US3786751A - Pressure sensitive mine insensitive to water deactivation - Google Patents
Pressure sensitive mine insensitive to water deactivation Download PDFInfo
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- US3786751A US3786751A US00362721A US3786751DA US3786751A US 3786751 A US3786751 A US 3786751A US 00362721 A US00362721 A US 00362721A US 3786751D A US3786751D A US 3786751DA US 3786751 A US3786751 A US 3786751A
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- United States
- Prior art keywords
- group
- water
- mine
- explosive
- silane
- Prior art date
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title abstract description 43
- 230000009849 deactivation Effects 0.000 title abstract description 5
- 239000002360 explosive Substances 0.000 claims abstract description 47
- 239000000203 mixture Substances 0.000 claims abstract description 46
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 claims abstract description 31
- 229910000077 silane Inorganic materials 0.000 claims abstract description 31
- 150000008282 halocarbons Chemical class 0.000 claims abstract description 18
- 150000001540 azides Chemical class 0.000 claims abstract description 7
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000007800 oxidant agent Substances 0.000 claims abstract description 7
- VKJKEPKFPUWCAS-UHFFFAOYSA-M potassium chlorate Chemical compound [K+].[O-]Cl(=O)=O VKJKEPKFPUWCAS-UHFFFAOYSA-M 0.000 claims abstract description 7
- SJECZPVISLOESU-UHFFFAOYSA-N 3-trimethoxysilylpropan-1-amine Chemical compound CO[Si](OC)(OC)CCCN SJECZPVISLOESU-UHFFFAOYSA-N 0.000 claims abstract description 6
- -1 Beta aminoethyl Chemical group 0.000 claims abstract description 6
- 239000005337 ground glass Substances 0.000 claims abstract description 6
- AJDIZQLSFPQPEY-UHFFFAOYSA-N 1,1,2-Trichlorotrifluoroethane Chemical compound FC(F)(Cl)C(F)(Cl)Cl AJDIZQLSFPQPEY-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000000178 monomer Substances 0.000 claims description 19
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 claims description 6
- CYTYCFOTNPOANT-UHFFFAOYSA-N Perchloroethylene Chemical group ClC(Cl)=C(Cl)Cl CYTYCFOTNPOANT-UHFFFAOYSA-N 0.000 claims description 4
- 125000003545 alkoxy group Chemical group 0.000 claims description 4
- 125000004104 aryloxy group Chemical group 0.000 claims description 4
- 150000002367 halogens Chemical class 0.000 claims description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 4
- 229950011008 tetrachloroethylene Drugs 0.000 claims description 4
- TZRXHJWUDPFEEY-UHFFFAOYSA-N Pentaerythritol Tetranitrate Chemical compound [O-][N+](=O)OCC(CO[N+]([O-])=O)(CO[N+]([O-])=O)CO[N+]([O-])=O TZRXHJWUDPFEEY-UHFFFAOYSA-N 0.000 claims description 3
- 125000003282 alkyl amino group Chemical group 0.000 claims description 3
- 125000000217 alkyl group Chemical group 0.000 claims description 3
- 125000004103 aminoalkyl group Chemical group 0.000 claims description 3
- 125000005001 aminoaryl group Chemical group 0.000 claims description 3
- 125000001769 aryl amino group Chemical group 0.000 claims description 3
- 125000003118 aryl group Chemical group 0.000 claims description 3
- GNEPOXWQWFSSOU-UHFFFAOYSA-N dichloro-methyl-phenylsilane Chemical compound C[Si](Cl)(Cl)C1=CC=CC=C1 GNEPOXWQWFSSOU-UHFFFAOYSA-N 0.000 claims description 3
- LIKFHECYJZWXFJ-UHFFFAOYSA-N dimethyldichlorosilane Chemical compound C[Si](C)(Cl)Cl LIKFHECYJZWXFJ-UHFFFAOYSA-N 0.000 claims description 3
- 229910052736 halogen Inorganic materials 0.000 claims description 3
- 239000005054 phenyltrichlorosilane Substances 0.000 claims description 3
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 claims description 3
- ORVMIVQULIKXCP-UHFFFAOYSA-N trichloro(phenyl)silane Chemical compound Cl[Si](Cl)(Cl)C1=CC=CC=C1 ORVMIVQULIKXCP-UHFFFAOYSA-N 0.000 claims description 3
- CPUDPFPXCZDNGI-UHFFFAOYSA-N triethoxy(methyl)silane Chemical compound CCO[Si](C)(OCC)OCC CPUDPFPXCZDNGI-UHFFFAOYSA-N 0.000 claims description 3
- WYTZZXDRDKSJID-UHFFFAOYSA-N (3-aminopropyl)triethoxysilane Chemical compound CCO[Si](OCC)(OCC)CCCN WYTZZXDRDKSJID-UHFFFAOYSA-N 0.000 claims description 2
