Preparation and performance evaluation of low-temperature steerable fracturing temporary plugging agent

To overcome the limitations of traditional gels in low-temperature refracturing applications, a novel low-temperature self-degrading gel (LT-SDG) was developed. The gel is based on an acrylamide–acrylic acid copolymer crosslinked with SEG and initiated by a thermal APS/SHS system. It forms a robust 3D network at 35–40 °C and degrades spontaneously without external breakers. The formulation was optimized by investigating the effects of monomer concentration, crosslinker content, initiator ratio, and neutralization degree on gelation, strength, and degradation. Structural and thermal properties were characterized via FTIR, DSC, and SEM. Experimental results demonstrated that the optimized LT-SDG achieves gelation within 1.5–3 h, reaches a strength grade of H–I, and degrades into a low-viscosity fluid within 200–500 h. Mineralization tests showed that Na + accelerated degradation via charge shielding, while Ca 2+ enhanced network stability through ionic crosslinking. Sand-packed tube and core flooding experiments confirmed excellent plugging performance (>99.5 %) and high pressure-bearing capacity, with permeability recovery reaching 93.77 % after full degradation. Moreover, LT-SDG exhibited good compatibility with guar-based fluids and slickwater, ensuring stable performance under field conditions. These results indicate that LT-SDG provides clean, efficient, and controllable zonal isolation in low-temperature reservoirs, offering a promising solution for diversion fracturing in mature wells.