Compositions, systems and methods for turbostratic graphene based mortar and concrete modifiers

Abstract

A graphene-based cement modifier is provided herein. The modifier includes graphene obtained via a flash joule heating process applied to a carbon source. A graphene-based cement is provided herein. The cement includes a graphene-based cement modifier including graphene obtained via a flash joule heating process applied to a carbon source; and a cement. A method of producing a graphene-based modifier modified cement is provided herein. The method includes providing the graphene-based modifier, wherein the graphene-based modifier includes graphene obtained via a flash joule heating process applied to a carbon source; and combining the graphene-based modifier with a cementitious material.

Description

COMPOSITIONS, SYSTEMS AND METHODS FOR TURBOSTRATIC GRAPHENE BASED MORTAR AND CONCRETE MODIFIERSTechnical Field

[0001] The embodiments disclosed herein relate to cement, concrete, and modifiers and admixtures for the same and, in particular, to compositions of graphene and graphene-based modifiers and admixtures for cement and methods of manufacture of the same.Introduction:

[0002] Cement is used as a binder in structural construction that gels when it comes in contact with water. Cement is used as an ingredient of mortar and concrete to construct concrete structures. Concrete is the second-most used material after water globally. Existing concrete structures are used to build roads, bridges, dams, walls, roofings, and more. These structures rely on the cement for basic structure. High quality and high performing cement is desirable to enable the design and for safe and efficient construction of these concrete structures.

[0003] Durability is a desired quality of concrete and mortar attributable, at least in part to the cement therein. The durability is understood as resistance to degradation of the concrete as indicated by the engineering properties of the concrete. For example, some existing concrete types may be prone to cracking and therefore exhibit low durability. Low durability can compromise the safety and life span of the concrete.

[0004] The durability may be affected by exposure to harsh environmental conditions, loading, weathering action, chemical attacks, and abrasion. In an example, poor durability can arise from corrosion of reinforcement bars within concrete and chemical deterioration originating from carbonation, chloride attack under wet conditions, sulfate attack, calcium leaching, and damage from freezing and thawing. In a further example, a suboptimal air content or air content outside a prescribed range may negatively impact the mechanical performance and durability of concrete. Cements of various types may have specific properties providing specific durability and these cements may be selected based on the application.

[0005] Furthermore, increases in prices of cement and related carbon emission taxes based on, at least, the demand for cement products and applications particularly in urban areas, increase the desire for optimizing concrete performance, strength, and longevity, to beneficially minimize cost and maximize efficiency.

[0006] Growing interest in sustainable technology has also encouraged the use of less carbon-intense materials in concrete. Cost and environmental concerns related to the use of Portland cement have also led to increased use of supplementary cementitious materials (SCMs) in existing concrete compositions. The use of SCMs is also supported by regulations at the local, state, and federal levels. Existing systems, directed to reducing greenhouse gas emissions anddecarbonizing, include those using blends of SCMs that contribute to the properties of hardened concrete through pozzolanic activity. Typical examples are slag cement, fly ash, ground granulated blast furnace slag, and silica fume. SCMs, typically, have a lower carbon footprint compared to Portland cement. However, these SCMs may reduce the performance of concrete including concrete strength particularly at early curing time.

[0007] In some existing systems, the performance reduction of concrete is mitigated by the use of nanomaterials and more specifically carbon nanomaterials (CNMs)-containing cement and concrete admixtures. These nanomaterials are used to prepare the concrete with improved performance such as higher early and late strength, improved durability and added reinforcement to maintain the overall performance. Such carbon nanomaterials include 1-D carbon nanotubes (CNTs), 2-D graphene sheets, and 3-D graphene particles. Further, the graphene sheets and graphene particles can have a Bernal-stacked or Turbostratic arrangement of carbon layers. In existing systems, methods of dispersing graphene sheets and particles within the cement matrix result in non-uniform dispersion. In some existing systems, pre-dispersed graphene dispersions are used to facilitate uniformity of dispersion. Existing pre-dispersed dispersions, once adopted however, are prone to breaking down (i.e. not stable) prior to use similar to conventional concrete admixtures, for example, as an admixture during batching at a concrete plant.

[0008] Furthermore, rapidly growing construction projects create a demand for substantial amounts of Portland cement that contributes significantly to carbon dioxide emissions. There is an urgent desire to develop carbon-neutral concrete, and many nations are moving towards carbon neutrality and reducing their CO2footprint. This is possible by using less Portland Cement, such as incorporating materials that allow partial replacement of cement without compromising the overall concrete strength. However, existing admixture methods and compositions are insufficient and unstable to meet this demand.

[0009] In some existing systems, a wet method is used to mix admixtures with concrete mixture. The admixture is mixed with sand, large aggregates, cement, and water in different mixing containers such as tanks or concrete trucks. For cement slurries, plain cement is used. The mixing procedure and duration will depend on the type of admixtures and concrete mixture. The wet process may improve the interaction of admixtures with cement particles, yielding a change in surface chemistry interaction that would impact the properties of the concrete.

[0010] In other existing systems, a dry method could be used to introduce additives during the cement production process in an “inter-grinding” process. The additives are first mixed with clinker, gypsum, and limestone added to the ball milling process that prepares cement. The dry method may be more difficult to implement compared to the wet method due to the feeding operations used to disperse the additive phase in the cement mixture.

[0011] In some existing systems, SCMs can be used as partial replacement to Portland cement or blended with Portland cement. Patent US20070095255A1 describes the production of cement containing slag as a replacement which also acts as a pozzolanic material. The slag recommended to be used can be alloy steel slag or steel slag. In another patent application, US7410537B2, an improved process to produce slag-containing Portland cement has been described. The slag used in the process was ground granulated blast furnace slag (GGBFS). A ternary blend of cement obtained by mixing two SCMs with Portland cement for low-density cementing application has been described in patent application US20100294496A1. The method describes the cementitious binder comprising metakaolin (MK) in an amount greater than 5% and silica fume (SF) in an amount up to 15% by weight of the total binder. However, the use of SCMs undesirably leads to slower strength development, thereby impacting the early-age strength properties. For example, pozzolanic materials may be cheaper than Portland Cement, but their use as blends or replacements may lead to slower strength development.

[0012] In some existing systems, nanomaterials based on metallic oxides such as titania (TiO2), alumina (AI2O3), iron oxide (Fe2O3), zinc oxide (ZnO) and Zirconia (ZrO2) have been used. These nanomaterials provide specific desired properties, improve the pore properties of concrete, and in some cases, boost the formation of cement hydration products. The patent application US6653356B2 explains the use of nanoparticulate titanium dioxide (TiO2) coatings with photocatalytic activity for concrete. Another patent application describes the use of zinc oxide nanoparticles with photocatalytic activity for construction materials. US20140251186A1 explains the use of zinc oxide greater than 2.5% in fly ash-containing concrete that is easy to handle and highly corrosion resistant. The patent application number WO2021154314A1 describes the method to prepare a cementing composition based on nanosized alumina (AI2O3) as a cement accelerator and compressive strength enhancer. In some of the other existing systems, oxides based on silicon can be used to improve the mechanical performance and durability of concrete. These may include nano silica, colloidal silica, and silica fume, used in the optimal concentrations. The patent application number EP 3094460A1 explains the method for adding colloidal silica as an admixture to concrete. However, these materials are expensive and undesirably impact the workability of concrete.

[0013] In some of the existing systems, strength-enhancing additives such as higher alkanolamines can also be used. The patent US0055084103A describes a process for admixing or inter-grinding a higher alkanolamine with Portland cement to achieve higher compressive strength. The Portland cement in such case needs to have at least 4% tetracalcium aluminoferrite (C4AF). Such amines undesirably alter the air content of the cement matrix.

[0014] In some existing systems, more than one strength-enhancing additive can be added to the hydraulic cementitious material to achieve a synergistic effect. The patent applicationUS 2018 / 0312435A1 describes a method comprising the addition of two strength-enhancing additives, one being a higher alkanolamine and other being an inorganic salt of sodium.

[0015] In some existing systems, co-accelerators devoid of chlorides and nitrites can be used. The use of co-accelerators based on nitrate or sulfate, thiocyanate, alkanolamine and carboxylic acid for cement and cement mixtures has been described in US5605571A.

[0016] In further existing systems, carbon nanomaterials can be used to reinforce the CMs. These include one-dimensional carbon nanotubes (CNTs) and carbon nanofibers (CNFs) as described in patent US2021 / 0355041 A1 as well as other graphite-based nanomaterials such as graphene sheets, graphene particles, and carbon black. The CNTs and CNFs provide excellent thermal and mechanical properties, inhibit crack propagation, and act as crack-bridging structures in the cement matrix. Graphene or graphene derivatives provide the template effect for the cement hydration products for their growth.

[0017] The insufficient synergy and high cost or lack of adequate dispersion of the materials in these existing systems mitigates the benefit they provide.

[0018] Different forms of graphene-based modifiers such as graphene oxide (GO), reduced graphene oxide (RGO), pristine graphene, and functionalized graphene have been investigated in cement and concrete. Most employed graphene-based modifiers are based on graphene oxide (GO) chemistry. The extensive presence of oxygen functional groups in GO such as hydroxyl (-OH), epoxide (-O-), carboxyl (-COOH), and ketone carbonyls (-COO) improves the dispersion of graphene in water. In addition, the exceptional elastic modulus and tensile behavior of GO make it an excellent reinforcing carbon nanomaterial for cementitious materials and concrete. It has been shown that GO can govern the growth and pattern of hydration crystals in cement owing to its “template effect”. Thus, incorporating GO as nano-reinforcement is promising to enhance the overall performance of concrete such as higher mechanical strength, improved toughness, better durability, reduced porosity, and higher resistance to chemical and acidic attack. However, the existing methods for the synthesis of GO are based on harsh chemicals and long reaction times. Additionally, high pH conditions of cementitious systems may lead to GO agglomerations, causing them to sediment out during concrete preparation.

[0019] Reduced graphene oxide and pristine graphene are hydrophobic and less water- dispersible compared to GO based dispersion. Existing dispersing agents and tools can improve their dispersion and enhance their reinforcing behavior within the cementitious materials. However, the lack of details about these existing dispersing agents’ properties, agglomerates of graphene sheets and a poor interaction between graphene and the matrix still can mitigate dispersal uniformity.

