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

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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

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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

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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

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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

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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