DESC:COMPOSITE MATERIAL
CROSS REFERENCE TO RELATED APPLICATIONS
The present application claims priority from Indian Provisional Patent Application No. 202421042719 filed on 01/06/2024, the entirety of which is incorporated herein by a reference.
TECHNICAL FIELD
Generally, the present disclosure relates to composite materials. Particularly, the present disclosure relates to composite materials for battery modules comprising electrical cells.
BACKGROUND
Composite materials have been widely used across various industries due to the favourable strength-to-weight ratio, design flexibility, and tunable mechanical, thermal, and chemical properties. In the context of battery modules, particularly those comprising high-energy-density electrical cells, the composite materials are increasingly being explored to replace traditional metals or rigid insulating enclosures. The composite materials provide structural support, thermal insulation, vibration damping, and enhanced safety.
Traditional approaches to battery module enclosure and support involve the use of metal casings, thermoplastics, or simple polyurethane foams or composite materials that provide adequate insulation or cushioning. Further, conventional composite materials are typically formed using a polymeric resin matrix reinforced with fibers, fillers, or other additives, and are processed through molding, lamination, or casting techniques, including calcium carbonate, talc, or silica. Specifically, the resin serves as the binding phase, providing cohesion and environmental resistance. The specific selection of matrix and filler depends on the target application and required performance metrics. For instance, thermosetting resins such as epoxy provide high chemical. The resulting composites are shaped using methods such as compression molding, resin transfer molding, pultrusion, or spray lay-up.
However, there are certain problems associated with the existing or above-mentioned composite materials. For instance, the conventional composite materials lack sufficient resistance to thermal propagation, mechanical shock, or chemical degradation that may arise during battery failure events such as thermal runaway or cell venting. Further, the metal-based enclosures tend to add significant weight and require additional electrical insulation layers to prevent short circuits. Furthermore, the rigid polymers or unmodified foams lack structural integrity under thermal or mechanical stress, which limits their utility in high-performance or safety-critical battery applications.
Therefore, there exists a need for a composite material capable of providing improved mechanical stability, thermal stability, and overcomes one or more problems as mentioned above.
SUMMARY
An object of the present disclosure is to provide composition for forming a composite material.
Another object of the present disclosure is to provide a composite material capable of providing improved mechanical stability and flame-retardant properties.
In accordance with an aspect of the present disclosure, there is provided a composition for forming a composite material, the composition comprising:
- a first compound comprising a polyether polyol in an amount of at least 35% weight of total weight of the composition and a triethanolamine in an amount of at least 2% weight of the total weight of the composition;
- a second compound comprising a modified poly-iso-cyanate in an amount of at least 30% weight of the total weight of the composition; and
- a flame retardant compound comprising an expandable graphite in an amount of at least 30% weight of the total weight of the composition.
The composition for forming a composite material, as described in the present disclosure, is advantageous in terms of providing a flame-retardant composite material by incorporating a flame retardant compound comprising expandable graphite, thereby ensuring early activation and formation of a protective char layer upon exposure to elevated temperatures. The expandable graphite provides a non-halogenated, thermally expandable mechanism that expands volumetrically to form an insulating barrier, effectively inhibiting heat transfer, reducing oxygen access, and suppressing flame propagation within and around the composite material. Further, the flame retardant composition contributes to low smoke generation and non-toxic byproduct formation, making the material particularly suitable for safety-critical applications such as battery modules in electric vehicles and energy storage systems.
It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims.
DETAILED DESCRIPTION
The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practicing the present disclosure are also possible.
As used herein, the terms “composite material” and “material” are used interchangeably and refer to materials formed by the combination of two or more distinct constituents, wherein the resulting material exhibits enhanced or synergistic properties that are not attainable by any individual component alone. Commonly, the composite material comprises a continuous matrix phase and a dispersed reinforcement phase, the latter being selected to improve one or more physical, mechanical, or thermal properties of the matrix. The matrix is a polymeric, metallic, or ceramic material, and the reinforcement includes, such as but not limited to, fibers, particles, or fillers. The interaction between matrix and reinforcement is engineered to produce a unified structure with improved characteristics, such as, but not limited to, increased tensile strength, reduced density, improved chemical resistance, or dimensional stability. Various types of composite materials are known in the art, but not limited to, fiber-reinforced composites, particle-reinforced composites, and layered or laminated composites. The procedure of forming a composite material depends on the nature of the matrix and reinforcement, and includes processes such as, but not limited to, hand lay-up, spray-up, filament winding, pultrusion, resin transfer molding (RTM), compression molding, or in-situ polymerization of reactive components. The resulting composite structure is further cured, molded, or processed to achieve the desired mechanical performance and dimensional configuration.
