Original scientific paper

Monodisperse Sols of Barium Sulfate. I. Preparation of Stable Sols

J. Petres ; Department of Physical Chemistry, Institute »Ruder Boskovic«
Gj. Deželić ; Department of Applied Biochemistry, »Andrija Stampar« School of Public Health, Faculty of Medicine
B. Težak ; Laboratory of Physical Chemistry, Faculty of Science, University of Zagreb, Zagreb, Croatia, Yugoslavia

Abstract

Monodisperse sols of barium sulfate were prepared by a modified
method of homogeneous precipitation and characterized by
electron microscopy. The particles were spindle-shaped and of a
rather uniform distribution when prepared with concentrations of
barium and sulfate ions of 4 X 10·3 M. The degree of monodispersity
obtained depends on the cleanliness of solutions and glassware, and
good results were obtained by filtration of solutions and careful
cleaning of glassware. Morphological changes in the particles during
the reaction are studied. Monodisperse particles dispersed in the
mother liquor are not stable, since they aggregate and recrystallize
by aging. However, addition of nonionic detergents stabilizes the
particles for longer periods, as detected by electron microscopy
and ultramicroscopy. Stable sols of barium sulfate of particle size
from 195 to 480 mμ for the longer axis, and from 95 to 188 m~t for
the shorter axis, respectively, were prepared.

Keywords

Hrčak ID:

208146

URI

https://hrcak.srce.hr/208146

Publication date:

28.12.1966.

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