LOVA propellant

These properties of FOX-7 and FOX-12 suggest that they are very promising candidates for IM and are likely replacement of RDX as warhead fillings. These explosives are also potential candidates for low-vulnerability ammunition (LOVA) propellants. It has been reported that FOX-12-based propellants are highly resistant to shaped charge attack. 

In order to reduce this risk, low vulnerability ammunition (popularly known by the acronym LOVA) propellants are attractive alternatives for conventional gun propellants. The incorporation of materials possessing higher ignition temperatures into propellant formulations while maintaining superior energetics, is key to the development of LOVA/insensitive propellants [17, 18]. This is usually done by a judicious combination of energetic oxidizers and suitable binders which are described in the subsequent paragraphs. 

In summary, HAN-based propellants are markedly superior to other liquid propellants and also appear to possess physical properties and a number of other characteristics necessary for their use in a practical gun. Their performance may be further enhanced by the use of some additives. These propellants are also biodegradable so that disposal is not a problem [40, 41]. The data generated as a result of extensive characterization and hazard testing indicate that HAN-based propellants are suitable for military use. The HAN-based liquid propellants also appear to offer low vulnerability characteristics comparable to the LOVA propellants [42-44]. 

Poly(NiMMO) has been used in a variety of applications, not solely in explosives but also in gun and rocket propellants [128]. British scientists have done extensive research on synthesis, characterization and application of poly(NiMMO) as a binder for gun and rocket propellants. A team led by Leach examined a range of composite LOVA propellants based on poly(NiMMO) in combination with various fillers and plasticizers. At the end of their investigation, they concluded that it is possible to formulate propellants with an impetus of up to 1300J g-1 which still show a low response to shaped charge... 

The data reported in the literature suggests that the replacement of DEP by Bu-NENA in the Dense NC/NG+ DEP/AP/AI/RDX-based composite modified double-base (CMDB) propellants results in increase in the burn rate by 18-20% at 70 kg cm pressure. The calorimetric value and percentage elongation also increase significantly. Further, thermal stability and sensitivity of such propellants are comparable with DEP-based CMDB propellants [184]. Bu-NENA is also a component of low vulnerability ammunition (LOVA) propellants [185, 186]. The introduction of butyl-NENA into SB, DB and gun propellants results in improvement of their mechanical properties and energetics and reduction in their sensitivity [187]. 

Choudhari, M.K., Pawar, S.B., and Kulkami, M.P. (1994) Evaluation of advanced LOVA propellants with various oxidizers and binders. 7th National Seminar on High Energy Materials, VSSC, Trivandrum, India, 21-22 February, 1994. 

Solid propellant compositions which have been previously discussed all sulfer from the possibility of accidental initiation from fire, impact, electric spark, etc. Therefore, attention has turned to the development of insensitive munitions with particular emphasis on low vulnerability ammunition (LOVA). LOVA propellants contain RDX or HMX, an inert polymeric binder and a plasticizer. These composite propellants are less vulnerable to initiation than nitrocellulose-based propellants. 

LOVA propellant 206 LOX = liquid oxygen 241 -+ also liquid oxygen explosives 204 LOZ = liquid ozone L-Splav = TNT with 5% trinitroxylene (russian)... 

Aron, K. and Harris, L.E., (1983), "CARS Studies of Nitramine LOVA Propellants," ARLCD-TR-83045 SBI-AD-E401101, AD-A13581314,. 

Gun Propellents. Low sensitivity gun propeUants, often referred to as LOVA (low vulnerabUity ammunition), use RDX or HMX as the principal energy components, and desensitizing binders such as ceUulose acetate butyrate or thermoplastic elastomers (TPE) including poly acetal—polyurethane block copolymers, polystyrene—polyacrjiate copolymers, and glycidyl azide polymers (GAP) to provide the required mechanical... 

B. D. Strauss and co-workers, "New Energetic Plasticizers for LOVA PropeUants," in 3rd International Gun Propellant Symposium, Dover, N.J., Oct. 1984. 

E. Schledbauer, "LOVA Gun PropeUants with GAP Binder," in Fifth International Propellant and Propulsion Symposium, ARDEC, Dover, N.J., Nov. 1991. 

