CA1326137C - Nitrocellulose propellant composition - Google Patents
Nitrocellulose propellant compositionInfo
- Publication number
- CA1326137C CA1326137C CA000541858A CA541858A CA1326137C CA 1326137 C CA1326137 C CA 1326137C CA 000541858 A CA000541858 A CA 000541858A CA 541858 A CA541858 A CA 541858A CA 1326137 C CA1326137 C CA 1326137C
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- Prior art keywords
- propellant composition
- lead
- propellant
- ballistic
- burning
- Prior art date
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
- C06B25/00—Compositions containing a nitrated organic compound
- C06B25/18—Compositions containing a nitrated organic compound the compound being nitrocellulose present as 10% or more by weight of the total composition
- C06B25/24—Compositions containing a nitrated organic compound the compound being nitrocellulose present as 10% or more by weight of the total composition with nitroglycerine
-
- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
- C06B23/00—Compositions characterised by non-explosive or non-thermic constituents
- C06B23/007—Ballistic modifiers, burning rate catalysts, burning rate depressing agents, e.g. for gas generating
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Emergency Medicine (AREA)
- Medicinal Preparation (AREA)
- Solid Fuels And Fuel-Associated Substances (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
- Liquid Carbonaceous Fuels (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Lubricants (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Air Bags (AREA)
Abstract
ABSTRACT
Nitrocellulose Propellant Composition Nitrocellulose propellant compositions are provided comprising zinc oxide as ballistic modifier, advantageously in conjunction with one or more conventional ballistic modifiers for example, lead or copper compounds such as lead stearate, lead acetophthalate, lead B-resorcylate and basic copper salicylate. The propellant compositions exhibit good quality plateau burning over a useful pressure range for a wide range of burning rates.
Nitrocellulose Propellant Composition Nitrocellulose propellant compositions are provided comprising zinc oxide as ballistic modifier, advantageously in conjunction with one or more conventional ballistic modifiers for example, lead or copper compounds such as lead stearate, lead acetophthalate, lead B-resorcylate and basic copper salicylate. The propellant compositions exhibit good quality plateau burning over a useful pressure range for a wide range of burning rates.
Description
~326~37 NITROCELLULOSE PROPELLAN~ COMPOSITION
This invention relates to nitrocellulose (NC) based propellant composition containing ballistic modifier to produce the effect of plateau or mesa burning over significant ranges of pressure.
The preparation of nitrocellulose propellants is .~ described in Chapter 17 of the book "High Explosives and --~` Propellants" by S Fordham, 2nd ~dition Pergamon Press " 1980. The manufacture of cast double base nitrocellulose propellant is also described in United ~ingdom patent speci~ications Nos.827,012 and 1095471.
In general for a given ignition temperature the burning rate of a propellant in a combustion chamber is related i to the pressure to which it is exposed in a manner which .~ 15 can ~e expressed mathematically by the expression :~ r = kPn . ~
where r is the burning rate, p is the pressure and k and n are constants which are characteristic of the propellant. Thus r increases exponentially with increasing p and log r increases linearly with log p, the graph of log r against log p being a line of slope n. In conventional propellant without ballistic modifier, the pressure exponent n has a value of o.5 ~t~o ' ''' ' '''''' "' 0.8 and for rocket propulsion the progressive increase in burning rate with increasing pressure presents problems in designing motors to withstand the pressures which could be developed. In order to overcome this problem NC base propellant compositions containing ballistic modifiers hàve been developed, the modifier - being effective to modify the burning rate and pressure relationship so that over a useful working pressure range the pressure exponent n is reduced. In the region 10 where n=o the graph of log r against log p contains a flat portion, termed a `'plateau" and the burning is ~ermed "plateau ~urnin~'`. In some cases n is reduced to a negative value over a certain pressure range, such propellant burning being termed "mesa burning".
Ballistic modifiers causing a reduction of the pressure exponent are termed platonisation agents. Plateau burning propellants give reduced motor performance variability in the region of the plateau and mesa burning provides additional safety against the development of high pressure in the propellant container.
Ballistic modifiers (platonisation agents) commonly used include organic salts such as lead salicylate, lead stearate or lead B-resorcylate and may also include additional metal salts such as copper salicylate, copper stearate or copper benzoate. The use of such ballistic modifiers is described for example, in United States Patent Specifications 3088858, 3923564, United Kingdom Patent Specification 2121399 and Japanese Patent J55071690. For relatively fast burning propellants a favoured modifier comprises the reaction product of lead B-resorcylate and basic cupric salicylate as described in United States Patent Specifications Nos.3138499, 3994757, 39~9776 and 4001287.