As used herein, the term “polyether polyol” refers to polymeric compounds containing multiple ether linkages and terminal hydroxyl groups, synthesized via the polymerization of alkylene oxides such as ethylene oxide, propylene oxide, or butylene oxide in the presence of an initiator containing active hydrogen atoms. In the composite materials, the polyether polyols serve as the primary polyol component in forming polyurethane matrices or resin, contributing to the flexibility, hydrophobicity, and chemical resistance of the cured composite. The polyols vary in molecular weight, functionality (diol, triol, or higher), and degree of branching, thereby allowing for the customization of mechanical, thermal, and curing characteristics in the final composite structure. The polyether polyols utilized in composite systems is selected from a range of high molecular weight polyols (>1000 g/mol) to impart elasticity and elongation, and low molecular weight polyols (<500 g/mol) to enhance crosslinking density and hardness. The incorporation of polyether polyol into the composite material is achieved by reactive blending with isocyanates under controlled conditions such as mixing, heating, and shear, optionally in the presence of catalysts, flame retardants, or chain extenders. Consequently, the resulting polyurethane or polyurethane-based matrix forms the continuous phase of the composite, effectively embedding reinforcing agents such as fibers, fillers, or particulate additives.
As used herein, the terms “triethanolamine” and “TEA” are used interchangeably and refer to a multifunctional organic compound with the chemical formula C6H15NO3, comprising three hydroxyl groups and one tertiary amine group. In the composite materials, the TEA functions as a reactive additive, surfactant, pH stabilizer, or catalyst in polyurethane-based systems. Advantageously, the TEA engages in both hydrogen bonding and nucleophilic interactions, thereby influencing the rate of urethane formation and enhancing the dispersion of additives such as flame retardants, fillers, or pigments. The incorporation of the TEA also contributes to improved homogeneity, controlled viscosity, and optimized reactivity during mixing, foaming, or curing stages of composite production. The triethanolamine is utilized in various concentrations depending on the application, typically ranging from 0.1 wt% to 5 wt% of the total formulation. The TEA is introduced as part of the polyol blend and acts synergistically with other catalysts or chain extenders to fine-tune the reaction profile. The technique of incorporating TEA involves pre-dissolving the TEA in the polyether polyol phase under controlled shear or temperature conditions to ensure uniform distribution throughout the composite material.
As used herein, the term “poly-iso-cyanate” refers to organic compounds containing two or more isocyanate functional groups (–NCO) per molecule that are highly reactive toward compounds containing active hydrogen atoms, such as, but not limited to, polyols, amines, or water. In the composite materials, the polyisocyanates serve as the primary isocyanate component in polyurethane or polyurea matrix systems, contributing significantly to the mechanical strength, chemical resistance, and thermal stability of the final composite. The polyisocyanates include aromatic types such as methylene diphenyl diisocyanate (MDI) and toluene diisocyanate (TDI), as well as aliphatic types such as hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI). The isocyanates are further modified to include functionalities such as allophanate, biuret, isocyanurate, uretonimine, or carbodiimide groups to adjust reactivity, viscosity, and processing characteristics. In composite material production, polyisocyanates are typically reacted with polyether polyols or other reactive hydrogen donors in a controlled stoichiometric ratio to form the polymeric matrix, which encapsulates and binds reinforcing agents such as fibers, fillers, or flame-retardant additives. The method of incorporating polyisocyanate may involve direct mixing with the polyol phase (two-component systems) or use in prepolymer form for moisture-cured or one-component systems.
As used herein, the term “flame retardant compound” refers to any chemical additive or reactive agent incorporated into a composite material formulation for the primary purpose of reducing flammability, slowing combustion, or suppressing smoke and heat release during fire exposure. The flame retardant compounds act physically (promoting char formation or forming protective barriers) or chemically (interfering with combustion reactions in the gas or condensed phases). In the composite materials, such compounds are included within the matrix phase, dispersed throughout a polyol or resin blend, or surface-applied to enhance fire performance characteristics. The additives are particularly critical in applications requiring compliance with fire safety regulations, including but not limited to construction panels, automotive interiors, electronic housings, and insulation materials. The flame retardant compounds are selected from a variety of halogenated (brominated or chlorinated organics), halogen-free (phosphorus-based, nitrogen-based), inorganic (aluminium hydroxide, magnesium hydroxide), or intumescent systems (expandable graphite, ammonium polyphosphate). The method of incorporation into the composite material involves direct blending into the reactive polyol or resin component under controlled shear to ensure homogeneous dispersion before mixing with isocyanate or curing agents. The concentration, particle size, and dispersion method of the flame retardant are selected based on target fire performance, mechanical property retention, and processing constraints.
As used herein, the term “expandable graphite” refers to a class of graphite-based flame retardant materials that are intercalated with acid-based compounds (sulfuric or nitric acid) such that, upon exposure to elevated temperatures (above 180°C), the graphite expands significantly in the direction perpendicular to the basal planes. The expansion creates an insulating, intumescent char layer that acts as a physical barrier to heat, oxygen, and flame propagation. In composite materials, the expandable graphite serves as a non-halogenated flame-retardant additive, offering improved fire resistance while maintaining mechanical and thermal stability. The effectiveness is attributable to the ability to expand rapidly and volumetrically, thereby protecting the underlying matrix during combustion. The expandable graphite is classified by particle size, expansion onset temperature, and expansion ratio, with common variants including fine, medium, and coarse mesh grades as well as high-expansion formulations (>200 mL/g). In composite formulations, expandable graphite is typically incorporated into the resin or polyol phase and dispersed under controlled shear conditions to ensure uniform distribution prior to reaction with an isocyanate or curing agent.
