| abstract |
A method for preparing nanocomposites and nanocomposite polymeric products by dispersing nanoparticles in a polymer either by melt processing or by solution processing and bringing about migration of the nanoparticles from the bulk interior to the surface of the nanocomposites so as to produce a new asymetric type of nanocomposite in which the concentration of the nanoparticles on the surface is many times higher than in the interior bulk of the nanocomposite. These surfaces impart highly enhanced properties to the nanocomposites as compared to the pristine polymer and to nanocomposites that have not undergone the migration process, including stability against aging, longer shelf life, higher hydrophobicity, higher wear resistance, higher hardness and lower friction. The new surfaces of the nanocomposite polymeric products are produced by inducing migration of the nanoparticles to the surface thereby producing a concentration gradient below the surface. |