also used in all samples (DOW SIL™ SHP 60 Plus (commercially available from Dow Chemical Company; Midland, Michigan, United States of America)).

[0154] Method of Making Cementitious Articles: After measuring the appropriate amounts of each component for each sample, the dry components were mixed in a bucket so that a uniform distribution was established. The mixture of dry components was then manipulated with a scraper to form a well (i.e., void space) in the middle of the bucket. The aqueous MgCh solution and superplasticizer were then added to the well, and the resultant mixture was mixed with a drill equipped with a mixing attachment until a cake-like mixture was formed. Approximately 1 wt.% of the defoamer was then added, and mixing continuedwith the drill equipped with the mixing attachment. The resin was then added to the bucket with mixing until all components were mixed.

[0155] Resultant samples were then transferred to the mould. Initially, the mould was filled to a quarter of its total capacity. The mould was placed on a vibration table until there were no visible air bubbles present in the sample. This process of sample addition followed by vibration was repeated until the mould was fully filled. All samples were cured at atmospheric pressure, room temperature, and humidity.

[0156] After curing, the resultant cementitious articles were cut with a diamond grinder or a table saw (the diamond grinder was used for samples containing phosphoric acid) to a minimum size of 100 mm x 50 mm x 20 mm. The cut samples were then sanded with an orbital sander in the following order: 60-grit sandpaper, 50-grit honeycomb polishing pads, 200-grit resin-based polishing pads, followed by 800-grit resin-based polishing pads.

[0157] Water Absorption Measurements: The length, width, and height of each sample were determined with a vernier caliper, the mass was recorded, and the volume and density were calculated. Samples were then submerged in water (tap water) within a capped bucket for 28 days. Samples were removed from the water at approximately days 1, 8, 21, and 28, and the mass of each sample was recorded (after all sides of each sample were patted down with a paper towel).Results

[0158] Samples 14-17 were prepared. Weights and ratios are provided in Table 8 below.Water absorption data for each sample is provided in Table 9 below.

[0159] Table 8: Weights and ratios for Samples 14-17 of Example 3

[0160] Table 9: Water absorption for Samples 14-17 of Example 3.

[0161] With reference to Table 9 and Figure 7, Samples 14, 16, and 17 exhibited a water absorption of less than 5% after submersion in water for 28 days. However, Sample 14 exhibited substantial structural degradation after 28 days. Sample 15 also suffered fromsubstantial cracking, and even failure around day 22, which likely resulted in the increase in water absorption (i.e., a large crack along the surface of Sample 15 allowed water to penetrate interior regions of the cementitious article). Sample 16, which included phosphoric acid, showed minor surface cracking and discoloration after 28 days. Sample 17, which included phosphoric acid, cellulose, and HDPE, exhibited the least amount of structural damage and also good water absorption properties (4.46% at day 28). The results suggest that compositions comprising an organic solvent-based resin and fillers (i.e., cellulose and HDPE) may be advantageous for cementitious articles that will be exposed to substantial amounts of water (e.g., benchtops).Example 4. Water Absorption Test for Compositions Comprising an Organic Solvent- Based Polyester Resin and Other AdditivesMaterials and Methods

[0162] All equipment was cleaned with distilled water prior to the preparation of any samples. The mould was coated with an oil and water releasing agent prior to use.

[0163] Preparation of Aqueous Magnesium Chloride (MgCh) Solution: The aqueous MgCh solutions of all samples were prepared such that the H2O and MgCh were present at a molar ratio of 12: 1 (H2O : MgCh).

[0164] Preparation of Magnesium Oxide (MgO): For each sample, an appropriate amount of MgO was weighed such that the MgO and MgCh were present at a molar ratio of 7: 1 (MgO : MgCh).

[0165] Preparation of Organic Solvent-Based Resin Mixture: The organic solvent-based resin used was Trojan Fibreglass Polyester Marine LSE40 Waxed Laminating Resin (commercially available from Trojan Fibreglass; Cardiff, New South Wales, Australia). 24 mL (~26.4g) of the resin and a catalyst (methyl ethyl ketone peroxide catalyst; 2 wt.% relative to the resin component of the composition) were mixed slowly for approximately 30 seconds to avoid excessive air entrapment. A polyester pigment (3 wt.% relative to the combined weight of resin and catalyst) was added with mixing until the polyester pigment was uniformly dispersed.