As used herein, the terms “controlled temperature range” and “temperature range” are used interchangeably and refer to a defined and regulated thermal window within which a composite material or its constituents are processed, cured, or activated to achieve specific performance characteristics. The temperature range is selected based on the thermal reactivity, phase transition behavior, or functional activation of components such as polyols, isocyanates, catalysts, or flame retardants. Further, maintaining the controlled temperature during processing ensures uniform mixing, predictable curing kinetics, optimized viscosity, and the prevention of premature reactions or thermal degradation. In thermosetting composite systems, the controlled temperature range governs the exothermic polymerization reactions and directly influences the mechanical strength, dimensional stability, and thermal performance of the final product. The implementation of a controlled temperature range in composite material manufacturing may involve the use of pre-heated components, in-line thermal regulation, heated molds, or staged curing profiles, depending on the processing method (e.g., resin transfer molding, reaction injection molding, or spray foaming). Different composite types may require distinct thermal regimes, such as low-temperature activation for expandable graphite (150–250°C), moderate curing ranges for polyurethane formation (typically 40–90°C), or post-curing cycles for enhanced crosslinking. Temperature control may be localized or applied globally across the production line, and may be actively monitored through embedded sensors, thermocouples, or feedback loops.
As used herein, the term “reactive group” refers to a chemically functional part present in a molecule that is capable of undergoing a specific chemical reaction under defined conditions, particularly with complementary groups to form covalent bonds. In composite materials, reactive groups play a critical role in initiating or propagating polymerization, crosslinking, or bonding reactions between matrix components (such as polyols and isocyanates) or between the matrix and reinforcing agents. Common reactive groups include hydroxyl (–OH), isocyanate (–NCO), amine (–NH2 or –NHR), carboxylic acid (–COOH), epoxy (–CH(O)CH2), and anhydride groups, among others. The selection and compatibility of these reactive groups determine the final network structure, mechanical performance, chemical resistance, and thermal stability of the cured composite. The method of employing reactive groups in composite formulations typically involves combining two or more components wherein at least one contains reactive groups that are complementary and capable of covalently bonding upon mixing or under external stimuli such as heat, moisture, or catalysts. For instance, in polyurethane composites, hydroxyl groups on polyether polyols react with isocyanate groups on isocyanates to form urethane linkages, establishing the polymer backbone of the matrix. The distribution, concentration, and functionality (number of reactive groups per molecule) are carefully controlled to balance processing characteristics such as gel time, viscosity, and cure profile. In some embodiments, reactive groups may also be present on surface-modified fillers or fibers to enhance interfacial adhesion within the composite. The strategic use of reactive groups thus enables the formation of durable, high-performance materials tailored to specific end-use requirements.
As used herein, the term “allophanate” refers to a secondary reaction product formed by the reaction of an isocyanate group (–NCO) with a urethane (carbamate) group, resulting in the formation of an allophanate linkage (–NH–CO–O–R–NH–CO–). In the composite materials, particularly polyurethane-based materials, the allophanate-modified polyisocyanates are employed to tailor the reactivity, viscosity, and thermal behavior of the isocyanate component. The presence of allophanate groups contributes to enhanced compatibility with polyols, improved storage stability, and controlled crosslinking behavior during curing. These modifications can result in composite matrices with improved mechanical strength, dimensional stability, and resistance to heat or hydrolysis. Allophanate groups may be introduced into polyisocyanate compounds via a controlled catalytic process, typically involving the reaction of an excess of isocyanate with urethane-containing intermediates in the presence of a metal catalyst under elevated temperature conditions. The resulting allophanate-modified isocyanates may be monomeric or polymeric, and vary in NCO content, molecular weight, and viscosity. In composite manufacturing, such modified isocyanates are incorporated into the reactive formulation with polyether polyols, flame retardants, or fillers under controlled temperature and shear conditions to ensure uniform dispersion. The allophanate structure enables fine-tuning of the pot life, cure kinetics, and post-cure rigidity of the composite material. The method of using allophanate-modified isocyanates is application-specific and is selected to meet regulatory requirements (e.g., low free monomer content) and performance targets such as impact resistance, thermal insulation, or flame retardancy.