- 239000004215 Carbon black (E152) Substances 0.000 claims description 2
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 claims description 2
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 2
- 239000005977 Ethylene Substances 0.000 claims description 2
- FQEKAFQSVPLXON-UHFFFAOYSA-N butyl(trichloro)silane Chemical compound CCCC[Si](Cl)(Cl)Cl FQEKAFQSVPLXON-UHFFFAOYSA-N 0.000 claims description 2
- KVBKAPANDHPRDG-UHFFFAOYSA-N dibromotetrafluoroethane Chemical compound FC(F)(Br)C(F)(F)Br KVBKAPANDHPRDG-UHFFFAOYSA-N 0.000 claims description 2
- AXZAYXJCENRGIM-UHFFFAOYSA-J dipotassium;tetrabromoplatinum(2-) Chemical compound [K+].[K+].[Br-].[Br-].[Br-].[Br-].[Pt+2] AXZAYXJCENRGIM-UHFFFAOYSA-J 0.000 claims description 2
- 229930195733 hydrocarbon Natural products 0.000 claims description 2
- 150000002430 hydrocarbons Chemical class 0.000 claims description 2
- 229910001487 potassium perchlorate Inorganic materials 0.000 claims description 2
- UGCSPKPEHQEOSR-UHFFFAOYSA-N 1,1,2,2-tetrachloro-1,2-difluoroethane Chemical compound FC(Cl)(Cl)C(F)(Cl)Cl UGCSPKPEHQEOSR-UHFFFAOYSA-N 0.000 claims 1
- 239000007788 liquid Substances 0.000 abstract description 26
- 239000011248 coating agent Substances 0.000 abstract description 12
- 238000000576 coating method Methods 0.000 abstract description 12
- 238000000034 method Methods 0.000 abstract description 11
- 239000002904 solvent Substances 0.000 abstract description 7
- 238000006116 polymerization reaction Methods 0.000 abstract description 5
- 238000001704 evaporation Methods 0.000 abstract description 4
- 230000008020 evaporation Effects 0.000 abstract description 4
- 239000000446 fuel Substances 0.000 abstract description 2
- 229920000642 polymer Polymers 0.000 description 8
- 238000000586 desensitisation Methods 0.000 description 6
- 238000012360 testing method Methods 0.000 description 5
- 125000000022 2-aminoethyl group Chemical group [H]C([*])([H])C([H])([H])N([H])[H] 0.000 description 4
- 239000002002 slurry Substances 0.000 description 4
- 125000001424 substituent group Chemical group 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- UJPMYEOUBPIPHQ-UHFFFAOYSA-N 1,1,1-trifluoroethane Chemical compound CC(F)(F)F UJPMYEOUBPIPHQ-UHFFFAOYSA-N 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229920000573 polyethylene Polymers 0.000 description 3
- 150000004756 silanes Chemical class 0.000 description 3
- NPNPZTNLOVBDOC-UHFFFAOYSA-N 1,1-difluoroethane Chemical compound CC(F)F NPNPZTNLOVBDOC-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical group [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 239000012298 atmosphere Substances 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000005474 detonation Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 230000002028 premature Effects 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- 238000009877 rendering Methods 0.000 description 2
- SCPYDCQAZCOKTP-UHFFFAOYSA-N silanol Chemical compound [SiH3]O SCPYDCQAZCOKTP-UHFFFAOYSA-N 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- APQIUTYORBAGEZ-UHFFFAOYSA-N 1,1-dibromoethane Chemical compound CC(Br)Br APQIUTYORBAGEZ-UHFFFAOYSA-N 0.000 description 1
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 1
- 238000005773 Enders reaction Methods 0.000 description 1
- KMYUUNBBYWAVME-UHFFFAOYSA-N [ClH]1[ClH]CC=C1 Chemical compound [ClH]1[ClH]CC=C1 KMYUUNBBYWAVME-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 229920005565 cyclic polymer Polymers 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- KPUWHANPEXNPJT-UHFFFAOYSA-N disiloxane Chemical class [SiH3]O[SiH3] KPUWHANPEXNPJT-UHFFFAOYSA-N 0.000 description 1
- 229910021485 fumed silica Inorganic materials 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- JEGUKCSWCFPDGT-UHFFFAOYSA-N h2o hydrate Chemical compound O.O JEGUKCSWCFPDGT-UHFFFAOYSA-N 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 230000003301 hydrolyzing effect Effects 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- WETZJIOEDGMBMA-UHFFFAOYSA-L lead styphnate Chemical compound [Pb+2].[O-]C1=C([N+]([O-])=O)C=C([N+]([O-])=O)C([O-])=C1[N+]([O-])=O WETZJIOEDGMBMA-UHFFFAOYSA-L 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000007793 non-solvation Methods 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 125000000962 organic group Chemical group 0.000 description 1
