US3580753A - Tmetn-inorganic nitrate explosives blended with aluminum - Google Patents

Abstract

EXPLOSIVE MIXTURES ARE PROVIDED, BASED ON TRIMETHYLOLETHANE TRINITRATE AND AN INORGANIC NITRATE, HAVING A HIGH RATE OF DETONATION AND GOOD SENSITIVITY DUE TO THE INCORPORATION OF ALUMINUM PARTICLES IN THE EXPLOSIVE. A PROCESS ALSO IS PROVIDED FOR PREPARING SUCH EXPLOSIVE MIXTURES, BY MIXING THE INORGANIC NITRATE AND PARTICULATE ALUMINUM WITH THE TRIMETHYLOETHANE TRINITRATE.

Description

3,580,753 TMETN-IN ORGANIC NITRATE EXPLOSIVES BLENDED WITH ALUMINUM George L. Griffith, Coopersburg, Pa., assignor to Commercial Solvents Corporation, Terre Haute, Ind. No Drawing. Filed Oct. 7, 1968, Ser. No. 765,697 Int. Cl. C06b 9/00 US. Cl. 149-39 17 Claims ABSTRACT OF THE DISCLOSURE Explosive mixtures are provided, based on trimethylolethane trinitrate and an inorganic nitrate, having a high rate of detonation and good sensitivity due to the incorporation of aluminum particles in the explosive.

A process also is provided for preparing such explosive mixtures, by mixing the inorganic nitrate and particulate aluminum with the trimethylolethane trinitrate.

This invention relates to explosive mixtures comprising trimethylolethane trinitrate and ammonium nitrate or other inorganic nitrate, having a high rate of detonation and good sensitivity due to the presence of particulate aluminum, and to a process for manufacturing such explosive mixtures by blending the trimethylolethane trinitrate with inorganic nitrate and aluminum particles.

Trimethylolethane trinitrate is a liquid explosive having a high rate of detonation and a low sensitivity. It has found use in blending with other explosive sensitizers of high sensitivity, so as to make them safe to handle, with.- out, however, reducing the sensitivity of the other explosive sensitizer to initiation by a detonator, as disclosed in US. Pat. No. 3,344,005, patented Sept. 26, 1967, to Bronstein and Grifiith. However, the sensitivity of trimethylolethane trinitrate is such that it has not come into widespread use except in admixture with other explosive sensitizers.

In accordance with the invention, trimethylolethane trinitrate explosive mixtures are prepared, based on an inorganic nitrate oxidizer and trimethylolethane trinitrate as the principal if not the only explosive sensitizer. These explosive compositions have a high rate of detonation and good sensitivity because of the presence of particulate aluminum in the explosive.

It has been determined in accordance with the invention that if trimethylolethane trinitrate and the inorganic nitrate are blended with particulate aluminum, the resulting explosive mixture has a considerably higher rate of detonation and a good sensitivity.

The explosive mixtures of the invention are formulated as dry or dry-appearing particulate mixtures, as slurries, or as gels. In particulate mixtures, the trimethylolethane trinitrate although a liquid is wholly absorbed on the solid particles of inorganic nitrate and any other solid components that may be present. In slurries, enough liquid is used, in excess of that which can be absorbed by the solid ingredients (usually up to to slurry the mixture,

3,589,753 Patented May 25, 1971 and the amount of liquid therefore is from about 5% to about 30%.

Water in an amount up to about 5% reduces rate of detonation, but does not usually affect sensitivity. In amounts in excess of 5% sensitivity is also reduced. Petroleum oils have a similar effect.

Any inorganic nitrate can be employed as the oxidizer in the compositions of the invention. Ammonium nitrate is the nitrate normally used. However, other inorganic nitrates can be employed, alone or in admixture with the ammonium nitrate. Nitrates of the alkali and alkaline earth metals, such as sodium nitrate, potassium nitrate, calcium nitrate, strontium nitrate, and barium nitrate, are exemplary inorganic nitrates. Mixtures of ammonium nitrate with alkali and/or alkaline earth metal nitrates in proportions within the range from about 25 to about 95% of ammonium nitrate, and from about to about 5% of the other nitrates, are preferred in many instances, because of their high explosive power. Compositions based on ammonium nitrate as the sole inorganic nitrate are also preferred because of their high power.

Mill and prill inorganic nitrates are quite satisfactory. The inorganic nitrate can be fine, coarse, or a blend of fine and coarse materials.

The physical form of the aluminum, on the other hand, does have an effect. Any particulate aluminum can be used, such as flake, powdered, and atomized aluminum. However, aluminum having a particle size within the range from 120 to 320 mesh appears to impart the highest rate of detonation and sensitivity for a given weight of aluminum. Milled flake aluminum and flake aluminum are within this size range, and are preferred. Particles within the range from 6 mesh to virtually fine dust in size can also be used.

