US2175826A - Chemical compounds - Google Patents

Description

Patented Got. 1%, 1939 CHEMICAL COMPOUNDS Willi Brun, Bridgeport, Com, assignor to Remington Arms Company, Inc., a corporation of Delaware No Drawing. Application August 26, 1937,

, Serial No. 161,031

5 Claims.

In. patent application Serial No. '122,240 filed April 25, 1934, now Patent No. 2,116,878, May 10,

1938, by Brun and Burns there is disclosed the use, as an ingredient of ammunition priming mixtures, of a reaction product of lead nitrate and lead hypophosphite, this product probably being a double salt of lead nitrate and lead hypophosphite in molecular proportions. It is identified in said patent as lead nitrato hypophosphite, and is preferably prepared by first mixing lead nitrate and lead hypophosphite in a dry condition and subsequently moistening the mixture. This compound contains in the same crystal both an oxidizer and a fuel which tend to react with each other under such a stimulus as a comparatively light blow. The use of compounds of this character in ammunition priming mixtures is very advantageous since the usual intergranular space separating fuel and oxidizer is wholly eliminated. The present invention comprises the discovery of certain other compositions which, like lead nitrato hypophosphite, probably are or contain complex compounds having within each crystal both a fuel and an oxidizer. similar to lead nitrato hypophosphite in that they are formed by the reaction of a nitrate and a hypophosphite, and preferably in the presence of a quantity of water inadequate to efiect complete solution.

The most desirable'nitrates are those of lead and calcium. A nitrate of mercury may be used with non-alkaline hypophosphites. Withcalcium nitrate or lead nitrate there may be combined any solublehypophosphite, such as a hypophosphite of ammonia, potassium, sodium, calcium, strontium, barium, manganese, or lead. Each of the resulting compositions has certain characteristics which associate it with the nitrate from which it is derived. The group of nitrato hypophosphites derived from lead nitrate all exhibit certain properties which are characteristic of lead nitrato-lead hypophosphite, while each of those derived from calcium nitrate exhibit properties which are characteristic of calcium nitratocalcium hypophosphite. However, each individual member of each group possesses properties which quite definitely identify it as a composition of matter distinct. from all other members of either group. The reaction between the ingredients is probably incomplete especially under the method of first preparing a dry mixture of They are likewise I the reacting ingredients and subsequently moistening the dry mixture with a quantity of water inadequate to bring about complete solution.

The. group characteristics are probably due to the formation of a double salt of the metal pres- 5 ent in the nitrate; for grample, lead nitrato hypophosphite has been quite definitely identified in the reaction product of lead nitrate and calcium hypophosphite, and in the reaction product of lead nitrate and strontium hypophosphite. 10 This reaction product possesses properties of explosiveness and stability quite similar to the properties of lead nitrato hypophosphite itself. It is non-hygroscopic, retaining its crystalline and. explosive character after prolonged exposure to 5 conditions of high humidity and temperature. This fact is surprising since theoretically a reaction resulting in the formation of lead nitrato hypophosphite should leave a residue of hygroscopic calcium nitrate. In ammunition priming 20 mixtures the product performs the same function as lead nitrato hypophosphite produced in the usual manner. The calcium is apparentlycombined in some crystalline non-hygroscopic salt, which may be calcium nitrato hypophos- 25 phite. The formation of this compound is theoretically possible according to the equation:

