Synthesis and Properties of a Low-Viscosity and Acid-Resistant Retarding Agent

In order to enhance the acid resistance and injection ability of retarded acid and to achieve a deep acidification, a low-viscosity acid-resistant retarding agent (LVAR) was synthesized via radical aqueous polymerization using 2-acrylamido-2-methyl-1-propanesulfonicacid (AMPS), [2-(methacryloyloxy)ethyl] trimethylammonium chloride (DMC), and N,N′-dimethyl hexadecyl allyl ammonium chloride (C₁₆DMAAC) as monomers. The acid, temperature, and salt resistance of LVAR, as well as its retardation and compatibility characteristics were analyzed using viscometer, scanning electron microscope, and the acid rock dissolution experiment. The results showed that the viscosity of a 1.0% LVAR-retarded acid solution was only 4.5 mPa s, which represented a low-viscosity effect. After 4 h of incubation at high temperature (90°C), LVAR-retarded acid remained clear and transparent, and showed good acid resistance. The corrosion rate of 1.0% retarded acid solution at 35 and 95°C was 37.4 and 71.2%, respectively, indicating a good retardation performance. These findings may provide new insights for the study of low-viscosity and acid-resistant retarding agents.