[0166] Other Additives: Other additives (wt.% based on the total weight of the sample) were added to each sample. Phosphoric acid (85 wt.% phosphoric acid in H2O) was used in some samples at an amount of 1 wt.% relative to the MgO present in the sample. The phosphoric acid was added to the aqueous MgCh solutions.

[0167] A superplasticizer (Sika® ViscoCrete®- 10 (commercially available from Sika GCC; Dubai, United Arab Emirates)) was used in all samples at an amount of ~15 mL / kg of the resultant composition (excluding any defoamer used). A defoamer (commercially available from Agar Pty Ltd; Preston, Victoria, Australia) was also used in all samples at an amount of approximately 1 wt.%. Fillers were used in some samples, and the fillers used were cellulose (TECHNOCEL® 200-1, commercially available from CFF GmbH & Co.; Ilmenau, Germany) and recycled, shredded high density polyethylene (HDPE; particle size of less than 5 mm). The recycled, shredded HDPE also served as a decorative additive. A hydrophobic additive was also used in all samples (DOW SIL™ SHP 60 Plus (commercially available from Dow Chemical Company; Midland, Michigan, United States of America)).

[0168] Method of Making Cementitious Articles: After measuring the appropriate amounts of each component for each sample, the dry components were mixed in a bucket so that a uniform distribution was established. The mixture of dry components was then manipulated with a scraper to form a well (i.e., void space) in the middle of the bucket. The aqueous MgCh solution and superplasticizer were then added to the well, and the resultant mixture was mixed with a drill equipped with a mixing attachment until a cake-like mixture was formed. Approximately 1 wt.% of the defoamer was then added, and mixing continued with the drill equipped with the mixing attachment. The resin was then added to the bucket with mixing until all components were mixed.

[0169] Resultant samples were then transferred to the mould. Initially, the mould was filled to a quarter of its total capacity. The mould was placed on a vibration table until there were no visible air bubbles present in the sample. This process of sample addition followed by vibration was repeated until the mould was fully filled. All samples were cured at atmospheric pressure, room temperature, and humidity.

[0170] After curing, the resultant cementitious articles were cut with a diamond grinder or a table saw (the diamond grinder was used for samples containing phosphoric acid) to a minimum size of 100 mm x 50 mm x 20 mm. The cut samples were then sanded with anorbital sander in the following order: 60-grit sandpaper, 5O-grit honeycomb polishing pads, 200-grit resin-based polishing pads, followed by 8OO-grit resin-based polishing pads.

[0171] Water Absorption Measurements: The length, width, and height of each sample were determined with a vernier caliper, the mass was recorded, and the volume and density were calculated. Samples were then submerged in water (tap water) within a capped bucket for 28 days. Samples were removed from the water at approximately days 1, 8, 21, and 28, and the mass of each sample was recorded (after all sides of each sample were patted down with a paper towel).Results

[0172] Samples 18-21 were prepared. Weights and ratios are provided in Table 10 below. Water absorption data for each sample is provided in Table 11 below.

[0173] Table 10: Weights and ratios for Samples 18-21 of Example 4.

[0174] Table 11: Water absorption for Samples 18-21 of Example 4.

[0175] With reference to Table 11 and Figure 8, Samples 18, 19, and 20 exhibited a water absorption of less than 5% after submersion in water for 28 days. Sample 18, which was free of any fillers (i.e., cellulose and HDPE) and phosphoric acid, demonstrated only slight discoloration after 28 days and a water absorption of 2.48%. Sample 19 showed a water absorption of 3.09% after only 8 days, despite showing minimal surface degradation (i.e., no cracking). The increased water absorption may potentially be attributable to cellulose, which has strong water absorption properties. Sample 20 was significantly discoloured after 28 days of submersion, although the surface of the cementitious article remained free of cracking. Sample 21 exhibited the highest water absorption at each measured time point. However, only a slight discoloration was observed for Sample 21, and the surface remained free of any signs of degradation. Moreover, the steady plateau for Sample 21 in Figure 8 suggests a low MOC decomposition rate that may be advantageous for benchtop applications.

