Environmental Engineering Reference
In-Depth Information
signi
cantly increase the amount of oxidizers, such as hydrazine nitrate, dissolved
in fatty amine, and water played a cosolvent (or solubilizer) role. When solute
components of the liquid explosive cannot be completely dissolved in the solvent, a
variety of substances with similar properties can be considered to increase their total
dissolving amount in the solvent. As proved in experiments, when a sensitizer
explosive (e.g., TNT) is dissolved in nitromethane, it does not affect the dissolution
of other ingredients (such as RDX, PETN), which means every nitro compound
sensitizer can reach its own solubility without affecting each other in nitromethane.
3.3.2 Liquid Explosives with Small Solid Particles [
8
]
Suspension systems of sticky slurry and paste-like liquid explosives with solid
particles, based on the dispersion of suspended solid particles, should belong to
suspension or coarse multiphase systems in colloid chemistry. In these suspension
systems, the main issue is its dynamic instability, because the density of the dis-
persed particles and the density of the dispersion medium are different (generally,
the density particle is greater than that of the medium), settlement or
fl
floating can
occur with the role of gravitational
field to separate the system, resulting in
unevenness in composition and density of liquid explosive. Stability is the ability to
overcome the so-called sink-and-
oat separation of two-phase components, there-
fore, within a certain period of use, the composition and density of explosive and
other physical parameters remained unchanged and its properties are stable and
reliable.
Here, the method of increasing the viscosity of the suspension system to reduce
settling velocity of suspended particles will be mainly discussed. The general
method to increase the viscosity of suspending medium is to add tacki
fl
er. There are
two types of tacki
ers: (1) polymer and (2) some ultra
ne inorganic materials, such
as carbon black, silica, alumina, etc. Polymer tacki
er is usually dissolved in the
suspension medium, and polymer concentration is adjusted to achieve the desired
viscosity and their roles are generally based on their dissolving or swelling in the
liquid medium. Roles of ultra
ne inorganic materials are based on the interaction
between their huge surface areas and the liquid medium, and suspension systems
with these dispersions usually have thixotropy and abnormal viscosity.
g ¼ g
0
þ g
00
ð
3
:
28
Þ
g
00
is structure viscosity, which can disappear due to
the tangential stress changes or mechanical action. Advantages of this tacki
g
0
wherein
is Newton viscosity,
er is to
lead to a relatively high viscosity of the system at a static status, which is very
conducive to the stability of suspension system; and the dynamic viscosity is not
high, which does not affect the
fl
flow and transport of the material system. Therefore,
this tacki
er is often used in liquid explosive recipes. Most of tacki
ers are inert,
