Abstract: The nonergodic behavior of κ-carrageenan(KC) thermoreversible gel was studied by static/dynamic light scattering (SLS/DLS). The speckle patterns, measured by SLS, appear in gel state of KC, which proves the nonergodic behavior of KC gel. Then the influences of temperature and concentration of KC solution on the nonergodic behavior were investigated. The results reveal that the nonergodic behavior of KC solution enhances with increasing of concentration, and weakens with increasing of temperature. Moreover, nonergodic behavior disappears when the temperature is higher than the one at which the transition from helix to coil conformation can be performed. The electrical field correlation function obtained by DLS shows that the gel state of KC possesses a power law behavior but the solution state of KC bears a stretched exponential behavior.

Key words: κ-carrageenan, Nonergodic behavior, Fluctuation