In recent years, nano-composite materials have proved to be the vital engineering material as its several useful properties and features draw diverse interest in the research industry and community. Graphene is a nano-composite based material, made of numerous nanosized fillers and a polymer matrix. It possesses many characteristic properties such as great electrical, optical, and mechanical properties, high thermal conductivity, and highly efficient composite material. Although many kinds of research were carried out that majorly evaluate and demonstrate the effective structural application of graphene-based materials in various industries, yet there is limited diverse knowledge that is gathered in this research field for researchers and design engineers. The objective of this paper is to review the literature related to recent advancements using graphene as reinforcement in structural composites and its recent developments based on various hypotheses and studies conducted in past few years. It is being observed from previous studies that Graphene possesses substantial potential for industrial applications in transportation, conductive materials including thermal and electrical materials, construction fields, and aerospace. In this paper, surveys of those pieces of literature were carried. Moreover, the historical perspective and major technological advancements were assessed and reviewed. Therefore, this study investigates various hypotheses, key concepts, frameworks, and models that are employed to utilize the reinforcement of graphene in different structural composites in recent years. And, the information gathered in this study can be used further to get up-to-date on new developments and/or emerging concepts, conduct studies on future prospects and prepare strategies to resolve the current challenges in this field.
Graphene is a nano-composite based material, made of numerous nanosized fillers and a polymer matrix (Abbasi, Akbarzadeh, Kouhi, & Milani, 2014). Graphene along with its various derivatives is having a large number of applications in several areas that include structural reinforcement, thermal and electrical conductivity, and great energy storage capacity that is similar to two-dimensional materials that possess higher strength, large surface area, and high thermal and electrical conductivity (Adetayo & Runsewe, 2019). In recent years, nano-composite materials have proved to be the vital engineering material as its several useful properties and features draw diverse interest in the research industry and community (Adetayo & Runsewe, 2019). It has been observed in different studies that the preparation method employed for Gr preparation is expensive and complicated and its cost of preparation can only be reduced for those composites that comprise other polymers or inorganic materials (Bae et al., 2010).
It is being observed from previous studies that Graphene possesses substantial potential for industrial applications in transportation, conductive materials including thermal and electrical materials, construction fields, and aerospace (Abbasi, Akbarzadeh, Kouhi, & Milani, 2014). Combined materials including Gr and abnormal materials are usually made using chemical reduction, sinter molding, or chemical insertion (Gonçalves et al., 2016). Graphene should be able to reduce numerous biological defects, including lower specific energy, lesser photoelectric conversion, and decreased density (Fortin, Elbadry, & Yokoyama, 2020). It is noticed that the decrease in the stated defects consequently leads to an exponential increase in the applications of the Graphene components that were applied in devices such as sensors, transistors, capacitors, and many more. Several techniques are employed to process graphene compounds and polymer materials (Surendranathan, 2019). These solution mixing techniques include in situ polymerization method and melt mixing, out of which melt mixing is revealed to be the best mixing technique (Zhou, Yao, Chen, Wei, & Xu, 2013).
Graphene has varied and diverse applications such as it are employed in polymer materials (Thomas, 2017) to reduce the weakness or enhance the distributed performance of the polymer composite of graphene in other systems (Smita Mohanty, Nayak, Kaith, & Susheel Kalia, 2015). This review study is focused to investigate various hypotheses, key concepts, frameworks, and models that are employed to utilize the reinforcement of graphene in different structural composites in recent years (Seretis, Kouzilos, Manolakos, & Provatidis, 2017). It is being observed from previous studies that Graphene possesses substantial potential for industrial applications in transportation, conductive materials including thermal and electrical materials, construction fields, and aerospace. Although many kinds of research were carried out that majorly evaluate and demonstrate the effective structural application of graphene-based materials in various industries, yet there is limited diverse knowledge that is gathered in this research field for researchers and design engineers (Ramalingame, Bautista-Quijano, Alves, & Kanoun, 2019). That is why the current preparation methodologies of Graphene composite material is expensive and complex. Additionally, the molding process in the graphene preparation lowers the efficiency of the polymer composition and affects its reinforcement adversely (Mostovoy & Yakovlev, 2019). Therefore, the objective of this paper is to review the literature related to recent advancements using graphene as reinforcement in structural composites and its recent developments based on various hypotheses and studies conducted in past few years.