Since aluminum larger than mesh and smaller than 18 mesh is less effective, blends of aluminum particles of such sizes with aluminum of optimum particle size, i.e., from to 325 mesh, is a means of further controlling the eflect of the aluminum on rate of detonation.

In addition to the trimethylolethane trinitrate, the inorganic nitrate and the aluminum, which are the essential ingredients, the explosive mixtures of the invention can include one or more supplemental solid fuels, such as an additional metal fuel, or a solid carbonaceous fuel, or both. Illustrative of other particulate metals, for example, are ferrophosphorus, ferromanganese, and ferrosilicon. The metal fuel including the aluminum usually comprises from about 0.5 to about 30% of the mixture.

Useful solid carbonaceous materials are powdered coal, coal dust, charcoal, bagasse, dextrin, starch, wood meal, flour, bran, pecan meal, and similar nutshell meals. The carbonaceous fuel when present usually comprises from about 0.5 to about 30% of the mixture. Mixtures of such fuels can also be used in amounts within the range from about 0.5 to about 30%.

Sulfur can also be added. An amount of from about 0.5 to about 5% can further increase the rate of detonation.

Liquid carbonaceous fuels such as petroleum oil display a depreciating effect on rate of detonation, but may increase sensitivity, and if these are used, these effects are taken into account. By combined use of liquid carbonaceous fuel and particulate aluminum, in appropriate amounts, it is possible to control rate of detonation and sensitivity rather precisely.

Stabilizers can be included in an amount within the range from about 0.1 to about 2% of the composition. Zinc oxide, ethyl centralite, diphenylamine, carbazole, calcium carbonate, aluminum oxide and sodium carbonate are useful stabilizers.

The relative proportions of inorganic nitrate and trimethylolethane trinitrate as well as any additional explosive sensitizers will depend upon the sensitivity and explosive effect desired, and are not critical. These in turn are dependent upon the particular nitrate or nitrates use For optimum effect, the inorganic nitrate is used in amounts within the range from about 50 to about 90%, and the total explosive sensitizer including the trimethylolethane trinitrate in an amount within the range from about 10 to about 50%. The preferred ratio of nitrate to total explosive sensitizer is from about 5:1 to about 2: 1. However, from about 35 to about 75% inorganic nitrate, and from about 25 to about 65% explosive sensitizer, give quite satisfactory results in the explosive mixtures of the invention.

The effect of the aluminum on rate of detonation and sensitivity is found to be the greatest with trimethylolethane trinitrate, and is less evident with other explosive sensitizers, so far as is presently known. Consequently, the trimethylolethane trinitrate is the major, if not the only, explosive sensitizer, and preferably comprises at least 90% of the explosive sensitizer that is present. However, small amounts of other explosive sensitizers can be used, up to a maximum of 25% of the total explosive sensitizer, of which dinitrotoluene, trinitrotoluene, pentaerythritol tetranitrate, pentolite (an equal parts by weight mixture of pentaerythritol tetranitrate and trinitrotoluene), cyclonite (RDX), Composition B (a mixture of up to 60% RDX, up to 40% TNT, and 1 to 4% wax), cyclotol (Composition B without the wax), nitrostarch, nitrocellulose, tetryl, smokeless powder, and carbine ball powder are exemplary. Nitrocellulose is of particular interest in the formulation of gels, as is described below.

For some purposes, the compositions of the invention can be formulated as slurries, using an inert liquid such as water as the suspending liquid. The amount of liquid that is used is more than is absorbed by the solid ingredients, and sufiicient to produce a slurry. The slurry can have any desired consistency, from a thin, readily flowable material, to a viscous material of a semi-solid consistency. As little as 0.5% liquid may suifice. Usually, not more than 30% liquid need be used. Water may have a desensitizing effect, and this is taken into account in formulating the mixture. I

In order to prevent large amounts of unabsorbed liquid from decreasing the consistency unduly, a liquid-soluble or liquid-dispersible thickener can be added to take up the liquid. The particular material employed will depend upon the liquid that is used, water-soluble or water-dispersible thickeners being used when water is the liquid, and oilsoluble or oil-dispersible thickeners being used when the oil is the liquid. Various gums, such as guar gum and cross-linked guar gum, can be used, as well as carboxymethylcellulose, methyl cellulose, psyllium seed mucilage, polyacrylamide and pregelatinized starches, such as Hydroseal 3B, as Well as silica aerogels, finely-divided silicas, inorganic gelling agents such as alumina, attapulgite, bentonite, and like materials. Small amounts of from 0.1 to by Weight, are sufficient.

The explosive mixtures of the invention are prepared by blending at room or at an elevated temperature, mixing the inorganic nitrate and trimethylolethane trinitrate while heating them to a temperature within the range from about 100 to about 150 F. will further increase rate of 4 detonation. In this case, the trimethylolethane trinitrate and inorganic nitrate oxidizer are added to the mixer, and mixing then effected at a temperature Within the stated range. It is not necessary to heat the ingredients beyond the time required to ensure thorough mixing, using from about fifteen minutes to about one-half hour.