As used herein, the term “carbodiimide” refers to a functional group containing the structural unit (–N=C=N–), formed through the reaction of isocyanates with amines or polyols in the presence of a suitable catalyst. In the composite materials, the carbodiimide-modified polyisocyanates are commonly employed to enhance the stability, reactivity, and compatibility of the isocyanate component within polyurethane or polyurea systems. The carbodiimide functionality improves the hydrolytic stability of the composite, reduces the tendency for free isocyanate groups to react with moisture, and modifies the crosslinking behavior, contributing to an optimized cure profile. The modification enhances the overall mechanical properties, resistance to aging, and environmental durability of the composite material. The carbodiimide-modified polyisocyanates are synthesized by reacting a polyisocyanate (such as MDI, TDI, or IPDI) with a carbodiimide precursor in the presence of a catalyst under controlled conditions at elevated temperatures. The resulting carbodiimide-modified isocyanates exhibit improved storage stability, reduced volatility of free isocyanates, and better control over the polymerization kinetics when mixed with polyols, flame retardants, or other additives. In the preparation of composite materials, carbodiimide-modified isocyanates are mixed with polyether or polyester polyols, with the resulting mixture processed under specific temperature, shear, and curing conditions.
As used herein, the term “uretonimine” refers to a functional group formed through the reaction of isocyanates with urethane compounds, resulting in the formation of a uretonimine linkage (–NH–CO–N=C–). In composite materials, particularly polyurethane systems, the introduction of uretonimine groups into the polyisocyanate structure modifies the reactivity and curing behavior of the system. The uretonimine-modified polyisocyanates are employed to enhance the storage stability, reduce the volatility of free isocyanate groups, and improve the mechanical properties of the resulting composite, such as strength, flexibility, and chemical resistance. The modification also provides improved resistance to moisture and aging, making the uretonimine particularly useful for applications in harsh environmental conditions. The synthesis of uretonimine-modified polyisocyanates involves the reaction of a polyisocyanate (such as MDI, TDI, or IPDI) with a urethane precursor in the presence of appropriate catalysts under controlled conditions. The resulting uretonimine-modified isocyanates are incorporated into polyurethane systems by mixing with polyols, flame retardants, or reinforcing fillers under shear conditions, with subsequent curing processes that enable crosslinking through isocyanate-urethane reactions.
As used herein, the term “isocyanurate” refers to a cyclic compound containing an isocyanurate ring structure, formed by the reaction of isocyanates, typically monomeric isocyanates like hexamethylene diisocyanate (HDI) or toluene diisocyanate (TDI), with each isocyanate group reacting to form a three-membered cyclic structure (–NCO–). In composite materials, isocyanurate-modified polyisocyanates are commonly employed to enhance the thermal stability, fire resistance, and mechanical properties of the resulting composite. The isocyanurate structure imparts improved resistance to high temperatures and accelerates the curing process, making it an ideal choice for applications requiring high-performance composites, such as in automotive, aerospace, and construction industries. The incorporation of isocyanurate groups into polyisocyanates can also provide better compatibility with polyols, flame retardants, and other additives used in composite formulations. The synthesis of isocyanurate-modified polyisocyanates involves the reaction of an excess of isocyanate monomers with catalysts to form the isocyanurate ring structure. These isocyanurate-modified isocyanates can be used in composite materials by combining them with polyether polyols, polyester polyols, or other reactive resins under controlled conditions. The method of incorporating isocyanurate-modified polyisocyanates into a composite formulation involves blending these modified isocyanates with polyols and other additives, followed by curing at elevated temperatures to promote crosslinking and form the final thermoset structure. The incorporation of isocyanurate groups is particularly beneficial in achieving desired fire-retardant properties, improved dimensional stability, and enhanced overall performance, while also reducing the likelihood of degradation or disintegration under extreme thermal conditions.
As used herein, the term “graphite flakes” refers to thin, plate-like particles of natural or synthetic graphite, characterized by a high aspect ratio, as the thickness of the flakes is significantly smaller than the lateral dimensions. The flakes possess excellent thermal and electrical conductivity, making the flakes valuable in composite materials, particularly for enhancing thermal management, mechanical properties, and flame retardancy. The graphite flakes are incorporated into composite formulations to provide a thermally conductive filler that helps to distribute heat uniformly across the material, preventing localized overheating and improving overall thermal stability. Additionally, the graphite flakes contribute to the mechanical strength, rigidity, and flexibility of the composite, depending on their size, aspect ratio, and dispersion within the matrix. The graphite flakes are available in different types based on the origin and processing, including natural graphite, which is derived from mined graphite deposits, and synthetic graphite, produced by heating carbon-containing precursors at high temperatures. The natural graphite flakes typically exhibit larger particle sizes and are more commonly used for applications requiring high thermal conductivity and flame resistance.