[0020] In some existing systems, graphene or graphene derivatives used as reinforcing material in concrete are obtained through physical or chemical processing of graphite or graphite oxide. The physical method includes peeling, grinding, milling graphite, and sonicating graphite in suitable solvents. The chemical process normally involves the chemical oxidation / intercalation of graphite, exfoliation of graphite oxide by sonication, and chemical reduction of exfoliated graphene oxide into reduced graphene oxide. The exfoliation and reduction in the chemical approach can also be done by a rapid heating process using microwaves, furnaces, hot baths, and lasers. Other graphene preparation methods include chemical / physical vapor deposition, carbon nanotube opening, etc. Graphene obtained using these methods has a two-dimensional (2D) sheet-like morphology with a range of lateral size and thickness that can be used to define its aspect ratio. Generally, graphene fabricated by these methods has layers that are Bernal stacked (all graphene produced from graphite), predominantly has 15 layers up to > 30 layers of graphene stacked, has low 2D / G ratios < 0.3, and has carbon contents from 90 to 95%. The Bernal stacking between the graphene layers of the existing graphene impedes the exfoliation of the layers. Furthermore, the large number of layers results in the inner layers contributing to the matrix mass but not being bound to the matrix and therefore do not contribute to the performance of the matrix. In addition to the loss of performance, increasing the concentration of existing graphene in a cementitious matrix to achieve high-performing concrete is more challenging and less cost-effective.

[0021] Accordingly, there is a need for compositions, for cement and concrete modifiers and systems and methods for manufacturing the same that overcome the difficulties described above.Summary

[0022] A graphene-based cement modifier is provided. The graphene-based cement modifier includes graphene obtained via a flash joule heating process applied to a carbon source.

[0023] In an embodiment, the graphene-based modifier is formulated for modifying concrete including cement.

[0024] In an embodiment, the graphene-based modifier may include additional functionalizing additives.

[0025] In an embodiment, the graphene serves as an additive, modifier, or performance promoter.

[0026] In an embodiment, the modifier further includes a functionalizing additive.

[0027] In an embodiment, the additional functionalizing additives serve as the dispersing and compatibilization promoters.

[0028] In an embodiment, the modifier may be added as an admixture directly to the concrete mix during batching.

[0029] In an embodiment, the modifier may be batched in the concrete mix.

[0030] In an embodiment, the batching may be via a high-speed mixer.

[0031] In an embodiment, the surface functionality of the graphene may be modified by one or more of a flash process, a post-process, a post-treatment, a surfactant, a dispersant, an organic or inorganic ligand, and a coupling agent.

[0032] In an embodiment, a graphene-based dispersion include the dispersing agents.

[0033] In an embodiment, the dispersing agents include superplasticizers such as polycarboxylate ethers, organic solvents such as amine-based compounds, organic acids such as carboxylic acids, and concrete accelerators such as metallic salts.

[0034] In an embodiment, the cement includes hydraulic cement.

[0035] In an embodiment, the hydraulic cement includes Portland Cement.

[0036] In an embodiment, the Portland Cement may be Type I, Type II, Type III, Type IV,Type V; and limestone blended Portland cement.

[0037] In an embodiment, the concrete may include Portland cement or a blend of Portland cement and Supplementary Cementitious Materials (SCMs).

[0038] In an embodiment, the SCMS may include fly ash, ground-granulated blast furnace slag, metakaolin, and biochar.

[0039] In an embodiment, the graphene may be a turbostratic flake graphene.

[0040] In an embodiment, the turbostratic flake graphene is made from a natural material, for example, coke or coal; or from a processed material, for example, petroleum-based coke, processed biomass, etc.

[0041] In an embodiment, the graphene may be a polyhedral graphene.

[0042] In an embodiment, the polyhedral graphene may be made from a carbon black.

[0043] In an embodiment, the turbostratic flake graphene and polyhedral graphene may be made from recycled materials, such as recycled rubbers, tire rubbers, or plastics.

[0044] In an embodiment, the turbostratic flake graphene and polyhedral graphene may be made from biomass wastes or low-cost feedstocks.

[0045] In an embodiment, the turbostratic fiber graphene may be made from biomass wastes or low-cost fibrous feedstocks.

[0046] In an embodiment, the graphene-based cement modifier may be added directly to cement and / or concrete mixture to improve its mechanical performance and durability performance.

[0047] In an embodiment, the addition of the modifier may be at low concentration.

[0048] In an embodiment, the mechanical performance may be compressive strength, flexural strength, accelerated curing.

[0049] In an embodiment, the durability performance may include a longer service life with improved mechanical durability, increased density, reduced water permeability, reduced shrinkage, improved stability to oxidation, improved resistance to chloride permeability.

[0050] In an embodiment, the graphene may be modified to have surface functionalities different from pristine graphene.

[0051] In an embodiment, the modified graphene has an improved affinity of graphene and cement particles, and results in better dispersion and stability, and enhanced hydration and nucleation performance.

[0052] In an embodiment, the modification may be controlled by the flash process.

[0053] In an embodiment, the flash process can be a control of defects density, flash with a chemical or chemicals to create selective dopants, or flash in a gas or gases to create selective dopants.

[0054] In an embodiment, the modification may be a post-process or post-treatment.

[0055] In an embodiment, the post-process or post-treatment may include a mechanical mill or chemical functionalization, or plasma etching.

[0056] In an embodiment, the graphene-based cement modifier may be blended in cement and / or concrete using a typical wet mixing tool.

[0057] In an embodiment, the mixing tool may include a rod or stick stirrer, overhead stirrer, impeller agitator, vortex mixer, rotary drum mixer, high shear mixer, static mixer, planetary mixer, concrete truck mixer such as those commonly used in the concrete industry, or similar.

[0058] In an embodiment, the graphene-based cement modifier may be formulated into a liquid admixture at low concentrations or as a master batch to make a graphene-based cement modifier that can be used as an additive to cement and / or concrete to improve mechanical and durability performance.

[0059] In an embodiment, the dispersants may be used in the graphene-based cement modifier that can improve the graphene dispersion within the modifier and in the cementitious matrix.

[0060] In an embodiment, the dispersants may include polymers or superplasticizers such as lignosulfonates, sulfonated polymers, polycarboxylate ethers, ethoxylated polymers, or a blend of these superplasticizers.

[0061] In an embodiment, the superplasticizers may provide ionic interactions (electrostatic repulsions) or steric effects to achieve well-dispersed cement particle suspensions.

[0062] In an embodiment, an alkanolamine may be used as a component in the graphenebased cement modifier.

[0063] In an embodiment, the alkanolamine component may include a salt of an organic or inorganic acid, or a mixture thereof.

[0064] In an embodiment, the alkanolamine may include monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), triisopropanolamine (TIPA), diethanolisopropanolamine (DEIPA), ethyldiisopropanolamine (EDIPA), N,N-bis(2-hydroxyethyl)- N-(2-hydroxypropyl)amine (BHEHPA), tri(2- hydroxybutyl)amine (T2BA), N,N,N’,N’-tetrakis-(2- hydroxyethyl)-ethylenediamine (THEED), or a mixture of two or more alkanolamines.

[0065] In an embodiment, a carboxylic acid may be used as a component in the graphenebased cement modifier.

[0066] In an embodiment, the carboxylic acid may be selected from the group consisting of an alpha-hydroxy monocarboxylic acid; an alpha-amino carboxylic acid; an alkali, alkaline earth metal, or ammonium-salt of an alpha-hydroxy monocarboxylic acid; an alkali, alkaline earth metal, or ammonium-salt of an alpha-amino carboxylic acid; a C1 -C4 -alkyl ester of an alpha-hydroxy monocarboxylic acid; a C1 -C4 -alkyl ester of an alpha-amino carboxylic acid; and mixtures thereof.

[0067] In an embodiment, the carboxylic acid may be from the group of hydroxycarboxylic acids and can include glycolic acid (GA), oxalic acid (OA), maleic acid (MA), citric acid (CA), lactic acid (LA), acrylic acid (AA), ethylenediaminetetraacetic acid (EDTA), or a mixture of two or more acids.

[0068] In an embodiment, an accelerator may be used as a component in the graphenebased cement modifier.

[0069] In an embodiment, the accelerator may be based on alkali or alkaline earth metal inorganic salts, or a mixture thereof.

[0070] In an embodiment, the inorganic salts may include calcium chloride (CaCh), calcium nitrate (Ca(NO3)2), calcium nitrite (Ca(NO2)2), sodium nitrate (NaNO3), sodium nitrite (NaNCL), sodium thiocyanate (NaSCN), calcium thiocyanate (Ca(SCN)2), a blend of two or more inorganic salts.

[0071] In an embodiment, the Air - detrainers may be used as a component in the graphene-based cement modifier.

[0072] In an embodiment, the air detraining agents may include non-ionic surfactants such as phosphates that may include dibutylphosphate (DBP) and tributylphosphate (TBP), phthalates that may include dibutylphthalate (DBPh) and diisodecylphthalate (DIDPh), block copolymers that may further include polyoxypropylene-polyoxyethylene-block copolymers (POP- POE), and the like, or a mixture thereof.

[0073] In an embodiment, the modification may include achieved by a surfactant, dispersant, organic or inorganic ligand, coupling agent, viscosity-modifiers, water, other chemical admixtures such as water reducers, mid-range waters and high-range water reducers (examples of water reducers are lignosulfonic acids, salts of lignosulfonic acids, hydroxylated carboxylated acids, polysaccharides, melamine condensation products, naphthalene condensation products and polycarboxylates), accelerators (examples are calcium chloride, sodium formate, calcium formate, calcium nitrate, calcium aluminate, calcium silicate, triethanolamine, sodium thiocyanate, etc.), air-entrainers (examples are synthetic detergents, salts of sulfonated lignin, salts of petroleum acids, gum rosin salts, fatty and resinous acids, alkylbenezene sulfonates), corrosioninhibitors (examples are amine carboxylates, aminoesters, calcium nitrite, chromates, phosphates, hypophosphites, alkalies, fluorides), colorants (examples are carbon black, iron oxide, phthalocyanine, chromium oxide, titanium dioxide), viscosity-modifiers (examples are polyethylene oxides, cellulose ethers, alginates, polysaccharides, polyacrylamides, polyvinyl alcohol), and air-detrainers (examples are polypropylene glycols, octyl alcohol, polydimethylsiloxane, water-soluble esters of carbonic and boric acids), etc.

[0074] In an embodiment, the graphene-based cement modifier may be added into cement and / or concrete as a liquid admixture directly in the concrete plant using a typical mixing tool.

[0075] In an embodiment, the mixing tool may include a rod or stick stirrer, overhead stirrer, impeller agitator, vortex mixer, rotary drum mixer, high shear mixer, static mixer, planetary mixer, concrete truck mixer such as those commonly used in the concrete industry or similar.

[0076] In an embodiment, the graphene-based cement modifier is added into cement and / or concrete to improve its mechanical performance and durability performance.

[0077] In an embodiment, the graphene-based cement modifier may be added into cement as a powder (non-dispersed) or pre-dispersed form by dry mixing directly to cement milling operation in a cement plant via a water mist feeder, grinding aid feeder, etc.

