Post on 19-Mar-2018
Physical Sciences Inc. 20 New England Business Center Andover, MA 01810
VG07-159
Novel Plasticizer for IM Compliant Solid Propellants
Ana Racoveanu and LaShadric C. GradyPhysical Sciences Inc.
Scott K. DawleyAerojet
Disclaimer:
"The views, opinions, and findings contained in this report are those of the author(s) and should not be construed as an official Department of Defense position, policy, or decision.“
Acknowledgement of Support and Disclaimer
This material is based upon work supported by the Missile Defense Agency under Contract Number HQ0006-07-C-7629. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Missile Defense Agency.
Distribution Statement A. Approved for public release; distribution is unlimited.
Approved for Public Release07-MDA-2784 (5 SEPT 07)
VG07-159-1
Physical Sciences Inc.
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35 year-old company of 175 talented scientists, and engineers
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We work in headquarters in Andover, MA, with five satellite locations in the United States
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Acoustics
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Electro-magnetics
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Fluid physics
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Life sciences
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Chemical sciences
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Energetic Materials
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Optical sciences
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Plasma physics
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Space physics
VG07-159-2
NF1 Plasticizer Background
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NF1 was identified through modeling and literature data as an insensitive propellant ingredient
- NF1 will be a liquid at room temperature
- Potential High Density
- Improved properties over Butyl NENA
- IM Capability
VG07-159-3
NF1 Background (Cont’d)
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PSI synthesized and characterized (FT-IR, NMR, Elemental Analysis, GC-MS) NF1 – Low cost precursors– 30% overall yield (not optimized)
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Aerojet performed the energetic and thermal properties testing
VG07-159-4
NF1 Structure
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Structure: Nitro-furazan derivative
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Attributes: - only one nitro group: insensitive- heterocyclic ring: good density
NO
N
RO2N
MF plasticizer
NCH2
H2C
CH2
CH3H2C
O2NO
NO2
Butyl NENA plasticizer
butyl groupnitramine group
nitrato group
CH2
nitrofurazan ringorganic group
VG07-159-5
NF1 Properties
NF1 a promising plasticizer with good energy and good density
DensityGm/cc
DecompositionTemperature,
ºCΔHf,
Kcal/molNF1 theor 1.620 180 69.5
NF1 exp. 1.467 180 58.8
Butyl NENA 1.211 165 -45.55
TMETN 1.488 158 -105.8
BTTN 1.520 154 -92.6
VG07-159-6
IM Propellant Approach
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HTPB propellants exhibit violent cook-off response– Decomposition occurs through ammonium perchlorate decomposition– Decomposed AP reacts quickly and violently
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Energetic additive can reduce AP decomposition violence– Butyl NENA based HTPE formulations generally benign
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NF1 can be used as an energetic additive– Reduced energetic groups compared to other additives– Energy stored in furazan ring structure– Good density due to compact furazan ring
NF1 used as a plasticizer:Propellant IM Compliance is expected to increase
VG07-159-7
NF1 Sensitivity
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NF1 properties– Low viscosity fluid
– Moderate volatility
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Measurements show it is insensitive– Category “Green” [normal]
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Insensitive in shock tests– Negative at zero cards
Hazard NF1 RDX
Impact, kg-cm 145 49Friction, psi @ drop angle, o 1800 @ 90o 1200@90o
ESD, J @ 5kv 6.0 0.38
Negative at highest settings of test instruments
VG07-159-8
NF1 Shock Test
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Measures shock sensitivity of material
– Calibrated to identify threshold sensitivity level
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Results:
Material does not detonate even at zero cards
Sample Loading
Results - Insensitive
VG07-159-9
NF1 Density
Density measured to be 1.467 gm/cc (corrected)
MFNO D.I. H20
g/cc g/cc
1.4820 1.0156
1.4884 1.0224
1.4920 1.0120
1.4864 1.0168
1.5004 1.0116
1.4876 1.0132
1.4912 1.0176
1.4944 1.0192
1.4920 1.0168
1.4972 1.0152
AVG 1.4905 AVG 1.0161
STDEV 0.0052 STDEV 0.0035
CV 0.35% CV 0.34%
Density calibration with de-ionized water, correction factor 0.984
VG07-159-10
NF1 Purity
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Purity assessed by HPLCAuto-Scaled Chromatogram
1.80
2
2.48
1
4.46
1
5.68
0
6.64
47.