It is desirable to blend the trimethylolethane trinitrate and the inorganic oxidizer under these conditions without the presence of the other explosive ingredients, so as to ensure an intimate association of the trimethylolethane trinitrate and inorganic nitrate. Since, however, the trimethylolethane trinitrate and inorganic oxidizer usually by far compose the major proportion of the composition, in order to shorten the time of mixing, minor amounts of any other explosive ingredients that are to be present can also be added at the same time. These additional components comprise the aluminum, supplemental fuel, if any, the stabilizer, and any additional explosive sensitizers. Alternatively, after mixing of the trimethylolethane trinitrate and inorganic oxidizer is complete, the other explosive ingredients can be added and thoroughly blended with the mixture.

The base explosive mixture of the invention, composed of trimethylolethane trinitrate, inorganic nitrate, and petroleum oil, can be formulated to form a variety of explosives, including dry particulate mixes, such as permissible explosives, and gels, such as gelatin dynamites, ammonia dynamites, and ammonia gels. Various types of formulations are illustrated in the examples.

The compositions of the invention are particularly useful in the form of explosive gels of the trimethylolethane trinitrate in combination with nitrocellulose. The nitrocellulose and trimethylolethane trinitrate are combined with a volatile nitroparafiin solvent in a sufficient amount to dissolve the nitrocellulose and the trimethylolethane trinitrate. The solvent is then removed from the resulting composition, and as this is done, the solution thickens, and a gel of the trimethylolethane trinitrate and nitrocellulose is obtained eventually. Ihis gel composition is then formulated with additional explosive ingredients, including inorganic nitrate, and any other inorganic oxidizers, other sensitizing explosives, aluminum, and other fuels, as described above, and can be brought to any desired consistency or physical condition.

Any type of nitrocellulose can be employed in the formulation of these gels. A fully nitrated trinitrocellulose has the highest nitrogen content (14.14% nitrogen) but the commercially available trinitrocelluloses having from 13.5 to 14% nitrogen are quite satisfactory. Any nitrocellulose having from 0.5 to 3 nitro groups per anhydroglucose unit of the cellulose can be employed, with excellent results. The preferred nitrocelluloses have from about 8% to about 14.14% nitrogen.

The amount of nitrocellulose can be varied over a wide proportion, according to the sensitivity and consistency desired.

The nitroparafiin employed has no effect on the consistency of the final gel, but the relative proportions of trimethylolethane trinitrate and nitrocellulose do. Inasmuch as the trimethylolethane trinitrate is a liquid, and the nitrocellulose is a solid, the larger the proportion of trimethylolethane trinitrate, the greater the tendency of the final gel to be a thick, semi-fluid, thixotropic or soft gel. Very hard gels can be obtained employing a large proportion of nitrocellulose. In general, the proportions of trimethylolethane trinitrate and nitrocellulose required for a gel of given hardness are best determined by trial and error, because the hardness of the gel depends to a considerable extent upon the nitrogen content of the nitrocellulose.

Satisfactory hard explosive gels are obtained, of high sensitivity and adequate explosive power, when the composition contains from about 10 to about 60* parts of nitrocellulose and from about 40 to about parts of trimethylolethane trinitrate. Soft gels are obtained when the nitrocellulose proportion is from 0.2 to 10 parts, and trimethylolethane trinitrate can be varied to a considerable extent, and any proportion within the range from about 40 parts to about 99.8 parts of trimethylolethane trinitrate to from about 0.2 part to about 60 part of nitrocellulose can be used.

The higher the proportion of nitrocellulose, the higher the sensitivity and explosive power of the composition. The trimethylolethane trinitrate has a desensitizing effect. In general, the upper limit of the amount of trimethylolethane trinitrate will depend upon the explosive power and sensitivity that is desired, and the lower proportion will depend upon the degree of desensitization of the nitrocellulose that is required, for the end use of the composition.

The nitroparaflin that is employed should be sufficiently volatile at atmospheric temperatures, or at a temperature below about 60 C., under vacuum, if necessary, so that it can be removed virtually quantitatively from the composition after the trimethylolethane trinitrate and nitrocellulose have been dissolved therein, so as to form the desired gel. Such nitroparafiins have from one to about six carbon atoms and one nitro group, and include nitromethane, nitroethane, l-nitropropane, 2-nitropropane, lnitrobutane and l-nitrohexane. These nitropartffins have a boiling point below about 150 C., but higher boiling nitroparafiins can be used, if they are removed under vacuum. They are not explosive, and cannot be exploded with detonating caps, differing in this respect from the trimethylolethane trinitrate. A further distinction is their volatility, despite their high boiling point. Nitromethane, for example, the lowest molecular weight compound of this series, has a boiling point of ll.2 C., and yet it is quantitatively volatilized from the solution on standing in the atmosphere for from eight hours to three days. The relatively high boiling point is important to the formation of a gel, because it means that the nitroparafiin is only slowly volatilized from the solutions employed as a starting material in the preparation of the nitrocellulose gels. A slow volatilization of the nitroparafiin may facilitate the formation of the final explosive gel.