- VLTRZXGMWDSKGL-UHFFFAOYSA-M perchlorate Inorganic materials [O-]Cl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-M 0.000 description 1
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 1
- 238000006068 polycondensation reaction Methods 0.000 description 1
- 239000005297 pyrex Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000002562 thickening agent Substances 0.000 description 1
- QQQSFSZALRVCSZ-UHFFFAOYSA-N triethoxysilane Chemical compound CCO[SiH](OCC)OCC QQQSFSZALRVCSZ-UHFFFAOYSA-N 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
- F42C3/00—Fuzes actuated by exposure to a liquid, e.g. seawater
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
- F42C14/00—Mechanical fuzes characterised by the ammunition class or type
- F42C14/08—Mechanical fuzes characterised by the ammunition class or type for land mines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
- F42C15/00—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42C—AMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
- F42C15/00—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
- F42C15/28—Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges operated by flow of fluent material, e.g. shot, fluids
Definitions
- ABSTRACT A pressure sensitive explosive composition is provided which is rendered insensitive to water or water vapor by means of a coating of an organo-functional silane capable of polymerization on contact with water or water vapor. Additionally, a method is provided of coating such a composition by the use of the abovementioned silane in a halocarbon solvent having a relatively low vapor pressure at ambient conditions.
- the composition may be a mixture of an inorganic oxidizer and fuel such as potassium chlorate, red phosphorous and ground glass or a mixture of a primary explosive such as lead azide and a secondary explosive such as RDX, either mixture being coated with a silane such as 7(B aminoethyl) aminopropyl trimethoxy silane applied from a volatile halocarbon liquid such as 1,1,2 trichlorol ,2,2 trifluoro ethane.
- a silane such as 7(B aminoethyl) aminopropyl trimethoxy silane applied from a volatile halocarbon liquid such as 1,1,2 trichlorol ,2,2 trifluoro ethane.
- Another object is to furnish a method of rendering an explosive composition insensitive to moisture.
- a further object is to provide a moisture insensitive, pressure sensitive, explosive composition for use in antipersonnel mines.
- this coating provides a means of making the explosive or pyrotechnic composition insensitive to moisture. I have also found that this polymer coating does not interfere with the pressure sensitivity necessary to ultimately activate a mine.
- my invention need not be used exclusively with a mine, it may be used with any compatible explosive or pyrotechnic composition which must be protected from moisture either vapor or liquid.
- the solvent liquid used with my invention must be capable of dissolving the silane monomer and additionally possess the properties of non-reactivity and nonsolvation with the explosive, non-reactivity with the organo-functional silane monomer and a vapor pressure, such that the liquid will evaporate in a relatively short time at ambient temperatures, thus in effect resulting in a reversibly desensitized mine. Additionally, if my invention is to be used with the type of mine described, the liquid solvent must be capable of desensitizing the explosive or pyrotechnic while the explosive is still thoroughly wetted by the liquid. Any liquid which will meet these critera can be used.
- halocarbons of a chain length of one or two carbon atoms containing at least one halogen substituent are preferable, for example Freon l 13 or perchloroethylene. These halocarbons preferably have a boiling point between about 30C and about C.
- Other preferred halocarbons are 1,1,2 trichloro-l,2,2 trifluoroethane; l,l,2,2 tetrachloro-l,2 difluoroethane; l,1,2,2 tetrafluoro-1,2 dibromoethane; carbon tetrachloride and tetrachloroethylene.