The currently used ballistic modifiers are deficient in some respects. Thus platonised propellant compositions often exhibit poor reproducibility of plateaux characteristics from batch to batch, chemical - instability on long term storage, combustion instability during burning and ballistic drift on storage. There is therefore a need for improved ballistic modified propellant compositions, especially for well platonised fast burning high energy compositions containing, when - necessary, aluminium or high levels of energetic fillers such as a nitramine, for example RDX (cyclo 1,3,5-trimethylene 2,4,6-trinitramine).
15 We have now discovered that NC based propellants having improved plateau or mesa burning characteristics may be obtained by using ballistic modifier comprising zinc oxide. This modifier gives good quality plateaux which are reproducible from batch to batch and the modi~ied ? 20 propellants do not undergo ballistic drift on storage.
.
2inc oxide, by itself, is an effective ballistic modifier for NC based propellants including cast and extruded double base propellant but it is advantageously used in conjunction with other ballistic modifiers such as lead B-resorcylate and lead salicylate to enhance the platonised burning rate. With such mixed ballistic modifiers the platonised burning rate of a propellant may be "tuned" to the requirements of a particular rocket motor and the burning rata even of high burning rate propellants may be increased, in some case by 19%.
The modified propellants have improved chemical stability as reflected by improved crack test results.
This is attributable to reaction between the zinc oxide and protic acid impurities present in the propellant composition which in the absence of zinc oxide cause degradation of nitric esters.
We have also discovered that the inclusion of zinc oxide as modifier in nitrocellulose propellants improves or eliminates combustion instability which is caused by acoustic resonance waves which build up in a rocket motor cavity during burning of the propellant and cause wide fluctuations in the pressure/time burning characteristics. The improvement is believed to be attributable to the zinc oxide, because of its high ~ melting point, acting as a resonance suppressant.
`` 15 Thus in accordance with the invention an NC based ~- propellant composition comprises zinc oxide as ballistic modifier. Preferred compositions comprise a mixture of zinc oxide and one or more of the lead or copper ~`~ compounds effective as ballistic modifier. Suitable lead and copper compounds for this purpose include lead stearate, lead citrate, lead phthalate, lead acetophthalate, lead salicylate, lead B-resorcylate, basic copper salicylate, copper B-resorcylate and copper oxide.
; 25 The propellant compositions of the invention preferably contain from 2 to 8.0% by weight of ballistic modifier and, when the modifier comprises a lead or copper compound acting as ballistic modifier in conjunction ~with zinc oxide, the composition should preferably - 30 contain 0:15 to 5.0% by weight of zinc oxide.
j 1326137 In addition to the nitrocellulose and ballistic modifier the propellant compositions of the invention may contain conventional propellant ingredients including NG (in double base propellant); stabilisers, for example paranitro N-methylaniline, 2-nitrodiphenylamine or resorcinol; plasticis~rs, for example sucrose octoacetate, triacetin or dibutylphthalate; energetic constituents, for example a nitramine such as RDX or metal powder such as aluminium; burning rate moderants, for example carbon black; lubricants, for example candelilla wax; polymeric binders, for example polycaprolactone cross-linked with isocyanate; flash suppressants, for example potassium nitrate and resonance suppressants, for example silicon carbide.
Platonised propellant compositions of the invention may vary over wide ranqes of energy and burning rates. Thus useful composition may be formulated covering the energy range from about 800 calories/gm to 1200 calories/gm and burning rates from about 4mm~sec to about 45 mm/sec.
The composition may be prepared by the conventional propellant manufacturing methods as appropriate for the respective types of nitrocellulose propellant.
The invention is further illustrated by the following Examples wherein all percentages are given by weight.
The Examples were batches of propellant having the compositions shown in Table 1 prepared by standard propellant manufacturing methods as described in Chapter 17 of the book "High Explosives and Propellants", by S
Fordham, 2nd Edition Pergamon Press 1980. Apart from the zinc oxide the ingredients used were commonly used propellant constituen~s.
