Influence of Alkyl Chain Length on the Performance of Inverse Emulsion Polyacrylamide Fracturing Fluid Thickeners

Abstract

The alkyl chain length of hydrophobic monomers significantly influences the properties of hydrophobic associative polymers. In this study, four hydrophobic monomers with varying chain lengths were copolymerized with acrylamide, using the inverse emulsion polymerization method. Four hydrophobic associative polyacrylamides were successfully synthesized and characterized using infrared spectroscopy, nuclear magnetic resonance (NMR), and radius of gyration detection, and they were compared with polyacrylamides (PAMs) (without hydrophobic monomers). Polymer morphology was analyzed using scanning electron microscopy, while rheological properties were assessed using a rheometer. Emulsion stability was determined by measuring conductivity. Investigation indicate a direct correlation between the rheological properties of the polymer and the stability of the emulsion with the alkyl chain length of the hydrophobic monomer. The longer the alkyl chain of the hydrophobic monomer, the higher the rheology and emulsion stability of the polymer by increasing hydrophobic association and droplet encapsulation.