The amount of nitroparaflin solvent is not critical. A sufiicient amount is employed to dissolve the nitrocellulose and trimethylolethane trinitrate. Depending upon the solubility of the nitrocellulose and the trimethylolethane trinitrate, as little as 20% by weight of the composition can be employed. There is no upper limit, inasmuch as all of the nitroparaffin solvent will eventually be removed, but there is obviously no need to employ more than is necessary to dissolve the components, since any excess nitroparafiin must also be evaporated in forming the gel, with a resultant increase in the time required to form the gel, as well as in the cost of its preparation. Thus, the upper limit is normally not in excess of about 500% by weight of the nitrocellulose-trimethylolethane trinitrate.

Such gels in accordance with the invention can be employed with aluminum and inorganic nitrate oxidizer in the formation of a wide variety of explosive formulations, including gelatin dynamites, smokeless powders, permissible explosives, and nitrocarbonitrate explosives.

Gelatin and semigelatin dynamites contain, in addition to the trimethylolethane trinitrate-nitrocellulose gel, the inorganic oxidizer and aluminum and or other combustible material. The following is a general formulation:

Percent by weight Trimethylolethane trinitrate 5-95 Nitrocellulose 0.1-15 Inorganic oxidizer 5-95 Combustible material or fuel (including aluminum) O-25 ing the solution to gel by removal of the solvent. This can be expedited by warming the containers in a vacuum oven. Then, after the gels have set, the containers are capped and sealed. Stick gelatin dynamites are easily prepared in this way.

Some hard gelatin dynamites can be prepared by first mixing the nitrocellulose, nitroparaflin, and trimethylolethane trinitrate, and then allowing the nitroparaffin to evaporate, forming a viscous liquid or gel. The viscous liquid or gel is then blended with the inorganic oxidizer, aluminum and any other fuels, and any additional sensitizers desired, forming a damp granular mixture, in which the liquid or gel is coated or absorbed on the solid components. The mixture is then packaged in cartridges, using conventional dynamite pack machines.

Smokeless powders are in particulate form, and are based on the trimethylolethane trinitrate-nitrocellulose gel as one component, in combination with the usual components to control the rate of burning. The type of smokeless powders that can be formulated, using the gels and hot inorganic nitrate in accordance with the invention, include double base powders and ball grain powders. Typical general formulations are as follows:

Double base powder: Percent by weight Polyol polynitrate 5-60 Nitrocellulose 5-95 Inorganic oxidizer 050 Combustible material or fuel (including aluminum) 0-5 Ball grain powder:

Polyol polynitrate 5-60 Nitrocellulose -40 Inorganic oxidizer 0-20 Combustible material or fuel (including aluminum) 0-15 Gelled pellets of smokeless powder can be prepared by stirring the solution composed of trimethylolethane trinitrate, nitroparaffin, solvent and nitrocellulose rapidly with hot water, heating the mixture at an elevated temperature in order to remove the nitroparafiin and set the gel particles, while at the same time dispersing the solution into small droplets, so that the gel particles are formed in finely-divided dispersed form in the water. The particles can then be separated from the water by screening and drying. The resulting composition is a pelleted smokeless powder, the size of whose pellets depends upon the degree of dispersion and the mesh size of the screen through which the composition is passed.

The explosive mixtures of the invention are sufficiently sensitive so that frequently they can be detonated with an ordinary initiator or blasting cap. However, when not, the compositions can be fired with the aid of a small booster charge. Combinations of the explosive mixtures as powders together with an initiator and/ or booster in the same container can be prepared and marketed as a combined blasting agent. The explosive compositions and the booster or initiator can be separately packaged as a composite in a single container, and can also be marketed in this form. Any conventional initiator or booster charge available in the art can be employed. Pentaerythritol tetranitrate, pentolite, tetryl and cyclonite, preferably in cast form, are exemplary booster charges.

The following examples in the opinion of the inventor represents the best embodiments of the invention.

The power of the explosives of the examples was determined using the standard tests for determining sensitivity, density, rate of detonation, and stick weight.

ethane trinitrate, flake aluminum, and other ingredients were all mixed together at F. for twenty minutes.

These compositions had the following formulation:

stick weights. Blending with flake aluminum (Examples TABLE I 4 and 5) lowers density and improves rate of detonation.