6 ~ 1 326 1 37 Examples 3-6 were cast double base propellants made by a standard method wherein a double base propellant powder containing most of the ingredients was prepared by a solvent incorporation method and subsequently mixed with a casting liq~id containing about half of the nitroglycerine, all ~f the triacetin and part of the stabiliser. For testing the burning rates, slabs and end burning charges were cut from the cast propellant and b-~rned in a motor at an initial temperature of 21C
(unless otherwise indicated).
Examples 1 and 2 were made by the solvent process~ The propellant of these Examples was extruded into 2 mm diameter x 18 cm long strands which were surface inhibited by treatment with vinyl lacquer to leave a constant burning end-surface. The burning rates of the strands were measured over a range of pressures when the strands were burned from the untreated end-surface in a - Crawford Bomb*strand burning apparatus under a nitrogen atmosphere at an initial temperature of 21C (unless otherwise indicated).
-This Example was a platonised solvent extruded double base propellant composition containing 4.00% of zinc oxide as the sole ballistic modifier. The ballistic properties (burning rate v pressure) are shown graphically in Fig.l as a plot of log burning rate v.
log pressure. The plot indicates that the zinc oxide gave a plateau burning rate of 18 mm/sec at a pressure range of 175-225 ~ar.
* Trade Mark ....
, This Example was a platonised solvent extruded double base propellant having the same composition as Example 1 except that the ballistic modifier consisted of 2.0% of zinc oxide and 2.0% ~f lead B-resorcylate. The ~ ballistic test results of this composition, shown graphically in Fig.2, show that this composition exhibited plateau burning at a higher burning rate of about 27 mm/sec over a pressure range of about 85-200 bar.
EXAMPLES 3(a) and 3(b) These Examples were platonised cast double base propellants having substantially the same composition _ except that Example 3(b) contained 0.34% of zinc oxide lS in addition to 1.9~ of lead B-resorcylate and 1.99% of lead salicylate as ballistic modifier. The ballistic test res~lts of these compositions are shown graphically in Fig.3. These results show that the zinc oxide produced a hiqher burning rate plateau over an increased pressure range of about 80-175 bar.
Slabs of the compositions were stored at 60C for 12 weeks and the bur~ing rates were again determined.
Example 3(a) showed 7% downward ballistic drift over the storage period whereas Example 3(b) showed essentially unchanged ballistics, thus indicating the effect of the zinc oxide in preventing the downward ballistic draft usually attributed to reaction between the lead B-resorcylate and lead salicylate in the composition.
` ~ ` 1326137 This Example was a platonised elastomer modified cast double case propellant composition containing 0.66% of zinc oxide, 1.98% of lead B-resorcylate, 1.98% of lead salicylate and 3.53% of a polymeric binder consisting of polycaprolactone crosslined with isocyanate. The burning rate tested at initial temperatures of -40, 21 and 60C were 25-26 m/sec. in each case over a platonised burning range of 100-175 bar, as shown in Fig.4.
The burning rate did not vary much with the initial tempera~ure (i.e. the temperature coefficient was low) over the range -40 to 60C in the plateau burning region.
EXANPLES 5(a) and 5(b) These Examples were platonised aluminium filled cast double base propellants having substantially the same composition except that Example 5(b) contained 0.34% of zinc oxide. 5.1 cm. cubes of both compositions were stored at 80C and tested (by X-ray) for signs of cracks or internal flaws. Example 5(a) showed cracks after 8 days whereas Example 5(b) did not show any sign of - cracking until 21 days.
9 ` 1 326 1 37 This Example was a platonised high energy elastomer modified cast double base propellant containing 0.21~
zinc oxide, 3.21% of poly~meric binder (as used in Ex.4), 19.6% RDX and 1.4~ silicon carbide. The ballistic test results shown in Fig.5 indicate that plateau burning at about 20 mm/sec. with an acceptable ~low) temperature coefficient occurs over the pressure range of 80-150 bar.