[0078] In an embodiment, the graphene-based cement modifier that was blended in cement may be added into paste, and / or mortar, and / or concrete to improve mechanical performance and durability performance.

[0079] In an embodiment, the mechanical performance may include compressive strength, flexural strength, and accelerated curing.

[0080] In an embodiment, the durability performance may include a longer service life with improved mechanical durability, increased density, reduced water permeability, reduced shrinkage, improved stability to oxidation, and improved resistance to chloride permeability.

[0081] A graphene-based modifier modified cement is provided. The modified cement includes a graphene-based cement modifier including graphene obtained via a flash joule heating process applied to a carbon source; and a cement.

[0082] In an embodiment, the modifier is formulated for modifying concrete.

[0083] In an embodiment, the graphene is at least one of: an additive; a modifier; and a performance promoter.

[0084] In an embodiment, the modifier further comprises a functionalizing additive.

[0085] In an embodiment, the functionalizing additive is at least one of: a dispersing promoter; and a compatibilization promoter.

[0086] In an embodiment, the cement is added as an admixture to a concrete mix during batching.

[0087] In an embodiment, the surface functionality of the graphene may be modified by at least one of: a flash process; a post-process; a post-treatment; a surfactant; a dispersant; an organic or inorganic ligand; and a coupling agent.

[0088] In an embodiment, the cement includes a hydraulic cement.

[0089] In an embodiment, the hydraulic cement is a Portland cement.

[0090] In an embodiment, the graphene is at least one of: turbostratic flake graphene; and polyhedral graphene.

[0091] In an embodiment, the turbostratic flake graphene is made from at least one of a natural material; and a processed material.

[0092] In an embodiment, the polyhedral graphene is made from a carbon black.

[0093] In an embodiment, the graphene is modified to have surface functionalities different from pristine graphene.

[0094] In an embodiment, the modifier further includes at least one of: an alkanoamine; a carboxylic acid; an accelerator; an air detrainer; an air entrainer; a surfactant; a dispersant; an organic ligand; an inorganic ligand; a coupling agent; a viscosity-modifier; water; a water reducer; a mid-range water reducer; a high-range water reducer; a corrosion-inhibitor; and a colorant.

[0095] In an embodiment, the modified cement is added to one of: paste; mortar; and concrete, to improve mechanical performance and durability performance.

[0096] A method of producing a graphene-based modifier modified cement is provided. The method includes providing the graphene-based modifier, wherein the graphene-based modifier includes graphene obtained via a flash joule heating process applied to a carbon source; and combining the graphene-based modifier with a cementitious material.

[0097] In an embodiment, combining the graphene-based modifier with a cementitious material includes wet mixing the graphene-based modifier into a cement-containing matrix.

[0098] In an embodiment, the wet mixing is by at least one of: rod stirrer; stick stirrer; overhead stirrer; impeller agitator; vortex mixer; rotary drum mixer; high shear mixer; static mixer; planetary mixer; and concrete truck mixer.

[0099] In an embodiment, the cement-containing matrix is at least one of: cement paste; cement mortar; and concrete.

[0100] In an embodiment, the graphene includes surface functionalities including at least one of: O-based doping; N-based doping; islands; domains; and heterogeneous structures to act as active sites for interfacial bonding with the cement-containing matrix.

[0101] In an embodiment, the graphene is combined with a carrier to facilitate the dispersion in the cement-containing matrix.

[0102] In an embodiment, the graphene is at least one of: in a bead form; and in a fine powder form.

[0103] In an embodiment, the graphene is pre-mixed with dispersing agents before being admixed with the cement-containing matrix.

[0104] In an embodiment, combining the graphene-based modifier with a cementitious material includes: inter-grinding the graphene-based modifier with cement raw materials to obtain modified raw materials; sintering the modified raw materials to obtain clinker; and milling the clinker to obtain modified cement powder.

[0105] The method of claim 79, wherein combining the graphene-based modifier with a cementitious material further includes mixing an additive into the cementitious material, the additive including at least one of: water; other chemical admixtures; water reducers, mid-rangewaters; high-range waters; accelerators; air-entrainers; corrosion-inhibitors; colorants; viscositymodifiers; and air-detrainers.

[0106] Other aspects and features will become apparent to those ordinarily skilled in the art, upon review of the following description of some exemplary embodiments.Brief Description of the Drawings:

[0107] The drawings included herewith are intended to illustrate various examples of articles, methods, and apparatuses described in the present specification. In the drawings:

[0108] Figure 1 is a block diagram of concrete and mortar comprising a graphene-based modifier, according to an embodiment;

[0109] Figure 2 is a block diagram of processing TG of Figure 1 into various graphene powders, according to an embodiment;

[0110] Figure 3 is a plot of particle size analysis of a graphene-based cement modifier under higher temperature conditions, according to an embodiment;

[0111] Figure 4 is plot of storage modulus and loss modulus data against angular frequency, according to an embodiment;

[0112] Figure 5 is a plot of amplitude sweep results of a graphene-based cement modifier, according to an embodiment;

[0113] Figure 6 is a flow diagram of the production of the graphene-based modifier modified cement and concrete of Figure 1 , according to an embodiment;

[0114] Figure 7 is a flow diagram of a framework to modify and test the cement and concrete of Figure 1 , according to an embodiment;

[0115] Figure 8 is an image showing the improved resistance of a graphene-based cement modifier to sulphate attack, according to an embodiment; and

[0116] Figure 9 is a chart showing the results of a structural characterization performed on hardened cement mortar fragments after 1 day of curing of the mortar of Figure 1 , according to an embodiment.Detailed Description

[0117] Various apparatuses or processes will be described below to provide an example of each claimed embodiment. No embodiment described below limits any claimed embodiment and any claimed embodiment may cover processes or apparatuses that differ from those described below. The claimed embodiments are not limited to apparatuses or processes havingall of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below.

[0118] While the above description provides examples of one or more compositions, apparatus, methods, or systems, it will be appreciated that other compositions, apparatus, methods, or systems may be within the scope of the claims as interpreted by one of skill in the art.

[0119] Provided herein are compositions for graphene-based cement modifiers, and graphene-based concrete liquid admixture modifiers and method of making these modifiers, within cement and concrete mixtures. The graphene of these modifiers is graphene produced via FJH. It will be appreciated that graphene produced via FJH, of any morphology produced, exhibits measurable and observable properties conducive to use in the modifiers.

[0120] Provided herein are also methods of making mortar, concrete, or concrete mixtures with including the modifier. Making the mixtures with the modifiers includes the preparation of a graphene-based cement modifier which is a liquid admixture containing FJH graphene dispersed in a mixture of chemicals at predetermined concentrations. The FJH graphene may be turbostratic. The mixture of chemicals may include an aqueous solvent, an organic solvent, inorganic or a mixture of these chemicals. This liquid admixture is carefully formulated to ensure that the graphene particles exist in a pre-dispersed and deagglomerated state. Adhering to the predetermined concentrations maximizes the performance of individual graphene particles while minimizing the risk of re-agglomeration driven, for example, by Van der Waals forces. For instance, incorporating the dispersing agents can mitigate the formation of graphene agglomerates. Maintaining a pre-dispersed state of graphene ensures that the nucleation and template effect of graphene is effective. The graphene is dispersed uniformly in a mixture of dispersing agents commonly employed in the construction industry. The dispersing agents beneficially facilitate easy and uniform distribution of graphene in the cementitious matrix and beneficially impart long-term stability to graphene suspended in a liquid medium.

[0121] Definitions:

[0122] The term “cement”, herein, refers to a binder or a chemical substance that sets, hardens, and adheres to other materials to bind them together, also known as gelling. It will be appreciated that the gelling of the cement may not be initiated unless if a sufficient quantity of the gelling agent is applied to the unreacted cement. The sufficiency of the gelling agent may be dependent on the composition of cement or gelling agent or the application of the gelling agent to the cement. Existing types of cement include normal or general-use Portland Cement, moderate sulfate-resistant Portland cement, high-early-strength cement, low heat hydration cement, and high-sulfate resistant cement. It will be appreciated that the cement referred to herein is cementitious and does not necessarily include bitumen, also known as asphalt cement. Existingcement types may be designated based on if the properties of the cement meet industrial specifications and requirements. Properties of the cement or concrete that are inspected to confirm the quality of cement include compressive strength, air-content, early age strength development, heat of hydration, setting time, particle size, and Blaine value. Cement can be hydraulic or non-hydraulic. Hydraulic cement sets and glues the ingredients together through a chemical reaction with water. An example of Hydraulic Cement is the Portland Cement. Non- hydraulic cement reacts for the setting with a gas such as carbon dioxide and can set directly in the air.

[0123] The term “Portland Cement” refers to cement produced from clinker containing four main mineral phases, namely, C3S (Alite), C2S (Belite), C3A (Tricalcium Aluminate) and C4AF (Tetrcalcium Aluminoferrite). Typical constituents of Portland cement are 61-67% Calcium oxide (CaO), 19-23% silicon dioxide (SiO2), 2.5-6% aluminum oxide (AI2O3), 0-6% ferric oxide (Fe2O3) and 1.5-4.5% sulfur oxide (SO3). Portland cement may be of different types depending on chemical properties and each type may exhibit different properties. Portland Cement types include Ordinary Portland Cement (Type I), Modified Cement (Type II), Rapid-Hardening Portland Cement (Type III), Low-heat Portland Cement (Type IV) and Sulphate-resistant Cement (Type V). Portland Cement used herein may be blended with Supplementary Cementitious Materials (SCMs) or Pozzolanic Materials. Some of the examples of SCMs may include Ground-Granulated Blast Furnace Slag (GGBFS), Silica Fume (SF), Metakaolin (MK), Coal Fly Ash (CFA), and Biochar (BC).

[0124] The term “clinker”, herein, refers to nodules of a sintered material used in the production of the cement binder. Clinkers may have a size of 0.2 - 1.0 inches and are produced when a mixture of limestone and aluminosilicates is heated to a high temperature. The calcium silicates determine the mechanical properties of cement, whereas the aluminates and aluminoferrites are important for liquid phase formation during the sintering of clinker.The term “Pozzolanic Material”, herein, refers to a siliceous or siliceous and aluminous material that possesses little or no cementitious properties, but in the presence of moisture reacts chemically with lime generated or liberated by hydrating Portland Cement to produce compounds possessing cementitious properties.

[0125] The term “cementitious materials”, herein, refers to materials that contribute to the strength of concrete. The contribution may be by chemical or physical mechanisms. Examples cementitious materials include Portland cement and SCMs. The term cementitious materials may be referred to as “cement” or “cement matrix” or “cementitious matrix”.

