The type, structure, quantity and combination of fillers as well as the interface adhesion are key parameters to achieve the desired properties profile of the matrix material. The correct filler selection and appropriate additives lead to special properties that are not innate to metals giving for example, the possibility of thermally conductive plastics that conduct heat but are still electrically insulating.

Smooth surfaces are necessary, amongst other things, for parts that are to be subsequently electroplated. The better thermal conductivity can be felt; they are cooler and can thus further enhance the cooling effect of any electroplated layer that is applied.

One good, vivid example of an application area is for the push-buttons in lifts or for light switches.  When manufactured from highly-filled polyamides, they offer not only a cool touch effect but also a superior quality look and feel compared to conventional plastic buttons.