Research on Novel Phase‐Change Fracturing Fluids Based on High‐Strength Modified Resins

ABSTRACT Traditional hydraulic fracturing technology suffers from low proppant efficiency and significant formation damage due to its reliance on high‐viscosity fluids. While phase‐change fracturing fluids overcome these issues by generating proppants in situ through liquid injection and formation‐triggered phase transformation, existing systems still face challenges such as inadequate proppant strength and poorly defined interfacial control mechanisms. This study aims to develop a novel phase‐change fracturing fluid system (MPCF) with enhanced strength, minimal reservoir damage, and high conductivity through molecular design and interfacial engineering. By introducing dicyclopentadiene (DCPD) into unsaturated polyester resin, a high‐strength functional monomer (PGC1) was synthesized, increasing its compressive strength from 42 to 95 MPa. The optimal MPCF formulation was established alongside an ideal interfacial tension range of 3.2–4.5 mN/m. Under these conditions, the resulting phase‐change proppant (MP) exhibits excellent comprehensive performance: sphericity of 0.9, breakage rate of only 1.5% at 60 MPa, and acid solubility as low as 0.18%. Flow capacity tests confirmed that MP outperforms conventional proppants across the 0–60 MPa closure pressure range. This work provides both a theoretical framework and a practical solution for improving proppant placement and fracture sustainability in unconventional reservoirs.