Parts by weight EXAMPLES 7 TO 10 Con- 5 A group of four formulations was prepared at 120 Example 1 2 3 R, having amounts of trimethylolethane trinitrate rang- Comjpositigfiitl 1th t t t 15 15 O0 15 0O 15 00 ing from 15 to 20% by weight, and different forms of rime y 0 e 8118 I'lIll I3. 0- Ammoniumnitratcgraincd s0. 00 80.00 s0. 00 80.00 alummum' These formulatlons were as follUWs- Aluminum-flake (320 mesh) 2. 00 2. 00 2. 00 Nut meal 5. 00 5. 00 00 Water--- 1. 00 i. 00 1.00

Total 100.00 103.00 103.00 105. 00 TABLE III Test results: Parts by weight Sand density (g./cc.) 0.955 0.885 0.902 0.94 Stick weight (g.) (1% inches x 8 ExampleNumher: 7 8 9 10 inches) 134 125 139 132 Sensitivity (1iY10hX4in0h6S) 0) Q) Composition:

Rate of detonation (1% inches x 8 Trimethylolethane triniti'ate 20.00 20.00 20.00 20.00

inches) (meters/second) 556 2,749 ,78 2,364 Ammoniumnitrategrained 63.00 63.00 63.00 63.00

Sodium nitratcmill 10.00 10.00 10.00 10.00

1N 0. %cap. Flake aluminum (-320mesli) 2. 00 2.00 2. 00 2. 00 Wheatilour 5.00 5.00 5.00 5.00

It IS evident from a comparison of Examples 2 and OilNo.5 1.00 0. 30 2. 00

3 withthe control that the addition of aluminum consid Sand density (LL/my L19 mg 1.19 1'19 erably increased the rate of detonation. All these composi- Stick might (g). (1% inches x s inches) 100 100 100 160 Hons had good sensltmty' Sensitivity (linclix iinchcs) EXAMPLES 4 TO 6 Rate of detonation (1% inches x 8 4 112 inches) (meters/second) }2,s0a 3,867 1, 054 Three formulations were prepared at 120 F., having amounts of trimethylolethane trinitrate ranging from 10% 1 N pto 20%, and using powdered and flake aluminum. These formulations had the following composition:

TABLE H The trimethylolethane trinitrate, sodium nitrate and Parts by weight ammonium nitrate were blended with the other ingredients Example Number 4 5 6 simultaneously, and the mixing time at 120 F. was onehalf hour.

Composition:

Trimethylolethano trinitrate 10. 00 15. 00 20. 00 All four, fnpos1t1ons had good i of detoilatloni and Ammonium nitrategrained 73.00 1 .9 90 good sensitivity. The effect of the oil in reducing rate of Sodiumniti'ate 1.00 0.0

Almeg 90-30a1uminum powder (30inesh) 1 00 00 200 detonation is evident from a comparison of Examples Flake aluminum 1. 00 1. 00 8, 9 and 10 with Example 7. Thus, by a blend of particulate aluminum and oil, in appropriate amounts, it is possi- Watci' i. ble to closely control rate of detonation, without affecting Total 00- 00 iti it Test results: 1

Sand density (g./cc.) 0.035 0. 075 1. 23 XAMPLES 11 TO 15 Stickweight(g.)(1%inchcsx8inchcs) 127 132 165 Sensitivity (linchx iinches) 0 A group of five formulations was prepared using alumi- Rate of detonation (1% inches x 8 inc es (meterslsecond) 2,200 2 425 2 482 num 111 various foims of particle, ranging from flake to atomized aluminum. These formulations had the follow- No. /cai ing composition, including Example 7 for comparison:

TABLE IV Parts by Weight Example Number 7 11 12 13 14 15 Composition:

Trimcthyloletliane triniti'ate 20. 00 20.00 20.00 20. 00 20.00 20. 00 Ammonium nitrate e3. 00 63. 00 c3. 00 63.00 63.00 03.00 Sodium niti-atc 10. 00 10. 00 10.00 10. 00 10. 00 Wheat flour 5. 00 5. 00 5.00 5. 00 5. 00 Flake aluminum (320 mcsh) 2. 00 Almeg -18 aluminum powder (-180-90 mesh) 00 M-30 aluminum powder (30 mesh) 2. 00 Atomizetl 12120 aluminum mesh) 2. 00 100 P aluminum powder (230 mesh) 00 Alcoa 606 aluminum fine flake (320 mesh) 200 Test results:

Sand density (g./cc.) 1.19 1.11 1.11 1.11 1.11 1.19 Stick weight (g.) (1% inches X 8 inches) 100 150 150 150 Sensitivity (1 inch x 4 inches) (I) Rate of detonation (1% inches x 8 4 112 inches (meters/second) 3'908 3,503 3,195 3,111 3, 427 3,750

1 No. cap.

These compositions had good rates of detonation and good sensitivity.

