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Epoxy resins are a class of thermoset polymeric materials used in various applications. They possess a range of good properties such as high toughness, rigidity, wear resistance, and durability. Besides, its strong adhesion ability and chemical resistance make them useful for several applications. Epoxies are utilized in the coatings and adhesive industries to protect and bond solutions to surfaces exposed to harsh environments. It provides corrosion resistance for metal structures and wear resistance for materials such as polymers, ceramics, and wood. They are also used in making lightweight and high-strength composite materials for use in the aerospace, automotive, and marine industries where they are used to manufacture parts such as the wings of an aircraft, fuselage, car body panels, boat hulls, and cargo tanks. Therefore, epoxy is a vital component of contemporary industrial and construction applications.
Federal University of Technology Akure, Ondo State, Nigeria
Oladele Isiaka Oluwole
Federal University of Technology Akure, Ondo State, Nigeria
Akinwekomi Akeem Damilola
Federal University of Technology Akure, Ondo State, Nigeria
Bichang’a Denis Ondieki
Kirinyaga University, Kerugoya, Kenya
Makinde Akindeji Ibrahim
Federal University of Technology Akure, Ondo State, Nigeria
*Address all correspondence to: barakaisola@gmail.com
1. Introduction
One of the most versatile thermosetting polymers is epoxy resin. Thermosetting polymers are usually made up of monomers and oligomers typically combined with a liquid hardener, such as another resin or catalyst. When the resin and hardener react together, a crosslinked structure is created by joining the monomers and oligomers into lengthy polymer chains [1]. The crosslinked structure resists sliding and rotation when a load is applied leading to a higher stiffness, strength, and hardness than thermoplastics. Epoxy resin possesses two or more epoxy groups referred to as epoxide or oxirane, in the molecule. It is widely used in several industries due to the properties they possess both during processing and after curing. It is capable of showing low viscosity during processing and requires a little amount of pressure to form products. They can also combine with several types of hardeners at low temperatures and elevated temperatures. After curing, they exhibit low cure shrinkage and residual stresses and gives a good chemical and heat resistance [2, 3, 4].
The properties of epoxy resin can range from hard and strong to tough and resilient. Depending on their constituents and their areas of applications, they can be modified to reach glass transition temperatures between 60°C and 250°C by using various prepolymers. Epoxy resins exist in two groups, the aromatic epoxy saturated ring and the nonaromatic saturated ring epoxy. The aromatic epoxy saturated ring comes from the monomer diglycidylether of bisphenol A (DGEBA) and is widely used for outdoor application due to its resilience to UV radiation while 3,4-epoxycyclohexyl-3,4-epoxycyclohexana carboxylate is the source for the nonaromatic epoxy [1, 5]. Diglycidylether of bisphenol A, or DGEBA, is the most widely used epoxy resin, making up more than 75% of all epoxy usage [6, 7]. Figure 1 depicts DGEBA’s chemical structure. Other common epoxy resin is novolac epoxy resin, bisphenol F epoxy resin, aliphatic epoxy resin, glycidlyamine epoxy resin, and bio-based epoxy resin [8]. Some of characteristics of these epoxy resins and their applications are shown in Table 1.
Figure 1.
Structure of diglycidylether of bisphenol A (DGEBA) [7].
Table 1.
Comparison of epoxy resin type, their properties, and applications [8, 9, 10, 11, 12].
Epoxy resins find applications in numerous industries as shown in Figure 2, for different use. They can be used as structural adhesives, surface coatings, engineering composites, and electrical insulation [1]. The percentage of their applications in these fields is shown in Figure 3. They are being highly used in electrical appliances, automobile parts [13], marine industries, aerospace industries, biomedical industries [14], jewelry, leisure, sports, and esthetics. Epoxy resin has been used to replace several components due to advancement in materials technology. They are being used to replace parts made from woods, metals, and other materials to save production costs, increase efficiency, and reduce weight in various industries particularly the automobile and aerospace industries [15]. They have also been combined with both natural and synthetic fibers to make parts such as car bumpers, dashboards, underfloor protection, fuselage, wind blades, boats, and electronic components [15, 16]. The need of epoxy resin is continuously growing everyday which this has drastically soared their global market [8, 9].