` 1 326 1 37 Ctm~06ition ~ I 1 2 3~a) 3(b) 4 5(a) 5(b) ¦ 6 Nitrocellulose (12.6gN) 40.50 40.50 40.C9 3~.89 26.47 35.57 35.40 21.15 Nitroglycerine 4~.86 46m36 47.12 47.01 56.50 43.75 43.6444.74 P-nitro-~-m~thylaniline 0.7 ~ 0.7 O.67 0.66 O.~6 0.60 O.60 O.69 2-Nitrodiphenylamine 0.3 0.3 ~.33 0.33 0.33 0.330.33 1 0.30 Iriacetin 7.44 7.44 7.59 7.59 7.69 7.44 7.44 6.C9 Zinc oxide 4.00 2.0 _ 0.34 0.66 _ 0.34 0.21 Carbon ~lack ` 0.2 0.2 0.2 0.2 0.2 1.14 1.13 0.11 Lead B-resorcylate _ 2.0 2.0 1.991.98 4.02 4.0 1.25 Lead salicylate _ _ 2.0 1.991.98 _ _ 1.2s *Polymeric ¦ Binder _ _ _ _ 3.53 _ _ 3.21 ¦ J~luminium _ _ _ _ _ 4.56 4.54 ¦ Basic cupric salicylate _ _ _ _ _ 1.94 1.93 I Resorcinol _ _ _ _ _ 0.65 0.65 I RDX _ _ _ _ _ _ _ 19.6 ¦ Silicon carbide _ _ _ _ _ _ _ 1.4 -Preparation method Solvent Solvent Cast Cast Cast Cast Cast Cast Extruded Extruded Platonised burning rate (mm./sec.) 1827 24 29 26 - ~ 20 Pressure range (bar) 175-225 85-200 80L130 80-175 100L175 - - 80-150 - Crack life - (days at .~o& ) - - - - - 8 21 *Polycaprolactone crosslinked with isocyanate.
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This invention relates to nitrocellulose (NC) based propellant composition containing ballistic modifier to produce the effect of plateau or mesa burning over significant ranges of pressure.
The preparation of nitrocellulose propellants is .~ described in Chapter 17 of the book "High Explosives and --~` Propellants" by S Fordham, 2nd ~dition Pergamon Press " 1980. The manufacture of cast double base nitrocellulose propellant is also described in United ~ingdom patent speci~ications Nos.827,012 and 1095471.
In general for a given ignition temperature the burning rate of a propellant in a combustion chamber is related i to the pressure to which it is exposed in a manner which .~ 15 can ~e expressed mathematically by the expression :~ r = kPn . ~
where r is the burning rate, p is the pressure and k and n are constants which are characteristic of the propellant. Thus r increases exponentially with increasing p and log r increases linearly with log p, the graph of log r against log p being a line of slope n. In conventional propellant without ballistic modifier, the pressure exponent n has a value of o.5 ~t~o ' ''' ' '''''' "' 0.8 and for rocket propulsion the progressive increase in burning rate with increasing pressure presents problems in designing motors to withstand the pressures which could be developed. In order to overcome this problem NC base propellant compositions containing ballistic modifiers hàve been developed, the modifier - being effective to modify the burning rate and pressure relationship so that over a useful working pressure range the pressure exponent n is reduced. In the region 10 where n=o the graph of log r against log p contains a flat portion, termed a `'plateau" and the burning is ~ermed "plateau ~urnin~'`. In some cases n is reduced to a negative value over a certain pressure range, such propellant burning being termed "mesa burning".
Ballistic modifiers causing a reduction of the pressure exponent are termed platonisation agents. Plateau burning propellants give reduced motor performance variability in the region of the plateau and mesa burning provides additional safety against the development of high pressure in the propellant container.
Ballistic modifiers (platonisation agents) commonly used include organic salts such as lead salicylate, lead stearate or lead B-resorcylate and may also include additional metal salts such as copper salicylate, copper stearate or copper benzoate. The use of such ballistic modifiers is described for example, in United States Patent Specifications 3088858, 3923564, United Kingdom Patent Specification 2121399 and Japanese Patent J55071690. For relatively fast burning propellants a favoured modifier comprises the reaction product of lead B-resorcylate and basic cupric salicylate as described in United States Patent Specifications Nos.3138499, 3994757, 39~9776 and 4001287.
The currently used ballistic modifiers are deficient in some respects. Thus platonised propellant compositions often exhibit poor reproducibility of plateaux characteristics from batch to batch, chemical - instability on long term storage, combustion instability during burning and ballistic drift on storage. There is therefore a need for improved ballistic modified propellant compositions, especially for well platonised fast burning high energy compositions containing, when - necessary, aluminium or high levels of energetic fillers such as a nitramine, for example RDX (cyclo 1,3,5-trimethylene 2,4,6-trinitramine).
15 We have now discovered that NC based propellants having improved plateau or mesa burning characteristics may be obtained by using ballistic modifier comprising zinc oxide. This modifier gives good quality plateaux which are reproducible from batch to batch and the modi~ied ? 20 propellants do not undergo ballistic drift on storage.
