Synthesis of pH-sensitive water and oil dual-absorption material using microemulsion polymerization process

pH-sensitive water and oil dual-absorption material (WODAM) has been successfully synthesized through microemulsion polymerization. Firstly, microemulsions prepared with monomers were analyzed by pseudo-ternary phase diagram. In addition, conductivities of microemulsions were tested to identify microemulsion types. Meanwhile, the factors that affected microemulsion types were analyzed. Then WODAMs were prepared, and the chemical structure was characterized using Fourier transform infrared (FTIR) spectroscopy. Liquid absorption tests indicated that both monomer ratio and microstructure of WODAMs had influences on their water absorption rate (WAR) and oil absorption rate (OAR). In addition, pH sensitivity tests showed that WODAM absorbed much water in neutral and weak alkaline solutions, but little water in strong alkaline solutions. What's more, liquid absorption tests in cement slurry filtrate (CSF) showed that WODAM was applied to oil well cement. This paper prepared a new self-healing agent, and is of great significance to realize self-healing cement in complex downhole condition.