Graphene is a dual structure made up of carbon atoms. Its unique design offers its amazing performance for a variety of applications. Its specific location, low power consumption, very low resistance, and very high-temperature are structures based on its unique construction. In the preparation of composite materials, the performance of Graphene is necessary because the fine structure of Graphene has a weak connection with other substances, which leads to its efficient distribution (Gupta, Sakthivel, & Seal, 2015). Currently, the main synthetic methods used for Graphene synthesis include chemical deposition, epitaxial growth, mechanical extraction, and reduced oxidation; The oxidation-reduction method has been used in many types of applications.
The Graphene polymer composition contains a stable, fragrant hydrocarbon series; its edges and cracks have a more responsive function. Graphene composites, such as graphene oxide, contain a large number of active oxygen-containing groups, which can react with other active groups and form chemical bonds (Kumar, Singh, & Ramkumar, 2020). Graphene performance can be divided into the following two categories: non-covalent performance and covalent performance. Modification of spatial function using empty bonds mainly involves the formation of bonds between chemical elements and the Gr surface by intermolecular forces, which have the advantage of maintaining mass formation and desirable Gr or GO structures without damaging the structure or its many structures.
At the same time, the transformation of the earth's function using non-covalent bonds can be used to improve Gr distribution, but the effect of strong graphene is unstable and its internal strength is weak. By comparison, the modification of the covalent bond function is achieved by introducing a functional group that is able to form a double-binding bond or another group containing oxygen instead of Gr or GO. Compared to non-covalent bond performance, covalent bond performance is stable but affects performance because it damages the Gr structure (Idowu, Boesl, & Agarwal, 2018).
There are several pieces of research that state that the primary composite material of Gr that are organic are ceramic, metal, or inorganic reinforced composite materials, and their methodology selection is based on various inorganic material properties of graphene that involves the application of these composite materials (Ashutosh Tiwari & Shukla, 2014). In this study, various preparation methodologies, their merits, demerits, and futuristic scope of different applications of graphene are investigated and demonstrated (Bonaccorso et al., 2012). The preliminary methodologies employed for types of Graphene preparation involve hydrothermal electrodes method, sinter modeling, sol-gel methods, and chemical reduction techniques (Buzaglo et al., 2016).
Modeling of sinter is a simple and lucid fabrication technique where the shape of the product that has to be fabricated is needed to resemble closely to the desired final product. In this methodology, the authors tried to develop an option of sintering the products with less pressure application (Dasari, Nouri, Brabazon, & Naher, 2017). Moreover, they explained the merits and demits of this technique that this method has low efficiency to produce and manufacture while it can be variedly used to fabricate ceramics, alloys, and other composite materials. The authors of this paper were successful in describing the material fabrication by hydrothermal technique. They demonstrated that graphene when arranged in matrices possesses great controllable shape of grains at low production costs and requiring more types of equipment at the same time (Celis et al., 2016). The chemical reduction technique proved to be promising too as the authors claimed that this is a low-cost and simple method that yields great performance results but there may be some possibilities that the reduction agent can be dangerous or hazardous (Alexopoulos, Paragkamian, Poulin, & Kourkoulis, 2017).
The development of an easy process that is completely controllable named Sol-gel has the ability to mix uniformly with Graphene matrices at the molecular scale but this technique has lower efficiency and micropores can be observed visibly in the composite material due to which the combination may tend to shrink and get de-shaped unwillingly (Allen, Tung, & Kaner, 2010). These studies efficiently described, demonstrated, and evaluated various key principles and processes.
