The 9th International Conference on Multiscale Materials Modeling

講演情報

Poster Session

M. Time- and History-Dependent Material Properties

[PO-M1] Poster Session 1

Symposium M

2018年10月29日(月) 17:45 〜 20:00 Poster Hall

[P1-69] FORMATION OF PHYSICAL GELS BY ARRESTED SPINODAL DECOMPOSITION IN CHARGED COLLOIDS

Jose Manuel Olais-Govea1, Alonso Gomez-Canales1, Leticia Lopez-Flores2, Martin Chavez-Paez2, Magdaleno Medina-Noyola2 (1.Instituto Tecnologico y de Estudios Superiores de Monterrey, Mexico, 2.Universidad Autonoma de San Luis Potosi, Mexico)

The general understanding of gelation processes is recognized as a major challenge in soft matter field. Particularly, attractive liquids that suffer a suddenly instantaneous isochoric quench an homogeneous state to thermodynamic instability could form a physical gel. Although, both experimental and simulation advances in understanding gelation phenomenon had led to build a general comprehension about physical gel properties and even had discussed the perform of novel materials as amorphous solids, there is no a clear theoretical approach to explain these class of ubiquitous materials. In recent work, however, the general theory referred to as the non-equilibrium self-consistent generalized Langevin equation (NESCGLE) theory, based on a non-equilibrium extension of Onsager’s canonical theory of thermal fluctuations, was adequately adapted to describe memory effects, protocol-dependent preparation and irreversible aging processes associated with the glass and the gel transitions in attractive simple liquids. In particular, this theory was capable of predict a glass-glass transition line and propose a glass-gel line in a monocomponent attractive Yukawa simple fluid (HSAY) by arested spinodal decomposition when that system is instantaneously quenched inside spinodal region. In the present work, we extend this analisys in the context of a very specific model system, namely, let us consider an screened restricted primitive model (YRPM), represented as an electroneutral mixture of charged hard spheres embedded in a dielectric medium of uniform dielectric constant. Additionaly we show pertinent comparisons between our theoretical results and the gel formation in a mixture of equally-sized oppositely charged colloids both experimentally and by means of computer simulations.