Over the last two decades, many polymers have been tested to increase CO2 viscosity for applications in enhanced oil recovery using CO2 (CO2-EOR). Unfortunately, conventional HC-polymers were inactive for viscosity enhancements due to their poor solubility in supercritical CO2 (scCO2). Recent SANS studies (RB1720361, RB1820137) found that tailor-made CO2-philic/ CO2-phobic amphiphiles formed rod-like aggregates (RAs) encapsulating HC-polymers in scCO2. The length of RAs was strongly dependent on both the architectures and concentrations of the amphiphiles and HC-polymers. To develop inexpensive, environmental-friendly and effective HC-polymer-based CO2-thickners for CO2-EOR, this experiment will explore optimum structures, concentrations, and compositions of amphiphiles, cross-linkers and HC-polymers to generate 3D-structured networks of RAs with HC-polymer backbones in scCO2.