As used herein, the term “threshold temperature” refers to the specific temperature at which a composite material undergoes a significant change in its physical, chemical, or mechanical properties, marking a transition from one state to another. The temperature is critical in determining the operational limits and performance characteristics of the composite material in various applications, especially under varying environmental conditions. The threshold temperature may correspond to the onset of irreversible deformation, softening, glass transition, or crystallization, depending on the type of material. In polymeric composites, for example, the threshold temperature is often related to the glass transition temperature (Tg) or the melting point of the matrix material, beyond which the composite material loses its structural integrity or functional properties. The types of threshold temperatures in composite materials may include the glass transition temperature (Tg), the softening point, the thermal degradation temperature, or the phase transition temperature, each representing a different type of thermal response. The glass transition temperature is particularly significant in thermoset or thermoplastic composites, marking the temperature at which the polymer transitions from a rigid, glassy state to a more flexible, rubbery state. In thermoplastic materials, the melting point serves as a critical threshold temperature. In composite materials containing flame retardants or fillers, the threshold temperature may also indicate the onset of chemical reactions or decomposition. The method of determining the threshold temperature involves thermal analysis techniques, such as differential scanning calorimetry (DSC), which measures the heat flow associated with phase changes, or thermomechanical analysis (TMA), which assesses changes in the material’s dimensions under controlled heating. These techniques provide precise data on the temperature at which critical transitions occur, allowing for the optimization of composite materials for specific thermal performance requirements.
As used herein, the term “decomposition temperature” refers to the temperature at which a composite material begins to chemically break down or degrade, resulting in the release of volatile components, gases, or the onset of structural failure. The temperature is a critical parameter in determining the thermal stability and service life of the composite. The decomposition temperature is influenced by various factors, including the nature of the matrix resin, the type and concentration of reinforcing agents, and the presence of flame retardants or stabilizers. The composite materials containing thermosetting resins, such as polyurethanes or epoxy, exhibit a well-defined decomposition temperature. The types of decomposition temperatures vary depending on the composite components and the chemical structure. The decomposition temperature is further influenced by the incorporation of certain additives, such as flame retardants, which either raise or lower the decomposition temperature depending on their chemical composition and mode of action. The technique of determining the decomposition temperature typically involves thermal analysis techniques such as thermogravimetric analysis (TGA) or differential thermal analysis (DTA), which monitor the mass loss or heat flow of the composite material as the composite is subjected to a controlled temperature ramp.
As used herein, the term “volumetric expansion ratio” refers to the change in volume of a composite material upon exposure to a specific external stimulus, such as heat, moisture, or pressure. The volumetric expansion is a crucial parameter for composite materials used in applications with dimensional stability under temperature fluctuations or environmental conditions is critical, such as in thermal insulation, flame-retardant coatings, and sealing materials. The material exhibiting a high volumetric expansion ratio provides enhanced protection by expanding to fill voids or gaps, thereby improving the effectiveness in specific applications, such as fire resistance or thermal insulation. The types of volumetric expansion ratios are categorized based on the nature of the external stimulus and the behavior of the composite material. For instance, the thermal expansion refers to the increase in volume due to heating observed in materials containing phase-changing additives such as expandable graphite, foaming agents, or certain polymers. The moisture-induced expansion occurs as composite materials absorb water or other fluids, leading to an increase in volume. The pressure-induced expansion also occurs, particularly in materials containing microencapsulated agents or gases. The method of determining the volumetric expansion ratio involves measuring the initial and final volumes of the composite material after exposure to the specified external stimulus.
In accordance with an aspect of the present disclosure, there is provided a composition for forming a composite material, the composition comprising:
- a first compound comprising a polyether polyol in an amount of at least 35% weight of total weight of the composition and a triethanolamine in an amount of at least 2% weight of the total weight of the composition;
- a second compound comprising a modified poly-iso-cyanate in an amount of at least 30% weight of the total weight of the composition; and
- a flame retardant compound comprising an expandable graphite in an amount of at least 30% weight of the total weight of the composition.
The above-mentioned composition for forming a composite material as described herein is designed to achieve enhanced thermal stability, flame retardancy, and mechanical performance. The first compound comprises a polyether polyol, which is a key component in the formulation of the composite material. The polyether polyol is present in an amount of at least 35% by weight of the total composition, providing a robust matrix for the formation of a polyurethane or polyurea-based composite. Further, the inclusion of triethanolamine (at least 2% by weight) serves a dual purpose: acting as a catalyst in the curing process and enhancing the reactivity of the polyisocyanate component. The combination allows for a controlled curing rate and improved crosslinking, leading to a composite with enhanced mechanical properties such as tensile strength, rigidity, and elongation. The presence of triethanolamine also contributes to improving the stability of the composition during processing. The second compound in the composition comprises a modified poly-isocyanate, which constitutes at least 30% by weight of the total composition. The modified poly-isocyanate serves as the reactive hardener in the composite formulation. The modified poly-isocyanate reacts with the polyether polyol to form urethane linkages that provide the structural integrity and durability of the composite. The modification of the poly-isocyanate involves the introduction of groups such as isocyanurate, allophanate, or carbodiimide, which improve the material's thermal stability, reduce moisture sensitivity, and enhance the long-term performance of the composite. Advantageously, by incorporating the modified poly-isocyanate, the resulting composite material exhibits superior flame retardancy, mechanical strength, and resistance to environmental degradation. Furthermore, the flame retardant compound, specifically the expandable graphite, is included in the composition in an amount of at least 30% by weight. The expandable graphite provides flame-retardant properties due to the ability to expand when exposed to heat. Upon thermal activation, expandable graphite swells to form a char layer that acts as an insulating barrier, which helps to retard the spread of fire by reducing heat transfer and limiting oxygen access to the material. The expandable graphite also contributes to the overall thermal stability of the composite material, providing both passive and active fire protection. Furthermore, the inclusion of expandable graphite enhances the composite’s ability to resist ignition and maintain structural integrity in the presence of fire, which is particularly beneficial for applications in industries such as transportation, construction, and electrical components. The synergy between the flame retardant, polyether polyol, and modified poly-isocyanate results in a composite material that not only meets stringent fire safety standards but also maintains excellent mechanical properties and environmental durability. Therefore, the above-mentioned composition provides significant advantages in terms of flame retardancy, mechanical strength, and environmental resistance and is suited for applications in industries requiring high-performance materials with fire safety, thermal stability, and long-term durability.