[0176] The results suggest that organic solvent-based polyester resins may be suitable for cementitious articles that will be exposed to substantial amounts of water (e.g., benchtops).Moreover, and without wishing to be bound by theory, it is believed that presence of phosphoric acid and fillers (cellulose and HDPE) may increase water absorption while reducing MOC decomposition rate.Example 5. Optimisation of HzO / MgCh ratio

[0177] The compressive properties of a magnesium-oxychloride formulation with EhO / MgCh ratios of 12-16.5: 1 was tested with a constant MgO / MgCh ratio of 7: 1 mole ratios to determine the optimum H2O / MgCh ratio for use in Examples 1-4 above.Materials and Methods

[0178] All equipment was cleaned with distilled water prior to the preparation of any samples. The mould was coated with an oil and water releasing agent prior to use.

[0179] Preparation of Aqueous Magnesium Chloride (MgCh) Solution: The aqueous MgCh solutions of all samples were prepared such that the H2O and MgCh were present at a molar ratios of 12: 1, 13.5: 1. 14.5: 1, 15.5: 1 and 16.5: 1 (H2O : MgCh).

[0180] Preparation of Magnesium Oxide (MgO): For each sample, an appropriate amount of MgO was weighed such that the MgO and MgCh were present at a molar ratio of 7: 1 (MgO: MgCh).

[0181] Additives: Additives (wt.% based on the total weight of the sample) were added to each sample. Sawdust was used in all samples at an amount of approximately 7.5 wt.%. Perlite (commercially available from Exfoliators (Aust) Pty Ltd) was used in all samples at an amount of approximately 4.5 wt.%. Fly ash (commercially available from Cement Australia) was also used in all samples at an amount of approximately 7.5 wt.%.

[0182] A superplasticizer (Easy Mix Mortar Aid; commercially available from Runnings Warehouse) was used in all samples at an amount of approximately 1 wt.%. A defoamer (commercially available from Agar Pty Ltd; Preston, Victoria, Australia) was also used in all samples at an amount of approximately 1 wt.%.

[0183] Method of Making Cementitious Articles: After measuring the appropriate amounts of each component for each sample, the dry components were mixed in a bucket so that a uniform distribution was established. The mixture of dry components was thenmanipulated with a scraper to form a well (i.e., void space) in the middle of the bucket. The aqueous MgCh solution and superplasticizer were then added to the well, and the resultant mixture was mixed with a drill equipped with a mixing attachment until a cake-like mixture was formed. Approximately 1 wt.% of the defoamer was then added, and mixing continued with the drill equipped with the mixing attachment.

[0184] Each sample (i.e., Samples 22-26 of Table 12 below) was then transferred to a respective mould. Initially, the mould was filled to a quarter of its total capacity. The mould was manually agitated until there were no visible air bubbles present in the sample. This process of sample addition followed by agitation was repeated until the mould was fully filled. The sample in the mould was then allowed to settle and dry (i.e., cure) for 24 hrs. The sample was cured at atmospheric pressure, room temperature, and humidity.

[0185] The sample was then removed from the mould and left for seven (7) days before cutting. The sample was cut into four (4) equal subsamples having dimensions of 150 mm x 50 mm x 20 mm. Surfaces of each subsample were grinded with 80 grit sandpaper.

[0186] Compressive strength: Subsamples were subjected to compression testing using an Instron Universal Testing Machine (Model 4505) fitted with the compression fixture adapter set to determine both the compressive strength and Young's modulus of each subsample.

[0187] The length, width, and height of each subsample were determined with a vernier caliper. Subsamples were placed beneath a compression platen. The compression was plate was moved down until the measured force increases from a negative value, to zero, indicating pressure between the upper platen and sample. Compression was then applied at a rate of 30 MPa / min until the subsamples buckled under compression and a significant decrease in measured force was observed.

[0188] Bluehill® Universal software automatically plotted a stress-strain diagram, from which features such as elastic limit, proportional limit, yield point, yield strength and compressive strength could be determined. Young's modulus was calculated based on Equations [5]-[7] :wherein:GCis the compressive strength (Pa);F is force (N); andA (m2) is the cross-sectional area of the material where the force is acting upon.AL8 = — L[6], wherein: a is the strain of the material;AL is the displacement (mm); andL is the initial length of material (mm).[7], wherein:E (Pa) is the Young's modulus.

