AU663677B1 - Energetic Materials - Google Patents

Description

C O M M O N W E A'L T H F A I-S T R A L I A PATENT ACT 1952 COMPLETE SPECIFICATIW S (Original)

I

017 A FOR OFFICE USE Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority: n 7J1 KD Related Art: 4,, Name of Applicant: Address of Applicant: Address for Service: ROYAL ORDNANCE plc 5 Griffin House, The Strand, London WC2N England DAVIES COLLISON, Patent Attorneys, 1 Little Collins Street, Melbourne, 3000.

Complete Specification for the invention entitled: "ENERGETIC MATERIALS" The following statement is a full description of this invention, including the best method of performing it known to us -1- ROP0028 /0876J ENERGETIC MATERIALS *e g**

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500 The present invention relates to energetic materials, particularly polymer bonded explosives and gun propellants and compositions suitable therefor.

Gun propellants have for many years been produced from compositions containing blends of nitrocellulose and nitroglycerine and are therefore known as double base materials. In some cases additional energetic ingredients such as picrite are added and the propellants are known as triple compositions. For high energy applications, e.g, the propulsion of kinetic energy projectiles from an armoured tank gun, highly energetic components such as nitramines have been included in double and triple base compositions.

Double and triple base compositions, particularly for high energy applications, suffer from the disadvantage that they are highly vulnerable to unwanted ignition when subjected in a hostile environment to attack by an energetic projectile, e.g. a projectile comprising a shaped warhead charge, Recent approaches to the problem of vulnerability have involved the development of compositions which are essentially non-double base or-triplc base systems.

Although such systems can provide reduced vulnerability this is, in general terms, obtained at the expense of propellant energy.

It is an object of the present invention to provide improved insensitive energetic materials, especially 2 see 5* 5c

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4 S C er *5 C 0 plastic bonded explosives and gun propellant compositions for low vulnerability applications.

According to the present invention there is provided an energetic composition comprising the following components in the following relative proportions: Comnponent A: from ~S to 25% by weight of a polymeric binder; Component B: from I to 90% by weight of a highly energetic filler comprising at least one heteroalicyclic nitramine compound; and Component C: frcm 3% to 15.% by weight of a plasticiser which comprises at least one nitroaromatic compoundl the percentages by weight of Components A, B and C adding to 100%.

In compositions according to the present invention Component B essentially provides the high energy capability of the composition (although Component C makes and optionally Component A may make a minor contribution), Component B provides the required structural binder properties and Component C provides processibility enabling mixtures to be formed together with Components A and B and which may be worked into a suitable dough-like material which may be pressed of extruded to form suitable products, propellants. The mutual combination of these components is specially selected in compositions according to the present invention because of the unexpected advantages such a combination provides as follows.

We have found that compositions according to the present invention can be suitably processed to provide energetic materials, for use propellants which unexpectedly and beneficially can show an improved vulnerability but without a corresponding decrease in energy normally associated with such an improvement.

For example, propellant composition3 embodying the present invention generally have a high ignition temperature and possess also the beneficial properties of I I 3 I S S S

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5* S 4* 0

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relatively low flame temperatures for the level of energy involved, thereby affording the possibility of reduced barrel erosion, as well as a relatively low burning rate, the latter property beneficially allowing propellants to be made with small web sizes as described below. The compositions according to the present invention therefore can have a combination of properties which are especially suitable for the formulation of propellants for low vulherability applications.

weight, Component B comprises 70% teight and Component C com o 2% by weight, of the said Component C preferably comprises one or more compounds which telt at a temperature less than 100C and desirably is a liquid at room temperature Preferably, the or each said nitro compound of Component C is a monocyclic nitroaromatic compound; it may be a mono-nitro compound but preferably is a di- or tri-nitro compound or a mixture thereof.

Especially suitable as compounds for use in or as Component C are di- and tri-nitro benzenes or alkyl- or alkoxy-benzenes optionally r ntaining substituent groups in the aromatic ring or in the alkyl or alkoxy group(s). For example, the compcuwid may be a di- or tri-nitro derivative of an optionally substituted alkyl- or alkoxy-be'zene containing from 1 to 3 optionally substituted alkyl and/or alkoxy groups each having from 1 to 4 carbon atoms. The compound may for instance be a di- or tri-nitro derivative of an optionally substituted toluene, ethylbenzene, propylbenzene, butylbenzene, xylene, methylethylbenzene, diethylbenzene or mesitylene or one of the other families to which the compounds listed below belong.

