Thermoresponsive redispersible polystyrene latexes

Polystyrene (PS) latexes prepared using low-molecular-weight amphiphilic thermoresponsive surfactants exhibited reversible coagulation. The prepared low molecular surfactant exhibited thermal transition at concentration above their critical micellar concentration (CMC). Latexes prepared with surfactant containing thermoresponsive segments, i.e., surfactants with poly(2-ethyloxazoline) resulted in white coagulant above its LCST at 85 oC and redispersed upon cooling to room temperature, while latexes prepared with non-responsive units remain unresponsive to change in temperature. Comparison of the particle sizes of the pristine and redispersed latex at 25 oC exhibited nearly identical size and shape, before and after heating up to 85 oC that effected coagulation. The re-dispersibility of the coagulated polystyrene latexes allows to mitigate energy consumption in the design and synthesis of such latexes used in many day-to-day applications.