Abstract
Characteristics of particles of thermo-sensitive gel in temperature-stratified polymer solution have been observed. Porous gel of N-isopropylacrylamide (NIPA) which generally has volumetric transition temperature around 32 ℃ in pure water was synthesized as porous medium and then covered by a layer of hydrophilic hydrogel. The rates of both particle-wall and inter-particles adhesion were decreased compared with those of gel particles without the outer layer. The particles in the polymer solution where temperature varied vertically between 10 to 40 ℃ periodically moved up and down at a period of about 15 minutes which is longer than that of particles without the outer layer.