As optional substituents for the aromatic ring in addition to nitro group(s) and alkyl or alkoxy group(s) where present in the said nitroaromatic compound(s) of -4 Component C, are pteferred groups other than halogens selected from OH, SH, N 3

NR

1 R 2 CO. OR 3or 0.0CR 4 where Rl, R 2 R 3 and R 4 are each independently H or a simple alkyl or alkoxy (containing from 1 to 4 carbon atoms) or phenyl.

Component C may for example comprise one or more of the following known compounds (where M.P./ 0 C is the melting point in degrees Celsius): compound Name II.P./OC 4 l-Jamino-2, 4-dimethyl-3-nitrobenzene 81-82 :0 5 2 -amino-1,4-dimethyl-2--nitrobenzene 676 3 l-amiv'o-3,2-dinethyl-2-nitrobenzene 4 2-amino-l,-dimety--nitrobenzene 81-8 5 0 1,-mihyo-l,-ieh--nitrobenzene 87-8 5,-mo-l,2-ieh-nitrobenzene 74-7 11 7 l-miomethoxy--nitrobenzene 8 82 1,3-dimedroxy-2-nitrobenzene 7-73 93 l,2-dimethoxy-3-nitrobenzene 76-65 1, 2-dimethoy-3,-dnitrobenzene 98 11 1,3-dimethoy 20-riitobenzene 891 17 1 ,4-dimethoy-23-dnitrobenzene 79-3 13 2 ,4-dimethoyl-4nitrobenzene 786-77 14 1, 2-dimethyl-34-dior -nitrobenzene 82 16 1, 3-dimethyl 2,-dinitrobnitoze e 9910 21 1, 4-ditrethyl-2-hydroxy-ni-nitrobenzene 87-3 22 1, 5-dimethyl-2-hydroxy-3-nitrobenzene 73 23 1,5- iimethyl-3-hydroxy-2-nitrobenzene 66-66.5 24 2, 5-dimethyl-l-hiydroxy-3-nitrobenzetie 91 5 a.

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a. a 1, 2-dine thy 1-3-nitrobenzen e 1, 2-dimethyl-4-nitrohenzene 1, 3-dimethyl-2-nitrobenzene 1, 3-dimethyl-5-nitrobenzene 1 ,4-dimethyl-2-nitrobenzene 2 ,4-dimethyl-1-riitrobenzene 1 ,3-dinitrobenzerie 1, 3-dinitro-2-ethoxybenzene 1 ,3-dinitro-5-ethoxybenzene 1, 4-din~tro-2-ethoxybenzene 2 ,4-dinitro-l-ethoxybenzene 1, 3-di-vj-tro-5-isopropyl-4-hydroxy- -6-methylbenzene 1, 2-diriitro-4-methoxybenzene 1 ,3-dinitro-5-methoxybenzrie 1, 4-dinitro-2-methoxybarlzene 2 ,4-dinitro-1-methoxybenzene 2,4-diriitro-1,3 ,5-trimethyl-benzene 1-ethoxy-2-nitrobenzene i-ethoxy-4-ni'crobenzene 1-ethyl-2-nitrobenzene 3-ethyl-3-nitrobenzeie 1-ethyl- 1-nitrobenzene 1-isobutoxy-2-ni trobenzene 4-isopropyl-l-rnethyl-2-nitrobenzete 1-isopropy-2-ritrobenzene 1-isopropyl-4-ni trobenzen e 1-mercapto--2-nitrobenzene 1-mercapto-4-nitrobenzene 1-methoxy-2-nitrobenzene 1-rethoxy-3-nitrobenzene 1-methoxy-4-ni trobenzene 2-tethoxy-1,3 ,5-trinitroberizene nitrobenzene 1-ni trc-2-triazobenzene 1-nittro-3-triazobenzene 3 0-31 13 9 59.5-60.5 97.5 9 6-98 36-87 55.5 71 205.5 97 94.5-95.5 86 2 -23 -12 (oil) 58.5 79 3 8-39 54 69 5.7 5 3-55 56 -6- 1-nitro-4-triazobenzene 61 1-nitro-2,3,5--trimethylbenizene 62 1-nitro-2,4,5-trimethylbenzene 71 63 2-nitro-1,3,5-trimethylbenzene 44 64 l,2,4-trinitrobenzene 61-62 1,3,5-trinitrobenzene 66 N-(2-nitrophenyl)-benzamide 98 67 2-nitropheny. benzoate :068 3-nitrophenyl benzoate 71-72 69 4-riitrophenyl benzoate 94-95 2,4-dinitrotoluene 71 I.71 2,5-dinitrotoluenie 53 72 2,6-dinitrotoluene 66 to 73 3,4-dinitrotoluene 58 74 2,4-diritro-6-hydroxytoluene 86 3 15-dinitro-4-hydroxytoluene 76 2-yrx-,45tiiroou 0 77 -hydroxy-3,4,5-trinitrotoluene 1021 78 2,4,6-trinitrotoluene 82 Preferably, at least 50% by weight of Component C comprises one or more alkyl substituted monocyclic dinitrobenzenes, e.g. selected from dinitrotoluenes, dinitroethylbenzenes and dinitropropyltbenzenes, Nitroaromatic compounds as described above have been found to provide energetic plasticisers which are compatible with nicramine energetic fillers and are highly suitable for use in processing mixtures of such fillers with polymeric binders. Pi~ferably, the nitroaromattc plasticiser has an igiiition temperature greater than 200 0