Nitramine-nitrates of general structure (133) are known as NENAs and are conveniently prepared from the nitrative cleavage of A-alkylaziridines " with dinitrogen pentoxide or from the direct nitration of the corresponding aminoalcohols. These compounds find use as energetic plastisizers in explosive and propellant formulations Bu-NENA (R = n-Bu) is a component of some LOVA (low vulnerability ammunition) propellants. ... 

The reaction of aziridines and azetidine heterocycles with dinitrogen pentoxide in chlorinated solvents yields 1,2-nitramine nitrates and 1,3-nitramine nitrates respectively. In most cases yields are good to excellent, but, reactions are not as general as with the oxygen heterocycles the outcome of reactions is heavily dependent on the nature of the substituent on the exocyclic nitrogen. Some of the products from these reactions find use as melt-castable explosives i.e. Tris-X (46) and energetic plasticizers e.g. Bu-NENA (48) the latter is a component of some LOVA (low vulnerability ammunition) propellant formulations. 

Doali, J.O., Fifer, R.A., Kruezynski, D.I., and Nelson, B.J. (1989) The mobile combustion diagnostic fixture and its application to the study of propellant combustion. Part I investigation of the low pressure combustion of LOVA XM-39 propellant. Technical Report No. BRL-MR-378/5, U.S. Ballistic Research Laboratory, MD. 

Wise and Rocchio [32] have discussed the processing techniques for LOVA formulations which invariably depend on the type of binder. The polybutadiene-based formulations referred to as cured systems, are processed through a solventless process whereas formulations based on cellulose derivatives and thermoplastic elastomers as binders are processed by a solvent process similar to standard NC propellants. In conclusion, LOVA formulations offer unique propulsion systems for tanks with the potential to offer high energy and low vulnerability. 

Acetyl triethyl citrate (ATEC) Excellent plasticizer for NC and CAB-based propellants. Also imparts desirable nonvulnerability properties and was used in the original XM-39 LOVA gun propellants [167]. 

Mackowiak, H.P. (1991) Recent investigations on gun propellants and formulations for LOVA. Proc. Joint Symposium on Compatibility of Plastics and Other Materials with Explosives, Propellants, Pyrotechnics and Processing of Explosives, Propellants and Ingredients, held at San Diego,... 

In the realm of modern, nitric-ester-free - LOVA Gun Propellants, the widely used inert binders consume energy and to some extend have an undesirably high overall phlegmatizing effect on the explosive material. The high filler content of an explosive substance has a detrimental effect on the mechanical strength of this type of propellant. 

Glycidyl azide polymer was originally developed in the USA as an -> Active Binder tor - Composite Propellants. Because this gas-producing component has been shown to have a low explosion temperature, it has been used in recent years as an active binder compound in -> LOVA gun propellant. 

Since 1970, in addition to the various well-known -> Gun Powders, LOVA gun propellants have been developed and used in the production of propellants. The acronym LOVA stands for (LOw Vulnerability Ammunition) which has come to represent a type of gun propellant. 

Also propellant charges for rockets and guns have also been developed by compounding solid explosives such as nitramines (e.g. -> Cy-clonite) with plastics. Plastic explosives and plastic propellants are of interest, if low thermal and impact sensitivity is needed (- LOVA -> Armor Plate Impact Test -> Friction Sensitivity -> Heat Sensitivity - Impact Sensitivity -> Projectile Impact Sensitifity - Susan Test). 

The raw product obtained in this manner is first separated from copper chloride and then cleaned in several stages from solvent residues and low molecular weight elements. The resulting compound is a non-crystalline explosive of extremely high thermal resistance. In the field of - LOVA technology, it is used as an -< Active Binder in high ignition temperature propellants. 

For propellant charges the insensitivity is also playing an increasingly important role. Since approximately 1970 propellant charges have been developed and used under the title LOVA (low-vulnerability ammunition). Under bullet impact, shaped charge impact or fire they respond with fire in the worst case scenario, but not in deflagration and definitely not in detonation. As energetic fillers mainly RDX... 

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