Figure 2.
Applications of epoxy resin (a) Helicopters; (b) floor finish; (c) electronic industry and applications; (d) wind turbines; (e) aircraft structure; (f) bicycle parts; (g) automotive structure; (h) ships and marine vehicles; (i) epoxy adhesives; (j) rail and railroad repair; (k) firearm coating; (l) sports, i.e., tennis racket [17].
Figure 3.
Percentage of applications of epoxy resins in various fields [8].
Due to rapid advancements, continuous development of technology, and need for sustainable materials in different industries, the use of epoxy resins is constantly evolving [15], and new types of epoxy resin with improved properties are being developed. Epoxy resins are being incorporated with nanofillers and bio-based epoxy resins from natural sources are being developed to enhance environmental sustainability [17]. Also, they are being used in emerging applications like flexible electronics, self-healing concrete, and biomedical devices. Therefore, an updated review on epoxy resin applications is necessary to provide an overview of the latest advancements, address the challenges and opportunities in different industries, and guide future research and development efforts.
An adhesive is a high-strength glue that bonds different component materials together. They can be used on a wide range of substrates including for bonding metals to metals, metals to composites, metals to ceramics, metals to polymers, and even composites to composites [18]. They can also be used for bonding parts made from wood and cement and come in different forms such as in film form or paste from. Figure 4 shows some of their applications. Epoxy adhesives also known as epoxy glue are one of the leading adhesive solutions and key use of epoxy resins in sectors including the aerospace, automotive, construction, manufacturing, biomedical, and electronics sectors [4]. Epoxy adhesives are used because of the unique properties which they possess such as good bonding performance; low-temperature curing; waterproof, heat and chemical resistance; low shrinkage on cure, absence of volatile solvents, low creep, product durability; and improved engineering efficiency [4, 7]. They also account for almost 40% of market value, making them the greatest single end use. Epoxy resin adhesives have the ability to adapt to many material surfaces, including metals, wood, concrete, glass, ceramics, and many plastics compared to traditional joining methods, and this is due to the presence of polar hydroxyl and ether groups in the resin [19]. Also, different curing agents used in epoxy resins such as amines, aromatic amines, modified amines, polyamides, anhydrides, or acids offer different properties, resulting in their diverse and versatile properties. Their high resistance to environmental factors such as water, chemical exposure, pressure, and elevated temperature makes them suitable for replacing mechanical bonding methods such as screwing, drilling, and chiseling [20]. Epoxy adhesives are used for metal bonding, bonding of skin and core in sandwich composites, concrete bonding and wood adhesive, and a variety of other applications as stated in Table 2.
Figure 4.
Pictures of some applications of epoxy resin adhesive [23].
Epoxy type
Application
Function
References
Novolac epoxy
Bonding of concrete to steel and masonry in buildings, electrical component encapsulation, printed circuit board encapsulation
It gives high thermal, fire, and chemical resistance to the component and also enhances flame retardancy
The use of adhesives in joining different parts together offers numerous advantages including the elimination or reduction of the need for mechanical fasteners which reduces cost; reduction of occurrence of fatigue cracking compared to metal connections as drilled holes for fasteners are potential sites for the initiation of fatigue cracks and provision of a lighter bond which reduces the overall weight of the part and enables the design of smooth external surfaces [34].
