Síntese de Amidas Graxas e sua Aplicabilidade como Modificadores Reológicos em Fluidos de Perfuração Não-Aquosos

Abstract

This work aimed to obtain and characterize fatty amide chains and evaluate their potential application in non-aqueous drilling fluids as rheological modifiers. The products were obtained from the reaction between fatty acid dimer and diethylenetriamine, via carbodiimide coupling. The materials were characterized by infrared (IR) spectroscopy, visual stability test, dynamic light scattering (DLS) and rheological measurements. The drilling fluid containing one of the synthesized products was evaluated through viscosity measurements, filtration at high temperature and high pressure (HTHP) and electrical stability. The IR spectra of the derivatives showed amide bands, proving that there was an amidation reaction. Through the visual stability test it was observed that fatty amides, unlike the acid precursor, were insoluble in water. Through the DLS measurements it was possible to observed that longer the reaction time, larger the particle sizes. The rheological measurements also corroborated with DLS data and viscosity of the fatty amides was higher as the reactions time increased. Tests in drilling fluid showed that presence of fatty amide increased fluid viscosity values, decreased HTHP filtrate volume value and presented electrical stability value within acceptable standards established by the industry.