[0126] The term “Supplementary Cementitious Materials” (SCMs), herein, refers to the materials that may be blended with Portland Cement. SCMs include Ground-Granulated BlastFurnace Slag (GGBFS), Silica Fume (SF), Metakaolin (MK), Coal Fly Ash (CFA), and Bio Char (BC). Most of the SCMs can be pozzolanic materials.

[0127] The term “mortar”, herein, refers to a mixture of cement, sand, and water. Mortar may be a paste that hardens or cures. Mortar may be used to bind building blocks such as stones, bricks, and concrete masonry units, and to fill and seal gaps between such blocks. These gaps may be irregular. Mortar may be referred to herein as “cement mortar”.

[0128] The term “concrete”, herein, refers to a composite material made up of cement, sand, aggregates, and water. Concrete is used extensively in the construction of buildings, towers, dams and bridges. The cement binder present in concrete hydrates or cures when mixed with water. Curing, also known as gelling, further binds the components of the concrete together to create a robust material.

[0129] The term “aggregate”, herein, refers to inert granular materials such as sand and stone. Aggregates typically account for 60 to 75 percent of the total volume of concrete. In existing concretes, aggregates are fine or coarse. Fine aggregates include standard sand, natural sand or crushed stone with most particles passing through a 3 / 8-inch sieve. Coarse aggregates are inert particles ranging between 3 / 8 and 1.5 inches in diameter.

[0130] The term “admixture”, herein, refers to the chemicals added to concrete to achieve a desired effect on the concrete properties. In existing systems, admixtures are added to concrete during the mixing stage with water and aggregates. In some existing systems admixtures comprise less than 5% by mass of the cement, within the concrete.

[0131] The term “graphene-based cement modifier” refers to an admixture that includes graphene. Other terms such as “graphene modifier” or “cement modifier” or “mortar modifier” or “concrete modifier” may also be used in place of graphene-based cement modifier.

[0132] The term “graphene” refers to any carbon-based structure comprising graphitic structural units present in various forms and morphologies. Existing forms and morphologies include 2D sheets, fiber-like structures, and polyhedral morphologies. The term “graphene” material that is a one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice. Graphene is the allotrope of carbon arranged in a layered honeycomb structure, referred to as a sheet. Graphene is the graphitic sheet present in the multilayer structure of graphite, up to 10 layers. Graphene contains an intact ring structure of carbon atoms and aromatic bonds throughout at least a majority of the interior sheet and lacks significant oxidation modification of the carbon atoms. Graphene has a predominantly crystalline structure, and its quality is measured by its degree of crystallinity. Graphene is distinguishable from graphene oxide in that it has a lower degree of oxygen-containing groups such as OH, COOH, and epoxide.

[0133] The term “graphene monolayer” refers to graphene, that is a single layer of graphene.

[0134] The term “very few-layer graphene” refers to a graphene that is between 1 to 3 layers of graphene.

[0135] The term “few-layer graphene” refers to graphene that is between 2 to 5 layers of graphene.

[0136] The term “multilayer graphene” refers to a graphene that is between 2 to 10 layers of graphene.

[0137] The term “Flash Joule Heating (FJH)” refers to the quick and intense heating of a resistive carbon source, as defined below, by passing an electric current through the resistive carbon source. Examples of flash joule heating are described in the “flash joule heating synthesis method and compositions thereof’ of Patent Cooperation Treaty Application having International Publication Number WO 2020 / 051000 A1 to Tour et al., having an international publication date of March 12, 2020, which is herein incorporated by reference in its entirety and “a system and methods for producing graphene by joule heating” described in Patent Cooperation Treaty Application having International Application Number WO2023044569A1 to Mancevski et al., having an international publication date of March 03, 2023, which is herein incorporated by reference in its entirety and “Device and method for continuous synthesis of graphene” described in Patent Cooperation Treaty Application having International Application Number W02021092705A1 to Mancevski publication date of May 20, 2021 , which is herein incorporated by reference in its entirety. FJH converts, via rapid graphitization, an amorphous carbon to a crystalline carbon made of a single to few layers of carbon atoms arranged in a hexagonal pattern. Turbostratic graphene is featured with a relative rotation angle between adjacent layers, which decouples the interlayer interaction and increases the interlayer spacing along the c-axis.

[0138] The term “carbon source”, herein, refers to any carbon-based material which is amorphous (non-crystalline) in whole or in part, which may be converted into a predominantly crystalline graphene material such as turbostratic graphene. The carbon source may be in any form, including in powder form, grain form, pellet form, or in compressed pill form. The carbon source may include, without limitation, coal, met coke, pet coke, carbon black, recycled plastics and rubber, biomass / biomass waste, and waste tire carbon black, petroleum coke, tire carbon black, carbon black, metallurgical coke, plastic ash, plastic powder, ground coffee, anthracite coal, coal, recycled plastic, recycled rubber, biomass, corn starch, pine bark, polyethylene microwax, wax, chemplex 690, cellulose, napthenic oil, asphaltenes, gilsonite, and carbon nanotubes.

[0139] The term “Turbostratic Graphene” (TG), herein, refers to a graphene that has little order between the graphene layers. This little order is distinct from existing graphene such as AB- stacked (Bernal) graphene. Each graphene layer of the turbostratic graphene structure is predominantly crystalline in nature. The little order may also be known as misoriented, twisted, rotated, rotationally faulted, and weakly coupled. The turbostratic nature of graphene may be observed and confirmed by Raman spectroscopy, Transmission Electron Microscopy (TEM), selected area electron diffraction (SAED), scanning transmission electron microscopy (STEM), atomic force microscopy (AFM), and X-ray diffraction (XRD) analysis. Predominant morphologies of TG that are produced as a result of a Joule heating process include flake-like turbostratic graphene structure (FTG), polyhedral-like turbostratic graphene structure (PG), and combinations thereof, further defined below.

[0140] The term “Polyhedral Graphene (PG)”, herein, refers to TG graphene with a polyhedral morphology. The PG may be prepared or synthesized by a Flash-Joule Heating process. Polyhedral Graphene may be prepared from different feedstocks such as carbon black, hydrocarbons, recycled tires, recycled plastics, etc. PG shows a unique three-dimensional (3D) branched structure compared to AB-stacked or turbostratic flake graphene. PG is a closed form of graphene that forms polyhedral cages, wherein multiple cages are nested within each other arranged like of an onion. Spherical cages are expressly contemplated. Typical PG graphene ranges from 10 nm to 300 nm in (diameter) size and has from 2 to more than 100 layers wall thickness. Polyhedral graphene nanoparticles can self-organize in a branched structure made from multiple PG nano sized primary particles, ranging in length from a few nm to a few microns.

[0141] The term “Flake-like graphene (FG)”, herein, refers to TG graphene with a flake morphology. FTG may be prepared by a Flash-Joule Heating process. In some embodiments, the FTG is processed to achieve a reasonable particle size, thickness, and exfoliation for an easy and stable dispersion in cement. Typical FTG graphene ranges from 100 nm to 2 pm in lateral size and from 2 graphene layers to more than 10 layers in thickness.

[0142] The term “Wet Mixing”, herein, refers to the introduction of graphene-based cement modifier to the cement and / or concrete mixtures within a liquid wherein the graphene is pre-dispersed in a formulated liquid.

[0143] The term “Dry Mixing”, herein, refers to the introduction of graphene-based cement modifier to the cement by an intergrinding process during the clinker milling operation in a cement plant. The modifier could be in powder form or pre-dispersed within a formulated liquid.

[0144] Graphene-Based Modifiers for Cement, Mortar and Concrete

[0145] Referring to Figure 1 , shown therein is a block diagram of concrete 102 and mortar 104 comprising a modifier 106 based on a synthesized material (e.g., a graphene-based modifier 106), according to an embodiment.

[0146] Portland cement, mortar 104, or concrete 102 may include graphene-based modifiers for improving the performance of the cement, mortar 104, and concrete 102. The modifier, when combined with the cement 114 and water 116 is known as cement slurry. Mortar includes the cement slurry 108 and sand 110. Concrete includes the mortar 104 and coarse aggregates 112.

[0147] Example graphene-based modifiers 106 include graphene produced using Flash Joule Heating (FJH). An example of the synthesized material is TG 118, which may be FG 120 and PG 122. These graphene-based modifiers, such as FG and PG modifiers, exhibit superior benefits compared to existing graphene-based cement modifiers. For example, flash joule heated graphene 118 provides the templating sites for the growth of cement hydration products. Specifically, when pre-dispersed in dispersing agents with surfactant properties, the joule-flashed graphene 118 may optimize the dispersion stability and improve its template effect due to induced-functionalization, without negatively impacting the concrete performance. This contributes to the synergistic improvement in modifier performance.

[0148] The rotational stacking of TG 118 helps mitigate interlayer coupling and increases interplanar spacing, thereby yielding superior physical properties relative to competitive graphene structures when compared on a similar weight basis. The subtle difference in adjacent layer stacking orientation expresses itself with important differences in product performance attributes. An important performance benefit evident with TG graphene 118 is that multi-layer graphene structures separate into few and individual graphene layers more easily, and the graphene layers tend not to recouple.

[0149] TG 118 provides various advantages over conventional graphene due to its turbostratic nature. For example, TG 118 is easier to delaminate and / or exfoliate compared to conventional graphene which can contribute to an improvement in preparing graphene dispersions. The relative rotation between adjacent layers may also alter the surface energy of TG 118, allowing it to interact with a media differently from AB-stacked graphene. Such an interaction can be better in certain cases to promote graphene wetting and dispersion in a media, solvent, or matrix. Such interaction may also improve the anchoring and functionalization by ligands, coupling agents, linkers, or chemicals to form functionalized graphene 124 or hybrid graphene 126 to improve the performance in the application.

[0150] The 3D branched structure of PG 122 promotes the 3-dimensional spatial interaction in the matrix when used in composite materials such as thermoplastics, thermosets, rubber as described in WO2022123499A1 and coating resins, cement, polyurethane foams asdescribed in WO2021077233A1 , and the like. The 3D spatial structure may also provide a tortuous or labyrinthine pathway. The tortuous pathway may slow down the diffusion of gas, vapour, salt, ions or other molecules or species. In a solid and / or liquid dispersion, the 3D branched morphology of PG 122 and its spatial interaction with a media can also alter the media’s viscosity, density, and rheology, and contribute to improvements in mechanical performance. Such a solid and / or liquid can be a cement 114, and / or concrete mixture 102.

[0151] Referring also to Figure 2, shown therein is a block diagram 200 of processing TG 118 into various graphene powders, according to an embodiment. The turbostratic flake graphene (FG) 120 may be processed 202 to achieve a reasonable particle size, thickness, agglomeration size, and exfoliation for easy and stable dispersion in cement. The process may be mechanical milling using a ball mill, rod mill, or via any milling method known in the art. Polyhedral graphene (PG) 122 may need a light process to deagglomerate to ease the dispersion of polyhedral graphene modifier into different media. The light process may be manually smearing, blade smearing, crushing, or any other process that deagglomerates graphene pellets into fine powders.

