Interfacial effects on the dynamics of ethylene-propylene copolymer nanocomposite with inorganic clays

We studied relaxation dynamics of poly(ethylene-co-propylene) grafted diethylmaleate/montmorillonite nanocomposites at different clay loading, as well as of residue samples obtained through an extraction procedure performed on the nanocomposite. The modification of the relaxation properties, i.e. relaxation time and dielectric strength, of structural and secondary processes has been studied to investigate interface interaction between polymer and montmorillonite. In order to investigate the dynamic properties of the polymer strictly interacting with the clay, samples were prepared by washing the nanocomposite with a solvent of the pure polymer. The results evidenced the presence of competing effects of interaction between polymer and inorganic filler and of the reduction of the polymers chains cooperativity.