first you have to decide what type of nanocomposite you want to prepare? With polymer what nano you want to add to make nanocomposites? Then only you can decide..
Extrusion and compounding of micro/nano fillers is still a popular technique to produce nanocomposites industrially and this is because extrusion and blending is an available, low cos, large throughput and convenient tech. Years of research works have been dedicated to modify nanocomposites or processing conditions to have significant dispersion of nanofillers. However, there are other methods like in situ synthesis of nanofiller within the matrix, solution blending, infusion of particles and so on.