The law of a stretched exponential and the crossover of the behavior of a disordered nanoporous medium with a non-wetting liquid with its anomalously slow relaxation

Abstract

Relaxation of a disordered nanoporous medium filled with a nonwetting liquid is studied. An anomalously slow relaxation of the volume of the trapped liquid in such a medium is established, which is characterized by the law of a stretched exponential ∼exp[−(t/τ0)β]. At a temperature of Tc ≈ 280 K, a dispersion transition occurs, namely, the index β changes sharply from β > 0.4 at T < Tc to β < 0.3 at T > Tc. With such a transition, the non-wetting liquid becomes effectively wetting. An explanation for this crossover is proposed as the result of additional jamming of the liquid outflow from the porous medium due to the rupture of the percolation cluster of filled pores, over which liquid escapes.