Epoxy for adhesives applications comes majorly in two forms; epoxy film adhesives and epoxy paste adhesives. Film adhesives provide a high strength, durability, and resistance to environmental factors to a bonded joint and has found applications mainly in aircraft structures such as wing structures, fuselage panels, honeycomb core components, and lightning strike protection [35, 36]. The film is applied by placing it in between the components to be bonded and then heated and pressurized to form a rigid bond. The epoxy paste adhesives come as a one-part system or a two-part system. The one-part systems are prepared and supplied by mixing all formulated components in advance including epoxy resin and curing agent. They are spread on the components and then cured by heat or pressure while the two-part system consists of a resin and hardener which are mixed together first before been applied on a component [37, 38]. Table 3 shows some of the characteristics of film epoxy adhesive and paste epoxy adhesive.
Film epoxy adhesives
Paste epoxy adhesives
Film epoxy adhesives come in a preformed shape like solid sheets or rolls
Paste epoxy adhesives come in a paste form and are usually viscous and spreadable
They are suitable for bonding components with a flat and large surface areas
They are suitable for bonding irregular, complex or small surface areas and for filling gaps
It does not require mixing or metering, and application is clean and precise
The one-part system does not require mixing while the two-part system requires mixing of the resin and hardener
They are usually cured with heat or pressure
They can be cured at room temperature or with heat
The bonding gives a high strength and consistent performance
The bonding provides a high impact and chemical resistance
They are mostly used in aerospace structures such as honeycomb and sandwich panels
They are mostly used in the automotive, construction, electronic repairs and in general bonding
They possess high thermal stability and highly suitable for elevated-temperature applications
They have a high bond strength and mostly used for room temperature applications
They generally exhibit a long shelf life especially when stored properly
The one-part system has a long shelf life while the two-part system has a shorter shelf life once mixed
Table 3.
Characteristics of film and paste epoxy adhesives [19, 39].
Coatings or paints are very common and can be seen almost everywhere such as in cars, on wall buildings and even on household materials. A coating is a thin film of liquid mixtures that are applied on the surface of materials for different functions. They can be applied for decoration purposes, for protection of the surface of a material from corrosion and external environments, and to impart specific properties on a material [40, 41]. Examples of specialized applications of surface coatings include anti-fouling paints for ship hulls and coatings for food and beverage containers to protect the contents in them as shown in Figure 5.
Epoxy resin is highly utilized in used industrial coating and has applications in different industries including pipeline protection in the oil and gas industries, warehouse floor sealing, coating of automobile parts and marine equipment, and coating of pipe fitting [43]. They are majorly used to protect material surfaces and to avoid corrosion and decay of metals and other materials.
Epoxy resin coatings provide a great degree of flexibility to a variety of substrates, and this makes them more affordable than other alternative solutions to protection of surfaces [44, 45]. They possess excellent mechanical properties such as resistance to abrasion and corrosive species, toughness, durability, and endurance, and this makes them an excellent choice of surface treatment for different parts in harsh environments. They are used as the protection layer in automobiles, to protect oil and gas pipelines or wastewater pipelines against corrosion, to improve the performance of metals used in factories, concrete flooring, and other areas with heavy footage. They are also used to improve the corrosion resistance of painted materials by incorporating them as binders in paints [1]. They have found applications in several industries including electrical, naval, locomotive, and industrial production application.
Epoxide resin and polyamine hardener are incorporated together to induce an electrochemical reaction which forms epoxy coatings. When the two materials are mixed together, curing occurs after some hours, and the wet epoxy layer is converted to a tough and durable solid after which they can be used for different application. They can be incorporated with other resins such as phenolics, alkyds, and amino-resins, they can also be esterified by heating with resin acids. Although some solvent-based methods were once employed, they have mostly been phased out for safety and health reasons. Example of use as surface coatings is the two-part epoxy system highly used in marine industry for prevention of corrosion on ship and boats parts made from steel. For fluidized bed coating of metal parts to prevent corrosion, epoxy coating systems are also offered in powder form, complete with an appropriate hardening system. Electrostatic spraying is an additional method of processing them. Preheating metal parts to 150°C is a standard practice in these applications, and this is done to promote adhesion and start the coating system’s curing process. After this, reheating of the coating is done to completely cure the resin. Powder coatings are highly helpful for the application of thick coating layers to items with irregular and complex shapes since they are electrically and chemically resistant. Because epoxy is reactive, the coatings made from them come out tough and adhere firmly to the substrate compared to thermoplastic powders. Intumescent coatings used in steel constructions’ fire protection are also frequently made from epoxy resins. In this case, heat flux causes the resin phase to expand 10–20 times, gradually transforming it into a carbonaceous char with reduced thermal conductivity that protects the metallic material underneath [7].