C.

Nitroaromatic compounds as described above are known or may be made by well known methods.

For example, in, the production of nitro derivatives of alkylbenzenes the appropriate alkylbenzene is treated with concentrated nitric and sulphuric acid at a temperature 1 -7 less than 40 0 C. Where the product obtained is a mixture of nitro compounds, e.g. containing dinitro- and trinitro derivatives, such a mixture may itself be suitable for use in or as Component C.

Although Component C desirably comprises one or more monocyclic nitroaromatic compounds, e.g. so that the monocyclic nitro compound(s) forms at least 50 per cent by weight of Component C, it may also include one or more nittoaromatic compounds containing more than one aromatic ring, e.g. one or more of the 2-ring esters listed above or one or more nitro derivatives of biphenyl, naphthalene diphenylmethane, bibenzyl or stilbene preferably containing V. two or three nitro groups in each ring. An example is a 2,2',4,4',6,6'-hexanitrostilbehe.

Although Component C is preferably constituted entirely by nitroaomatic compounds as described above it could also include other energetic and non-energetic plasticisers as optional additives. For example, Component C may additionally include a quantity of one or more known energetic plasticisers such as GAP (glycidyl azide po.ymer), BDNPA/F (bis-2,2-dinitropropylacetal/formal), 9dimethylmethylene dinitroamine, bis(2,2-dinitropropyl)formal, bis(2,2,2-trinitroethyl)formal, bis(2-fluoro-2,2-diaitroethyl)formal, diethylene glycol dinitrate, glycerol trinitrate, glycol trinitrate, triethylene glycol dinitrate, tetrethylene glycol dinitrate, trimethylolethane trinitrate, butanetriol trinitrate, or 1,2,4-butanetriol trinitrate.

Alternatively, or in addition, Component C may include one or more known non-energetic plasticisers such as dialkyl esters of adipic or phthalic acid, dibutyl phthalate, or diethyl phthalate, triacetin, tricresyl phosphate, polyalkylene glycols and their alkyl ether derivatives, e.g. polyethylene glyool, pulypropylene glycol, and diethylene glycol butylether. However, preferably at least 8 1A 0O0

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5005 desirably at least 75% by weight of Component C is constituted by one or more nitroaromatic compounds.

In the composition according to the present invention Component A may be any suitable polymer binder. It may comprise an inert binder material, an energetic binder material or a blend of inert and energetic binder materials. However, generally speaking, increasing the energetic nature of the binder increases the sensitiveness and-explosiveness of the energetic material formed the.refrom. Therefore employed binders which are energetic are desirably not highly energetic. For example where the binder comprises a blend of inert and energetic materials the inert material preferably forms at least 50% by weight of the binder.

