The Effect of the Nb₂O₅ Dispersion on Ethylene Vinyl Acetate to Obtain Ethylene Vinyl Acetate/Nb₂O₅ Nanostructured Materials

This work investigated the effect of niobium pentoxide nanoparticles (Nb₂O₅) on the molecular organization of an ethylene vinyl acetate copolymer (EVA) matrix containing 28% vinyl acetate groups, according to their dispersion and distribution in the polymer matrix. Due to niobium pentoxide's characteristics and properties, it may interfere in the chemical and UV resistance, as well as in the EVA mechanical properties, increasing mechanical resistance. The EVA/Nb₂O₅ nanocomposite films, with Nb₂O₅ varying from 0.25 to 1% in relation to the total EVA mass, were prepared by solution casting. The Nb₂O₅ was well dispersed with the use of ultrasound. These films were mainly characterized by X-ray diffraction and low-field nuclear magnetic resonance through relaxometry, in order to obtain responses on the structural organization and molecular dynamic, respectively, and consequently to understand the effect of the nanoparticles on the EVA matrix. The results showed that the addition of Nb₂O₅ to the EVA matrix caused changes in its crystallinity and molecular mobility, due to the new interactions formed by the good dispersion of nanoparticles and also their distribution in the EVA matrix, changing the copolymer characteristics due to the formation of a new material.