It is evident from Example 6 that aluminum powder is less effective than flake aluminum, since it gives a com- These formulations were mixed at 130 F. for one-ha1f hour. The trimethylolethane trinitrate and ammonium nitrate and sodium nitrate were blended with the aluminum and the wheat flour, and the entire mixture was position having a lower rate of detonation relative to the 75 heated at 130 F. for the full mixing time.

All six compositions had good sensitivity, and good fifteen minutes, and the water and guar gum then blended rates of detonation. in. The formulations were as follows:

TABLE VI Parts by Weight;

Example Number 18 19 20 21 22 23 24 Composition:

Trimethylolethane trinitrate 15. O 15. 00 15. 00 15.00 15. 00 15. O0 15. 00 Ammonium nitrate-grained- 83. 00 80. 90 78. 80 76. 70 74. 60 72. 50 70. 40 Flake aluminum (325 mesh) 2. 00 2. 00 2. 00 2. 00 2. 00 2. 00 2. 00 Water 0. ()0 2. 00 4. 00 6. 00 8. 00 10. 00 12. 00 Guar gum (537Z8) 0. 0.20 0.30 0. 40 0.50 0. 60

Total 100.00 100.00 100. 00 100.00 100. 00 100.00 100.00

Test results:

Sand density (cc/cc.) 1.03 1.18 1. 32 1. 46 1. 46 1. 46 1. 46 Sensitivity (1 inch x 4 inches) Rate of detonation (1% inches x 8 inches) (meters/ second) 3, 031 2, 832 2, 489 2, 489 2, 388 Stick weight (g). (1% inches x 8 inches) 140 160 177 195 195 195 195 N0. cap. 2 No. 2 cap. 3 No. 5 cap. 4 No. 16 cap. 6 No ROD.

It is evident that the form of the aluminum has a con- These were all thick slurries, and had good rates of siderable eifect upon the detonation. The highest rate of 20 detonation and good sensitivity, compared to the dry EXAMPLES 16 AND 17 Two compositions were prepared, mixing the ingreformulation. The effect of Water in reducing rate of detonation and sensitivity is apparent.

EXAMPLES 25 TO 27 A group of six permissible explosive formulations was prepared, at room temperature, having the composition shown in Table VII. Three were controls without aluminum.

TABLE VII Parts by weight Con- Con- 0011- Example Number trol A 25 trol B 26 trol C 27 Trimethylolethane trinitrate... 7. 50 7. 50 15. 00 15. 00 20. 00 20. 00 Ammonium nitr e-gr ne 61. 60. 10 56. 45 55. 10 58. 70 52. 60 Sodium nitrate 10. 00 10. 00 10. 00 10. 00 10. 00 10. 00 Sodium chlolid 10. 00 10. 00 10. 00 10. 00 10. 00 10. 00 Zinc oxide 0.30 0.30 0.30 0.30 O. 30 0. 30 Oil No. 5 O. 75 0. 1O 0. 75 0. 10 1. 00 0. 10 10. 00 10. 00 5. O0 5. 00 0. O0 0. 00 0. 00 2. 00 0. 00 2. 00 0. 00 2. 00 0. 00 0. 00 2. 2. 50 5. 00 5. 00

Test results:

Sand density (g./cc.) 0. 665 0. 680 0. 880 0. 880 1. 310 1. 310 Sensitivity (1 inch x 4 inches) Rate of detonation (1% inches x 8 inches) (meters/second) 1, 630 1, 930 2, 364 2, 482 2, 072 2, 888 Stick weight (g.) (13 inches x 8 inches). 86 94 120 120 175 1 No. 1 cap. 2 No. cap.

clients at room temperature, and having the formulation set out in Table V:

TABLE v Parts by weight Example Number 16 17 Composition:

Trimethylolethane trinitrate- Ammonium nitrat Almeg 90-30 aluminum granules (30 mesh Flake aluminum 325 mesh) 1 No. cap.

These formulations had good rates of detonation, and high sensitivity. The superiority of flake aluminum to granular aluminum is evident.

EXAMPLES 18 TO 24 A group of seven thickened slurried formulations was prepared, and compared with a dry formulation of like composition. These formulations were mixed at room temperature, the explosive ingredients being mixed for These formulations had excellent rates of detonation, compared to the controls, and sensitivity also was high.

EXAMPLES 28 TO 31 A group of four ammonia dynamites was prepared, mixing the ingredients together at room temperature and having the following formulations:

TABLE VIII Parts by weight Example Number 28 29 30 31 Trimethylolethane trinitrate 14.00 14.00 14.00 14. 00 Ammonium nitrate-grained 42. 10 51. 60 61. 10 65. 60 Sodium trate 35.00 25. 00 15. 00 10. 00 Zinc oxide--- 0. 30 0. 30 0. 30 0. 30 Oil No 5-- 0. 10 0. 1O 0. 10 0. 10 Bagasse 5. 00 5. 00 5. 00 5. 00 Wheat flour 2. 00 2. 00 2. 00 2. 00 Flake aluminum (-325 mesh) 1. 50 2.00 2. 50 3.00

Total 100. 00 100.00 100. 00 100. 00

Test results:

Sand density (g./cc.) 0. 88 0. 86 0. 82 0. 82 Stick weight (g.) (1%; inches x 8 inches 117 112 112 Sensitivity (1 inch x 4 inches) Rate of detonation (1% inches x 8 inches) (meters/second) 2,124 2,161 2, 303 2,405 Ballistic pendulum value (No. 6

cap) 9.1 10.2 11. 2 11. 9

1 N 0. cap.

1 1 These formulations had good rates of detonation, good sensitivity, and good ballistic pendulum values.

EXAMPLES 32 TO 34 A group of six water-resistant permissible explosives These formulations had good rates of detonation, good sensitivity, and good ballistic pendulum value.

EXAMPLES 39 TO 42 was prepared, mixing the ingredients at room tempera- Four ammonia dynamites having low rates of detonature. These had the following formulation: tion were prepared, mixing the ingredients at room tem- TABLE IX Parts by weight Con- Con- Con- Example Number trol A 32 trol B 33 trol O 34 Composition:

Trimethylolethane trinitrate 7. 50 7. 50 15.00 15.00 20. 00 20.00 Ammonium nitrate-gfaine 59. 45 58. 54. 45 53. 10 51. 70 50. 60 10. 00 10. 00 10. 00 10. 00 10. 00 10. 00 10.00 10.00 10. 00 10.00 10. 00 10. 00 0. 0. 30 0. 30 0. 30 0. 30 0. 30 0. 75 0. 10 0. 75 0. 10 1. 00 0. 10 Bagasse 10. 00 10. 00 5. 00 5. 00 0. 00 0. 00 Flake aluminum 0. 00 2. 00 0. 00 2. 00 0. 00 2. 00 Jaguar 100 guar gum 2. 00 2. 00 2. 0O 2. 0O 2. 00 2. 00 Wheat flour 0. 00 0. 00 2. 50 2. 50 5.00 5. 00

Total 100. 00 100.00 100.00 100. 00 100. 00 100. 00

Test results:

Sand density (g./cc.) 0. 65 0. 64 0.88 0. 88 1. 29 1. 29 Stick Weight (g.) (1% inches 11811101105). 88 88 120 120 172 172 Ballistic pendulum value (No. 6 cap). 9. 3 9. 6 9. 5 9. 7 0. 6 9. 9 Sensitivity (1 inch x 4 inches) Rate of detonation (1% inches x 8 inches) (meters/second) 1. 443 1,572 2,210 2,358 2,133 2,838

N0. 2 cap. 2 No. i cap. 3 N0. 5 cap.

These had good rates of detonation, compared to the perature for fifteen minutes. These had the following controls, and good sensitivity and ballistic pendulum formulations: value.

EXAMPLES 35 TO 38 TABLE XI Four water-resistant ammonia dynamites were prepared, Parts by having the following formulation, The ingredients were Example Number; 30 40 41 42 mixed together at room temperature for fifteen mlnutes. Composition: I

Trimethylolethane trinltrate 14. 00 14. 00 14. 00 14. 00 Ammonium nitrategrained 41. 20 50. 70 60.20 64. 70 Sodium nitrate 35.00 25. 00 15.00 10. 00 Zinc oxide" 0.30 0.30 0. 30 0. 30 011 No. 5.--- 1.00 1. 00 1. 00 1. 00 TABLE X Nut meal (fine)- 5.00 5.00 5.00 5.00 Wheat flour 2. 00 2.00 2. 00 2. 00 Parts y w lg t Flake aluminum (-325 mesh) 1.50 2. 00 2.50 3.00

Example Number 35 36 37 38 Total 100.00 100.00 100.00 100.00

Composition: Test results:

Trimethylolethane trimtrate 14. 00 1 00 1 00 00 Sand density (g./cc.) 1. 15 1. 11 1. 11 1. 11 Ammonium nitrategrained 42.10 51.60 61.10 65.60 sti k Weight, (1% i h x 8 Sodium nitrate.-- 35. 00 25. 00 15- 00 0- 0 inches) 155 150 150 150 Zinc oxide-. 0.30 0.30 0.30 0.30 Ballistic pendulum value (No. 6 Oil No. 5 0.10 0.10 0.10 0.10 cap 9.2 10.2 11.1 11.5 Nut meal (fine)... 5. 00 5. 00 5. 00 5. 00 Sensitivity (1 inch x 4inches) (1) (2) (2) Jaguar gual' guJrL. 00 00 00 00 5 Rate of detonation (1% inches x 8 Flake aluminum (325 mesh) 60 2. 00 0 0 inches)(meters/second) 2,210 2,381 2,582 2,787

Total 100 00 100. 00 100. 00 100. 00 1 can 2 %cap.

