LOW-SMOKE PYROTECHNIC COMPOSITION

Abstract

A low-smoke, pyrotechnic composition is provided. The composition may include Ceric Ammonium Nitrate as an oxidizer, a fuel source, stabilizer, and a binder. The use of Ceric Ammonium Nitrate as an oxidizing agent within the composition can result in reducing the amount of smoke generated during combustion of the composition, which may be beneficial for certain pyrotechnic applications. In certain constructions, the composition may include Ceric Ammonium Nitrate as an oxidizer, Nitrocellulose and Titanium as fuel sources, Cyanoguanidine as a stabilizer, Cupric Oxide as a burn rate catalyst, and any suitable binder agent. The amount of Ceric Ammonium Nitrate by percent weight of the composition may range between 20-80 percent, 30-40 percent, or 30.0-37.5 percent. In certain configurations, the amount of Ceric Ammonium Nitrate may be about 36.7 percent by weight.

Claims

1. A low-smoke, pyrotechnic composition comprising: an oxidizer comprising Ceric Ammonium Nitrate; a fuel source; a stabilizer; and a binder.

2. The low-smoke, pyrotechnic composition of claim 1, wherein said fuel source comprises at least one of Nitrocellulose, Hexamine, Cellulose Nitrate, Nitroguanidine, Red Gum, Titanium, Aluminum, Magnesium, Boron, Charcoal, Silicon, and a transition metal.

3. The low-smoke, pyrotechnic composition of claim 1, wherein said stabilizer comprises at least one of Cyanoguanidine, Dicyanodiamide, 2-cyanoguanidine, Guanidine-1-carbonitrile, Diphenylamine, Nitrodiphenylamine, Akardite, Ethyl Centralite, Methyl Centralite, and Carbonate salts.

4. The low-smoke, pyrotechnic composition of claim 1, wherein said binder comprises at least one of Ethylcellulose, Methylcellulose, Hydroxypropyl methylcellulose, Hydroxypropyl ethylcellulose polyvinyl alcohol, Viton, Parlon, polyvinyl pyrrolidone, polyethylene glycol, and polyethylene glycol-polyvinyl alcohol copolymer.

5. The low-smoke, pyrotechnic composition of claim 1 further comprising a burn rate catalyst.

6. The low-smoke, pyrotechnic composition of claim 5, wherein said burn rate catalyst comprises at least one of Cupric Oxide, Ferric Oxide, Titanium Dioxide, Bismuth Trioxide, Molybdenum Trioxide, barium peroxide, strontium peroxide, calcium peroxide, chromic oxide, silicon dioxide, manganese (II) oxide, and boron oxide.

7. The low-smoke, pyrotechnic composition of claim 1, further comprising a second oxidizer comprising at least one of nitrate salts, perchlorate salts, and metal oxides.

8. The low-smoke, pyrotechnic composition of claim 1, comprising 20 percent by weight to 80 percent by weight said Ceric Ammonium Nitrate.

9. The low-smoke, pyrotechnic composition of claim 1, comprising 30 percent by weight to 40 percent by weight said Ceric Ammonium Nitrate.

10. The low-smoke, pyrotechnic composition of claim 1, comprising approximately 36.0 percent by weight to 37.5 percent by weight said Ceric Ammonium Nitrate.

11. The low-smoke, pyrotechnic composition of claim 1, comprising 20-80 percent by weight said Ceric Ammonium Nitrate, 0-60 percent by weight said fuel source, 1-20 percent by weight said stabilizer, and 0-15 percent by weight said binder.

12. A low-smoke, pyrotechnic composition comprising: an oxidizer comprising Ceric Ammonium Nitrate; a non-metal fuel source comprising Nitrocellulose; a metal fuel source comprising Titanium; a stabilizer comprising Cyanoguanidine; a burn rate catalyst comprising Cupric Oxide; and a binder.

