Preparation Method of Polyglycidyl Nitrate (PGN) Energetic Polymer and Properties of Its Based Composite Solid Propellant

Document Type : compile

Abstract

Various energetic binder materials are being investigated in an attempt to increase the energy level of explosives and propellant formulations. The nitrate ester prepolymer poly(glycidyl nitrate) (PGN) is an energetic prepolymer that is used as a binder in propellant and explosives formulations. PGN is the most energetic polymer among the energetic polymers. Three steps in PGN synthesis from glycerol are nitration, cyclization and polymerization. Glycerol is a by-product of biodiesel industry that needs purification before any chemical reaction. In this paper various preparation methods of PGN have been investigated and optimum methods are introduced. The compatibility of PGN with energetic materials in propellants or explosives is the most important property of PGN in practical applications. PGN is compatible with energetic plasticizers. Therefore, the maximum decrease in glass transition temperature (Tg) has been seen by the addition of BuNENA energetic plasticizer and maximum increase in flow behavior (lowering of viscosity) has been observed by the addition of DEGDN energetic plasticizer. The cured PGN undergoes self-decomposition or de-curing (caused by chain scission) at room temperature due to the proximity of the terminal hydroxyl groups of the polymer to the nitrate ester groups. Research works showed that the most effective way of removing the de-curing of PGN after curing is to modify the end groups of PGN with potassium carbonate. In this paper, different formulations of PGN-based propellants are studied and their combustion, ballistic and mechanical properties have been compared with typical propellants. Finally, a PGN-based propellant formulation, mixing and preparation method is introduced.

Keywords


1.
Astuti E., Supranto S., Rochmadi R., Prasetya A., Strom K., and Andersson B., Kinetic Modeling of Nitration of Glycerol, Mod. Appl. Sci., 8, 78-86, 2014.
2.
Ang H.G. and Pisharath S., Energetic Polymers, John Wiley and Sons, New York, Chap. 1-3, 2012.
3.
Manu S.K., Glycidyl Azide Polymer GAP as a High Energy Polymeric Binder for Composite Solid Propellant Applications,
Ph.D. Thesis, Mahatma Gandhi University, 2014.
4.
Agrawal J.P., High Energy Materials: Propellants, Explosives and Pyrotechnics, John Wiley and Sons, New York, Chap. 4, 2010.
5.
Hinshaw C.J., Wardle R.B., and Highsmith T.K., Propellant Formulations Based on Dinitramide Salts and Energetic Binders,
US Pat. 5,741,998, 1998.
6.
Provatas A., Energetic Polymers and Plasticisers for Explosive
Formulations- A Review of Recent Advances, Defence Science and Technology Organisation Melbourne, DSTO-TR-0966, Australia, 2000.
7.
Willer R., Stern A.G., and Day R.S., Polyglycidyl Nitrate Plasticizers,
US Pat. 5,380,777, 1995.
8.
Provatas A., Characterisation and Polymerisation Studies of Energetic Binders, Defence Science and Technology Organisation
Victoria, DSTO-TR-1171, Australia, 2001.
9.
Colclough M.E., Desai H., Millar R.W., Paul N.C., Stewart M.J., and Golding P., Energetic Polymers as Binders in Composite
Propellants and Explosives, Polym. Adv. Technol., 5, 554-560, 1994.
10.
Haji Ghasem A., Kabiri K., and Zohurian-Mehr M.J., Glycerol
as a Versatile Raw Material, Polymerization (Persian), 3, 12-26, 2013.
11.
Desai H., Cunliffe A., Lewis T., Millar R., Paul N., Stewart M., and Amass A.J., Synthesis of Narrow Molecular Weight α,ω-hydroxy Telechelic Poly(glycidyl nitrate) and Estimation of Theoretical Heat of Explosion, Polymer, 37, 3471-3476, 1996.
12.
Astuti E., Supranto R., and Prasetya A., A Thermodynamic Study of Parameters That Affect the Nitration of Glycerol with Nitric Acid, Int. J. Chem., 9, 937-940, 2015.
13.
Paraskos A.J., Dewey M.A., and Edwards W., One Pot Procedure
for Poly(glycidyl nitrate) End Modification, US Pat. 7,714,078, 2010.
14.
Sanderson A.J. and Martins L.J., Process for Making Stable Cured Poly(glycidyl nitrate), US Pat. 6,730,181, 2004.
15.
Paraskos A.J., Sanderson A.J., and Cannizzo L.F., Polymerization
of Glycidyl Nitrate via Catalysis with BF3.THF: Compatibility
with the Activated Monomer (AM) Mechanism, IM/EM Technical Symposium, 15-17 November, San Francisco, 2004.
16.
Anoop N. and Sreekumar K., Energetic Polymers, Ph.D. Thesis, Cochin University of Science and Technology, India, 2013.
17.
Shee S.K., Reddy S.T., Athar J., Sikder A.K., Talawar M., Banerjee S., and Khan M.A.S., Probing the Compatibility of Energetic Binder Poly-glycidyl Nitrate with Energetic Plasticizers:
Thermal, Rheological and DFT Studies, RSC Adv., 5, 101297-101308, 2015.
18.
Willer R.L. and McGrath D.K., Clean Space Motor/gas Generator
Solid Propellants, US Pat 5,591,936, 1997.
19.
Ghorbani M. and Bayat Y., Synthesis and Characterization of Hydroxyl-terminated Triblock Copolymer of Poly (glycidyl nitrate-block-butadiene-block-glycidyl nitrate) as Potential Energetic Binder, Polym. Sci. Ser. B Polym. Chem., 57, 654-658, 2015.
20.
Bayat Y., Razaghi Moghaddam A., Ghorbani M., Ghadiri A., Mossahebi Mohammadi M., and Dehghani H., Synthesis of Tri-Block Polycaprolactone-Poly Glycidylnitrate Polycaprolactone
as Polyol Propellant Binder, J. Energ. Mater. (Persian),
10, 25-34, 2015.
21.
Provatas A., Characterisation and Binder Studies of the Energetic
Plasticiser-glyn oligomer, Defence Science and Technology
Organisation Salisbury, DSTO-TR-1422, Australia, 2003.
22.
Zhang Z., Luo N., Wang Z., and Luo Y., Polyglycidyl Nitrate (PGN)-based Energetic Thermoplastic Polyurethane Elastomers
with Bonding Functions, J. Appl. Polym. Sci., 132, 2015, DOI: 10.1002/APP.42026