[0152] Moreover, the surface of graphene 118 may be modified (hybridized) 126, or functionalized 124 to improve its interfacial bonding with the cementitious matrix. The functionalization step 204 may be a mechanical milling, a wet chemical treatment, a solid chemical treatment, or a plasma treatment. In some embodiments, the graphene functionalization 204 may be a surface modification with a ligand, a resin, a dispersant, or a surfactant. The graphene may be functionalized 124 or modified (hybridized) 126, either using an in situ or ex-situ joule heating functionalization, or post-treatment, with a functional group. The functional groups may include, without limitation, oxygen, hydroxide, carbonyl, carboxylic acid, ketone, ether, unsaturated carbons, silane, chlorine, bromine, fluorine, or any combination thereof. The functional groups also include any heteroatom dopants, islands, and heterostructures that branch or attach to the surface of graphene or partially cover or replace graphene surfaces. The in-situ joule heating functionalization is related to creating a graphene surface functional group during the joule heating process, by controlling the joule heating condition and parameters, flash environment, atmosphere, or addition of chemicals. The parameters include, without limitations, the current, voltage, power, duration, flash batch size, flash device, and feedstock condition. The environment includes, but is not limited to, pressure, ventilation, and environmental temperature control / adjustment. The atmosphere may be any gas flow, ambient or pressurized gas blanket, inert or reactive gas, or gas mixture. The chemical may be one that may react with carbon at elevated temperatures to yield heteroatom dopants, islands, additional structures, and branches on the graphene surface. Examples of these chemicals include, without any limitation, sulfur, boron, boric acid, PTFE, SF6, melamine, etc. The post-treatment includes mechanical milling, wet chemistry, hydrothermal and thermal treatments, plasma reaction / oxidation, etc.

[0153] In some embodiments, the graphene-based cement and concrete modifier 106 is a graphene-containing liquid dispersion. The formulation process may be via any liquid mixing method known in the art. The method includes but is not limited to a blender, overhead mixer, low-shear mixer, high-shear mixer, three-roll mill, etc.

[0154] The graphene-based cement and concrete modifier 106 includes joule / resistive heating flashed graphene 118 with any morphology. The joule heating flashed graphene 118, and chemical additives 128 are formulated as the graphene-concrete liquid admixture. Flake turbostratic morphology 120 and polyhedral morphology 122, particularly polyhedral morphology 122, may provide improvements over other morphologies. The flake turbostratic graphene 120 or graphene with turbostratic flake morphology 120 may be of 1 - 500 nm in thickness and 1 to 200 pm in lateral size. The polyhedral graphene 122 is ensembled with turbostratic graphene polygons having walls and a hollow center or graphitized nucleus. The turbostratic graphene wall is at least 2 to 3 layers, up to several hundred layers. The overall diameter of polyhedral graphene is between 10 to 500 nm. The polyhedral graphene may be aggregated into secondary structures of 100 nm to 20 pm. The aggregates may be agglomerated into clusters of 200 nm to 200 pm. The agglomeration can be deagglomerated by means of shear, smear, milling, vibration, sonication, or any other methods known to the art. The graphene is used in the liquid admixture composite in an amount from 0.0001% to 20%, preferably from 0.0001% to 10%, and more preferably from 0.01% to 5%.

[0155] The graphene-based cement modifier 106 further comprises a chemical 128 or a mixture of chemicals 128 that are capable of functionalizing and dispersing the graphene, in addition to improving the fresh and / or hardened properties of cement or concrete.

[0156] Admixtures such as plasticizers, superplasticizers, accelerators, retarders, airentraining agents, air-detraining agents, corrosion inhibitors, and / or pigments are added during the concrete batching process to improve the performance and / or to achieve a desired property. Performance improvements depend substantially on the admixture selected, the dosage of the admixture, the compatibility of admixture with cement, and its incorporation method during the concrete batching.

[0157] The graphene-based cement modifier 106 may include chemicals 128 from the group of dispersing agents 130 that may comprise polycarboxylate ethers (PCE), lignosulfonates (LS), sulfonated naphthalene formaldehyde condensates (SNFC), ethoxylated polymers, etc. A combination of these dispersing agents 130 may also be used.

[0158] In addition, the graphene-based cement modifier may further include organic acids 132 that may functionalize the surface of graphene, facilitate the dispersion, and improve its template and nucleation effect within the cement matrix. Further, the acids may modify the early or late age hydration of cement. Exemplary organic acids include organic carboxylic acidsand may be from the group of hydroxycarboxylic acids and can include glycolic acid (GA), oxalic acid (OA), maleic acid (MA), citric acid (CA), lactic acid (LA), acrylic acid (AA), ethylenediaminetetraacetic acid (EDTA), etc. A mixture of two or more acids may also be used.

[0159] In addition, the graphene-based cement modifier may also include chelating compounds that may form stable ion complexes with undesired ions in the cement pore solution. The chelating compounds include organic solvents and may be from the group of alkanolamines 134. Exemplary alkanolamines may include monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), triisopropanolamine (TIPA), diethanolisopropanolamine (DEIPA), ethyldiisopropanolamine (EDIPA), N,N-bis(2-hydroxyethyl)-N-(2-hydroxypropyl)amine (BHEHPA), tri(2- hydroxybutyl)amine (T2BA). and N,N,N’,N’-tetrakis-(2-hydroxyethyl)- ethylenediamine (THEED), etc. A mixture of two or more alkanolamines 134 may also be used.

[0160] In addition, the graphene-based cement modifier may also include an accelerator 136 that may resolve the challenges associated with concrete making during cold-weather conditions. The accelerators may be from the group of alkali or alkaline earth metal inorganic salts, or a mixture thereof. Exemplary inorganic salts may include calcium chloride, calcium nitrate, calcium nitrite, sodium nitrate, sodium nitrite, sodium thiocyanate, etc. A blend of two or more inorganic salts may also be used.

[0161] In addition, the graphene-based cement modifier may also include an airdetraining agent that may regulate the excess air being generated from the other dispersing agents of the admixture. Suitable air detraining agents include but are not limited to, non-ionic surfactants such as phosphates that may include dibutylphosphate (DBP) and tributylphosphate (TBP), phthalates that may include dibutylphthalate (DBPh) and diisodecylphthalate (DIDPh), block copolymers that may include polyoxypropylene-polyoxyethylene-block copolymers (POP- POE), and the like, or a mixture thereof.

[0162] Dispersion Stability Behavior of Graphene-Based Cement Modifier

[0163] The graphene-based cement modifier is a thixotropic liquid which enables it to disperse easily in the mortar and concrete mixture, without impacting their rheology.

[0164] Referring now to Figure 3, shown therein is the particle size analysis 300 of the graphene-based cement modifier under higher temperature conditions (50°C), according to an embodiment. Figure 3 shows the long-term stability 302 of the graphene-based cement modifier for up to four months which is equivalent to one year stability at the room temperature. Similarly, the viscosity 304 of the graphene-based cement modifier also remains stable over a year.

[0165] The rheological behavior of graphene-based cement modifier also indicates its thixotropic behavior. Figure 4 is a plot 400 of the storage modulus 402 and loss modulus 404 data for the cement modifier. The loss modulus 404 represents the viscous (energy-dissipating)component, whereas the storage modulus 402 represents the elastic (energy-storing) component of the dispersion. At frequencies where the storage modulus 402 is greater than the loss modulus 404, there is more solid-like behavior and thus long-term stability. At higher frequencies, the loss modulus 404 is greater than the storage modulus 402, which indicates more liquid behavior - optimal for transport and dispensing systems.

[0166] The graphene-based cement modifier achieves and maintains stability at low frequencies (such as when stored on a shelf) for over 90 days at higher temperatures (for example, 50 C), which is equivalent to >12 months of stability at room temperature, while still maintaining liquid behavior and pumpability at higher frequencies.

[0167] Figure 5 shows the amplitude sweep results 500 of the graphene-based cement modifier, showing its linear viscoelastic region 502 and its yield behavior 504.

[0168] Preparation of Graphene-Based Cement and Concrete Modifiers

[0169] Referring to Figure 6, shown therein is a flow diagram 600 of a graphene-based modifier modified cement and concrete production, according to an embodiment.

[0170] Incorporation of Graphene-Based Cement and Concrete Modifiers

[0171] Wet Mixing:

[0172] In some embodiments, the graphene-based cement modifier 604 is blended into a base matrix such as cement paste, or mortar, or concrete. The incorporation or blending of graphene-based cement modifier 604 into concrete 616 may be done via a known “wet mixing” step 602, using any method that falls in the concept of agitation mixing. In an example wet mixing is by rod or stick stirrer, overhead stirrer, impeller agitator, vortex mixer, rotary drum mixer, high shear mixer, static mixer, planetary mixer, concrete truck mixer, and the like or a combination thereof. The base matrix is a cement-containing matrix that may include cement paste, cement mortar, and concrete. The cement paste may further include cement slurry for cementing applications that can comprise oil-field and non-oil-field cementing. According to some embodiments, the cementitious material comprises a Type I, IA, II, IIA, III, IIIA, IV or V Portland Cement, or a combination of or subtype thereof, such as, for example, Type IL, and Type IIIL (limestone-based cement powder), as defined in ASTM C150.

[0173] The joule heating flashed graphene 601 improves the dispersibility and stability of graphene-based cement modifiers in concrete, to yield a more uniform and stable fresh concrete mixture 616. The graphene-based cement modifiers 604 provide improved interaction with cement particles, increase cement particles' hydration, maintain the rheology properties of the concrete mixtures 616, and significantly improve their mechanical performance. The improved cement hydration properties may accelerate the C-S-H gel formation, leading to a denser crystalline structure with better early and late curing performance, as measured by the standardperformance testing described by the Canadian Standards Association (CSA) and American Society for Testing and Materials (ASTM) testing methods.

[0174] In some embodiments, the joule heating flashed graphene 601 may be further incorporated with surface functionalities, for example, with O-, N-based doping, islands, domains, and heterogeneous structures that may act as active sites for interfacial bonding with cement matrix.

[0175] In some embodiments, the joule heating flashed graphene 601 may be combined with a carrier to facilitate the dispersion in the cement matrix. The carrier may be in the form of colloidal silica, nano silica, micro silica, and silica fume.

[0176] In some embodiments, the joule heating flashed graphene 601 used in the graphene-based cement modifier may be in bead form or fine powders, preferably fine powders for ease of combination or dispersion with the cement matrix.

