Gelation Process and the Scattering Intensity of Chemical Gels through Simulation of an Aggregation Model with Mixed Functionalities

Abstract

We study gelation process of chemical gels through simulation of a cluster–cluster-aggregation (CCA) model, and discuss the time development of scattering intensity I(q). With respect to the functionality of monomers, we consider two cases: the four-functional case in which all monomers have four bonds, and the mixed-functional case in which monomers with two bonds and four bonds coexist on the lattice. The structures of gels are quite different for the four-functional and mixed-functional cases. Furthermore, clusters grow faster for the four-functional case than for the mixed-functional case, with a given initial concentration investigated. However, the scattering profiles and their time evolutions are similar for the two cases. At the final stage, the peak intensity of the four-functional case is larger than that of the mixed-functional case, which should be consistent with experiments on speckle patterns.