13. The low-smoke, pyrotechnic composition of claim 12, comprising 20-80 percent by weight said oxidizer.

14. The low-smoke, pyrotechnic composition of claim 12, comprising 30-40 percent by weight said oxidizer.

15. The low-smoke, pyrotechnic composition of claim 12, comprising approximately 36.0-37.5 percent by weight said oxidizer.

16. The low-smoke, pyrotechnic composition of claim 12, comprising 20-80 percent by weight said oxidizer, 0-60 percent by weight said non-metal fuel source, 5-20 percent by weight said metal fuel source, 1-5 percent by weight said stabilizer, 0.5-20 percent by weight said burn rate catalyst, and 0-15 percent by weight said binder.

17. The low-smoke, pyrotechnic composition of claim 12, comprising approximately 36.7 percent by weight said oxidizer, approximately 51.4 percent by weight said non-metal fuel source, approximately 3.7 percent by weight said metal fuel source, approximately 0.9 percent by weight said stabilizer, and approximately 7.3 percent by weight said burn rate catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0015] The following detailed description of the invention references specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The present invention is defined by the appended claims and the description is, therefore, not to be taken in a limiting sense and shall not limit the scope of equivalents to which such claims are entitled.

[0016] The present invention is directed to a low-smoke, pyrotechnic composition that can be used in pyrotechnic applications where it is desirable to have a minimal amount of smoke or other solid particulate matter produced as a result of combustion of the composition. The low-smoke, pyrotechnic composition of the present invention can be utilized in connection illuminating pyrotechnic compositions and/or propellant compositions depending on the desired application. For example, the low-smoke, pyrotechnic composition of the present invention may be utilized to create an illuminating light, flash or flame, heat and/or sound in connection with the combustion of the composition while limiting the overall production of smoke generated in connection with the chemical reaction and combustion.

[0017] The principal component in the low-smoke, pyrotechnic composition of the present invention is Ceric Ammonium Nitrate, which is used as an oxidizer. Ceric Ammonium Nitrate is an inorganic compound with the formula (NH.sub.4).sub.2Ce(NO.sub.3).sub.6 (chemical formula: H.sub.8N.sub.8CeO.sub.18) and is often used as an oxidant in organic synthesis. Ceric Ammonium Nitrate (CAN) can also be referred to as Diammonium cerium hexanitrate, Diammonium hexanitratocerate(2-), and Ammonium cerium nitrate (VAN). CAN is used as the main oxidizing agent in the low-smoke, pyrotechnic composition and limits the production of solid by-product, including smoke generation during combustion of the composition.

[0018] Ceric Ammonium Nitrate is necessary in the low-smoke, pyrotechnic composition of the present invention, as it generates large amounts of oxygen useful in propagating combustion, and nitrogen gas useful in propulsion; it is also readily ignitable in the presence of organic fuels. CAN has likely found limited use in the pyrotechnics industry due to availability issues as well as its ready ability to oxidize various materials at room temperature when solvated.

[0019] Decomposition of one gram of Ceric Ammonium Nitrate generates 0.53 grams of oxygen, 0.2 grams of nitrogen, and 0.1 grams of hydrogen. The mass of oxygen generated is comparable with other common oxidizers such as potassium nitrate (0.40 grams of oxygen/gram), potassium chlorate (0.39 grams of oxygen/gram), and potassium perchlorate (0.46 grams of oxygen/gram). The combustion of CAN forms 0.31 grams of Cerium (IV) Oxide and 0.13 grams of water vapor. After subtracting the oxygen that falls out as Cerium (IV) Oxide and water vapor, 0.35 grams of free oxygen are left to participate in the combustion process. Using this information, it is found that over 69% of the byproducts of the decomposition of CAN are gaseous, and the combustion of formulations using CAN as an oxidizer have noticeably reduced smoke generation.

[0020] Ceric Ammonium Nitrate is also advantageous in the low-smoke, pyrotechnic composition of the present invention due to its low melting point. Sulfur's implementation as a low-melting point fuel in black powder has a drawback in that its presence leads to large amounts of solid sulfide byproducts that increases the smoke output of the composition. CAN's low melting point and high ignitability with organic fuels greatly reduces the amount of activation energy necessary for combustion and eliminates the need for sulfur. Furthermore, Ceric Ammonium Nitrate and its byproducts are environmentally benign.