[0189] Results

[0190] Samples 22-26 were prepared and cut into subsamples. Weights and ratios are provided in Table 12 below. Each subsample was then subjected to compression testing. Compression strength (Pa) for each subsample is provided in Table 13 below and Young's modulus (E) data is provided in Table 14 below.

[0191] Table 12: Weights and ratios for Samples 22-26 of Example 5.

[0192] Table 13: Compressive Strength for Subsamples 1-4 at different H2O : MgCh molar ratios of Example 5.

[0193] Table 14: Young's Modulus (E) for Subsamples 1-4 at different H2O : MgCh molar ratios of Example 5.

[0194] With reference to Tables 13 and 14, and Figures 9 and 10, a EbO / MgCh mole ratio of 12: 1 provided the optimal strength properties of all samples studied. The tests conducted show a consistent decrease in the average maximum compressive strength as the EEO / MgCh mole ratio increases (Figures 9 and 10). The large standard deviation observed for some test samples was believed to be due to, at least in part, to air bubbles within the final samples, which were minimised in Examples 1-4 by casting sample mould using a vibration table (as opposed to manual agitation).

Claims

CLAIMS1. A composition for forming a cementitious article, the composition comprising: magnesium oxide (MgO); magnesium chloride (MgCh), wherein the MgO and the MgCh are present at a molar ratio of from about 5: 1 to about 9: 1 (MgO: MgCh); and an organic solvent-based resin.

2. The composition of claim 1, wherein the MgO and the MgCh are present at a molar ratio of from about 6: 1 to about 8: 1, from about 6.5: 1 to about 7.5: 1, or about 7: 1.

3. The composition of claim 1 or claim 2, wherein the MgO is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition.

4. The composition of any one of claims 1-3, wherein the MgCh is present in an aqueous solution.

5. The composition of claim 4, wherein the aqueous solution of MgCh is present in an amount of from about 20 wt.% to about 60 wt.%, from about 30 wt.% to about 50 wt.%, or from about 35 wt.% to about 45 wt.% based on the total weight of the composition.

6. The composition of claim 4 or claim 5, wherein water (H2O) and the MgCh are present in the aqueous solution at a molar ratio of from about 10: 1 to about 15: 1, from about 11 : 1 to about 14: 1, from about 11 : 1 to about 13: 1, or about 12: 1 (H2O : MgCh).

7. The composition of any one of claims 1-6, wherein the organic solvent-based resin is free of a siloxane moiety.

8. The composition of any one of claims 1-7, wherein the organic solvent-based resin is selected from the group consisting of an epoxy resin, a polyester resin, a phenolic resin, an alkyd resin, an acrylic resin, a vinyl resin, a polyacetal resin, a polyurethane resin, an amino resin, an aldehyde resin, a maleic resin, a ketonic resin, a polyamide resin, a cellulose resin, and any combination thereof, preferably wherein the organic solvent-based resin is selected from the group consisting of an epoxy resin, a polyester resin, an acrylic resin, and any combination thereof.

9. The composition of any one of claims 1-8, wherein the composition further comprises at least one of an organic solvent, a dye, a catalyst, and a hardener, preferably wherein the organic solvent-based resin and the at least one of the organic solvent, the dye, the catalyst, and the hardener are present in a combined amount of from about 5 wt.% to about 25 wt.%, from about 7.5 wt.% to about 20 wt.%, or from about 10 wt.% to about 15 wt.% based on the total weight of the composition.

10. The composition of any one of claims 1-9, wherein the composition further comprises a filler, preferably wherein the filler is selected from the group consisting of cellulose or a derivative thereof, glass, sawdust, wood chips, and any combination thereof, further preferably wherein the filler is present in an amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 7.5 wt.%, or from about 1 wt.% to about 5 wt.% based on the total weight of the composition.

11. The composition of any one of claims 1-10, wherein the composition further comprises phosphoric acid, preferably wherein the phosphoric acid is about 85 wt.% phosphoric acid in water (H2O), further preferably wherein the phosphoric acid is present in an amount of from about 0.01 wt.% to about 5 wt.%, from about 0.1 wt.% to about 1.0 wt.%, or from about 0.1 wt.% to about 0.5 wt.% based on the total weight of the composition.