[0177] In some embodiments, graphene 601 may be pre-mixed with the dispersing agents before being admixed or intermixed with a cementitious matrix in the concrete batching mixer. Moreover, graphene may be first dispersed with a blend of dispersing agents or chemicals at high concentrations as a masterbatch and then used as an admixture during the concrete batching. The graphene-based cement modifier 604 in the “wet mixing” step may be used in cement and / or concrete in an amount of from 0.0001 - 50% by weight of the cement content (bwoc) in the base concrete mix design.

[0178] In some embodiments, joule heating flashed graphene 601 may be used directly as a graphene modifier to cement and / or concrete mixture, without pre-formulating into a liquid graphene-based cement modifier 604. The graphene modifier may improve interaction with cement particles, increase the degree of hydration of cement crystalline phases, maintain the rheological behaviour of the fresh concrete mixture, and improve its mechanical performance. The graphene-based cement modifier may be used in cement and / or concrete in an amount of from 0.0001% to 50% bwoc in the base concrete mix design.

[0179] Dry Mixing:

[0180] In some embodiments, cement powder including a flash graphene-based cement modifier is fabricated using the “dry mixing” 606 method. Dry mixing refers to inter-grinding 608 as part of the standard operation done at cement plants. The graphene-based cement modifier may be introduced as one material and / or pre-dispersed with additional materials / additives, and may be introduced via the dosing system to the clinker ball mill 610 to yield a uniform cement graphene mixture 612. The graphene-based cement modifier and / or additives can also be introduced with a standard nozzle system used to feed water and / or grinding aids to the cementmilling operation. The milling of cement with graphene modifier is done with standard operation conditions to a desired particle size and Blaine per cement specifications needed.

[0181] Additives:

[0182] Any additional cement and concrete additives may be added in the “wet mixing” or “dry mixing” process. For wet mixing, the additives can include, without limitation, water, other chemical admixtures such as water reducers, mid-range waters and high-range water reducers (examples of water reducers are lignosulfonic acids, salts of lignosulfonic acids, hydroxylated carboxylated acids, polysaccharides, melamine condensation products, naphthalene condensation products and polycarboxylates), accelerators (examples are calcium chloride, sodium formate, calcium formate, calcium nitrate, calcium aluminate, calcium silicate, triethanolamine, sodium thiocyanate, etc.), air-entrainers (examples are synthetic detergents, salts of sulfonated lignin, salts of petroleum acids, gum rosin salts, fatty and resinous acids, alkylbenezene sulfonates), corrosion-inhibitors (examples are amine carboxylates, aminoesters, calcium nitrite, chromates, phosphates, hypophosphites, alkalies, fluorides), colorants (examples are carbon black, iron oxide, phthalocyanine, chromium oxide, titanium dioxide), viscositymodifiers (examples are polyethylene oxides, cellulose ethers, alginates, polyacrylamides, polyvinyl alcohol), and air-detrainers (examples are polypropylene glycols, octyl alcohol, polydimethylsiloxane, water-soluble esters of carbonic and boric acids), etc.

[0183] The graphene-based cement modifier may be composed of 0-99% PG or FG, 0- 99% organic acids, 0-99% accelerators, 0-99% chelating compounds, 0-99% superplasticizer, 0- 99% and other additives such as air-detraining agents.

[0184] Performance Examples of Graphene-based Cement Modifier in Mortar and Concrete

[0185] Referring to Figure 7, shown therein is a flow diagram of a framework 700 to modify, test and validate the performance 702 of graphene-based cement modifier modified cement and concrete, according to an embodiment.

[0186] Mechanical Performance of Graphene-based Cement Modifier in Mortar 704a

[0187] The graphene- based cement modifier was added as a liquid admixture to a mortar mixture 704a. The mechanical mixing of cement mortars was done according to ASTM C305. The flowability of fresh mortars was tested according to ASTM C 1437. The air-content of freshly prepared cement mortars was determined according to ASTM C185. Compressive strength testing on cured cement mortar specimens was done according to ASTM C109. The standard sand used in mortar had the specifications outlined in ASTM C778. Some of the examples wherein graphene-based cement modifier was tested in mortar specimens are given below:

[0188] TG Graphene-Based Modifier in Type IL Cement Mortar

[0189] In this example, two mortar batches, namely control mortar without graphenebased cement modifier and mortar with graphene-based cement modifier, were prepared at w / c 0.485. The cementitious material used in this example was 100% Type IL Portland cement and the fine aggregates used were standard sand. For each batch, 50 mm cube specimens were prepared and tested for compressive strength as per ASTM C109 at different curing days. Graphene-based cement modifier was added to the mixer at the beginning of the batching process with the batching water. Referring to Table 1, the graphene-based cement modifier improved the compressive strength of the base mortar by 60% at early-curing time (1 day) and by 20% at late-curing time (28 days).

[0190] TABLE 1

[0191] TG Graphene-Based Modifier in Type IIIL Cement Mortar

[0192] In this example, the cementitious material used was 100% Type IIIL Portland cement. Other mortar batching conditions were similar to example 2. Type IIIL cement possesses higher strength compared to Type IL cement. Referring to Table 2, in this case, the graphenebased cement modifier improved the compressive strength by 28% at early curing time (1 day) and by 16% at late curing time (28 days).

[0193] TABLE 2

[0194] 7"G Graphene-Based Modifier in Type IL Cement Mortar with SCMS

[0195] In another example, the cementitious material used was a binary blend of 85% Type IL Portland cement and 15% of one of the supplementary cementitious materials (such as Slag). All the batching conditions were similar to examples 2 and 3, except that the water-to- cement (w / c) ratio was reduced to 0.45 per regional industrial specifications. Early age improvement was not noticed with the addition of graphene-based cement modifier, but significant strength improvements of 50% and 38% were seen at mid-curing time (7 days) and late curing time (28 days) as referred to in Table 3.

[0196] TABLE 3

[0197] TG Graphene-Based Modifier in Type IIIL Cement Mortar with SCMs

[0198] In another example, the cementitious material used was a ternary blend of 82% Type IIIL Portland cement, 10% Slag, and 8% Metakaolin at w / c 0.485. All the batching conditions were similar to Examples 2 and 3. Referring to Table 4, a significant enhancement in compressive strength ranging between 39% and 51% was observed at all the curing times with the addition of graphene-based cement modifier.

[0199] TABLE 4

[0200] 7"G Graphene-Based Modifier in Type IIIL Cement Mortar with SCMs, with 80%Cementitious Material (CM)

[0201] Based on the findings from examples 2, 3, 4 and 5, compressive strength was significantly enhanced in different mortar mix designs and indicated a potential to reduce the total cementitious content within the mortar mix. To conduct this validation, three mortar batches were prepared and tested - Control mortar with 100% CM, control mortar with 80% CM, and mortar with graphene-based cement modifier with 80% CM. The w / c was adjusted to maintain the required flowability in the mortar batches containing 80% CM. The original control mortar (100% CM) batch had a ternary blend of 82% Type IIIL Portland cement, 10% Slag, and 8% Metakaolin. Accordingly, the other two mortar batches were reduced for their CM content by 20%. Based on the findings from this example as referred to Table 5, it has been shown that graphene-based cement modifier can maintain the baseline compressive strength for mortars containing 80% CM.

[0202] TABLE 5

[0203] Mechanical performance of graphene-based cement modifier in Concrete 704b

[0204] The graphene-based cement modifier was added as a liquid admixture to a concrete mixture 704b. The modifier could be added as a late addition with the batching water, or as an early addition before the batching water. Concrete specimens were prepared according to ASTM C192 and compressive strength was tested according to ASTM C39. The slump and the air content of freshly prepared concrete were tested according to ASTM C143 and ASTM C231 respectively. Some of the examples wherein graphene-based cement modifier was tested in concrete specimens are given below:

[0205] TG graphene-based cement modifier in Type IIIL concrete with SCMs

[0206] In this example, two concrete batches namely control concrete without graphenebased cement modifier and concrete with graphene-based cement modifier were prepared at a concrete plant using a batching mixer at w / c 0.485. The cementitious material used was a ternary blend of 82% Type IIIL Portland cement, 10% Slag, and 8% Metakaolin. Natural sand was used as the fine aggregate, and 14 mm crushed stone was used as the coarse aggregate. Referring to Table 6, a significant improvement in strength was noticed at different curing times with the addition of a graphene-based cement modifier in concrete. The slump and the air content for both batches were in a similar range.

[0207] TABLE 6

[0208] TG graphene-based cement modifier in Type IIIL concrete with SCMs, with 80% Cementitious Materials (CM)

[0209] Based on the findings in example 6, it was worth exploring the performance of graphene-based cement modifier in concrete with 80% of the total cementitious materials (CM). In this example, two concrete batches namely control concrete with 100% CM without graphenebased cement modifier and concrete with 80% CM with graphene-based cement modifier were prepared at a concrete plant using a batching mixer at w / c 0.485. The 100% CM content was a ternary blend of 82% Type IIIL Portland cement, 10% Slag, and 8% MK. The 80% CM content was a ternary blend of 65.6% Type IIIL Portland cement, 8% Slag, and 6.4% MK. The total concrete volume was adjusted with additional aggregate content. It was shown from the findings as referred to in Table 7 that the modifier in 80% CM containing concrete helped to maintain a similar strength as the original 100% CM containing concrete. Each batch had a slump of 220 mm and an air content of 4.5%.

[0210] TABLE 7

[0211] 7"G graphene-based cement modifier in Type 11 IL Concrete for PrecastApplications

[0212] One of the dry precast applications of concrete is in Hollowcore (HC). Hollowcore is an extruded prestressed concrete slab with continuous voids to reduce weight and cost. It is primarily used as a floor and roof deck system. The process is typically economical, but any improvement of very early strength could allow faster striping time. Additionally, the need for faster striping time SCMs in this application, as known, SMCs will slow down the early-age strength performance of concrete. TG graphene-based cement modifier may allow the usage of SCM as a replacement in such cases while maintaining the original baseline strength.

[0213] In one such example, very early-age compressive strength was tested for the concrete with graphene-based cement modifier. Two concrete batches namely control concrete without graphene-based cement modifier and concrete with graphene-based cement modifier were prepared at a concrete plant using a batching mixer at w / c 0.365. The cementitious material used in the example was Type II IL. Referring to Table 8, it was shown that the compressive strength of the modifier-containing concrete was significantly boosted compared to the control concrete from 8 to 12.5 hours of curing.

[0214] TABLE 8

[0215] 7"G graphene-based cement modifier in Type 11 IL Concrete for PrecastApplications

[0216] Further to Example 3 above, it was also important to investigate how the performance of the graphene-based modifier would change by changing the order of addition to the mixer during the concrete batching.

