Shedding Light on the Role of Short-Chain Alcohols in Amphiphilic Polymer Assembly: Implications for Oil and Gas Recovery Operations

Abstract

In this work, we investigated the supramolecular organization of self-assembled poly(LMA-co-PEGMA) structures in aqueous solution in the presence of short-chain alcohols, focusing on their compartmentalization between molecular aggregates and the bulk aqueous phase, as well as their implications for polymer-based methods in enhanced oil recovery. Polymers were synthesized using reversible addition–fragmentation chain transfer polymerization and characterized by nuclear magnetic resonance and size exclusion chromatography coupled with multi-angle light scattering and differential refractive index detectors. Dynamic light scattering revealed differences in the supramolecular organization of self-assembled aggregates in the presence of short-chain alcohols, reflected by changes in the aggregation number and critical aggregation concentrations. Additionally, fluorescence-based experiments were carried out to characterize compartment properties within the aggregates─such as polarity and microviscosity─and the influence of spatial organization and conformation. Moreover, we used nuclear Overhauser effect spectroscopy and inversion recovery experiments to gain deeper insight into monomer–alcohol and copolymer–alcohol interaction and dynamics. Finally, oil transfer experiments reflected the effect of short-chain alcohols on the solubilization process. The obtained results allowed us to propose a cooperative mechanism that explained the aggregation behavior observed for different alcohols and its effects on oil solubility, a key factor considering applications related to enhanced oil recovery.