3.1 Epoxy corrosion resistance coating
Epoxy resin has gained widespread application in anti-corrosion materials due to its exceptional mechanical qualities, which include corrosion protection, resistance to chemicals, and high adherence to metal surfaces. Epoxy resin containing two or more epoxy groups is commonly used for this application, and also due to the presence of several functional groups in them, they can be tailored to meet different applications. By undergoing condensation events with hydroxyl and isocyanate groups and ring-opening reactions with amino and carboxyl groups, the epoxy and hydroxyl groups can facilitate modification [46].
Several modified epoxy resins have been developed by to enhance corrosion resistance. Organosilicon resins have been added to epoxy to improve corrosion resistance of some materials by reducing the surface energy and forming hydrophobic layers; adding polyaniline to epoxy coatings increases its conductivity and enhance corrosion resistance by producing a passivating effect on the substrate [47, 48, 49].
3.2 Road and bridge coatings
Worldwide, the use of polymers in construction materials is growing daily, and epoxy resin is crucial to the creation of effective building materials [50]. Concrete and masonry mortar based on epoxy resin in particular have a lot of promise since they offer intriguing features, qualities, and uses [51]. Epoxy resin-based materials have proven to be able to meet many of the requirements of both present and future building projects while also overcoming many of the limits of traditional Portland cement-based materials. The surfaces of roads and bridges have been repaired and protected with epoxy resin coatings. Many polymers and traditional Portland cement have a longer setting time and weaker adhesion, and thus, they cannot be used as binding materials when restoring older buildings. Conversely, epoxy has a high level of adhesion, and by altering the kind and amount of hardener in the mixture, the setting time of mortar and concrete made with epoxy resin may be customized [50]. They are used for the treatment of spalling which is a problem normally encountered on roads and bridges. Spalling occurs due to the accumulation and combination of thaw–freeze cycles, road gritting, and spillage by vehicles. Epoxy resin with amine hardeners at room temperatures is commonly utilized for this treatment. The resin and hardener formulations form a film when coated on a structure, and it prevents spalling on bridge surfaces and road structures. It also slows down the growth and propagation of cracks when used for sealing cracks on these structures. It bonds the damaged parts into an integral part and prevents the penetration of water into the structure. Epoxy resin can also be used for several purposes in construction such as road marking, fuel spill prevention, lightweight surfacing for bridge decks, waterproof layer between concrete and toppings, repairing slippery road surfaces, and repairing roads made from concrete [52].
The properties of cured epoxy resin depend on the type of epoxy resin, the curing agent used, and the quantity of curing agent used. Because the qualities of cured epoxy resins rely on the kind of epoxy resin, curing agent, and curing technique; if epoxy resin, hardener type, and hardener concentrations are not chosen appropriately for use in a composition, the material may not perform its intended function [53]. It is therefore important for people involved in construction works to study polymeric materials technologies so as to be able to utilize the versatility that polymeric materials provide for the development of the polymer-modified concrete technology.
