Measuring LCSTs by novel temperature gradient methods: evidence for intermolecular interactions in mixed polymer solutions.

Herein we describe studies of molecular interactions in thermoresponsive polymers as they go through phase transitions in aqueous solutions. By using our recently reported linear temperature gradient setup for studying the effects of temperature on chemical processes, we demonstrate the ability to probe lower critical solution temperature (LCST) behavior with excellent precision. This method also provides a simple and convenient way to assay the LCST of solutions containing more than one polymer and follow the clouding kinetics of polymer mixtures in real time.