Examples of suitable inert or non-energetic binder materials are cellulosic materials such as esters, e.g.

cellulose acetate, cellulose acetate butyrate, polyurethanes, polyesters, polybutadienes, polyethylenes, polyvinyl acetate and blends and/or copolymers thereof.

Examples of suitable energetic birder materials are nitrocellulose, polyvinyl nitrate, nitroethylene, nitroallyl acetate, nitroethyl acrylate, nitroethyl methacrylate, trinitroethyl acrylate, dinitrooropyl acrylate, C-nitropolystyrene and its derivativ-s, polyurethanes with aliphatic C- and N- nitro groups, polyesters made from dinitrocarboxylic acids and dinitrodiols.

We prefer cellulosic materials for Component A comprising 0 to 60 per cent by weight of nitrocellulose, containing 12 to 14 per cent by weight N, and 100 to per cent by weight of an inert cellulose ester, e.g., cellulose acetate, uo cellulose acetate butyrate.

Preferably, Component B comprises a solid granular or powdered material dhich can be uniformly incorporated in Component A.

9 Preferably at least 75% desirably at least 90% by weight of Component B is constituted by one or more heteroalicyclic nitramine compounds. Nitramine compounds are those containing at least one N-NO 2 group.

Heteroalicyclic nitramines bear a ring containing N-NO 2 groups. Such ring or rings may contain for example from two to ten carbon atoms and from two to ten ring nitrogen atoms. Examples of preferred heteroalicyclic nitramines are RDX (cyclo -l,3,5-trimethylene-2,4,6-trinitramine, cyclonite or Hexagen), HMX (cyclo -1,3,5,7-tetramethylene -2,4,6,8-tetranitramine, Octogen) or TATND (tetranitro-tetraminodecalin) and mixtures thereof.

Preferably, Component B comprises from 50% to 100% by weight of RDX, Desirably, for propellants, the composition includes from 70 to 80 per cent by weight of RDX.

Other high.ly energetic filler materials may be added to the nitramine(s) of Component B, the non-nitramine component(s) providing up to 25 per cent by weight of Component A. Examples of Suitable known highly energetic materials include picrite (nitroguanidine), TAGN, aromatic nitramines such as tetryl, ethylene dinitramine, and nitrate esters such as nitroglycerine (glycerol trinitrate), butane triol trinitrate or pentaerythrital tetranitrate.

Various known additives may be added to the compositions according to the present invention comprising Components A, B and C as specified above. Preferably, the additive content comprises no more than 10 per cent by weight, desirably less than 5 per cent by weight, of the combined mixture when formed into a propellant.

The additive may for example comprise one or more stabilisers, e.g. carbamite or PNMA ^para-nitromethylmethoxyaniline); and/or one or more ballistic modifiers, e.g. carbon black or lead salts; and/or one or more flash suppressants, e.g. one or more sodium or 10 potassium salts, e.g. sodium or potassium sulphate or bicarbonate.

Preferred compositions embodying the invention for use -s gun propellants comprise: nitrocellulose 8 to 10 per cent by weight cellulose acetate butyrate 6 to 12 per cent by weight RDX 70 to 80 per cent by weight nitroaromatic plasticiser 5 to 10 per cent by weight carbamite stabiliser 1 per cent by weight 6 In this composition, the nitroaromatic plasticiser is preferably selected from one of the following: *9 a mixture of dinitroethylbenzene and trinitroethylbenzene containing: dinitroethylbenzene 50-64 per cent by weight trinitroethylbenzene 36-50 per cent by weight; 2,4-dinitrotoluene; ee 4,6-dinitroo-ocresol; 2,4-dinitro-m-xylene; Compositions according to the present invention may be processed into products such as propellants by techniques which are known to those skilled in the art. The plasticiser comprising Component C is added to and absorbed by the polymer of Component A to swell and soften the polymer. If Component C includes a solid it may be melted and then added to Component A or added in a suitable solvent, e.g. acetone or ethyl acetate. Component B, preferably in a paste with an organic solvent, is blended with a mixture of Components A and C in a suitable kneader to form a homogeneous composition. Eventually, the composition produced is pressed or extruded in the form of a dough-like material through suitably shaped extrusion 11 dies. The extrusion may be carried out using a co-rotatirg twin screw extrusicn machine.

