Temperature Effects In the Rheology of Soft Colloids

There has been a lot of interest recently in using colloids as model systems to understand glass transition; however the effect of temperature on the rheology of colloidal glasses is not clearly understood. We have investigated the effect of temperature on the dynamics of soft colloids. The model system we study is a new class of organic inorganic hybrid material consisting of polymer chain densely grafted to the nanoparticle surface. Termed nanoscale ionic materials (NIMs), these systems display fluid like properties in absence of any solvent and hence are termed ‘self suspended’ fluids. We find that contrary to polymer melts, increase in temperature slows down the dynamics of these materials. We believe this retardation is caused by increased interpenetration of the polymer chains with the increase in temperature.