Magnetic orientation of nontronite clay in aqueous dispersions and its effect on water diffusion
Artikel i vetenskaplig tidskrift, 2015

The diffusion rate of water in dilute clay dispersions depends on particle concentration, size, shape, aggregation and water-particle interactions. As nontronite clay particles magnetically align parallel to the magnetic field, directional self-diffusion anisotropy can be created within such dispersion. Here we study water diffusion in exfoliated nontronite clay dispersions by diffusion NMR and time-dependant 1H-NMR-imaging profiles. The dispersion clay concentration was varied between 0.3 and 0.7 vol%. After magnetic alignment of the clay particles in these dispersions a maximum difference of 20% was measured between the parallel and perpendicular self-diffusion coefficients in the dispersion with 0.7 vol% clay. A method was developed to measure water diffusion within the dispersion in the absence of a magnetic field (random clay orientation) as this is not possible with standard diffusion NMR. However, no significant difference in self-diffusion coefficient between random and aligned dispersions could be observed.

Diffusion

Bound water

Diffusion NMR

Permeability

Exfoliated clay

NMR 1D imaging

Magnetic alignment

Nontronite clay

Anisotropic microstructure

Författare

Christoffer Abrahamsson

SuMo Biomaterials

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Lars Nordstierna

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Teknisk ytkemi

Matias Nordin

German Cancer Research Center

S. V. Dvinskikh

Kungliga Tekniska Högskolan (KTH)

Saint Petersburg State University - Spsu

Magnus Nydén

University of South Australia

Journal of Colloid and Interface Science

0021-9797 (ISSN)

Vol. 437 205-210

Ämneskategorier

Fysikalisk kemi

DOI

10.1016/j.jcis.2014.09.031