.
2inc oxide, by itself, is an effective ballistic modifier for NC based propellants including cast and extruded double base propellant but it is advantageously used in conjunction with other ballistic modifiers such as lead B-resorcylate and lead salicylate to enhance the platonised burning rate. With such mixed ballistic modifiers the platonised burning rate of a propellant may be "tuned" to the requirements of a particular rocket motor and the burning rata even of high burning rate propellants may be increased, in some case by 19%.
The modified propellants have improved chemical stability as reflected by improved crack test results.
This is attributable to reaction between the zinc oxide and protic acid impurities present in the propellant composition which in the absence of zinc oxide cause degradation of nitric esters.
We have also discovered that the inclusion of zinc oxide as modifier in nitrocellulose propellants improves or eliminates combustion instability which is caused by acoustic resonance waves which build up in a rocket motor cavity during burning of the propellant and cause wide fluctuations in the pressure/time burning characteristics. The improvement is believed to be attributable to the zinc oxide, because of its high ~ melting point, acting as a resonance suppressant.
`` 15 Thus in accordance with the invention an NC based ~- propellant composition comprises zinc oxide as ballistic modifier. Preferred compositions comprise a mixture of zinc oxide and one or more of the lead or copper ~`~ compounds effective as ballistic modifier. Suitable lead and copper compounds for this purpose include lead stearate, lead citrate, lead phthalate, lead acetophthalate, lead salicylate, lead B-resorcylate, basic copper salicylate, copper B-resorcylate and copper oxide.
; 25 The propellant compositions of the invention preferably contain from 2 to 8.0% by weight of ballistic modifier and, when the modifier comprises a lead or copper compound acting as ballistic modifier in conjunction ~with zinc oxide, the composition should preferably - 30 contain 0:15 to 5.0% by weight of zinc oxide.
j 1326137 In addition to the nitrocellulose and ballistic modifier the propellant compositions of the invention may contain conventional propellant ingredients including NG (in double base propellant); stabilisers, for example paranitro N-methylaniline, 2-nitrodiphenylamine or resorcinol; plasticis~rs, for example sucrose octoacetate, triacetin or dibutylphthalate; energetic constituents, for example a nitramine such as RDX or metal powder such as aluminium; burning rate moderants, for example carbon black; lubricants, for example candelilla wax; polymeric binders, for example polycaprolactone cross-linked with isocyanate; flash suppressants, for example potassium nitrate and resonance suppressants, for example silicon carbide.
Platonised propellant compositions of the invention may vary over wide ranqes of energy and burning rates. Thus useful composition may be formulated covering the energy range from about 800 calories/gm to 1200 calories/gm and burning rates from about 4mm~sec to about 45 mm/sec.
The composition may be prepared by the conventional propellant manufacturing methods as appropriate for the respective types of nitrocellulose propellant.
The invention is further illustrated by the following Examples wherein all percentages are given by weight.
The Examples were batches of propellant having the compositions shown in Table 1 prepared by standard propellant manufacturing methods as described in Chapter 17 of the book "High Explosives and Propellants", by S
Fordham, 2nd Edition Pergamon Press 1980. Apart from the zinc oxide the ingredients used were commonly used propellant constituen~s.
6 ~ 1 326 1 37 Examples 3-6 were cast double base propellants made by a standard method wherein a double base propellant powder containing most of the ingredients was prepared by a solvent incorporation method and subsequently mixed with a casting liq~id containing about half of the nitroglycerine, all ~f the triacetin and part of the stabiliser. For testing the burning rates, slabs and end burning charges were cut from the cast propellant and b-~rned in a motor at an initial temperature of 21C
(unless otherwise indicated).
Examples 1 and 2 were made by the solvent process~ The propellant of these Examples was extruded into 2 mm diameter x 18 cm long strands which were surface inhibited by treatment with vinyl lacquer to leave a constant burning end-surface. The burning rates of the strands were measured over a range of pressures when the strands were burned from the untreated end-surface in a - Crawford Bomb*strand burning apparatus under a nitrogen atmosphere at an initial temperature of 21C (unless otherwise indicated).
-This Example was a platonised solvent extruded double base propellant composition containing 4.00% of zinc oxide as the sole ballistic modifier. The ballistic properties (burning rate v pressure) are shown graphically in Fig.l as a plot of log burning rate v.
log pressure. The plot indicates that the zinc oxide gave a plateau burning rate of 18 mm/sec at a pressure range of 175-225 ~ar.
