For the last two decades, many polymers have been tested to increase CO2 viscosity for enhanced oil recovery. Unfortunately, HC-polymers were found to be inactive for the viscosity enhancement due to their poor solubility in supercritical CO2 (scCO2). A recent SANS study (RB1610015) found that unusual FC-HC amphiphiles without a “headgroup” formed HC-core/FC-shell cylindrical aggregates in scCO2. The elongated aggregates can play an important role to enhance solubility of HC-polymers in scCO2 and to advance the polymer 3D-network by wrapping and conjugating the polymers with HC-HC interaction and/or specific interactions like hydrogen bond. This proposal aims to find appropriate HC-polymer/FC-HC amphiphile mixtures for constructing 3D-network in scCO2. This SANS study will provide important information and enable the development of novel, EOR-oriented, CO2-thickeners.