- organo-functional silane when it is a liquid of sufficiently low viscosity, it can be readily mixed with the explosive and it will not be necessary to use a desensitizing liquid. This procedure, although effective is not preferred because of attendant hazardous mixing conditions.
- My invention can be utilized for protection of any solid explosive composition susceptible to desensitization by moisture, for example: mixtures of red phosphorous, a strong inorganic oxidizer such as potassium chlorate or perchlorate and ground glass and pressure sensitive mixtures of primary explosives such as lead azide or lead styphnate and secondary explosives such as RDX, PETN or l-IMX.
- My invention utilizes organo-functional silane monomers capable of reacting with moisture at atmospheric temperatures to form a water impermeable polymer.
- the monomer must be soluble in the desensitization liquid and adhere strongly to the solid explosive or pyrotechnic substrate. This is usually accomplished either during the immersion of the substrate in the liquid or upon substantial volatilization of the liquid thus leaving a monomeric coating. Additionally, the monomer must be capable of forming a moisture impervious coating of polymer upon contact with water or water vapor. Further, the coating must not prevent initiation of the explosive.
- the total amount of silane monomer used will depend on the amount of surface area of explosive substrate because a complete coating is desired. Additionally, the amount used must not be enough to cause excessive desensitization.
- Organo-functional silanes capable of use with my invention are well known and can be represented by the general formula.
- Si represents a silicon atom
- at least one of the R substituents is selected from the group consisting of halogen, amino, alkoxyand aryloxy and R represents a substituent selected from the group consisting of alkyl, aryl, aminoalkyl, aminoaryl, alkylamino, arylamino, alkoxy and aryloxy and n is an integer from 1 to 3 inclusive.
- the reaction of such an organo-functional silane to effect protection against moisture for the composition of my invention is thought to be a hydrolytic polycondensation which is believed to proceed largely as follows:
- the silanol product of reaction (1) is unstable and reacts further to form a polymeric silicon containing material. In some cases a siloxane is formed, in other cases a cyclic polymer and in yet others a polyorganosiloxane.
- the type of polymer formed depends upon the type and number of the R and R substituents. R is selected for its ability to hydrolyze to form the necessary intermediate silanol and R is selected for its ability to lend water impermeability to the formed polymer. Generally, where R is alkoxy it will be a short chain, i.e., from one to four carbon atoms. Additionally, the polymerization rate also depends on the substituents selected. Since the purpose of my invention is broadly to provide protection against water and water vapor, the polymerization rate should be relatively rapid upon contact with water or water vapor.
- silanes that may be used with my invention, follow: y(B aminoethyl) aminopropyl trimethoxy silane; 'yaminopropyl triethoxysilane; methyl triethoxysilane; phenyltrichlorosilane; nbutyltrichlorosilane; dimethyl dichlorosilane and methyl phenyldichlorosilane.
- catalysts which are soluble in the liquid used as a desensitizing solvent may be added to insure polymerization of the monomer if they are compatible with the ultimate function of the explosive or pyrotechnic composition.
- EXAMPLE 1 A one percent solution of y (/3 aminoethyl) aminopropyl trimethoxy silane in 10 cc. of 1,1,2 trichloro- 1,2,2 trifluoro ethane was prepared under dry conditions. 0.2 gram of fumed silica thickening agent and then 5 grams of potassium chlorate were added to the solution with agitation. 2 grams of red phosphorous were then added and the resulting desensitized slurry was agitated until homogeneous. 1 gram of cut pyrex glass was added to a small polyethylene* cup under dry conditions and dampened with 1,1,2 trichloro- 1 ,2,2 trifluoro ethane. 3 grams of the desensitized slurry was added to the cup and then the cup was closed with a rigid polyethylene disc and heat sealed. The cup was conditioned at a specified temperature and relative humidity and subsequently tested for effectiveness by standard tests.
- the polyethylene cup and disc were made from Alathon A 3120 film (a registered trademark of E. l. DuPont de Nemours Co.), this product, marketed by DuPont, was found suitable for the present application.
- EXAMPLE 2 Using the same procedure as in Example 1, but in place of the potassium chlorate, red phosphorous and ground glass, enough RDX and lead azide is introduced into the halocarbon, silane, silica slurry to form a final mixture containing 60 parts by weight of RDX to 40 parts by weight of lead azide.
