Sepiolite: A Powerful Clay Filler For The Advanced Materials

Sepiolite (Sep) is a powerful and promising filler, alternative to the. synthetic shape-controlled silica filler for many industrial applications. It possesses unusual structure, producing a “checkerboard” type pattern, where the sheets are covalently bonded, so they cannot be exfoliated. For this, the breaking down of Sep fibres aggregate is still a challenge to take advantage of the peculiar sepiolite shape for designing nanostructured materials. In this context, soft-chemistry methods, and the use of functionalizing molecules, often enables the generation of tailored inorganic-organic hybrid interfaces, making Sep fibres exploitable as active component in many formulation products with unique properties. In the last decade, we are focused on the different possibility to modulate sepiolite bulk properties including surface chemistry and morphology, particle size, shape, and porosity, to design systems employed in several applications, such as polymer nanocomposites (NCs), catalysis, photoresponsive materials and biomedical products.1 The talk will present some examples of the modification and applications of Sep based materials, with some more hints on those which have now reached a quite mature stage of development and for which marketable solutions are currently or shortly available, such as the “SmartNET ™ Technology”2 and the “next generation double function fillers”,3 industrially developed in Pirelli Tyre laboratories. Limits and perspectives will be addressed, especially in the light of the challenging opportunity to control and tuning hybrid interfaces of Sep clay filler with organic species and macromolecular matrix.