X-ray diffraction pictures show lines which are characteristic of lead nitrato hypophosphite. They do not show lines associated with calcium nitrato hypophosphitebut this may be due to the extreniely high absorption of X-rays by lead 35 compounds, and their comparatively slight absorption by calcium compounds. The reaction product of calcium nitrate and lead hypophosphite possesses properties which difler substantially from the properties of the re- 40 action product of lead nitrate and calcium hypophosphite; both being prepared by the technic of moistening dry mixtures of the reacting materials with a quantity of water insufficient to efiect complete solution. In the reaction product of calcium nitrate and lead hypophosphite thus treated, both lead nitrate and calcium nitratocalcium hypophosphite have been identified. The product has something of the hygroscopic nature which is characteristic of calcium nitrate 60 and appears to be somewhat less desirable as an explosive than the reaction product of lead nitrate and calcium hypophosphite. The same is generally true of the reaction products of the nitrates oi lead and calcium respectively with the soluble hypophosphites heretofore mentioned. The reaction product of each of the hypophosphites with lead nitrate appears to contain lead nitrate hypophosphite, each maybe exploded by flame or impact, and each is substantially nonhygroscopic. The metal of .the hypophosphite used, like the calcium in the reaction product of lead nitrate and calcium hypophosphite, is present in an unidentified but stable form.

The above-mentioned compositions of matter, particularly the reaction product of lead nitrate and calcium hypophosphite, have been found to serve the same purposes as lead nitrato hypophosphite in ammunition priming mixtures and detonators, particularly detonators for such purposes as seismographic work.

A composition in accordance with the present invention may be prepared as follows: Dry calcium hypophosphite and dry lead nitrate of suitable granulation are thoroughly mixed in the proportions of 1.7 grams of calcium hypophosphite to 3.3 grams of lead nitrate. After thorough dry mixing, a quantity of water is added which is structure of the mixture begins to disappear.

There is a loss in volume and a cement-like paste is formed. The kneading is continued during the formation of this paste to prevent the setting of the composition into a rock-like mass and until the mixture is of uniform texture throughout.

The occurrence of a reaction and'the presence of a reaction product are established by the change in texture and the loss in volume as well as by the behavior of the product when smeared ona plate. The moisture of the smear quickly evaporates leaving a finely crystalline residue.

After drying, the composition prepared in the manner above described may be used in ammunition priming mixtures and detonators in the same manner as lead nitrato hypophosphite. Ammunition priming mixtures may also be prepared according to the method described in the above mentioned patent, that is, by preparing a dry premix of lead nitrate and calcium hypophosphite with the inert ingredients of a priming mixture, adding to the dry pre-mix an explosive ingredient and the requisite amount of water and kneading the mixture until the completion of the reaction between the lead nitrate and the calcium'hypophosphite; for example, the pre-mix may comprise to 25 parts of calcium hypophosphite, to 50 parts of lead nitrate, 6 to 12 parts of lead sulfocyanate, and 12 to 25 parts of glass. To this premix is added 20 to 40 parts of such an explosive as and calcium hypophosphite.

lead styphnate and the amount of water necessary to produce a mixture of the desired consistency. A specific example of such a mixture is as follows:

, Parts Lead styphnate 33 Calcium hypophosphite 7 Lead nitrate M Lead sulfocyanata"; 10 Glass 20 Barium nitrate 16 Mention has been made above of the double salt of calcium nitrate and calcium hypophosphite I uses for such compositions, the appended claims are to be broadly construed.

What is claimed is:

1. An explosive composition of matter which is the product of the reaction resulting from the moistening without complete solution of a dry mixture of a nitrate selected from the group consisting of the nitrates of lead and calcium, with a hypophosphite selected from the group consisting of the hypophosphites of potassium, sodium, calcium, strontium, ammonia, barium, and manganese.

2. An ammunition priming mixture containing an explosive composition of matter which is the product of the reactionlresulting from the moistening without completesolution of a dry mixture of a nitrate selected from the group consisting of the nitrates of lead and calcium, with a hypophosphite selected from the group consisting of the hypophosphites of potassium, sodium, calcium, strontium, ammonia, barium, and manganese.

3. The explosive composition of matter calcium nitrato calcium hypophosphite.

4. An explosive composition of matter which is the product of the reaction resulting from the with a; quantity of water insuflicient to efiect complete solution of a dry mixture of lead nitrate WILLI BRUN.