Development of self-healing cement slurry through the incorporation of dual-encapsulated polyacrylamide for the prevention ofwater ingress in oil well

Abstract

In the present work, a novel cross-linked polymer was synthesized though the anionic polymerization of cyanoacrylate with moisture as an initiator, methylene-bis-acrylamide as a cross-linker, and linseed oil as a spacer. Two layers of the synthesized polymer was coated over polyacrylamide for its homogenous impregnation in Class-G cement slurry for the synthesis of cement core. Fourier Transformation Infrared spectroscopy and X-Ray diffraction spectrum of the synthesized polymer and cement core were obtained to investigate the presence of different functional groups and phases. Moreover, the morphologies of the dual-encapsulated polyacrylamide was observed through scanning electron microscopy. Furthermore, the water-absorption capacity of the synthesized dual-encapsulated polyacrylamide in normal and saline conditions were tested. A cement core impregnated with 16% of dosage of dual-encapsulated polyacrylamide possesses an effective self-healing capability during the water-flow test. Moreover, the maximum linear expansion of the cement core was observed to be 26%. Thus, the impregnation of dual-encapsulated polyacrylamide in cement slurry can exhibit a superior self-healing behavior upon water absorption in an oil well.