Department of Physics, Kansas State University, Manhattan, KS 66506, USA.
Department of Physics, Kansas State University, Manhattan, KS 66506, USA.
J Colloid Interface Sci. 2019 Nov 15;556:577-583. doi: 10.1016/j.jcis.2019.08.075. Epub 2019 Aug 24.
We present investigations of the kinetics of the colloidal sol-to-gel transition by combining small angle static light scattering (SASLS) and dynamic light scattering (DLS) techniques. Dilute monomer volume fractions were used to allow for a full investigation of the gelation to obtain all possible kinetic regimes. Our data verify the predictions of a kinetic theory, the ideal gel point (IGP) theory, where three regimes of kinetics are expected. We observe the first regime, the well-known cluster-dilute regime, with a kinetic exponent of z = 1. Followed by a cluster-dense regime with an enhanced kinetics and z ≃ 2. Finally, a gelation regime is observed where the aggregate growth slows and ceases to grow at the IGP predicted size, R. These results quantitatively verify the IGP theory. We conclude that kinetic description provides a complete theory of the gelation process from sol to gel.
我们通过结合小角静态光散射 (SASLS) 和动态光散射 (DLS) 技术，对胶体溶胶到凝胶的转变动力学进行了研究。使用稀单体体积分数允许对凝胶化进行全面研究，以获得所有可能的动力学状态。我们的数据验证了动力学理论的预测，即理想凝胶点 (IGP) 理论，其中预计有三个动力学状态。我们观察到第一个状态，即众所周知的聚集体-稀溶液状态，动力学指数为 z=1。其次是聚集体-密溶液状态，动力学增强，z≈2。最后，观察到凝胶化状态，其中聚集体的生长速度减慢，并在 IGP 预测的尺寸 R 处停止生长。这些结果定量验证了 IGP 理论。我们得出结论，动力学描述为溶胶到凝胶的凝胶化过程提供了一个完整的理论。