In an embodiment, the first compound, the second compound, and the flame retardant compound are homogenously mixed under a controlled temperature range. The homogenous mixing of the first compound, the second compound, and the flame retardant compound under the controlled temperature range ensures uniform dispersion of all components within the composition. Further, the controlled temperature range ensures that the polyether polyol is maintained at a temperature suitable for effective interaction with the modified poly-isocyanate without premature reaction or decomposition. Similarly, the temperature is controlled to prevent the premature expansion of the expandable graphite, ensuring that the flame retardant compound remains stable until the material is exposed to elevated temperatures during curing. Furthermore, the resulting homogenous mixture provides consistency in the composite's properties and ensures that each component is uniformly distributed throughout the material, contributing to the overall performance of the composite. The techniques of mixing involve heating the individual components to the required processing temperatures before introducing the components into a high-shear mixer or other suitable mixing apparatus. Subsequently, the mixture is agitated at a controlled speed to facilitate uniform blending of the polyether polyol, modified poly-isocyanate, and flame retardant compound. The controlled speed ensures that the expandable graphite is properly dispersed and not aggregated, thereby preventing inconsistencies in the fire-resistant properties of the final product. The controlled temperature range is critical to optimize the reactivity of the components, ensuring complete curing without premature gelation or loss of desired properties. Consequently, the composite material with uniform mechanical, thermal, and fire-resistant properties is formed and thereby enhancing the composite material's performance and ensuring that the desired characteristics are maintained throughout the entire composite structure. Furthermore, the homogenization improves the overall material performance by preventing the aggregation of flame retardants, ensuring that the fire resistance is evenly distributed across the composite, and optimizing the interaction between polyols and poly-isocyanates. The mixing enhances processing efficiency and material performance, reducing the defects or inconsistencies in the final composite, and providing an ideal balance of flame retardancy, mechanical strength, and stability under varying temperature conditions.
In an embodiment, the first compound comprises glycerin in an amount of at least 3% weight of the total weight of the composition. Specifically, the glycerin interacts with the polyether polyol to improve the crosslinking density of the material, enhancing the flexibility and durability of the final composite. Additionally, glycerin functions as a plasticizer, helping to reduce the viscosity of the polyol mixture, which helps in the processing and handling of the composition during formulation and subsequent curing. Further, the presence of glycerin contributes to the thermal stability of the composite material by promoting a more controlled rate of curing, which results in a more uniform polymer network. Furthermore, the glycerin enhances the material’s moisture resistance and dimensional stability by reducing the hygroscopic swelling, thus improving the composite's long-term performance in humid or wet environments. The procedure for preparing the composition involves adding glycerin to the polyether polyol in a predetermined amount, ensuring that the glycerin constitutes at least 3% by weight of the total composition. Subsequently, the glycerin is mixed with the polyether polyol and other components, including triethanolamine, modified poly-isocyanate, and flame retardant compounds, under controlled conditions to achieve homogeneous mixing. The glycerin's presence helps to regulate the reaction rate during the curing process, preventing the occurrence of exothermic reactions that lead to material defects or inconsistencies. Additionally, the glycerin helps to optimize the reactivity between the polyether polyol and the modified poly-isocyanate, ensuring the formation of a well-cured composite with enhanced structural integrity. Furthermore, the glycerin reduces the viscosity of the polyol blend, which enhances the processing capabilities and allows for better dispersion of other components, such as flame retardants and curing agents.