The product obtained by extrusion of compositions according to the present invention may be obtained in any suitable fo.ri. For example, where the product is a gun propellant, it may be obtained in the form of sticks or granules of known shape. Sticks are usually formed by cutting to a suitable length rods or strands extruded thLough suitable dies giving a shape including a longitudinal slot. Granules a,'e usually similarly formed by cutting to much shorter lengths rods or sticks obtainec by extrusion. Normally such granules have small holes, e.g. seven holes running lengthwise therethrough to provide s'itable burning surfaces.

An important feature of certain propellant products is the web size of the product shape or configutation. This S. parameter, well known to those skilled in the propellants art, is the minimum thickness of propellain to be burnt through from one surface to another. For xample, for a propellant product having simple tube configuration, the web thickness is the outer to inner wall thickness of the cross-sectional annulus of the tube Web size' of propellant products incorporating compositions embodying 0*.o the invention may vary over a rankle according to the specific application, e.g. from 0.5mm to 4.0mm, although the more desirable web sizes at the lower end of this range e.g. from 0,5mm to 2.0mm, will generally be suitable for most apphatironf bec uae the compositions generally have a low burning rate.

Fxamp1ss of eooipositions embodying the invention and their use in the production of propellant materials will now be described.

In the following e-xa ples the appropriate Components A, B and C (as defined above) are prepared by known methods. These components are then formed into propellant products in the following general way which is known per 12se. The solid components comprising Component A and any minor additives, e.g. stabiliser and/or flame suppressant, are loaded aS a powder into an incorporator (blender) whose blades have previously been moistened with an organic solvent. The viscous liquid comprising Component C is added to a solvent and the mixture is poured into the incorporator to which further solvent is then added. The mixture is then incorporated together for 30 minutes after which fu'"tc solvent is added and the mixture is subsequently further blended for 4 hours. Cold water is continuously run through the incorporator during blending.

After processing in the incorporator the mixture formed is dried in an oven at a temperature of typically 50-900C oo for a period of several hours and subsequently pressed or extruded into strands of the required shape and web size which or cut iAto appropriate lengths as will be readily apparent to those skilled in the art.

Products embodying the present invention comprising compositions of the following components may be made in the manner described above. In the following compositions 1 "Nitrocellulose" means nitrocellulose containing 12.6% by S* weight N.

44.

Percentage Ingredient by wgh Composition 1 Component A Cellulose acetate Component B RDX 71 Component C 2,4-dinitrotoluene 8 Carbamite 1 Compositions 2 to Component A Cellulose acetate Component B RDX 71 Component C 2,4-dinitrotoluene 4 Compound X* 4 Carbamite 1 wherein X is successively 1 to 68 and 70 to 75 as listed above 13 I n' .ec i en t Percentage by weight Composition 76 Component A Cellulose acetate butyrate Nitrocellulose Component B RDX Component Cl wherein Component Cl comprises: 2, 6-dinitrotoluene 2 ,4-dinitrotoluene 2,4,6-trinitroto,uene (where pbw parts by weight) Compc tion 77 10 pbw 4 5 pbw 45 pbw gi

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0 5 6Oe* 0O S S S

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Component A Cellulose acetate butyrate Ni tr ocel11u los e Component B RDX Comnponenit C2 wherein Cor~ponent C2 comprises: 2 ,6-dinitrotoluene 2, 4-dinitrotoluene 2,4 ,6-trinitxrotoluene pbw pbw pbw Composition 78 Component A Cellulose acetate butyrate Nitrocellulose Componefl B RDX Component C3 wherein Component C3 comprises: .,6-dinitrotoluene, 2 ,4-diritrotoluene 2,4 ,6-trinitrotoluene 2 pb w 64 pbw 3 4 pbw Composition 79 Component A Cellulose aceta'1te butyrate Nitrocellulose Component B RDX Component C4 wherein Component r.4 comprises: 2, 6-dinitro-l-ethylbenzetie 2, 4-dinit ro-l-ethylbenzeno 2,4 ,6-trinitro-l-ethylbenzene ~0pbw 4 5 pbw 4q, pbw 14 Ingredientc Percentage by weight osition Component A Cellulose acetate butyrate Nitrocellulose Component B RDX Compopnent wherein component C5 comprises: 2, 6-dinitro-l--ethylbenzene 2, 4-dinitro-l-ethylbenzene 2,4 ,6-trinitro-1~-ethylbenzene 2 pbw 54 pbw 44 pbw composition 81 Component A Cellulose acetate butyrate Nitrocellulose q 55 S S eSS S

