Ethylene glycol based silver nanoparticles synthesized by polyol process: Characterization and thermophysical profile

This study reports the synthesis and the characterization of ethylene glycol silver-based nanofluids produced from the polyol process. This synthesis process is based on the reduction of silver nitrate (AgNO3) with the presence of the aqueous emulsion of latex copolymer, used here for the first time along with ethylene glycol. The influence of latex copolymer content for a fixed amount of AgNO3 for the production of silver-based nanofluids is investigated. The efficiency of the synthesis process is demonstrated from UV-Vis spectrometry, TEM and EDS characterization of the nanofluids. In addition, the dynamic viscosity of both the base fluids and nanofluids is experimentally measured over a wide shear rate and temperature range. While the base fluids behave in a non-Newtonian manner due to the presence of copolymer nanoparticles, it appears that the nanofluids are simply Newtonian without any noticeable viscosity enhancement compared to pure ethylene glycol. The thermal conductivity of the produced ethylene glycol silver-based nanofluids shows an enhancement of about 3% for the higher initial contents in copolymer latex. Such a thermophysical profile of ethylene glycol silver-based nanofluids is promising for their potential applications as circulating heat transfer fluids. (C) 2020 Elsevier B.V. All rights reserved.