Modificação das propriedades dos polímeros comerciais de SBR e NBR a partir da incorporação de nanopartículas sintéticas

Abstract

Numerous efforts have focused on the search for new materials involving lower cost, greater durability and, especially, lower environmental impact. In this sense, polymer nanocomposites have become the focus of many research groups because of their superior mechanical and thermal properties. In this work, nanocomposites of SBR and NBR with silica nanoparticles and synthetic clay Laponite, without and with the surface modification with silane 3-(trimethoxysilyl) propyl methacrylate (TMSPM), were prepared by means of simple mix of components using the colloidal route. The nanocomposites of SBR and NBR with Laponita showed exfoliated structure, with the presence of clay tactoids intercalated by the polymeric matrix, with homogeneity at the nanometric level and lower molecular mobility. The nanacomposites had increase in the thermal stability than the pure polymer and the mechanical properties showed a increase in storage modulus, loss modulus and damping properties (noise, vibration). Nanocomposites of SBR and NBR with Laponite functionalized with TMSPM also been prepared and presented structure intercaled with the presence of clays tactoids. There was a reduction in molecular mobility and increased in the glass transition temperature (Tg) with increase of the Laponite content. The silica nanoparticles were synthesized by controlled hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in an alcoholic medium. In addition, silica nanoparticles are functionalized with TMSPM. The nanocomposites of SBR and NBR with silica nanoparticles with and without the surface functionalization were prepared by the colloidal route. Nanocomposites showed silica agglomerates in the form three-dimensional structure nanoparticles with and without modification in the SBR and NBR. The nanocomposites of SBR and NBR with silica showed a decrease in Tg, around 10 °C, increase in storage and loss modulus and damping properties with the increased amount of silica.