Synthesis and characterization of novel acrylamide-based ternary polyampholyte as tracer agent

Abstract

A novel ternary polyampholyte composed of fully charged anionic monomer – 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt (AMPS), cationic monomer – (3-acrylamidopropyl) trimethylammonium chloride (APTAC) and the positively charged fluorescent dye – acrylamide Nile Blue (ANB) was synthesized by conventional free radical copolymerization and characterized by FTIR, UV-Vis, fluorescence spectroscopy, dynamic light scattering and zeta-potential. FTIR spectrum of AMPS-APTAC-ANB shows that introduction of 1 mol.% ANB into copolymer composition does not influence the basic characteristic bands of polyampholyte. The adsorption and emission peaks of AMPS-APTAC-ANB found at l_max = 586 nm and l_max = 660-680 nm are attributed to ANB groups of terpolymer. The average hydrodynamic size and zeta potential of AMPS-APTAC-ANB in aqueous solution that are equal to 4.3 nm and x= -1.6 mV indicating the globular conformation of amphoteric macromolecules with a slightly negative charge. Injection of 0.1 wt.% (or 1.3×10^-3 mol×L^-1) AMPS-APTAC-ANB into the core sample derived from the “Vostochnyi Moldabek” oilfield demonstrated the passing of fluorescently-labeled terpolymer through the core. The ternary polyampholyte containing the fluorescent marker can serve as oilfield tracer for monitoring well-to-well connections (or interwell tracer test).