@article{Wang2026, 
author = {Quan-De Wang and Guan-Cheng Jiang and Teng-Fei Dong and Sheng-Ming Huang and Yin-Bo He and Li-Li Yang and Qi Feng and Hua-Yan Mu},
title = {A novel ultra-high-temperature emulsifier stable at 250 ℃ for oil-based drilling fluids: Synthesis, performance, and mechanism},
year = {2026},
journal = {Petroleum Science},
volume = {23},
number = {9},
pages = {5648-5661},
keywords = {Exploration, Emulsifier, Temperature resistance, Mechanism},
url = {https://www.sciopen.com/article/10.1016/j.petsci.2026.04.009},
doi = {10.1016/j.petsci.2026.04.009},
abstract = {The ultra-high temperature conditions encountered in deep oil and gas exploration represent a critical challenge to oil-based drilling fluid (OBDF) technology. Conventional emulsifiers suffer from rapid deterioration of interfacial stability under harsh environments exceeding 200 ℃, significantly increasing the risk of emulsion breakdown and creating a critical bottleneck for ultra-high temperature drilling operations. To address this challenge, this study aimed to develop a novel high-efficiency ultra-high temperature emulsifier (UHT-EM). The UHT-EM was successfully synthesized via a three-step method, and its molecular structure and excellent thermal stability were confirmed by Fourier-Transform Infrared Spectroscopy (FT-IR) and Thermogravimetric Analysis (TGA). The key synthesis process was optimized using response surface methodology, establishing optimal conditions (molar ratio 1.8, temperature 53 ℃, catalyst dosage 13.4%) with an actual yield of 85.23%. Performance evaluation demonstrated that UHT-EM significantly reduced oil-water interfacial tension. At a dosage of 1.0%, the emulsion maintained optimal rheological properties and electrical stability (ES &gt; 1400 V) after thermal aging at 230 ℃. Systematic temperature resistance tests revealed that the UHT-EM system maintained structural stability at 250 ℃, while experiencing sharp performance deterioration at 260 ℃ due to interfacial film disruption. Microscopic analysis revealed that stabilization mechanism arose from a dense interfacial adsorption layer, while interface failure was caused by intensified molecular thermal motion under high-temperature conditions. The innovation of this research lay in developing a novel emulsifier with well-defined temperature resistance and revealing its stabilization and failure mechanisms through multi-scale analysis, providing crucial material support and theoretical foundation for ultra-high temperature drilling fluid design.}
}