UV-Vis spectroscopy: UV-vis (Cary 60 UV-Vis, Agilent) spectroscopy was used to measure the absorbance of 20 mg/mL polymer solutions in a short path-length of 10 µm quartz cell (Starna Cells). Before each solution measurement, a blank solvent measurement was taken for background Freeze-drying method for imaging the solution-state aggregates: Freeze-drying experiments were conducted to image the structure of aggregates in solution by using microscopic techniques including Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The freeze-drying process involves rapid freezing of polymer solutions in liquid ethane and propane mixture (63% propane and 37% ethane) followed by liquid nitrogen storage. The purpose of using liquid ethane mixture is to ensure rapid freezing of the solution due to its large heat capacity and prevent polymer aggregation during the cooling process.