* Trade Mark ....
, This Example was a platonised solvent extruded double base propellant having the same composition as Example 1 except that the ballistic modifier consisted of 2.0% of zinc oxide and 2.0% ~f lead B-resorcylate. The ~ ballistic test results of this composition, shown graphically in Fig.2, show that this composition exhibited plateau burning at a higher burning rate of about 27 mm/sec over a pressure range of about 85-200 bar.
EXAMPLES 3(a) and 3(b) These Examples were platonised cast double base propellants having substantially the same composition _ except that Example 3(b) contained 0.34% of zinc oxide lS in addition to 1.9~ of lead B-resorcylate and 1.99% of lead salicylate as ballistic modifier. The ballistic test res~lts of these compositions are shown graphically in Fig.3. These results show that the zinc oxide produced a hiqher burning rate plateau over an increased pressure range of about 80-175 bar.
Slabs of the compositions were stored at 60C for 12 weeks and the bur~ing rates were again determined.
Example 3(a) showed 7% downward ballistic drift over the storage period whereas Example 3(b) showed essentially unchanged ballistics, thus indicating the effect of the zinc oxide in preventing the downward ballistic draft usually attributed to reaction between the lead B-resorcylate and lead salicylate in the composition.
` ~ ` 1326137 This Example was a platonised elastomer modified cast double case propellant composition containing 0.66% of zinc oxide, 1.98% of lead B-resorcylate, 1.98% of lead salicylate and 3.53% of a polymeric binder consisting of polycaprolactone crosslined with isocyanate. The burning rate tested at initial temperatures of -40, 21 and 60C were 25-26 m/sec. in each case over a platonised burning range of 100-175 bar, as shown in Fig.4.
The burning rate did not vary much with the initial tempera~ure (i.e. the temperature coefficient was low) over the range -40 to 60C in the plateau burning region.
EXANPLES 5(a) and 5(b) These Examples were platonised aluminium filled cast double base propellants having substantially the same composition except that Example 5(b) contained 0.34% of zinc oxide. 5.1 cm. cubes of both compositions were stored at 80C and tested (by X-ray) for signs of cracks or internal flaws. Example 5(a) showed cracks after 8 days whereas Example 5(b) did not show any sign of - cracking until 21 days.
9 ` 1 326 1 37 This Example was a platonised high energy elastomer modified cast double base propellant containing 0.21~
zinc oxide, 3.21% of poly~meric binder (as used in Ex.4), 19.6% RDX and 1.4~ silicon carbide. The ballistic test results shown in Fig.5 indicate that plateau burning at about 20 mm/sec. with an acceptable ~low) temperature coefficient occurs over the pressure range of 80-150 bar.
` 1 326 1 37 Ctm~06ition ~ I 1 2 3~a) 3(b) 4 5(a) 5(b) ¦ 6 Nitrocellulose (12.6gN) 40.50 40.50 40.C9 3~.89 26.47 35.57 35.40 21.15 Nitroglycerine 4~.86 46m36 47.12 47.01 56.50 43.75 43.6444.74 P-nitro-~-m~thylaniline 0.7 ~ 0.7 O.67 0.66 O.~6 0.60 O.60 O.69 2-Nitrodiphenylamine 0.3 0.3 ~.33 0.33 0.33 0.330.33 1 0.30 Iriacetin 7.44 7.44 7.59 7.59 7.69 7.44 7.44 6.C9 Zinc oxide 4.00 2.0 _ 0.34 0.66 _ 0.34 0.21 Carbon ~lack ` 0.2 0.2 0.2 0.2 0.2 1.14 1.13 0.11 Lead B-resorcylate _ 2.0 2.0 1.991.98 4.02 4.0 1.25 Lead salicylate _ _ 2.0 1.991.98 _ _ 1.2s *Polymeric ¦ Binder _ _ _ _ 3.53 _ _ 3.21 ¦ J~luminium _ _ _ _ _ 4.56 4.54 ¦ Basic cupric salicylate _ _ _ _ _ 1.94 1.93 I Resorcinol _ _ _ _ _ 0.65 0.65 I RDX _ _ _ _ _ _ _ 19.6 ¦ Silicon carbide _ _ _ _ _ _ _ 1.4 -Preparation method Solvent Solvent Cast Cast Cast Cast Cast Cast Extruded Extruded Platonised burning rate (mm./sec.) 1827 24 29 26 - ~ 20 Pressure range (bar) 175-225 85-200 80L130 80-175 100L175 - - 80-150 - Crack life - (days at .~o& ) - - - - - 8 21 *Polycaprolactone crosslinked with isocyanate.
