Rheological Additives for Crop Protection - Elementis Specialties

ELEMENTIS SPECIALTIES Rheological Additives
N N oo o o nn n n - - A A qq q q uu u u ee e e oo o o uu u u s s -
-
Phase Phase Thickeners
Thickeners
Fig 5
8
Vegetable oils and solvents need
different approaches to achieve
suspension and flow control. The choice
BENTONE ® Organophilic Organophilic Clays
Clays
Clay (hectorite or bentonite) is reacted
with quaternary ammonium compounds
to produce organophilic clays. The
choice of clay and quaternary
ammonium compound determines the
degree of dispersibility and, more
importantly, the organoclay activity. For
example, BENTONE ® 34 and
BENTONE ® 38 additives are designed
for gelling medium- low polarity organic
liquids. Whereas BENTONE ® 27
additive is suitable for higher polarities.
is between organoclay or polymer based
thickeners.
The advantages gained from using
BENTONE ® organoclays are:
- Thermostable viscosity control
- Thixotropy
- Suspension control of actives
- Emulsion stabilisation
The presence of surfactants should be
avoided at the dispersion stage. Correct
incorporation (Fig 6) requires the use of
high-shear dispersion equipment and the
addition of a chemical activator.
However, easy-dispersing BENTONE
SD ® rheological additives, which do not
require activation, are also available.