Avaliação do uso de caulim calcinado em composição de borracha nitrílica para aplicação na indústria de óleo e gás

Abstract

This work aims to study the effect of a hybrid filler system containing carbon black and calcined kaolin on a typical composition for an artifact used on the oil and gas industry. Six formulations were established. One of them contains only carbon black (F01: 50CB/0CC), other three with hybrid filler system (F02: 35CB/15CC, F03: 25CB/25CC and F04: 15CB/35CC), another one with only calcined kaolin (F05: 0CB/50CC) and a composition with no filler (pure gum). The mixtures were prepared and done on a two-roll mixer according to ASTM D-3187.Then they were tested for mechanical, rheological, thermal and morphological properties, in order to study the extent of which the carbon black partial substitution by calcined kaolin would have better results and if it would be possible to obtain a composition that would last longer working under compressed conditions.The results shown that the best composition with a hybrid filler system is the F02: 35CB/15CC because it kept the mechanical reinforcement and had less modulus loss, which is fundamental for the artifact to maintain its properties for a longer time working under deformation. In a general way, as calcined kaolin substituted carbon black, the formulations presented less modulus, however, the amount of filler aggregates decreased considerably