[0217] In one of the examples, the modifier was introduced with dry materials to the mixer before the batch water. This means that the aggregates and cementitious materials were in dry phase when the graphene-based cement modifier was added to the concrete mixer, and the other mixing components were added afterward. Two concrete batches namely control concrete without graphene-based cement modifier and concrete with graphene-based cement modifier were prepared at a concrete plant using a batching mixer at w / c 0.365. As referred to in Table 9, early addition of the modifier in the concrete plant mixing procedure produced higher strength gains between curing time of 8-11 hours compared to late addition.

[0218] TABLE 9

[0219] TG graphene-based cement modifier in Type 11 IL Concrete with SCMs for Dry-CastApplications

[0220] Based on the findings in Example 4 above, the possibility of graphene-based cement modifier to allow 25% slag replacement in Type IIIL concrete was explored. Four concrete batches namely control concrete with 100% Type IIIL without graphene-based cement modifier, concrete with 100% Type IIIL with graphene-based cement modifier, control concrete with 75% Type IIIL and 25% Slag without graphene-based cement modifier, and concrete with 75% Type IIIL and 25% Slag with graphene-based cement modifier were prepared at a concrete plant using a batching mixer at w / c 0.365. Referring to Table 10, it was indicated that the strengths obtainedfor 75% Type IIIL and 25% Slag-based concrete with graphene-based cement modifier were close to the original baseline concrete with 100% Type IIIL. The strength obtained (20 MPa) was similar to the original mix design at 11 hours. There was about a 10% reduction in early-age strength (at 12.5 hours), which is acceptable for industrial applications.

[0221] TABLE 10

[0222] Durability Behavior of Graphene-based cement modifier in mortar and concrete 706

[0223] The graphene-based cement modifier was added as a liquid admixture to a mortar mixture or a concrete mixture. Some of the examples showing the improved durability performance 706 of mortar / con crete with graphene-based cement modifier are given below:

[0224] TG Graphene-based cement modifier in mortar for improved resistance to water absorption 706a

[0225] The relative water absorption 706a properties of cement mortars were determined over time as per ASTM C1403.

[0226] In this example, mortars were batched with a binary blend of 85% Type IL and15% Slag as the cementitious material (CM) at w / c 0.456. After 28 days of curing, the mortar specimens were removed and dried in a ventilated oven at 110°C for not less than 24 hours. The specimens were removed from the oven and allowed to cool to ambient conditions for 2 hours.Finally, the water absorption test was conducted for control mortar and mortar with graphenebased cement modifier. As referred to in Table 11, the water absorption recorded for mortar with graphene-based cement modifier was 38% lower than the control mortar over 3 days.

[0227] TABLE 11

[0228] Graphene-based cement modifier in mortar for improved resistance to sulphate attack 706bIn this example, mortars were batched with Type IL as the cementitious material (CM) at w / c 0.485. After 28 days of curing, the mortar specimens were removed and exposed to 18.5% sulfate solution for 1 month. Figure 8 is an image 800 which shows the formation of expansive crystals of ettringite 802 on the surface of the control mortar specimens 804 (top two cubes in the Figure 8), whereas no crystal formation took place in the specimen containing graphene-based cement modifier 806 (bottom two cubes in the Figure 8). These expansive crystals are produced due to the presence of a chemical reaction between the C3A phase of cement and the sulphate ions, leading to the formation of ettringite 802. Some amount of calcium sulphate in the form of gypsum is added to the cement on purpose which helps to control the faster reaction rate of C3A hydration. The gypsum reacts with C3A to produce a passive layer of ettringite 802 around the C3A, which prevents further reaction and controls the unnecessary growth of additional ettringite crystals 802. But the presence of external sulphate ions can trigger this reaction and the C3A phase continues to produce these undesired crystals.

[0229] Graphene-based cement modifier in concrete for improved resistance to chloride penetration 706cTypically, the resistance to rapid chloride permeability 706c is lower for the concrete containing less cement content than for the concrete based on 100% cement content. The RCPT of the concrete specimens were tested in accordance with ASTM C1202.In this example, two concrete batches were prepared, one control concrete and another with graphene-based cement modifier. The CM material in these concrete mixtures was Type IL cement. The control concrete batch had 100% CM content, whereas the concrete batch with graphene-based cement modifier had 15% less CM (therefore, a total of 85% CM content). The RCPT testing on concrete containing 15% less cement content at 28-days showed the total charge of 2264 Coulomb (C). In comparison, the RCP for the control concrete based with 100% cement was found to be 2513 C. These results show that the graphene-based cement modifier allows for 15% cement reduction without impacting the chloride ion penetration behavior of concrete.

[0230] Graphene-based cement modifier in concrete for improved resistance to linear shrinkage 706dIn this example, two concrete batches were prepared using the same mix design as the above example (i.e., one control concrete and another with graphene-based cement modifier). The CM material in these concrete mixtures was Type IL cement. The control concrete batch had 100% CM content, whereas the concrete batch with graphene-based cement modifier had 15% less CM (therefore, a total of 85% CM content). The linear shrinkage 706d tested at 28-days for the control concrete was observed to be 0.069%, and that of a lower cement content-based concrete with graphene-based cement modifier was observed to be 0.062%. This shows that the cement content can be reduced by 15% using the graphene-based cement modifier in a concrete mix without impacting the linear shrinkage.

[0231] Graphene-based cement modifier in concrete for improved resistance to freezethaw 706eIn this example, two concrete batches were prepared using 100% Type IL as the cementitious material - a control concrete and another with graphene-based cement modifier. The freeze-thaw resistance 706e of both concrete batches was tested per ASTM C666. It was observed that after completion of 150 cycles of freezing and thawing, both the concrete batches exhibited no cracking or surface scaling and performed well. Table 12 provides the average loss in mass (%) for both concrete batches.TABLE 12

[0232] Degree of Hydration in Mortar with Graphene-based cement modifier 708

[0233] Referring now to Figure 9, shown therein are results 900 a structural characterization performed on hardened cement mortar fragments after 1 day of curing, according to an embodiment. The structural characterization analyzed the hydration degree of cement mortars. TGA tests were conducted on the control mortar 902 and the mortar with graphenebased cement modifier 904 and the content of calcium hydroxide and non-evaporable water were calculated for the hydrated samples. The samples were prepared at w / c 0.52, and the cementitious material used was a ternary blend of 82% Type IIIL, 10% Slag, and 8% Metakaolin.

[0234] It was evident from the results mortar with graphene-based cement modifier showed higher percentages of hydration products. The loss in mass over the different decomposition dips was calculated and it was evident that C-S-H gel formation was 60% higher in mortar with graphene-based cement modifier 904 than control mortar 902. The mass of hydration products recorded over three main decomposition dips are referred to in Table 13.

[0235] TABLE 13

[0236] While the above description provides examples of one or more apparatus, methods, or systems, it will be appreciated that other apparatus, methods, or systems may be within the scope of the claims as interpreted by one of skill in the art. Elements of each embodiment may be incorporated into other embodiments, for example, additives discussed inrelation to one embodiment, may be applied to other embodiments disclosed herein. Further, it is evident that various modifications and combinations can be made without departing from the invention. The specification and drawings are, accordingly, to be regarded simply as an illustration of the invention as defined by the claims, and are contemplated to cover any and all modifications, variations, combinations or equivalents that fall within the scope of the present disclosure.

Claims

Claims:1 . A synthesized material-based cement modifier comprising: the synthesized material obtained via a flash joule heating process applied to a carbon source.

2. The modifier of claim 1 , wherein the modifier is formulated for modifying concrete including cement.

3. The modifier of claim 1 , wherein the synthesized material is at least one of: an additive; a modifier; and a performance promoter.

4. The modifier of claim 1 , further comprising a functionalizing additive.

5. The modifier to claim 4, wherein the functionalizing additive is at least one of: a dispersing promoter; and a compatibilization promoter.

6. The modifier of claim 1 , wherein the modifier is added as an admixture to a concrete mix during batching.

7. The modifier of claim 1 , wherein the modifier is batched in a concrete mix.

8. The modifier of any one of claims 6 or 7, wherein the batching is via a high speed mixer.

9. The modifier of claim 1 , wherein the surface functionality of the synthesized material may be modified by at least one of: a flash process; a post-process; a post-treatment; a surfactant; a dispersant; an organic or inorganic ligand; and a coupling agent.

10. The modifier of claim 1 , wherein a synthesized material-based dispersion includes a dispersant.

11. The modifier of claim 10, wherein the dispersant includes at least one of: a superplasticizer; an organic solvent; an organic acid; and a concrete accelerator.

12. The modifier of claim 2, wherein the cement includes a hydraulic cement.

13. The modifier of claim 12, wherein the hydraulic cement is a Portland cement.

14. The modifier to claim 13, wherein the Portland cement is at least one of: Type I; Type II; Type III; Type IV; Type V; and limestone blended Portland cement.

15. The modifier of claim 2, wherein the concrete includes at least one of: a Portland cement; and a blend of a Portland cement and a Supplementary Cementitious Materials (SCM).

16. The modifier to claim 15, wherein the SCM includes at least one of: fly ash; ground- granulated blast furnace slag; metakaolin; and biochar.

17. The modifier to claim 1 , wherein the synthesized material is at least one of: turbostratic flake graphene; and polyhedral graphene.

18. The modifier of claim 17, wherein the turbostratic flake graphene is made from at least one of a natural material; and a processed material.

19. The modifier of claim 17, wherein the polyhedral graphene is made from a carbon black.

20. The modifier of claim 17, wherein at least one of the turbostratic flake graphene and the polyhedral graphene is made from at least one of: recycled materials; recycled rubbers; tire rubbers; and plastics.

21. The modifier of claim 17, wherein at least one of the turbostratic flake graphene and the polyhedral graphene is made from at least one of: biomass wastes; low-cost feedstocks; and low-cost fibrous feedstocks.

22. The modifier of claim 1 , wherein the modifier is added directly to at least one of: cement; and concrete, to improve mechanical performance and durability performance.

23. The method of claim 2, wherein the addition of the modifier is at a low concentration.

24. The modifier of claim 22, wherein the mechanical performance includes at least one of: compressive strength; flexural strength; and accelerated curing.

25. The modifier of claim 22, wherein the durability performance includes at least one of: a longer service life with improved mechanical durability; an increased density; a reduced water permeability; a reduced shrinkage; an improved stability to oxidation; and an improved resistance to chloride permeability.

26. The modifier of claim 1 , wherein the synthesized material is modified to have surface functionalities different from pristine graphene.

27. The modifier of claim 26, wherein the modified synthesized material has at least one of: an improved affinity between the synthesized material and cement particles; an improved dispersion and stability; and an enhanced hydration and nucleation performance.

28. The modifier of claim 26, wherein the modification is controlled by the flash joule heating process.

29. The modifier of claim 28, wherein the flash joule heating process is at least one of: a control of defects density; a flash with at least one chemical to create a selective dopant; and a flash in at least one gas to create a selective dopant.

