It is shown that the addition of coiled carbon nanotubes (CCNTs), to polymer matrices confers a two-fold increase of the relative electrical permittivity, in addition to an improvement in the mechanical characteristics. A four-fold augmentation of the elastic modulus and a two-fold improvement in the ultimate tensile strength (compared to the polymer) at similar to 2 vol% filler fractions was also obtained. Such attributes are shown to be superior to those obtained through the use of linear (both single-walled and multi-walled) CNTs. (c) 2013 Published by Elsevier Ltd.