The exceptional properties of epoxy resin such as chemical stability, high strength, and thermal resistance have spurred their use in the development of composite materials. Epoxy composites have become indispensable in various high-tech industries including the aerospace, marine, automotive, construction, electronics, sports, and even in biomedical application [54]. Different forms of reinforcement such as fibers (natural and synthetic), fillers, and additives are usually incorporated into epoxy resin to make epoxy composites. The addition of these reinforcements helps to achieve the desired property of the composite such as improved mechanical properties (like tensile strength and fracture strength), electrical conductivity, thermal stability, biocompatibility, environmental resistance, and environmental sustainability [55].
The ability of epoxy resin to be incorporated with various types of fibers and fillers compared to other thermosetting polymers have enabled the achievement of these specific properties. Additionally, they mix well with aramid, glass, carbon, and natural fibers, allowing for the optimization of features including stiffness, delamination resistance, and interlayer strength [55]. Fatigue resistance and other mechanical attributes of epoxy composites are greatly enhanced by the addition of nanoparticles like silicon dioxide (SiO2) or titanium dioxide (TiO2). Additionally, the incorporation of graphene into epoxy resin matrices results in a significant improvement in electrical conductivity and thermal shock resistance, creating new opportunities in sophisticated technologies such as electronics [54, 56, 57]. In short-fiber and hybrid graphene composites, the combination of fibrous and particle fillers has a synergistic effect that improves resistance to delamination and cracking. One type of hybrid reinforcement that increases toughness and ensures better stress transfer within the material is polyaryletherketone interlayers. These advancements enable the creation of composites with remarkable properties for challenging conditions [54, 58].
Due to various environmental benefits and increased environmental awareness, environmentally friendly products are the focus of industrial companies, and sustainable development is becoming more and more popular worldwide. Researchers keep exploring the production and development of renewable composite materials that are fully or partially bio-based, known as biocomposites. Prior to this awareness, synthetic fibers and fillers have been used to produce epoxy composites; however, certain limitations like high energy demand, high cost, adverse environmental impact, and non-biodegradability have spurred researchers to look for an alternative such as natural fibers and fillers [59]. Natural fibers are used in the making of several eco-friendly materials and offer numerous advantages such as reduction of pollution, conversion of waste to valuable materials, reduction in the depletion of petroleum reserves, and reduced materials and energy usage [60]. Natural fiber-based epoxy composites or epoxy biocomposites consist of natural fibers or filler in the epoxy resin matrix and are less expensive and more environmental friendly than synthetic fiber epoxy composites and have found numerous applications in automobiles, aircraft, constructions, electronics, and other industries. Some of their applications in this field is shown in Table 4. Epoxy resin has also been reinforced with natural fibers like sisal, coir, bagasse, pineapple, agave, kenaf, jute, egg shell powder, snail shell powder, chitosan, HAp to obtain different properties such as high stiffness and strength, reduced weight, biocompatibility, and most especially, environmental degradability. The mechanical properties of epoxy resin reinforced with some of these fillers and fibers is presented in Table 5. They have been used for the production of parts such as multipurpose panels, roofings, storage tanks, beams, and pedestrian overpasses.
Industry
Applications
Function
Marine
Boat hulls and decks, buoys and underwater equipment
They provide resistance to water, saltwater, and corrosion, thereby ensuring long-term durability in harsh marine environments
Sporting goods
Bicycle frames, golf clubs, tennis rackets, and skateboards
They provide an aspect ratio by reducing the weight of the components while enhancing their performance
Aerospace
Wings, fuselage panels, engine parts, honeycomb structures, and interior structures
a. They improve fuel efficiency and performance by reducing the weight of the components.
b. They also provide excellent mechanical properties and durability.
c. They provide resistance to heat and flame
Automotive
Automobile body panels, underfloor protection
Reduced weight leads to improvement in fuel efficiency while maintaining strength and durability
Electronics
Printed circuit boards, lighting poles, and power line insulators
d. They serve as materials for encapsulation and potting of sensitive components.
e. They also offer excellent electrical insulation properties
Biomedical
Implants, prosthetics, and imaging (MRI)
They provide biocompatibility and durability, thereby ensuring safe and reliable performance
Structural
Beams, panels, and insulated boards
They provide high strength and durability
Chemical
Subterranean storage tanks, composite containers for substances, ducts, and stacks
f. They offer resistance to chemicals and corrosion
g. They provide thermal stability, strong adhesion, and structural integrity
Table 4.
