A Brief Review of the Effect of Silica Nanoparticles on the Crystallinity of HDPE-Based Nanocomposites

Today, one of the most widely used thermoplastic polymers in the world is polyethylene, which is used in various industries. Polyethylene has found many applications due to its unique properties such as low cost of production and very good processability. However, the weak mechanical properties of this polymer compared to metals have led to the use of additives such as various nanoparticles to improve it in most cases. For this reason, in recent years the development of various nanocomposites based on polyethylene has become important. Silica is the common nanoparticles in the field of polymer nanocomposites, which the special features such as easy access, low toxicity, and high surface area, and molecular stability have made this nanoparticle a suitable option for improvement the physical and mechanical properties of polymers. Also, in some cases, in order to solve the problem of the improper dispersion and agglomeration of these nanoparticles, the surface modification of these mineral materials by different methods has been the focus of researchers. In the recent studies, the use of pure and surface-modified silica nanoparticles in thermoplastic matrix, including polyethylene has been reported to improvement the physical and mechanical properties of the polymer. In this paper, the effect of pure silica nanoparticle and its surface-modified types on the crystallinity of nanocomposite based on various types of polyethylene has been reviewed.