κ-卡拉胶热可逆凝胶的非遍历行为研究

采用散射斑纹(speckle)技术, 即散射光强涨落法, 研究了κ-卡拉胶(KC)热可逆凝胶的非遍历行为. 证明了非遍历性的存在, 并研究了浓度、温度等条件对该非遍历性的影响. 结果表明：该物理凝胶存在非遍历性, 并随KC浓度增加, 凝胶非遍历性增大；随温度升高, 凝胶非遍历性逐渐减小, 直至消失.

A Study on the Nonergodic Behavior of k-carrageenan Thermoreversible Gel by Static and Dynamic Light Scattering

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.