[0021] As illustrated in Table I below, according to one embodiment, the low-smoke, pyrotechnic composition of the present invention can include a fuel source, a stabilizer, a binder, and Ceric Ammonium Nitrate as an oxidizer. In certain embodiments, additional oxidizers may be utilized with the Ceric Ammonium Nitrate; however, Ceric Ammonium Nitrate is the only specific component of the composition that cannot be removed or replaced. Additional oxidizers that may be used in conjunction with the Ceric Ammonium Nitrate may include, but are not limited to, nitrate salts, perchlorate salts, and metal oxides. In certain embodiments, the low-smoke pyrotechnic composition of the present invention can include one or more of each type of component comprising the composition. In such embodiments, the low-smoke, pyrotechnic composition can include at least one fuel source agent, at least one stabilizer agent, at least one binder agent, and at least one oxidizer agent including at least Ceric Ammonium Nitrate.

[0022] The fuel can be metal or non-metal source and the composition can include multiple fuel sources in certain embodiments. Non-limiting examples of suitable fuel sources that may be used in the low-smoke, pyrotechnic composition of the present invention can include: Nitrocellulose, Hexamine, Nitroguanidine, Red Gum, Titanium, Aluminum, Magnesium, Boron, Charcoal, Silicon, any transition metals or other types of fuel source now known or hereinafter developed or commonly used in the art.

[0023] The stabilizer can be any suitable stabilizing agent, including without limitation: Cyanoguanidine, Dicyanodiamide, 2-cyanoguanidine, Guanidine-1-carbonitrile, Diphenylamine, Nitrodiphenylamine, Akardite, Ethyl Centralite, Methyl Centralite, Carbonate salts, or other type of stabilizer now known or hereinafter developed or commonly used in the art.

[0024] The binder can be a suitable compound or substance that can bind/bond the other components of the low-smoke, pyrotechnic composition. Non-limiting examples of a suitable binder that may be used in the low-smoke gas-generating composition of the present invention can include: Ethylcellulose, Methylcellulose, Hydroxypropyl methylcellulose, Hydroxypropyl ethylcellulose polyvinyl alcohol, Viton, Parlon, polyvinyl pyrrolidone, polyethylene glycol, polyethylene glycol-polyvinyl alcohol copolymer, epoxy resins and their appropriate, crosslinking compounds, or other binder agents now known or hereinafter developed or commonly used in the art.

TABLE-US-00001 TABLE I Basic Formula for Low-Smoke Pyrotechnic Composition: Formula A: Range Ceric Ammonium Nitrate (oxidizer) 20-80% Fuel Source(s) 05-60% Stabilizer(s) 01-20% Binder(s) 00-15%

[0025] As illustrated in Table II below, the low-smoke gas generating composition of the present invention can also include at least one burn rate catalyst or heat generating compound or compounds depending on the desired effect and particular pyrotechnic application. According to one embodiment, the low-smoke, pyrotechnic composition of the present invention can include Cupric Oxide as a burn rate catalyst. Other potentially suitable catalysts can include, but are not limited to, Ferric Oxide, Titanium Dioxide, Bismuth Trioxide, Molybdenum Trioxide, barium peroxide, strontium peroxide, calcium peroxide, chromic oxide, silicon dioxide, manganese (II) oxide, boron oxide or other desired compounds commonly used in the art.