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Claims (12)
1. A nitrocellulose based propellant composition comprising zinc oxide as a platonizing ballistic modifier so as to provide reproducable plateaux, and to suppress acoustic resonance, said propellant composition being characterized in that it has improved plateau or mesa burning characteristics, does not undergo ballistic drift on storage and has improved chemical stability.
2. A propellant composition as claimed in Claim 1, comprising, as ballistic modifier, a mixture of zinc oxide and at least one compound selected from the group consisting of lead and copper compounds which are effective as propellant ballistic modifier.
3. A propellant composition as claimed in Claim 2, wherein the said lead and copper compounds comprise at least one compound selected from the group consisting of lead stearate, lead citrate, lead phthalate, lead acetophthalate, lead salicylate, lead B-resorcylate, basic copper salicylate, copper B-resorcylate and copper oxide.
4. A propellant composition as claimed in Claim 1, containing from 2 to 8.0% by weight of ballistic modifier based on the total weight of the propellant composition.
5. A propellant composition as claimed in Claim 4, containing 0.15 to 5.0% by weight of zinc oxide based on the weight of the propellant composition.
6. A propellant composition as claimed in Claim 1, comprising a member of the group consisting of stabilizers, plasticizers, burning rate moderants, lubricants and flash suppressants.
7. A propellant composition as claimed in Claim 1, comprising a member of the group consisting of paranitro N-methylaniline, 2-nitrodiphenylamine, resorcinol, sucrose octoacetate, triacetin, dibutylphthalate, carbon black, candelilla wax, polycaprolactone cross-linked with isocyanate, potassium nitrate and silicon carbide.
8. A propellant composition as claimed in Claim 1, containing at least one energetic constituent.
9. A propellant composition as claimed in Claim 8, comprising an energetic constituent selected from the group consisting of nitramines and metal powders.
10. A propellant composition as claimed in Claim 9, comprising cyclo-1,3,5-trimethylene 2,4,6-trinitramine.
11. A propellant composition as claimed in Claim 1 having energy in the range from 800 to 1200 calories/gm.
12. A propellant composition as claimed in Claim 1, having a burning rate of 4 to 45 mm/sec.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8617239 | 1986-07-15 | ||
| GB8617239 | 1986-07-15 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1326137C true CA1326137C (en) | 1994-01-18 |
Family
ID=10601091
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000541858A Expired - Fee Related CA1326137C (en) | 1986-07-15 | 1987-07-13 | Nitrocellulose propellant composition |
Country Status (9)
| Country | Link |
|---|---|
| AU (1) | AU632281B2 (en) |
| CA (1) | CA1326137C (en) |
| DE (1) | DE3723118C2 (en) |
| FR (1) | FR2669626A1 (en) |
| GB (1) | GB2246348B (en) |
| IT (1) | IT1235642B (en) |
| NL (1) | NL194727C (en) |
| NO (1) | NO173183C (en) |
| SE (1) | SE467540B (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2727401B1 (en) * | 1994-11-29 | 1996-12-27 | Poudres & Explosifs Ste Nale | COMPOSITIONS MODIFYING BALLISTIC PROPERTIES AND PROPERGOLS CONTAINING SUCH COMPOSITIONS |
| AU3566897A (en) * | 1997-05-07 | 1998-04-02 | Russell Broad | Munitions using infrared flare weapon systems |
| RU2121470C1 (en) * | 1997-08-18 | 1998-11-10 | Федеральный центр двойных технологий "Союз" | Ballistite fuel |
| RU2167137C2 (en) * | 1999-06-29 | 2001-05-20 | Научно-исследовательский институт полимерных материалов | Ballistite fuel |
| RU2197454C2 (en) * | 2000-05-24 | 2003-01-27 | Казанский государственный технологический университет | Explosive compound |