185
11.7
90
AU
0.000
0.005
0.010
0.015
0.020
0.025
0.030
0.035
0.040
Minutes2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00
1
2
3
4
5
6
7
Name RT Area Height Amount Units
1.802
2.481
4.461
5.680
6.644
7.185
11.790
6114
13646
4110
5419
3088
771321
2310
436
746
246
297
257
41989
116
Peak Results
Good purity noted with only minor impurities
VG07-159-11
NF1 Volatility
Onset of weight loss in TGAoccurs at a low temperature
Isothermal TGA shows material evaporates after
10 hr at 70oC
Chemical modification to NF1 will be required to eliminate volatility
114.64°C(I)99.97%(23.94mg)
95.63°C
117.07°C
Residue:-0.2287%(-0.05476mg)
-1
0
1
2
3
4
5
Der
iv. W
eigh
t (%
/°C
)
-20
0
20
40
60
80
100
120
Wei
ght (
%)
0 100 200 300 400 500
Temperature (°C) Universal V4.2E TA Instruments
71.00°C
99.74%(33.68mg)
Residue:-0.1472%(-0.04971mg)
30
40
50
60
70
80
Tem
pera
ture
(°C
)
-20
0
20
40
60
80
100
120
Wei
ght (
%)
0 200 400 600 800 1000
Time (min) Universal V4.2E TA Instruments
VG07-159-12
NF1 Differential Scanning Calorimetry
Endotherm likely due to vaporization – no exotherm noted
Heating Rate 1oC/min Heating Rate 5oC/min
Heating Rate 10oC/min Heating Rate 20oC/min
142.87°C
113.07°C322.1J/g
79.33°C
RESIDUE WT: 0.2 mg
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
Hea
t Flo
w (W
/g)
0 100 200 300 400 500Temperature (°C)
Exo Up
Universal V4.2E TA Instruments
191.23°C
153.67°C281.7J/g
110.73°C RESIDUE WT: 0.1 mg
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
Hea
t Flo
w (W
/g)
0 100 200 300 400 500Temperature (°C)Exo Up Universal V4.2E TA Instruments
177.09°C
140.01°C312.1J/g
95.92°C RESIDUE WT: 0.4 mg
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
Hea
t Flo
w (W
/g)
0 100 200 300 400 500Temperature (°C)
Exo Up Universal V4.2E TA Instruments
204.26°C
148.22°C291.0J/g
120.21°C
RESIDUE WT: 0.0 mg
-6
-4
-2
0
Hea
t Flo
w (W
/g)
0 100 200 300 400 500Temperature (°C)Exo Up Universal V4.2E TA Instruments
VG07-159-13
NF1 in a Propellant
Experimental NF1 propellant prepared for sensitivity testing
VG07-159-14
NF1 Sensitivity
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NF1 propellant– Small sample prepared– Stability evaluated– Sensitivity evaluated
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Sensitivity measurements– Category “Green”– Acceptable for scale-up
Hazard NF1 Propellant RDX
Impact, kg-cm 100 49
Friction, psi @ drop angle, o 1300 @ 90o 1200@90o
ESD, J @ 5kv 3.0 0.38
Propellant registers in the normal category for sensitivity
VG07-159-15
Conclusions
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NF1 has been successfully synthesized and characterized in a 30% overall yield
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NF1 synthesis used low cost precursors and was produced in high purity (>97%)
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NF1 Testing Results: insensitive (“green” category material) both neat and in a propellant formulation
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NF1 showed moderate volatility and it needs to be corrected by chemical modification
VG07-159-16
Acknowledgments
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We gratefully acknowledge Missile Defense Agency (MDA) Small Business Innovative Research Program for funding this research
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We are grateful to Dr. Joseph Flanagan, Flanagan Research Company, Stanwood, WA for the insightful reviews of the paper
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Author Contact Information
Dr. Ana RacoveanuPhysical Sciences Inc.20 New England Business CenterAndover, MA 01810
Ph: 978-689-0003Fax: 978-689-3232Email: racoveanu@psicorp.com