*SSS

S

0558 5S 04 5 S Si

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S

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Sb *55 b5

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5 5 5 Component B RDX Component C6 wh~erein Component C6 comprises: 2, 6-dinitro-l--ethylbenzene 2, 4-dini'tro.-l-ethylbenzene 2 ,4,6-trinitro-l-ethylbenzene 2 pbw 64 pbw 34 pbw Composition 82 Component A Cellulose acetate butyrate Nitrocellulose Component B RDX Component C7 whereiji Component C7 comprisess I-isoptopyl-2, 6-dinitrobenzene, ]1-isopropyl-2 ,4-diriitrobenzene 1-isopropyl-3 ,4 ,6-trinitroben4-fene 10 pbw 45 pbw 45 pbw Comp~nition 83 ComPot~ent A Cellulose acetate butyrate Nitrocellulose Componient B RDX Component C8 wherein Component C8 comprises:.

1-isopropyl--2,6-dinitrobenzene 2 pbw 1-isopropylN2 ,4-.dlnitrobenzene 54 pbw 1-isopropyl-3,4,6-trinitrohenzene 44 pbw Percentage Ingredient by weight Composition 84 Component A Cellulose acetate butyrate Nitrocellulose Component B RDX 71 Component C9 9 wherein component c9 comprises: 1-isopropyl--2,6-dinitrobenzene 2 pbw l-isopropyl--2f4-dinitrobenzene 64 pbw l-isopropyl-3,4e6-trinitrobenzene 34 pbw Composition Component A Cellulose acetate butyrate 12 Nitrocellulose 8.2 Component B RDX 73.8 Component C6 Component D Carbamite I wherein Component 06 is as defined above.

Composition 86 Component A Cellulose acetate butyrate 12 *Nitrocellulose 8.2 Component B RDX 73.8 Component 010 Component D Carbarnite I wherein Component C10 comprises: 9,-i i r eh lezn 2a..

2,4-dinitro-l-ethylbenzene 28 pbw 2,4,6-trinitro-1-ethylbenzene 50 pbw i~e. Composition 87 Component A Cellulose acetate bUtyrate 8 *.Nitrocellulose Component B RDX 72 Component 010 9 Component D Carbamite 1 wherein Component C10 is as defined above.

Composition 88 Coaiponent A Cellulose acetate butyrate 6 Nitrocellulose 8 Component B RDX 77 Component CIO Component D Carbamite wherein Component CIO is as defined above.

16 Ingredient Percentage by weight Composition 89 Component A Component B Component C Component D C~mposition Component A' Component B Component C Component D Composition 91 Component A Compoent Component 8 Component D Cellulose acetate butyrate Nitrocellulose

RDX

4 ,6-diliitro-o-cresol carbamite Cellulose acetate butyrate Nitrocellulose

RDX

2, 4-dinitrotoluene Carbamite Cellulose acetate butyrate Nitrocellulose

RDX

2 ,4-dinitro-m-xylene Carbamite 12 8.2 73.8 1 12 8.2 73.8 1 12 8.2 73.8 1 .6.

*o

*N

k 4 *a Composition;' 1 to 91 show energy levels which are in the approxcimate range of 1100-1300 Joules per gram. As noted above double base compositions generally show a loweU igniition tensperature and lower vulnerability at the same respectiv.e energy levels.

Examples of the properties of some of the above compo~sitions are given in Table 1 as follows, wherein E propellant energy in KJ pet Kg, T propellant flame temperature in degrees Kelvin, d density i1b grammies per cm3 Table 1: Properties of Examples of Compositions composition *so6 666.

6 Poe

E

1178 11'~82 1216 1279 1170 1174 1168 3088 3143 3241 3453 3092 3123 32054 1.689 1,689 1.691 1 .706 1.686 1.671 1.671 66 6066 Compositions 1 to 91 show igrutioni temperatures which are 20-30 degrees Celsius or more above those of known double base and triple base compositions of the same energy level.

