Studying the Effect of Surfactant on Volume Phase Transition of Poly N-Isopropyl Acrylamide Microgels

Abstract

We have studied the effect of anionic surfactant Sodium Dodecyl Sulfate (SDS) on volume phase transition of Poly N-isopropyl Acrylamide (PNIPAM) Microgels. Three samples were prepared with different SDS concentration and studied with the help of Dynamic Light Scattering and UVVis Spectroscopy. A sharp volume-phase transition was observed for all the three samples as a function of temperature. A sharp decrease in microgel particle size was observed at 34 °C for SDS concentration of 1.05 mM. Decrease in particle size both in collapsed and swollen state is observed with increase in SDS concentration. With naked eyes the samples appears more turbid at room temperature for lesser SDS concentration, which has been confirmed with the help of UV-Vis measurements.