30. The modifier of claim 26, wherein the modification is a post-process or post- treatment.31 . The modifier of claim 30, wherein the post-process or post-treatment includes at least one of: a mechanical mill functionalization; a chemical functionalization; and a plasma etching.

32. The modifier of claim 1 , wherein the modifier is blended using a wet mixing tool in at least one of: cement; and concrete.

33. The modifier of claim 32, wherein the wet mixing tool includes at least one of: a rod stirrer; a stick stirrer; an overhead stirrer; an impeller agitator; a vortex mixer; a rotary drum mixer; a high shear mixer; a static mixer; a planetary mixer; and a concrete truck mixer.

34. The modifier of claim 1 , wherein the modifier is used as an additive to improve mechanical and durability performance by formulating the modifier into at least one of: a liquid admixture at low concentrations; and a master batch.

35. The modifier of claim 1 , further including a dispersant for improving the synthesized material dispersion within the modifier and in a cementitious matrix.

36. The modifier of claim 35, wherein the dispersant includes polymers or superplasticizers including at least one of: lignosulfonates; sulfonated polymers; polycarboxylate ethers; and ethoxylated polymers.

37. The modifier of claim 1 , further including an alkanolamine.

38. The modifier of claim 37, wherein the alkanolamine includes at least one of: a salt of an organic acid; and a salt of an inorganic acid.

39. The modifier of claim 37, wherein the alkanolamine includes at least one of: monoethanolamine (MEA); diethanolamine (DEA); triethanolamine (TEA), triisopropanolamine (TIPA); diethanolisopropanolamine (DEIPA); ethyldiisopropanolamine (EDIPA); N,N-bis(2-hydroxyethyl)-N-(2-hydroxypropyl)amine (BHEHPA); tri(2- hydroxybutyl)amine (T2BA); and N,N,N’,N’-tetrakis-(2-hydroxyethyl)- ethylenediamine (THEED).

40. The modifier of claim 1 , further including a carboxylic acid.41 . The modifier of claim 40, wherein the carboxylic acid is at least one of: an alpha-hydroxy monocarboxylic acid; an alpha-amino carboxylic acid; an alkali, alkaline earth metal, or ammonium-salt of an alpha-hydroxy monocarboxylic acid; an alkali, alkaline earth metal, or ammonium-salt of an alpha-amino carboxylic acid; a C1 -C4 -alkyl ester of an alphahydroxy monocarboxylic acid; and a C1 -C4 -alkyl ester of an alpha-amino carboxylic acid.

42. The modifier of claim 40, wherein the carboxylic acid is selected from a group of hydroxycarboxylic acids including at least one of: glycolic acid (GA); oxalic acid (OA); maleic acid (MA); citric acid (CA); lactic acid (LA); acrylic acid (AA); ethylenediaminetetraacetic acid (EDTA).

43. The modifier of claim 1 , further including an accelerator.

44. The modifier of claim 43, wherein the accelerator includes at least one of: an alkali; and an alkaline earth metal inorganic salts.

45. The modifier of claim 44, wherein the inorganic salts include at least one of: calcium chloride (CaCI2); calcium nitrate (Ca(NO3)2); calcium nitrite (Ca(NO2)2); sodium nitrate (NaNO3); sodium nitrite (NaNO2); sodium thiocyanate (NaSCN); calcium thiocyanate (Ca(SCN)2).

46. The modifier of claim 1 , further including an air detrainer.

47. The modifier of claim 46, wherein the air detrainer includes at least one of: a non-ionic surfactant; a phosphate; dibutylphosphate (DBP); tributylphosphate (TBP); a phthalate;dibutylphthalate (DBPh); diisodecylphthalate (DIDPh), a block copolymer, and polyoxypropylene-polyoxyethylene-block copolymers (POP-POE).

48. The modifier of claim 1 , further including at least one of: a surfactant; a dispersant; an organic ligand; an inorganic ligand; a coupling agent; a viscosity-modifier; water; a water reducer; a mid-range water reducer; a high-range water reducer; an accelerator; an airentrainer; a corrosion-inhibitor; a colorant; and an air-detrainer.

49. The modifier of claim 48, wherein the water reducer includes at least one of: lignosulfonic acids; salts of lignosulfonic acids; hydroxylated carboxylated acids; polysaccharides; melamine condensation products; naphthalene condensation products; and polycarboxylates.

50. The modifier of claim 48, wherein the accelerator includes at least one of: calcium chloride; sodium formate; calcium formate; calcium nitrate; calcium aluminate; calcium silicate; triethanolamine; and sodium thiocyanate.

51. The modifier of claim 48, wherein the air-entrainer includes at least one of: synthetic detergents; salts of sulfonated lignin; salts of petroleum acids; gum rosin salts; fatty and resinous acids; and alkylbenezene sulfonates.

52. The modifier of claim 48, wherein the corrosion-inhibitor includes at least one of: amine carboxylates; aminoesters; calcium nitrite; chromates; phosphates; hypophosphites; and alkalies, fluorides.

53. The modifier of claim 48, wherein the colorant includes at least one of: carbon black; iron oxide; phthalocyanine; chromium oxide; and titanium dioxide.

54. The modifier of claim 48, wherein the viscosity-modifier includes at least one of: polyethylene oxides; cellulose ethers; alginates; polysaccharides; polyacrylamides; and polyvinyl alcohol.

55. The modifier of claim 48, wherein the air-detrainer includes at least one of: polypropylene glycols; octyl alcohol; polydimethylsiloxane; water-soluble esters of carbonic acids; and water-soluble esters of boric acids.

56. The modifier of claim 1 , wherein the modifier is added using a mixing tool in at least one of: cement; and concrete.

57. The modifier of claim 56, wherein the mixing tool includes at least one of: a rod stirrer; a stick stirrer; an overhead stirrer; an impeller agitator; a vortex mixer; a rotary drum mixer; a high shear mixer; a static mixer; a planetary mixer; and a concrete truck mixer.

58. The modifier of claim 1 , wherein the modifier is added to cement in one of: a non-dispersed form; and a pre-dispersed form.

59. The modifier of claim 58, wherein the non-dispersed form includes a powder form.

60. The modifier of claim 58, wherein adding the modifier in the pre-dispersed form includes dry mixing the modifier directly to cement milling operation in a cement plant via at least one of: a water mist feeder; and a grinding aid feeder.61 . The modifier of claim 22, wherein the modified cement is added to one of: paste; mortar; and concrete, to improve mechanical performance and durability performance.

62. The modifier of claim 61 , wherein the mechanical performance includes at least one of: compressive strength; flexural strength; and accelerated curing.

63. The modifier of claim 61 , wherein the durability performance includes at least one of: a longer service life with improved mechanical durability; an increased density; a reduced water permeability; a reduced shrinkage; an improved stability to oxidation; and an improved resistance to chloride permeability.

64. A synthesized material-based modifier modified cement, comprising: a synthesized material-based cement modifier including synthesized material obtained via a flash joule heating process applied to a carbon source; and a cement.

65. The modified cement of claim 64, wherein the modifier is formulated for modifying concrete.

66. The modified cement of claim 64, wherein the synthesized material is at least one of: an additive; a modifier; and a performance promoter.

67. The modified cement of claim 64, wherein the modifier further comprises a functionalizing additive.

68. The modified cement of claim 64, wherein the functionalizing additive is at least one of: a dispersing promoter; and a compatibilization promoter.

69. The modified cement of claim 64, wherein the cement is added as an admixture to a concrete mix during batching.

70. The modified cement of claim 64, wherein the surface functionality of the synthesized material may be modified by at least one of: a flash process; a post-process; a posttreatment; a surfactant; a dispersant; an organic or inorganic ligand; and a coupling agent.71 . The modified cement of claim 64, wherein the cement includes a hydraulic cement.

72. The modified cement of claim 71 , wherein the hydraulic cement is a Portland cement.

73. The modified cement of claim 64, wherein the synthesized material is at least one of: turbostratic flake graphene; and polyhedral graphene.

74. The modified cement of claim 73, wherein the turbostratic flake graphene is made from at least one of a natural material; and a processed material.

75. The modified cement of claim 73, wherein the polyhedral graphene is made from a carbon black.

76. The modified cement of claim 73, wherein the synthesized material is modified to have surface functionalities different from pristine graphene.

77. The modified cement of claim 64, wherein the modifier further includes at least one of: an alkanoamine; a carboxylic acid; an accelerator; an air detrainer; an air entrainer; a surfactant; a dispersant; an organic ligand; an inorganic ligand; a coupling agent; a viscosity-modifier; water; a water reducer; a mid-range water reducer; a high-range water reducer; a corrosion-inhibitor; and a colorant.

78. The modified cement of claim 64, wherein the modified cement is added to one of: paste; mortar; and concrete, to improve mechanical performance and durability performance.

79. A method of producing a synthesized material-based modifier modified cement, the method comprising: providing the synthesized material-based modifier, wherein the synthesized materialbased modifier includes synthesized material obtained via a flash joule heating process applied to a carbon source; and combining the synthesized material-based modifier with a cementitious material.

80. The method of claim 79, wherein combining the synthesized material-based modifier with a cementitious material includes wet mixing the synthesized material-based modifier into a cement-containing matrix.

81. The method of claim 80, wherein the wet mixing is by at least one of: rod stirrer; stick stirrer; overhead stirrer; impeller agitator; vortex mixer; rotary drum mixer; high shear mixer; static mixer; planetary mixer; and concrete truck mixer.

82. The method of claim 80, wherein the cement-containing matrix is at least one of: cement paste; cement mortar; and concrete.

83. The method of claim 80, wherein the synthesized material includes surface functionalities including at least one of: O-based doping; N-based doping; islands; domains; and heterogeneous structures to act as active sites for interfacial bonding with the cementcontaining matrix.

84. The method of claim 80, wherein the synthesized material is combined with a carrier to facilitate the dispersion in the cement-containing matrix.

85. The method of claim 80, wherein the synthesized material is at least one of: in a bead form; and in a fine powder form.

86. The method of claim 80, wherein the synthesized material is pre-mixed with dispersing agents before being admixed with the cement-containing matrix.

87. The method of claim 79, wherein combining the synthesized material-based modifier with a cementitious material includes:inter-grinding the synthesized material-based modifier with cement raw materials to obtain modified raw materials; sintering the modified raw materials to obtain clinker; milling the clinker to obtain modified cement powder.

88. The method of claim 79, wherein combining the synthesized material-based modifier with a cementitious material further includes mixing an additive into the cementitious material, the additive including at least one of: water; other chemical admixtures; water reducers, mid-range waters; high-range waters; accelerators; air-entrainers; corrosion-inhibitors; colorants; viscosity-modifiers; and air-detrainers.

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