There are numerous techniques for preparing polymer nanocomposites, including blend and in-situ methods as well as emulsion polymerization for polymer synthesis. The impact of nanometal concentration and oxides on the properties of the prepared polystyrene nanospheres is of interest and studies were being done on the mechanical, optical, electrical, and antibacterial activities of polymer nanocomposites which have proven to enhance the polymer's qualities for usage in various applications.