Applications of epoxy resin in composite materials [60, 61, 62].
Epoxy resin type
Bio-Filler/ Reinforcement
Tensile strength (MPa)
Flexural strength (MPa)
Modulus (GPa)
Impact resistance (kJ/m2)
Epoxy (DGEBA)
Flax fiber
75–100
120–140
5.5–6.0
35–40
Epoxy (DGEBA)
Jute fiber
12.46
39.08
—
2.63
Epoxy (DGEBA)
Hemp
75.14
126.07
Epoxy (DGEBA)
Coir
13.05
35.04
—
17.5
Epoxy
Sisal
132.73
288.6
Epoxy (DGEBF)
hemp
60–85
100–130
4.5–6.5
30–38
Bio-based Epoxy (e.g., epoxidized linseed oil)
Flax fiber
45–65
75–95
3.0–4.2
22–28
Table 5.
Epoxy resins vs. mechanical performance in bio-based composites [63, 64, 65, 66].
Among the novel materials utilized in composites are nanomaterials, also known as nanocomposites, which stand out from traditional composite materials because of their superior mechanical qualities. They are used in different forms such as polymer-clay nanocomposites and carbon nanotubes to improve the properties of materials used in high-performance applications like aerospace, biomedical industries, and automobile [67]. Carbon-based epoxy composites which are one of the promising materials used in advanced technologies have shown unique chemical and physical properties with the incorporation of nanofillers into them. Likewise, nanoclay-reinforced polymer-based composites have attracted a lot of interest from the academic and business communities because even a small amount of nanoclay shows good optical transparency and significantly improves the mechanical performance of the neat polymers [68, 69].
Epoxy resin development primarily relies on non-renewable petroleum resources, typically epoxy monomers of the DGEBA type. Most of the basic ingredients used to make these thermoset resins are hazardous to human health. These epoxy resins are made with compounds that have the potential to harm human health and the environment, such as causing cancer and disrupting hormones. The creation of epoxy resins generated from biological sources is therefore gaining traction as a more sustainable and environmentally friendly substitute. Compounds of biological origins include lignin, rosin, vanillin, and eugenol, and vegetable oils (e.g., soybean, linseed, and castor oil), rosin, and sugars/carbohydrates like sorbitol and isosorbide offer a good starting point for the creation of environmentally friendly epoxy resins. Phenolic rings found in these compounds are perfect for producing high-performance polymers. Using biomass as a raw source, bio-based epoxy resins have been the subject of extensive research in recent decades. To increase epoxy resins’ uses and competitiveness, bio-based epoxy resins with functional attributes such as recyclability, flame retardancy, degradability, and antibacterial properties have been developed [70, 71, 72]. Applications for these resins are numerous and include 3D printing, composites, adhesives, and coatings. With the growing demand from consumers for sustainable products, the development of bio-based epoxy resins is expected to continue, driven by their balance of performance, cost-efficiency, and environmental benefits.
Bio-based epoxy composites can be synthesized through various methods, such as glycidylation reactions using plant phenols and epichlorohydrin, double-bond oxidation with oxidative reagents like hydrogen peroxide, or the introduction of acetal structures using aldehydes and polyols as shown in Figure 6. These processes leverage renewable resources like bio-oil, vanillin, and glycerol to create epoxy resins with unique properties. Functionalization techniques can further enhance these resins with flame retardancy, recyclability, or shape memory capabilities. While the addition of dynamic bonds or the formation of reversible dynamic covalent bonds (like ester bonds) during the curing process creates recyclable bio-based epoxy resin or shape memory epoxy resin, the addition of elements like phosphorus or structures that produce high char yield at elevated temperatures, such as rigid structures or heterocyclic structures in the intermediate, is used to create flame retardancy or recyclability properties [70, 73, 74, 75].