TABLE-US-00002 TABLE II Basic Formula for Low-Smoke Pyrotechnic Composition: Formula B: Range Ceric Ammonium Nitrate (oxidizer) 20-80% Fuel Source(s) 05-60% Stabilizer(s) 01-20% Binder(s) 00-15% Burn Rate Catalyst(s) 0.5-20%

[0026] As illustrated in Table III below, according to one preferred embodiment of the present invention, the low-smoke, pyrotechnic composition includes Ceric Ammonium Nitrate as an oxidizer, Nitrocellulose as a non-metal fuel source, Titanium as a metal fuel source, Cyanoguanidine as a stabilizer, Cupric Oxide as a burn rate catalyst, and any suitable binder compound. The table below illustrates this preferred formula for low-smoke, pyrotechnic composition. As shown the Ceric Ammonium Nitrate can have a suitable range of 20-80 percent by weight of the overall formula. In addition, the other components of the composition can vary substantially by percent by weight and can be replaced with other suitable compounds depending on the particular application.

TABLE-US-00003 TABLE III Select Formula for Low-Smoke Pyrotechnic Composition: Formula C: Range Ceric Ammonium Nitrate (oxidizer) 20-80% Nitrocellulose (non-metal fuel source) 00-60% Titanium (metal fuel source) 05-20% Cyanoguanidine (stabilizer) 01-05% Cupric Oxide (burn rate catalyst) 0.5-20% Binder 00-15%

[0027] According to one preferred embodiment of the present invention, the low-smoke, pyrotechnic composition includes approximately 36.7% by weight of Ceric Ammonium Nitrate (50 um), approximately 51.4% by weight of Nitrocellulose, approximately 3.7% by weight Titanium (325 mesh), approximately 0.9% by weight Cyanoguanidine, approximately 7.3% by weight of Cupric Oxide, and approximately 0-15% by weight of a binder material. The specific % by weights may vary depending on the particular or desired application and or the amount of binder material utilized. For example, the particular amount by weight of Ceric Ammonium Nitrate as an oxidizer may range between 36.0-37.5% according to certain embodiments or may range between 30-40% in other embodiments. Table IV below illustrates one specific embodiment of the low-smoke, pyrotechnic composition along with potential ranges (by percent weight) of each ingredient or compound included in the composition.

TABLE-US-00004 TABLE IV Specific Formula for Low-Smoke Pyrotechnic Composition: Formula D: Specific Amount Range Ceric Ammonium Nitrate (oxidizer) 36.7% 30-40% Nitrocellulose (non-metal fuel source) 51.4% 45-55% Cyanoguanidine (stabilizer) 0.9% 0.1-3.0% Cupric Oxide (burn rate catalyst) 7.3% 5.0-10% Binder 0.0% 00-15%

[0028] The low-smoke, pyrotechnic composition of the present invention, as described, herein results in minimal solid particulate and smoke by-product production during the combustion of the composition while still providing the desired burn temperatures, burn rates and other desired effects for various pyrotechnic applications. The Ceric Ammonium Nitrate is the key ingredient in the composition of the present invention that produces comparable performance characteristics to that of black powder while reducing or eliminating its negative attributes. In particular the inclusion of Ceric Ammonium Nitrate in the low-smoke, pyrotechnic composition of the present invention in accordance with the percent by weight ranges as described herein has the effect of producing limited smoke generating during combustion of the composition when compared to traditional pyrotechnic compositions.

[0029] For safety and longevity reasons, the compositions must be stabilized through the use of hydrophobic binders such as epoxy resin, viton, or polyvinyl butyral. Any number of suitable manufacturing and production methods can be utilized in the preparation of the low-smoke pyrotechnic composition of the present invention depending on the particular embodiment, including without limitation, manufacturing and production methods currently used in the pyrotechnics industry or hereinafter developed, or any other methods or techniques used in the production of chemical compositions. The low-smoke pyrotechnic composition of the present invention has several potential benefits, including without limitation, tunable performance aspects through minimal formulation changes, and the generation of mostly gaseous byproducts which increases performance while lowering the smoke output.

[0030] From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. It will be understood that certain features and sub combinations are of utility and may be employed without reference to other features and sub combinations. This is contemplated by and is within the scope of the claims.

[0031] The constructions described above are presented by way of example only and are not intended to limit the concepts and principles of the present invention. Thus, there has been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. The terms having and including and similar terms as used in the foregoing specification are used in the sense of optional or may include and not as required. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.