A method for treating polymer particles is disclosed. Polymer particles and a liquid are provided. The method includes the following steps (a) and (b). (a) Mixing said polymer particles with said carrier liquid to form a dispersion of said particles in said carrier liquid at a concentration of at least 0.1 g/L, based on the volume of the dispersion. (b) Subjecting the dispersion to microfluidization treatment thereby causing particle stretching, particle size reduction and increasing the surface area per unit mass of the polymer particles. Also disclosed is a particulate composition comprising polymer particles mixed with nanoplates derived from a layered material, wherein the particulate composition has a BET surface area of at least 10 m.sup.2/g. Furthermore, there is disclosed a method for the manufacture of a component formed of a composite of a polymer with a dispersion of nanoplates. The particulate composition is provided as a precursor particulate. Then the precursor particulate is formed into the component.