Constitutionally Dynamic Oil Well Construction Fluids – Metallo-aminal Chemistry

Completion fluids which are designed to build viscosity or form reversible gels suffer from performance limitations due to thermal degradation of the fluids at the high temperature conditions of many oil and gas wells. The hemiaminal/aminal metallogel system reported in this paper demonstrates the possibility of performance without degradation at temperatures up to 150 degrees C and pressures up to 60 MPa. The chemical system is also demonstrated to be reversible under stimulated well conditions whereby the thermodynamically favored metallogel can be broken within a sandstone core sample pressurized at 3.4 MPa and held at 70 degrees C. These findings demonstrate the suitability of this reversibly covalent chemical system as a high-performance completion fluid for such operations as perforations and workovers.