In an embodiment, the polyether polyol comprises a mixture of high molecular weight polyols and low molecular weight polyols. The high molecular weight polyols (having a molecular weight greater than 1000 g/mol) provide the primary structural strength of the composite material. The high molecular weight polyols contribute to the composite’s overall mechanical strength, elasticity, and long-term stability. Further, the low molecular weight polyols (molecular weights ranging from 200 g/mol to 1000 g/mol) improve the reactivity of the polyether polyol mixture, enabling better crosslinking with the modified poly-isocyanate. Therefore, the combination allows for enhanced control over the composite’s hardness, flexibility, and processability. Specifically, the high molecular weight polyols contribute to the bulk properties, such as stiffness and tensile strength, and the low molecular weight polyols contribute to curing efficiency, ensuring that the polymerization reaction proceeds at a controlled rate. Further, by optimizing the ratio of high to low molecular weight polyols, the material properties of the composite are fine-tuned to achieve desired characteristics, including enhanced impact resistance, dimensional stability, and durability. The procedure for preparing the composition involves selecting and combining high molecular weight polyols and low molecular weight polyols in a predetermined ratio to meet the desired specifications of the final composite material. The polyols are mixed with other components, such as triethanolamine, modified poly-isocyanate, and flame retardant compounds, under controlled temperature and shear conditions. The use of a mixture of polyols allows for fine-tuning the reactivity and viscosity of the mixture, leading to improved processability during manufacturing and better performance in the final cured product. The combination of high and low molecular weight polyols allows for tailored properties in the final composite, balancing flexibility, strength, and reactivity. Therefore, the resulting composite material demonstrates improved processability, higher mechanical strength, and greater durability, making the material suitable for a wide range of applications requiring both flame retardancy and robust mechanical properties.
In an embodiment, the modified poly-isocyanate comprises at least one reactive group selected from an allophanate group, a carbodiimide group, a uretonimine group, and an isocyanurate group. The reactive groups are incorporated into the poly-isocyanate structure to enhance the chemical properties and reactivity of the poly-isocyanate with polyols in the composite material. The inclusion of the specific reactive groups improves the overall thermal stability, moisture resistance, and durability of the resulting composite material. Specifically, the allophanate and carbodiimide groups contribute to increased crosslinking density and improved resistance to hydrolysis, and the uretonimine and isocyanurate groups enhance the fire retardant properties of the composite material by providing additional thermal stability. Consequently, the modifications ensure that the composite material maintains the mechanical properties and structural integrity under extreme conditions, such as high temperatures or exposure to moisture, and are critical for applications requiring high-performance, long-lasting materials. The procedure of preparing the composition involves selecting the poly-isocyanate that is modified to include one or more of the above-mentioned reactive groups. Subsequently, the modified poly-isocyanate is homogenously mixed with the polyether polyol, triethanolamine, and flame retardant compounds under controlled conditions, ensuring that the chemical reactions occur at the appropriate rate and that the reactive groups effectively interact with the polyols to form the desired polymer network. Furthermore, the presence of reactive groups such as allophanate, carbodiimide, uretonimine, or isocyanurate enhances the curing process by promoting additional crosslinking points, resulting in a more durable and stable composite. The groups also improve the flame retardancy of the composite by promoting the formation of a char layer or the release of non-combustible gases during thermal degradation, contributing to enhanced fire resistance.
In an embodiment, the expandable graphite comprises graphite flakes of a size in the range of 180 to 300 micrometres. Specifically, the selection of the specific flake size is critical to optimize the flame retardant properties of the composite material. The graphite flakes within the above-mentioned size range possess optimal surface area and structural characteristics that enhance the expansion behavior of the graphite after exposure to heat. Further, during thermal activation, the expandable graphite undergoes a physical expansion process, wherein the flakes swell and form a protective char layer that significantly delays the spread of flames. Furthermore, the chosen flake size ensures that the graphite expands efficiently to form a consistent and durable char barrier, which provides enhanced fire protection by reducing heat transfer and limiting the availability of oxygen to the burning material. Furthermore, this size range offers a balance between ease of dispersion in the composition and the ability to expand effectively during exposure to heat, leading to improved overall flame retardancy and thermal stability of the composite. The graphite flakes are exposed to elevated temperatures during curing or processing, at which point the expandable graphite reacts to form a protective, insulating char layer. This char formation is critical in enhancing the flame resistance of the composite. The size of the graphite flakes is controlled to prevent clumping or agglomeration, which would otherwise hinder the expansion process and reduce the flame retardant efficiency. By ensuring an optimal particle size, the composition achieves consistent and reliable flame retardant performance across the entire material. The use of expandable graphite flakes in the range of 180 to 300 micrometers ensures a highly effective flame retardant mechanism, as the graphite expands to form a protective char layer that resists heat transfer and limits oxygen access, thereby improving the composite's fire resistance. The selected size range facilitates optimal dispersion of graphite flakes throughout the composite material, ensuring uniform flame retardancy and minimizing the risk of inconsistencies in material performance.
