The pH and Temperature Dual-Switchable Polymer Emulsion via Acid-Based Ionic Liquid with Ultrasensitive Releasing for...

Area of Science:

• Chemical Engineering
• Materials Science
• Polymer Chemistry

Background:

• Hydraulic fracturing requires fast-dissolving polyacrylamide drag reducers for efficient shale oil and gas extraction.
• Current drag reducers face challenges due to rapid injection processes demanding quicker dissolution rates.

Purpose of the Study:

• To synthesize ionic liquids (ILs) from fatty acids and alcohol amines as switchable emulsifiers.
• To develop pH- and temperature-responsive polymer emulsions for enhanced drag reduction.
• To improve the dissolution rate of drag reducers in hydraulic fracturing fluids.

Main Methods:

• Inverse emulsion polymerization using a W/O switch monomer emulsion of acrylamide (AM), acrylic acid (AA), and 2-acrylamide-2-methylpropanesulfonic acid (AMPS).
• Utilized pH- and temperature-responsive interface switch mechanisms for controlled polymer release.
• Incorporated ethoxy (EO) chains into emulsifier headgroups for temperature responsiveness.

Main Results:

• Achieved a rapid dissolution rate of only 20 seconds for the switchable polymer emulsion drag reducer at pH 9.
• Demonstrated high drag-reduction rates of 74.93% in clear water and 73.78% in standard brine with 0.05 wt % concentration.
• Molecular dynamics simulations provided insights into polymer emulsion interactions and release mechanisms.

Conclusions:

• The developed switchable polymer emulsion drag reducer offers a significant advancement in hydraulic fracturing fluid technology.
• The rapid dissolution and high drag-reduction efficiency address key challenges in shale oil and gas extraction.
• The pH- and temperature-responsive nature allows for tunable performance in various downhole conditions.