Critical Kinetics of Volume Phase Transition of Gels

The volume phase transition of submillimeter spherical isopropylacrylamide gels shows critical kinetic behavior near the critical point; the transition takes an infinite time, and the thermal expansion becomes infinitely large. At the critical point the gels also undergo internal critical density fluctuations as revealed by photon-correlation spectroscopy. The observation of critical kinetics along with critical dynamics clarifies the physical principle of the kinetics of gel volume change.