| RU2272803C1 (en) * | 2004-10-14 | 2006-03-27 | Федеральное государственное унитарное предприятие (ФГУП) "Пермский завод им. С.М. Кирова" | Solid rocket fuel for national economy-destined articles |
| RU2281276C1 (en) * | 2004-12-10 | 2006-08-10 | Государственное образовательное учреждение высшего профессионального образования "Пермский государственный технический университет" | Solid ballistite-type propellant |
| RU2311400C1 (en) * | 2006-02-13 | 2007-11-27 | Федеральное казенное предприятие "Пермский пороховой завод" (ФКП "Пермский пороховой завод") | Solid rocket fuel for articles of national economy designations |
| RU2380346C2 (en) * | 2008-04-14 | 2010-01-27 | Федеральное государственное унитарное предприятие "Научно-исследовательский институт полимерных материалов" | Ballistite type solid rocket propellant |
| RU2636087C1 (en) * | 2016-08-09 | 2017-11-20 | Акционерное общество "Научно-исследовательский институт полимерных материалов" | Double-based solid fuel |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3138499A (en) * | 1964-06-23 | Pressure | ||
| US1905289A (en) * | 1929-08-31 | 1933-04-25 | Du Pont | Explosive |
| FR955436A (en) * | 1946-11-29 | 1950-01-14 | ||
| US3689331A (en) * | 1964-02-28 | 1972-09-05 | Us Army | Nitrocellulose base compositions and method for making same |
| US3639183A (en) * | 1965-04-16 | 1972-02-01 | Us Navy | Gas generator compositions |
| GB1277192A (en) * | 1965-12-30 | 1972-06-07 | Us Gov Sec Army | Improvements in and relating to nitrocellulose base propellant compositions |
| DE1571218A1 (en) * | 1966-07-23 | 1970-11-26 | Dynamit Nobel Ag | Surface treatment of propellant powder |
| US3506505A (en) * | 1967-12-01 | 1970-04-14 | Herzog Johanna | Nitrocellulose base propellant coated with graphite,plasticizer,and inorganic pigment |
| NO119830B (en) * | 1969-07-19 | 1970-07-06 | Raufoss Ammunisjonsfabrikker | |
| US4243444A (en) * | 1970-09-11 | 1981-01-06 | The United States Of America As Represented By The Secretary Of The Army | Ballistic modifiers, synthesis . . . propellants |
| US4659402A (en) * | 1977-12-14 | 1987-04-21 | Hercules Incorporated | Cross-linked double base propellant having improved low temperature mechanical properties |
| SE437511B (en) * | 1979-04-24 | 1985-03-04 | Bofors Ab | WANTED TO MAKE CONSOLIDATED BODY OF DOUBLE BASKET SHEETS |
| JPS609998B2 (en) * | 1982-05-07 | 1985-03-14 | 日本油脂株式会社 | propellant composition |
| GB2152920B (en) * | 1983-08-12 | 1987-06-24 | Secr Defence | Propellant composition |
-
1987
- 1987-06-11 GB GB8713679A patent/GB2246348B/en not_active Expired - Lifetime
- 1987-07-01 NO NO872742A patent/NO173183C/en not_active IP Right Cessation
- 1987-07-03 NL NL8701562A patent/NL194727C/en not_active IP Right Cessation
- 1987-07-03 FR FR8709451A patent/FR2669626A1/en active Granted
- 1987-07-06 SE SE8702783A patent/SE467540B/en not_active IP Right Cessation
- 1987-07-07 IT IT8721199A patent/IT1235642B/en active
- 1987-07-13 CA CA000541858A patent/CA1326137C/en not_active Expired - Fee Related
- 1987-07-13 DE DE3723118A patent/DE3723118C2/en not_active Expired - Lifetime
- 1987-07-15 AU AU76381/87A patent/AU632281B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE3723118A1 (en) | 1992-07-30 |
| NL194727C (en) | 2003-01-07 |
| SE8702783L (en) | 1992-03-05 |
| IT1235642B (en) | 1992-09-14 |
| GB2246348A (en) | 1992-01-29 |
| GB8713679D0 (en) | 1991-10-16 |
| NO173183B (en) | 1993-08-02 |
| NL8701562A (en) | 1992-05-06 |
| NO872742L (en) | 1991-11-28 |
| SE8702783D0 (en) | 1987-07-06 |
| GB2246348B (en) | 1993-03-03 |
| SE467540B (en) | 1992-08-03 |
| FR2669626B1 (en) | 1994-08-19 |
| FR2669626A1 (en) | 1992-05-29 |
| DE3723118C2 (en) | 2002-06-13 |
| NO173183C (en) | 1993-11-10 |
| AU632281B2 (en) | 1992-12-24 |
| NL194727B (en) | 2002-09-02 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |