US868638A - Nitro-starch explosive. - Google Patents

Description

JESSE B. BRAUN STEIN OF ALLEN TOWN PENNSYLVANIA.

NITRO-STARCH EXPLOSIVE.

Specification of Letters Patent.

Patented Oct. 22, 1907.

Application filed July 18, 1907. Serial No. 384,307-

To all whom it may concern:

Be it known that 1, Jesse B'JBRAUNsTEIN, a citizen of the United States, residing in Allentown, Pennsylvania, have invented certain Improvements in Nitr0- Starch Explosives, of which the following is a specification.

My invention relates in general to the manufacture of nitrated carbohydrates for use as explosive bases and its specific object is to produce for such purpose a stable and economical nitro-starch.

Nitro-starch is well known to be a powerfol explosive, but its commercial use heretofore has been small owing to its instability as ordinarily made and its high expense when made by methods heretofore proposed for rendering it stable. I have discovered, however, a treatment which is inexpensive and at the same time results in satisfactory stability of the resulting explosive base.

The nitro-starch may be prepared by any of the known methods but preferably by one which will give the product as much inherent stability as possible, be fore the stabilizing agent is added. I have successfully used as an acid mixture 33 to 36% nitric acid, 63 to 67% sulfuric acid and 3 to 4% water, adding 1 Weight of the starch to 4 of the acid mixture. The nitrated product is washed in any, suitable manner, water and weak solution of ammonia accomplishing the object satisfactorily.

To nitro-starch properly prepared is added a suitable quantity of powdered lime (CaO), and the nitro-starch and lime are then thoroughly mixed in any convenient manner. The preferred proportions of the ingredients referred to are 5 parts lime to 95 of nitro-starch, but from 2 to 10% of lime can be used with good results, and slightly larger proportions of lime may housed under some conditions. It is evident, however, that too large a quantity of lime will have the effect of decreasing the explosive power of the mixture.

In producing a blasting powder from the nitro-starch thus prepared and stabilized the usual agents are added to grade the powder by giving itthe desired density and securing the desired ratio of explosive force to a given weight of powder. A common moderating agent or dope for such purpose, is, for example,.

nitrate of soda (NaNO A particularly good agent for the purpose I have found in finely divided metal,

such, for example, as iron filings, preferably of a grade such as will pass through a forty mesh screen. Where the three ingredients, Intro-starch, lime and iinely divided metal are used, the proportions of nitro-starch will vary from 30 to 70% of the entire mixture, the balance being made up of lime and finely dividcd metal, the quantity of lime being, as before statcd, preferably from 2 to 10% by weight of the amount of nilro-starch and lime. It is thus possible to produce a scrics of blasting powders graded commercially as 30, 40, 50, and powders, that is to say, powders in which the explosive agent, nitro-starch, consists substantiallyof 30, 40, 50, 60 and 70% of the entire mixture. The various ingredients arc caused to be intimately intermixed in any convenient manner, and if desired, a small pcrcentagc of a suitable oil, for cxamplc, cotton seed oil, say l1}% by weight of the entire mixture, may be addcd to give consistency.

I do not in this application claim broadly a mixturc of nitro-starch with a moderating agent consisting of finely dividcd mctal, that bcing the subject of a co' pending application Serial No. 376,003, lilcd May 27, 1907.

I claim 1. An explosive base consisting of a mixture of nitro' starch and lime. 'Ihc latter being added in such proportion as to stnbilizc the nitro-sinrch in substantially the mnnncr described.

2. An explosive base consisting substantially of :1 mixture of 05 parts niliostarch and 5 parts lime. I

3. An explosive base consisting of a mixture of nitrostarch and lime, the proportion of lime in said mixture being approximately from 2 to 10%.

4. An explosive consisting of an intimate mixture of from 30 to 70% of nitro-sturch and substantially 70 to 30"! of an added material consisting of finely divided metallic iron and lime, the proportion of lime being n pproximately 5% by weight of nitro-starch and lime.

5. An explosive consisting of an intimate mixture of from 30 to 70% of nitro-slurch and substantially 70 to 30% of an added material consisting of finely divided 'metalllc iron and lime. the proportion of lime being upproximai'ely 2 to 10% by \vpight of nitro-st=1rch and lime.

In testimony whereof, I,huve signed my name to this specification, in theprescnce of two subscribing witnesses.

JESSE B. BRAUNSTEIN.

Witnesses (HAnLns II. IIowson, Jos. H. KLEIN.