Test results:

2an% densitty ((g./)cc&)1? 1 1 "a- 1. 19 1. 15 1. 11 1. 11

tic Weig t g. 8 inc es x t Bific qs).- a .l 150 150 70 These formulations had good rates of detonation and 2.1510 811 uum V3118 O. s t iz h h k 1 k?) (1 6); high sens1tlv1ty.

ensi ivity line it inc es I X! Ratclof detonation oy inches x 8 q 542 2 803 2 903 3 028 E MPLE 0 s et. seco ,1 m (m n A trnnethylolethane trlnitrate-mtrocellulose gel was -15 p- 75 prepared by dissolving 4 parts of nitrocellulose (12.5%

1 3 N) in 120 parts of ni-tromethane. To this was added with stirring 16 parts of trimethylolethane trinitrate. The mixture was then spread in a thin layer in a tray, allowing the nitromethane to evaporate, leaving a pliable, clear gel. A gelatin dynamite was prepared from this gel, having the following formulation:

Gel: Percent by weight The ammonium nitrate was brought to 130 F. and mixed hot with the gel. The remaining ingredients were then mixed in. This composition had a good sensitivity, a high density, and a low rate of detonation.

Having regard to the foregoing disclosure, the following is claimed as the inventive and patentable embodiments thereof:

1. A trimethylolethane trinitrate explosive composition having a high rate of detonation and good sensitivity, comprising a mixture of an inorganic nitrate oxidizer, trimethylolethane trinitrate as the sole explosive sensitizer, and particulate aluminum.

2. A trimethylolethane trinitrate explosive composition in accordance with claim 1, in which the inorganic nitrate is ammonium nitrate.

3. A trimethylolethane trinitrate explosive composition in accordance with claim 1 in which the inorganic nitrate is a mixture of ammonium nitrate and sodium nitrate.

4. A trimethylolethane trinitrate explosive composition in accordance with claim 1, in which the inorganic oxidizer is in an amount from about 50 to about 90%, and the trimethylolethane trinitrate is in an amount from about 10 to about 50%.

5. A trimethylolethane trinitrate explosive composition in accordance with claim 4, in the form of an aqueous slurry.

6. A trimethylolethane trinitrate explosive composition in accordance with claim 5 comprising a solid carbona: ceous fuel in an amount from about 0.5 to about 30% of the mixture.

7. A trimethylolethane trinitrate explosive composition in accordance with claim 5 in which the total metal fuel including the aluminum is in an amount from about 0.5 to about 30% of the mixture.

8. A trimethylolethane trinitrate explosive composition in accordance with claim 7 in which the metal fuel is alu- 14 minum having a particle size within the range from -6 to 325 mesh.

9. A trimethylolethane trinitrate explosive composition in accordance with claim 8, in which the aluminum is flake aluminum.

10. A trimethylolethane trinitrate explosive composition in accordance with claim 4 comprising an additional sensitizing explosive selected from the group consisting of dinitrotoluene, trinitrotoluene, an equal parts by weight mixture of pentaerythritol tetranitrate and trinitrotoluene, a mixture of up to cyclorimethylenetrinitramine, up to 40% trinitrotoluene, and 1 to 4% wax, a mixture of up to 60% cyclotrimethylenetrinitramine and up to 40% trinitrotoluene, nitrostarch, trinitrophenylmethylnitramine, smokeless powder, and carbine ball powder in an amount up to about 25% of the total sensitizing explosive.

11. A process for forming a trimethylolethane trinitrate explosive composition having a high rate of detonation and good sensitivity, comprising blending trimethylolethane trinitrate, an inorganic nitrate oxidizer at from to and mixing in particulate aluminum.

12. A process in accordance with claim 11, in which the blending is carried out in the presence of Water, in an amount not exceeding about 1%.

13. A process in accordance with claim 11, wherein the inorganic nitrate is ammonium nitrate.

14. A process in accordance with claim 11, wherein the inorganic nitrate is a mixture of ammonium nitrate and sodium nitrate.

15. A process in accordance with claim 11, which includes blending a solid carbonaceous fuel with the blend of inorganic nitrate and trimethylolethane trinitrate in an amount of from 0.5 to about 30% 16. A process in accordance with claim 11, which includes blending the aluminum in an amount of from 0.5 to about 30%.

17. A process in accordance with claim 11, wherein the blending is continued for from fifteen minutes to onehalf hour.

References Cited UNITED STATES PATENTS 2,821,466 1/1958 Russell 1498 3,344,005 9/1967 Bronstein et a1. 149--88X 3,423,256 1/ 1969 Griflith 149-47X 3,489,623 1/ 1970 Griffith et a1. 14991X BENJAMIN R. PADGETT, Primary Examiner S. I. LECHERT, JR., Assistant Examiner US. Cl. X.R.