12. The composition of any one of claims 1-11, wherein the composition further comprises a decorative additive, preferably wherein the decorative additive is selected from the group consisting of an epoxy flake, a recycled plastic, and any combination thereof, further preferably wherein the decorative additive is present in amount of from about 0.1 wt.% to about 10 wt.%, from about 1 wt.% to about 5 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition.

13. The composition of any one of claims 1-12, wherein the composition further comprises a hydrophobic additive, preferably wherein the hydrophobic additive is a silicone-based hydrophobic additive,further preferably wherein the hydrophobic additive is present in an amount of from about 0.1 wt.% to about 4 wt.%, from about 1 wt.% to about 3 wt.%, or from about 1 wt.% to about 2 wt.% based on the total weight of the composition.

14. The composition of any one of claims 1-13, wherein the composition further comprises a plasticizer, preferably wherein the plasticizer is present in an amount of from about 0.1 wt.% to about 5 wt.%, from about 1 wt.% to about 4 wt.%, or from about 1 wt.% to about 3 wt.% based on the total weight of the composition.

15. The composition of any one of claims 1-14, wherein the composition further comprises a defoamer, preferably wherein the defoamer is a silicone-based defoamer, further preferably wherein the defoamer is present in an amount of from about 0.1 wt.% to about 4 wt.%, from about 0.5 wt.% to about 2.5 wt.%, or from about 1 wt.% to about 2 wt.% based on the total weight of the composition.

16. The composition of any one of claims 1-15, wherein the composition comprises 5 wt.% or less of any silicone-based additives.

17. The composition of any one of claims 1-16, wherein the composition is substantially free of silica (SiCh).

18. The composition of any one of claims 1-17, wherein the composition is free of a water-based resin.

19. A cementitious article formed from the composition of any one of claims 1-18.

20. The cementitious article of claim 19, which is a benchtop, a tile, a panel, a frame, a truss, a nog, a load-bearing member, a stud, a lintel, or a ledger, preferably a benchtop.

21. The cementitious article of claim 19 or claim 20, wherein a sealant is disposed on an exterior surface of the cementitious article.

22. The cementitious article of any one of claims 32-35, wherein the cementitious article has:(i) a flexural strength of from about 4 MPa to about 20 MPa; and / or(ii) a Young's modulus of from about 1,000 MPa to about 4,000 MPa; and / or(iii) a water absorption of less than about 10%, less than about 7.5%, less than about 5%, or less than about 2.5% after submersion in water for 28 days.

23. A method of forming a cementitious article, the method comprising: a) mixing magnesium oxide (MgO), magnesium chloride (MgCh), and an organic solvent-based resin to form a cementitious mixture, wherein the MgO and the MgCh are present in the cementitious mixture at a molar ratio of from about 5: 1 to about 9: 1 (MgO : MgCh); b) disposing the cementitious mixture in a mould; and c) allowing the cementitious mixture to cure in the mould, thereby forming the cementitious article.

24. The method of claim 23, wherein mixing step a) further comprises mixing the MgO, the MgCh, the organic solvent-based resin, and at least one of a filler, a phosphoric acid, a hydrophobic additive, a decorative additive, a plasticizer, and a defoamer.

25. The method of claim 23, wherein mixing step a) further comprises: a-1) mixing the MgO and the MgCh to form a pre-cementitious mixture; a-2) mixing an organic solvent-based resin and at least one of an organic solvent, a dye, a catalyst, and a hardener to form an organic solvent-based resin mixture; and a-3) mixing the pre-cementitious mixture and the organic solvent-based resin mixture to form the cementitious mixture.

26. The method of claim 23, wherein mixing step a) further comprises: a-1) mixing the MgO, the MgCh, and at least one of a filler, a phosphoric acid, a hydrophobic additive, a decorative additive, a plasticizer, and a defoamer to form a pre- cementitious mixture; a-2) mixing an organic solvent-based resin and at least one of an organic solvent, a dye, a catalyst, and a hardener to form an organic solvent-based resin mixture; and a-3) mixing the pre-cementitious mixture and the organic solvent-based resin mixture to form the cementitious mixture.

27. The method of any one of claims 39-42, further comprising: d) agitating the cementitious mixture prior to step c); and / or e) cutting and / or polishing the cementitious article after step c); and / or f) disposing a sealant on an exterior surface of the cementitious article after step c).

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