For example, a composition comprising; nitroglycerine nitrocellulose picrite ca b a iit e 32% by weight 32% by weight 35% by weight 1% by weight has a similar energy level to that of composition 85, but its ignition temperature* 1610C, is SignificantlY lower than the ignition temperature, 2 2 6 0 C, bf Composition

Claims (6)

1. An energetic composition comprising the following components in the following relative proportions: Component A: from 10% to 25% by weight of a polymeric binder; Component B: from 70% to 90% by weight of a highly energetic filler comprising at least one heteroalicyclic nitramine compound; and Component C: from 3% to 12% by weight of a plasticiser which comprises at least one nitroaromatic compound; the percentages by weight of Components A, B and C adding to 100%.

2. A composition as claimed in claim I and wherein Component C comprises one or more compounds which melt at a temperature less than 100 0 C.

3. A composition as claimed in claim 2 and wherein the said one or more nitro compounds is a liquid at room temperature

4. A composition as claimed in claim 1 and wherein each said nitro compound of Component C is a monocyclic nitroaromatic compound.

5. A composition as claimed in claim 4 and wherein each said nitro compound is a di- or tri-nitro compound or a mixture thereof.

6. A composition as claimed in claim 5 and wherein the compound or compounds for use in or as Component C is/are selected from di- and tri-nitro benzenes or alkyl- or alkoxy-benzenes optionally containing substituent groups in the aromatic ring or in th alkyl or alkoxy group(s'.

900316. adat.074. royal, 1.18 Y- oo -19- 00 t 0 005 0 06~4 o 4 0g9~ S 0~ S S 504 0 S 0@0 'S S .5. 0e 4 60 0S so '4* 4% A composition as claimed in claim /9 and wherein each said nitro compound is a di- or tri-nitro derivative of an optionally substituted alkyl- or alkoxy-benzene containing from 2 to 3 optionally substituted alkyl and/or alkoxy groups each having from 1 to 4 carbon atoms. A cmpsiio a caiedinclim7 A cmpoitiii s caimd i cl 4t~ and wherein each said nitro compound i~s a di- or tri-nitro derivative of an optionally substituted toluenef ethylbenzene, propylbenzene, butylbenzene, xylene, methylethylbenzene, diethylbenzene or resitylene. M. A composition as claimed in claim I and wherein at least 50% by weig7ht of Component C comprises one or more alkyl-substituted Irgon'cyclic c6initrobenzenes selected from dinitrotoluenes, d.Xnit"-roethylbenzenes and dinitropropylbenzenes. 24 A composition as claimed in claim 1 and wherein at least 50% by weight of Component C is constituted by one or more nitroaromatic compounds. M A composition as claimed in claim I and wherein component A comprises 0 to 60 per cent by weight of nitrocellulose and 100 to 40 per cent by weight of ~aa inert celluloze *,stero 13., A composit.ion a,4x claimed in claim 1 and wherein at least 75% by weigiht ol.: Component C is constituted by one or more heteroalicyclte nitratminib, compounds. I3 Eg A compositioh as ce It) claim I and wherein at least 75% by weight of Co5~y1 is constituted by one or more of the following: 7RDX (oqlco -1,3,5-trimethylene -2t4,6-trinitramine, cyolonite oZ Hegagen), HMX (cyclo -l,3,7-tetramethylene 2f4,6,8-tetranitramine, Octogen) or TATND (t-,-tranitro-tetratiinodecalin). 1,4 A composition as claimed in claim 1 and which comprises: nitrocellulose 8 to 10 per cent by weight cellulose acetate butyrate 6 to 12 per cent by weight RDX 70 to 80 per cent by weight nitroaromatic plasticiser 5 to 10 per cent by weight carbamite 1 per cent by weight. Is 14 Ul 'k nroc~position as claimed in claimj2S and wherein the nitcoaromatic plasticiser is selected from: (a:1 a mixture of dinitroethylbenzene and trinitroethylbenzene containing: clAnitroethylbenzene S0 to 64 per cent by weight trinitroethylbenzene 36 to 50 per cent by weight; all$(b) 2,4-dinitrotoluene; 4,6-.dinitro--o-cresol; 2,4-dinitro-m-xylene. M4A gun propellant product which comprises a composition as b-laimed in claim 1. Dated this 6th day of July, 1987 ROYAL ORDNANCE plc By its Patent Attorneys DAVIES COLLISON