Dynamic Disulfide Bond-Functionalized Self-Healing Resin Coatings for Surface Modification of Quartz Sand toward Sand Stabilization

Abstract

Coating failure of conventional resin-coated sand under harsh formation conditions can induce formation sand backflow, shorten the service life of sand-control systems, and ultimately impair oil and gas well productivity. In this study, a self-healing epoxy resin with a dynamically reversible disulfide-bond network was synthesized and applied as a surface coating to prepare self-healing resin-coated sand for fracture-packing sand control. The self-healing epoxy resin exhibits excellent self-healing capability, achieving up to 86.15% healing efficiency within the temperature range of 80–100 °C. The prepared SHCS exhibited high fracture conductivity, in situ self-healing capability, and sand-binding performance. Through dynamic disulfide exchange, detached SHCS particles can be recemented and self-healed, achieving a healing efficiency of up to 82.41%. Moreover, attributed to the fine-sand capture and aggregation capability of the self-healing coating, SHCS effectively controlled the sand production rate below 0.05 g/L, significantly extending the service life of sand control systems. This work demonstrates the potential of self-healing coatings for the modification of resin-coated sand and provides a promising strategy for the application of self-healing coatings in oil and gas exploitation.