**3. Conclusions**

Since its inception, graphene has drawn worldwide interest due to its high quality and amount of work. The technology and applications of graphene-reinforced polymer matrix nanocomposites are showing significant development. However, various challenges in concerns of synthesis methods, costs, quantity qualities and applications must be addressed and resolved to fully realize the potential of graphene nanocomposites. For illustration, if we consider physical synthesis methods for graphene such as sonication, exfoliation and cleaving, the end product (graphene) can have a reduced aspect ratio, which can drastically degrade the reinforcement, and binding interactions, and thermal and electrical properties of both graphene and nanocomposites. Both graphene and its derivatives have proved their promise as prospective choices as reinforcements for high-performance nanocomposites, as shown in this review. The effects of reduced loadings of graphene and its derivatives, which result in high levels of strength and stiffness and superior mechanical properties, have been described in many studies. The high dispersion quality of graphene and its derivatives in various host matrices has also been discussed in many types of research. As previously stated, several challenges must be overcome in achieving large-scale, defect-free graphene exfoliation with high quality and good characteristics. Since graphene tops the charts with its exceptional properties, the graphenebased product highlights itself in various applications. Dispersion and distribution of graphene into polyolefin are very important to develop and improve the electrical and thermal conductivity, mechanical properties and gas barriers of the polymers. To

attain most of these characteristics, it is necessary to have exfoliation, an interconnected graphene network.

However, dispersions and distribution of graphene in polymers are challenging. Partially get good dispersion by sonicating graphene into a co-solvent with the polymer before co-precipitation or drying to a film, or by scattering graphene in a monomer and polymerizing in situ to make a composite. In the right circumstances, solvent-processed composites lock the graphene into a well-dispersed state in the solvent; nevertheless, to improve dispersibility and interaction with the polymer matrix, the graphene must usually be modified. In-situ polymerization can produce better outcomes, which could be because graphene is involved in the polymerization process, or because polymer chains are grafted onto graphene sheets.
