A review of recent advances on the properties of polypropylene - carbon nanotubes composites

Polypropylene (PP) has a wide range of engineering applications in automobile, biomedical, energy, machine parts, electronic packaging etc. However, PP lacks some desired engineering properties such as good thermal properties and mechanical strength. For instance, PP is known for its low melting temperature, high flammability and low heat resistance. This has resulted in continuous improvement in various properties of PP via modification of its matrix. One of the ways this has been achieved is by incorporation of foreign bodies in form of reinforcements in the PP matrix. The recent discovery of carbon nanotubes (CNTs) has further paved the ways for advancing the properties of PP via the development of PP-CNTs composites. Such composites have not only shown improved engineering properties but retain the lightweight and flexibility of PP. The advanced engineering properties recorded by various studies using PP-CNTs composites are due to the good properties of PP in conjunction with the excellent properties of CNTs such as high thermal conductivity, strength, electron mobility and formation of conductivity networks in the PP matrix. Although the development of PP-CNTs composites faces challenges of high agglomeration and incompatibility of CNTs in the matrix, the moves towards addressing the hurdles and achievements recorded so far are encouraging. Therefore, this review investigated the contribution of CNTs on various advanced engineering properties of PP-CNTs composites. Various results drawn from previously published literature within the decade were tabulated for future academic references and industrial purposes. Current hurdles faced by PP-CNTs composites, future prospect and their advanced engineering applications were discussed.