In an embodiment, the flame retardant compound is configured to initiate expansion of the composition at a threshold temperature lower than a decomposition temperature of the composite material. The configuration ensures that the flame retardant mechanism is activated at an early stage, before the composite material begins to degrade thermally. The threshold temperature is pre-selected to be within a range as the expandable graphite particles begin to expand and form a protective char layer, providing an initial barrier to heat and flame. The early expansion helps to insulate the composite material, limiting the rate of heat transfer and protecting the underlying composite structure from thermal degradation. Further, the controlled activation of the flame retardant compound at a lower temperature ensures that the composite material responds to heat stress and prevents flame propagation more effectively. The procedure for achieving the activation involves selecting flame retardant compounds, such as expandable graphite, that exhibit an expansion onset at a threshold temperature below the material's decomposition temperature. The expandable graphite is incorporated into the composite matrix in a manner that ensures its effective dispersion and reaction to thermal conditions. During the preparation process, the material is exposed to controlled heating or curing conditions that ensure the flame retardant compound remains inert until the threshold temperature is reached. Further, by configuring the flame retardant compound to expand at a threshold temperature lower than the decomposition temperature of the composite material, the composition activates a protective mechanism early, ensuring better fire resistance before thermal degradation occurs. The early expansion of the flame retardant compound forms an effective barrier to heat and flame, reducing the risk of combustion and improving the overall fire safety of the composite material.
In an embodiment, the expandable graphite exhibits a volumetric expansion ratio directly proportional to the exposure temperature range. The volumetric expansion ensures that the degree of expansion of the expandable graphite is dynamically responsive to the temperature increase, providing an efficient and scalable flame retardant mechanism. Further, with the rise in temperature, the graphite flakes swell, with the extent of the expansion increasing proportionally with the temperature. The controlled expansion creates a thick, insulating char layer that acts as a barrier to heat, oxygen, and flame propagation. The ability of the graphite to expand in proportion to the temperature ensures that the composite material adapt to varying thermal conditions, offering a tailored fire response that improves the overall thermal stability and flame resistance of the material. The proportional expansion enhances the material's performance in both moderate and extreme heat scenarios, providing consistent protection across a wide range of fire and temperature events. The expandable graphite is dispersed uniformly throughout the composite matrix during processing to ensure optimal distribution and expansion characteristics. When exposed to elevated temperatures, the graphite reacts by expanding in a controlled and predictable manner, with the degree of expansion corresponding to the exposure temperature range. The controlled expanding ensures that the material will exhibit an increasing level of fire resistance as the temperature rises, improving the material's ability to prevent flame spread and protect underlying structures. The direct proportionality between the volumetric expansion ratio of the expandable graphite and the exposure temperature range enables the composite material to dynamically adjust the fire retardant properties in response to varying thermal conditions. Therefore, the temperature-dependent expansion creates a scalable flame retardant effect, with the degree of protection increasing as the temperature rises, ensuring that the material is optimally protected at all stages of a fire or heat exposure.
Based on the above-mentioned embodiments, the present disclosure provides significant advantages such as (but not limited to) flame retardancy, mechanical strength, and environmental resistance, and is well-suited for applications in industries requiring high-performance materials with fire safety, thermal stability, and long-term durability.
In the description of the present invention, it is also to be noted that, unless otherwise explicitly specified or limited, the terms “disposed,” “mounted,” and “connected” are to be construed broadly, and may for example be fixedly connected, detachably connected, or integrally connected, either mechanically or electrically. They may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Modifications to embodiments and combinations of different embodiments of the present disclosure described in the foregoing are possible without departing from the scope of the present disclosure as defined by the accompanying claims. Expressions such as “including”, “comprising”, “incorporating”, “have”, and “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components, or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural where appropriate.
,CLAIMS:WE CLAIM:
1. A composition for forming a composite material, the composition comprising:
- a first compound comprising a polyether polyol in an amount of at least 35% weight of total weight of the composition and a triethanolamine in an amount of at least 2% weight of the total weight of the composition;
- a second compound comprising a modified poly-iso-cyanate in an amount of at least 30% weight of the total weight of the composition; and
- a flame retardant compound comprising an expandable graphite in an amount of at least 30% weight of the total weight of the composition.

2. The composition as claimed in claim 1, wherein the first compound, the second compound, and the flame retardant compound are homogenously mixed under a controlled temperature range.

3. The composition as claimed in claim 1, wherein the first compound comprises glycerin in an amount of at least 3% weight of the total weight of the composition.

4. The composition as claimed in claim 1, wherein the polyether polyol comprises a mixture of high molecular weight polyols and low molecular weight polyols.

5. The composition as claimed in claim 1, wherein the modified poly-isocyanate comprises at least one reactive group selected from an allophanate group, a carbodiimide group, a uretonimine group, and an isocyanurate group

6. The composition as claimed in claim 1, wherein the expandable graphite comprises graphite flakes of a size in the range of 180 to 300 micrometres.

7. The composition as claimed in claim 1, wherein the flame retardant compound is configured to initiate expansion of the composition at a threshold temperature lower than a decomposition temperature of the composite material.

8. The composition as claimed in claim 1, wherein the expandable graphite exhibits a volumetric expansion ratio directly proportional to the exposure temperature range.