Croatica Chemica Acta, Vol. 52 No. 2, 1979.
Conference paper
The Structure of Polyvinyl Alcohol Adsorption Layers at Interfaces with Benzene in Connection with Stability of Concentrated Emulsions
V. N. Izmailova
; Department of Co!loida.l Chemistry, Moscow State University, Leninsky Gory, Moscow, USSR
G. M. Pismennaya
; Department of Co!loida.l Chemistry, Moscow State University, Leninsky Gory, Moscow, USSR
T. F. Busol
; Department of Co!loida.l Chemistry, Moscow State University, Leninsky Gory, Moscow, USSR
B. N. Tarasevich
; Department of Co!loida.l Chemistry, Moscow State University, Leninsky Gory, Moscow, USSR
Abstract
Determination of PV A adsorbtion on interfaces between PV A
and benzene was performed. Adsorbed layers are formed under
dynamic conditions emulsions were prepared by vibrocomminution
and ultrasonic dispergation). Adsorbtion data are used in calculation
of the area per adsorbed molecule and the thickness of interfacial
adsorpbtion layers. Adsorption isotherms are compared with rheological
parameters of adsorbed layers. On the basis of reported data
on the distribution of adsorbed segments of PV A molecules, the
interfacial thickness of the adsorbed layer is estimated to be several
hundreds of A in a fo rm of gel. The formation of the gel is a result
of condensation and phase deemulgation which is in agreement with
a similar mechanism of gel formation in solution with diffuse
distribution of polymer segments in the adsorbed layer. It is shown
that at least one monolayer must cover drops of benzene in order
to obtain stable emulsions. Kinetic parameters and the energy of
activation of coalescence are dependent on PV A adsorption.
Keywords
Hrčak ID:
195903
URI
Publication date:
25.6.1979.
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