Figure 6.
Bio-epoxy resin synthesis using phenolic chemicals by (A) glycidylation reaction and (B) double-bond oxidation [70].
Epoxy resin being a highly versatile polymeric material has also found applications in electronics and insulating materials. Their capacity to function dependably in harsh environments, such as high temperatures, high humidity, and UV radiation exposure, is the main factor behind their widespread use. They also have good mechanical qualities, resistance to chemicals and water, and exceptional electrical and dielectric insulating qualities [76, 77, 78, 79]. Epoxy resin can be used for sealing electronics devices made from metals and other plastics. They also serve as coatings for protecting materials from impact, shock, vibrations, moisture, and chemicals [80]. Epoxy resins have been employed in a range of electronic components including switch gear, motors, and generators [81] as shown in Table 6.
Reinforces solder joints, prevents cracking under thermal cycling
Table 6.
Uses of epoxy resin polymer in electronics [79, 82, 83, 84].
Epoxy resins are also widely used in biomedical applications for different functions. Their properties such as biocompatibility, mechanical strength, flexibility, lightweight, and resistance to harsh environments have spurred their usage. In human clinical settings, collagen-based epoxy composites have been utilized as aortic heart valves, vascular grafts, and wound dressings; there is a lot of promise for shape memory polymer foams in biological applications like embolic sponges. Because of their exceptional chemical inertness, low electrical and high thermal conductivities, wide optical transparency, and other special qualities, nanodiamond-epoxy derivatives have found extensive use in biological systems (Figure 7) [23, 85].
Figure 7.
Applications of epoxy resin in biomedical engineering (a) Prosthetic limbs [86, 87] (b) 3D printed maxillofacial.
Epoxy composites have the potential for further development in terms of their properties and applications, which could significantly impact their use in a wide range of industries. The prospects for future development are based on improving mechanical properties, standardizing for extreme conditions, and developing sustainable materials with little or no adverse effect on the environment. The epoxy resin market is projected to grow from $12.64 billion in 2024 to around $13.76 billion in 2025, with a compound annual growth rate (CAGR) of 8.9%. By 2029, the market is anticipated to reach $19.93 billion, driven by advancements in electronics, compatibility with biological materials, circular economy initiatives, and the proliferation of electric vehicles [88]. The growing use of bio-based formulations, which are more environmentally friendly and sustainable, is one of the major developments. Also, it is anticipated that the development of smart epoxy resins with sensors for real-time monitoring, rapid curing methods for quicker production, and improved adhesion qualities would increase the range of uses for these resins. Because epoxy resins are lightweight, strong, and long-lasting, the market is also benefiting from the growing demand in the electronics, automotive, and aerospace industries. Because of growing industrial demand, environmental initiatives, and technological advancements, the epoxy resin market is anticipated to expand rapidly.
Epoxy resin demand has grown significantly due to technological advancement in various fields and is predicted to continue doing so in the years to come. Epoxy resins have found applications in various industries ranging from automotive and aerospace to constructions, electronics, and biomedical engineering due to their unique combination of high mechanical strength, good chemical resistance, and high thermal stability. There have also been numerous advancements in the production of bio-based and functional epoxy resin to enhance sustainability and due to environmental concerns. The spur in the development of more sustainable and high-performance epoxy resins will definitely drive their future applications making them an indispensable material in the global market.
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Written By
Makinde-Isola Baraka Abiodun, Oladele Isiaka Oluwole, Akinwekomi Akeem Damilola, Bichang’a Denis Ondieki and Makinde Akindeji Ibrahim
Submitted: 20 May 2025Reviewed: 28 July 2025Published: 02 October 2025
Open access peer-reviewed chapter
