高于胶凝临界温度的明胶水溶液弛豫谱研究

Relaxation Spectrum of Aqueous Gelation Solution above Critical Temperature of Gelatification

在高于胶凝临界温度条件下，半稀明胶水溶液的动态光散射弛豫谱存在三段弛豫过程，即弛豫时间小于５０μｓ的指数衰减过程、幂律衰减过程和伸展指数衰减过程．后两个过程可归因于分形构象的反常扩散，其方均位移分别为〈Ｒ２〉∽ｌｎｔ和〈Ｒ２〉∽ｔβ（β＜１），宽度参数与明胶分子分数维和分形子谱维数有关．

Above critical temperature of gelatification, the evolution of relaxation of dynamic light scattering on semidiluted aqueous gelatin solution covers three relaxation processes. The first one is characterized by exponential decay, with a relaxation time less than 50 μs; the second one, by power law decay; and the last one, by stretched exponential decay. The latter two may be attributed to the anomalous diffusion of fractal conformation, with 〈R2〉∽lnt and 〈R2〉∽tβ(β<1) as their respective mean square displacement. Parameter of width has a bearing on the fractal dimension of gelation molecule and the spectral dimension of fracton.