Environmental Engineering Reference
In-Depth Information
5.5.2 Property and Preparation of Polyethenol Nitrate [
3
]
Polyethenol nitrate (nitro polyethenol) is a synthetic polymer to replace cellulose
nitrate. It was
first studied in 1929. Polyethenol was dissolved into concentrated
sulfuric acid at 0
°
C. The solution was then slowly added to a mixed acid of nitric
acid and sulfuric acid and gradually heated to 40
50
°
C. Polyethenol nitrate was
-
precipitated out. The plastic precipitate was then
filtered and washed to become
fragile products with a nitrogen content of 10 %. In the nitration of polyethenol in
10
C, polyethenol is easy to be oxidized. Thus, the oxidation should be pre-
vented by some methods.
Hydroxyl groups of polyethenol cannot be completely esteri
20
°
-
ed whatever in the
mixed acid of nitric acid
sulfuric acid or nitric acid
acetic acid because of the
-
-
cohydrolysis. It is nitrated by a mixture of nitric acid
acetic acid or a nitric acid
-
carbon tetrachloride solution. The high nitrated product can be softened at
40
-
50
°
C. The lead-block value of polyethenol nitrate with a nitrogen content of
-
13
342 cm.
The nitrogen content of polyethenol nitrate is generally in a range of 13.5
15 % is 153
-
-
-
14.5 %, while the theoretical maximum nitrogen content is 15.75 %. The detonation
velocity of polyethenol nitrate is similar with cellulose nitrate, which has the same
nitrogen content as polyethenol nitrate. The detonation velocity of polyethenol
nitrate with a nitrogen content of 13.4 % in a paper cylinder with a diameter of
30 mm is shown below.
Loading density of 0.3 g/cm 2,030 m/s
Loading density of 0.6 g/cm 3,450
-
3,520 m/s
Loading density of 1.0 g/cm 4,920
5,020 m/s
Loading density of 1.4 g/cm 6,090 m/s
Loading density of 1.5 g/cm 6,560 m/s
Polyethenol nitrate is
-
flammable and infusible. It has not been used in industry
because of its poor chemical stability. Different from cellulose nitrate, which can be
existed as a solution and be a highly mechanical film after evaporation of the
solution, polyethenol nitrate cannot be formed as a solution. It might be because of
the shortage of oriented molecular chains.
fl
5.5.3 Property and Preparation of Diglycerine Tetranitrate
5.5.3.1 Property of Diglycerine Tetranitrate
Diglycerine tetranitrate, shortly called nitro diglycerine, can be prepared by nitra-
tion of diglycerine.
