FURI | Spring 2023

Lower Critical Solution Temperatures of PEG-PPG Polyurethanes

Polyurethane polymers are synthetic plastics that are slowly increasing their applications in biological systems such as drug delivery. When polyethylene glycol (PEG) and polypropylene glycol (PPG) are combined, the resulting PEG-PPG polyurethane has shown swelling transitions in response to varying external temperatures. This research focuses on identifying the temperature, known as the lower critical solution temperature (LCST), where the PEG-polyurethanes undergo a transition in swelling when raised from room temperature to normal body temperature (25ºC to 39ºC). Different ratios of the PEG to the PPG may affect the temperature where this transition occurs.