Development and Characterization of CO₂-Responsive Intelligent Polymer Sealant

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Underground geological storage is crucial for Carbon Capture, Utilization, and Storage (CCUS).
• Effective mitigation of CO2 leakage is essential for the safety and success of CCUS operations.
• Development of advanced sealing materials is needed to prevent CO2 migration.

Purpose of the Study:

• To develop and characterize an innovative intelligent polymer sealant for mitigating CO2 leakage in geological storage.
• To investigate the properties and performance of a CO2-responsive polymer system cross-linked with polyethylenimine (PEI).
• To evaluate the sealing efficiency and migration performance of the developed gel sealant.

Main Methods:

• Formulation of a CO2-responsive polymer sealant using acrylamide (AM) and N-[3-(dimethylamino) propyl] methacrylamide (DMAPMA) cross-linked with PEI.
• Systematic investigation of sealant characteristics including rheological properties, thermal behavior, conductivity, and microstructures.
• Core fluid displacement experiments to assess CO2 and water sealing efficiency.

Main Results:

• The polymer sealant demonstrated excellent injectability, rapid response, thermal stability, and mechanical strength.
• Upon CO2 exposure, the sealant transitioned from sol to gel, forming a stable 3D network structure.
• Achieved 73.6% CO2 sealing efficiency and 96.2% subsequent injection water sealing rate.

Conclusions:

• The developed CO2-responsive gel sealant shows exceptional potential for CCUS applications.
• This innovation offers a novel strategy to enhance CO2 leakage mitigation in geological storage.
• The study contributes to advancing the effectiveness of CO2-responsive gel sealants for safer CCUS operations.