Moisture-resistant black powder substitute compositions
View Patent ↗A solid pyrotechnic composition having a flame temperature and exhibiting ballistic performance comparable to that of black powder, but which does not contain charcoal or sulfur, is provided, as is a method for making such composition. A solid pyrotechnic composition, and method for making the same, which has a flame temperature and exhibits ballistic performance comparable to that of boron/potassium nitrate and that is preferably free of boron is also provided.
1. A solid pyrotechnic composition consisting of:
oxidizer particles comprising between about 40.0 weight percent and about 90.0 weight percent of a total weight of a solid pyrotechnic composition;
organic crystalline particles comprising between about 10.0 weight percent and about 60.0 weight percent of the total weight of the solid pyrotechnic composition, wherein the organic crystalline particles comprise at least one organic crystalline compound or a mixture of the at least one organic crystalline compound and at least one salt of the at least one organic crystalline compound, wherein the at least one organic crystalline compound is selected from the group consisting of phenolphthalein and an organic crystalline compound derived from a reaction between a phenolic compound and phthalic anhydride;
ethyl cellulose comprising between about 2.0 weight percent and about 10.0 weight percent of the total weight of the solid pyrotechnic composition; and
a dry lubricant comprising between about 0.5 weight percent and about 2.0 weight percent of the total weight of the solid pyrotechnic composition.
2. The solid pyrotechnic composition of claim 1 , wherein the oxidizer particles have a mean particle size of not greater than about 30 microns.
3. The solid pyrotechnic composition of claim 1 , wherein the oxidizer particles have a mean particle size ranging from about 5 microns to about−20 microns.
4. The solid pyrotechnic composition of claim 1 , wherein the oxidizer particles comprise between about 65.0 weight percent and about 80.0 weight percent of the total weight of the solid pyrotechnic composition.
5. The solid pyrotechnic composition of claim 1 , wherein the oxidizer particles comprise at least one member selected from the group consisting of an alkali metal nitrate and ammonium nitrate and at least one member selected from the group consisting of an alkali metal perchlorate and ammonium perchlorate.
6. The solid pyrotechnic composition of claim 5 , wherein the at least one member selected from the group consisting of an alkali metal perchlorate and ammonium perchlorate comprises between about 0.5 weight percent and about 30.0 weight percent of the total weight of the solid pyrotechnic composition.
7. The solid pyrotechnic composition of claim 5 , wherein the at least one member selected from the group consisting of an alkali metal perchlorate and ammonium perchlorate comprises between about 5.0 weight percent and about 20.0 weight percent of the total weight of the solid pyrotechnic composition.
8. The solid pyrotechnic composition of claim 5 , wherein the oxidizer particles comprise potassium perchlorate.
9. The solid pyrotechnic composition of claim 5 , wherein the oxidizer particles comprise potassium nitrate.
10. The solid pyrotechnic composition of claim 9 , wherein the potassium nitrate comprises from about 5.0 weight percent to about 20.0 weight percent of the total weight of the solid pyrotechnic composition.
11. The solid pyrotechnic composition of claim 1 , wherein the organic crystalline particles comprise phenolphthalein.
12. The solid pyrotechnic composition of claim 11 , wherein phenolphalein comprises between about 13.0 weight percent and about 22.0 weight percent of the total weight of the solid pyrotechnic composition.
13. The solid pyrotechnic composition of claim 1 , wherein the organic crystalline particles and the one or more salts of the organic crystalline particles have a mean particle size not greater than about 30 microns.
14. The solid pyrotechnic composition of claim 1 , wherein the organic crystalline particles have a mean particle size not greater than about 15 microns.
15. The solid pyrotechnic composition of claim 1 , wherein a weight ratio of the at least one organic crystalline compound to the at least one salt of the at least one organic crystalline compound is at least 80:20.
16. The solid pyrotechnic composition of claim 1 , wherein the ethyl cellulose comprises about 3.0 weight percent of the total weight of the solid pyrotechnic composition.
17. The solid pyrotechnic composition of claim 1 , wherein the solid pyrotechnic composition is substantially free of sulfur and charcoal.
18. The solid pyrotechnic composition of claim 1 , wherein the solid pyrotechnic composition is substantially free of boron.
19. The solid pyrotechnic composition of claim 1 , wherein the solid pyrotechnic composition has a moisture uptake of not greater than 0.25 weight percent at 75.0 percent relative humidity at a temperature of 21.1° C. over a period of 24 hours.
20. The solid pyrotechnic composition of claim 1 , wherein the solid pyrotechnic composition is formulated to have, upon ignition, a theoretical flame temperature not greater than about 2300K.
21. The solid pyrotechnic composition of claim 1 , wherein the solid pyrotechnic composition is formulated to have, upon ignition, a theoretical flame temperature between about 1750K and 2300K.
22. The solid pyrotechnic composition of claim 1 , wherein the oxidizer particles comprise potassium nitrate.
23. The solid pyrotechnic composition of claim 1 , wherein the oxidizer particles comprise potassium perchlorate.
24. The solid pyrotechnic composition of claim 1 , wherein the dry lubricant comprises calcium stearate or graphite.