Graphene-based nanocomposites- and polymers show promising growth in technology and use. However, a few key challenges need to be addressed and addressed in order to determine the strength of graphene-based nanocomposites in terms of manufacturing, cost, and utilization (Rajeshkumar & Naik, 2018). Many researchers have demonstrated their in-depth study of Graphene composite materials. As a result of in-depth studies in Gr, basic research and the use of Gr computers have improved and demonstrated that Gr has great potential for use in aerospace, transportation, medical equipment, electrical and thermal equipment, and building materials (Seretis, Kouzilos, Manolakos, & Provatidis, 2017). With the composting process between iron oxides and Gr, hydrothermal reduction methods or chemical reduction methods are generally accepted, and the resulting product is often used by supercapacitors. In Gr / Inorganic structures, Gr provides good strength and can be used as synthetic materials used in the manufacture of basic metals; Sinter shapes are often accepted in these types of combinations (Mondal & Khastgir, 2017).
Due to the unique structure with two Gr features, it can also be used in sensors and catalysts. Ceramic / Gr alloys are less readable than steel / Gr alloys. Sintering is widely accepted in the construction of ceramic / Gr mixtures, and these types of construction are often used for structural reinforcement. In terms of Gr/polymer composite materials, soluble solvents are beneficial in industrial production while a blending solution or situ polymerization can be very helpful in laboratory preparations. Gr can combine with different polymers and provide significant benefits in the preparation of sensors, active films, organic matter, and anti-corrosion coating, among other applications (On, 2015). However, there are a number of issues that need to be resolved. The process of preparing G Gr is complex and expensive; therefore, preparing an inexpensive pile is difficult. Temperatures for processing unusual materials such as metals and clay are high and can destroy the structure of Gr. Therefore, processing costs and costs are higher when Gr and inorganic materials are combined.
When Gr is combined with organic polymers, Gr tends to exist in an agglomerate manner due to its specific location and higher surface strength, and there is greater electrostatic and Van der Waals forces between Gr sheets (Sarkheil & Rahbari, 2018). Agglomerates easily cause degradation in a polymer-built environment, which is not conducive to improving its physical properties. Therefore, the search for effective modification methods and the availability of good dispersion and the dreaded effect on polymer matrixes are very important in the production of suitable nanocomposites (Maurya, 2019). In the future, the methods of repair and interaction of Gr's assets and integrated structures must be improved so that composite ultimately encourages the advancement of material engineering.
It is hereby concluded that graphene is the most useful and captivating reinforced material in the nanotechnological world. Moreover, it is estimated that the market for graphene would rise by 70-75% by the end of 2025 (Guo, Lv, & Bai, 2019). The exceptional properties of the carbon material possess the appropriate potential to cause a revolution in various fields of applications such as medicine, electronics that include transistors, smart automation technologies, engineering, industrial designs, and energy batteries, and various such areas (Gupta, Sakthivel, & Seal, 2015). Moreover, in the world, the advancements in reinforced Graphene has grabbed the attention of developers, scientists, students, and engineers. The rapid graphene usage in today’s world is resulting in the replacement of ongoing technology and is opening new avenues and market opportunities for advanced technological advancements (Klaus Friedrich & Ulf Breuer, 2015). It has also been studied and demonstrated that graphene integration in several composites is proving to be highly promising as it possesses more features and characteristics, has higher efficiency and durability, and is lighter in weight than other compositions. For achieving a fulfilled and complete potency of Graphene, the highest quality is required to be produced largely and should also be economical while employing eco-friendly techniques for graphene synthesis (Xu & Li, 2012).
In this review study, detailed concepts and frameworks of traditional composites and advancements in the reinforcement of Graphene were studied and reviewed. Their merits and demerits were revealed, and the futuristic scope and applications in the various field were discussed in detail. Later on, the literature survey was carried and different historical backgrounds of composites based on graphene were studied. Some studies were focused on integrating numerous mechanisms to enhance the reinforcement of graphene within the composite materials. While others demonstrated their work in designing frameworks, developing models and concepts, and creating suitable manufacturing processes for the polymer reinforcement. Lastly, it is concluded that various exciting and interesting opportunities are existing which can be innovated and created to bring out more advancement in the technology using Graphene polymer composites. These designs and developments could lead to various practical applications and insights in the context of new technological design and advancement.
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