- Example l Ten of the cups were prepared by the method of Example l, and allowed tostand at ambient temperature and humidity until the solvent was removed by evaporation. After a predetermined time five of the cups were detonated and the pressure required to cause detonation was recorded. The pressure required to initiate the detonation of the cups fell' between 6 and 8 psi which compared favorably with control cups identically prepared without the silane additive. The remaining five cups were placed in a percent relative humidity chamber at room temperature for humidity testing. Two cups were removed after 7 days and tested; one of the cups detonated at 6 psi, the other required 16 psi. Three cups were removed after 14 days in the chamber and tested; one of the cups detonated at 9 psi, the other two required 38 psi and 40 psi respectively.
- a reversibly desensitized antipersonnel mine comprising:
- halocarbon is a halogenated hydrocarbon and said hydrocarbon is selected from the group consisting of methane,
- halocarbon is selected from the group consisting of 1,1,2 trichloro-l ,2,2 trifluoroethane; l,l,2,2 tetrachloro-l ,2 difluoroethane; l,l,2,2 tetrafluoro-l ,2 dibromoethane; carbon tetrachloride and tetrachloroethylene.
- said explosive composition is selected from the group consisting of a mixture of an inorganic oxidizer, red phosphorous and ground glass and a mixture of a primary explosive selected from the group consisting of lead azide and lead syphnate and a secondary explosive selected from the group consisting of RDX, PETN andVHMX.
- a mine as defined in claim 4 wherein said inorganic oxidizer is selected from the group consisting of potassium chlorate and potassium perchlorate.
- organo functional silane monomer has the general formula wherein R is a radical selected from the group consisting of halogen, amino, alkoxy and aryloxy, R is a radical selected from the group consisting of alkyl, aryl, aminoalkyl, aminoaryl, alkylamino and arylamino, and n is an integer from 1 to 3 inclusive.
- organofunctional silane monomer is selected from the group consisting of 'y (/3 aminoethyl) aminopropyl trimethoxy silane, 'y aminopropyl triethoxy silane, methyl triethoxysilane, phenyltrichlorosilane, n-butyl trichlorosilane, dimethyl dichlorosilane and methyl phenyl dichlorosilane.
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
Abstract
A pressure sensitive explosive composition is provided which is rendered insensitive to water or water vapor by means of a coating of an organo-functional silane capable of polymerization on contact with water or water vapor. Additionally, a method is provided of coating such a composition by the use of the abovementioned silane in a halocarbon solvent having a relatively low vapor pressure at ambient conditions. The composition may be a mixture of an inorganic oxidizer and fuel such as potassium chlorate, red phosphorous and ground glass or a mixture of a primary explosive such as lead azide and a secondary explosive such as RDX, either mixture being coated with a silane such as gamma ( Beta aminoethyl) aminopropyl trimethoxy silane applied from a volatile halocarbon liquid such as 1,1,2 trichloro-1,2,2 trifluoro ethane. The silane, after evaporation of the liquid, coats the composition and polymerizes on contact with water or water vapor to form a water impermeable film and this renders the composition insensitive to water deactivation.
Description
United States Patent 91 Seals [451 Jan. 22, 1974 PRESSURE SENSITIVE MINE INSENSITIVE TO WATER DEACTIVATION William O. Seals, Budd Lake Heights, NJ.
22 Filed: May 22,1973
21 Appl. No.: 362,721
Related U.S. Application Data [62] Division of Ser. No. 226,545, Feb. 15, 1972.
[75] Inventor:
[52] U.S. Cl. 102/8, 102/7.2 [51] Int. Cl. F42b 23/14 [58] Field of Search 102/72, 8
[56] References Cited UNITED STATES PATENTS R27,025 1/1971 McDonald 149/11 X 2,368,310 1/1945 Lecky et a1. 102/8 UX 2,999,744 9/1961 Eckels 149/19 3,138,100 6/1964 Peschko 102/8 3,190,775 6/1965 Ender 149/8 3,667,387 6/1972 Picard et al..... 102/8 3,738,276 6/1973 Picard et a1 102/72 Primary Examiner-Carl D. Quarforth Assistant ExaminerE. A. Miller Attorney, Agent, or F irm-Edward J. Kelly; Herbert Ber]; A. Vector Erkkila [5 7] ABSTRACT A pressure sensitive explosive composition is provided which is rendered insensitive to water or water vapor by means of a coating of an organo-functional silane capable of polymerization on contact with water or water vapor. Additionally, a method is provided of coating such a composition by the use of the abovementioned silane in a halocarbon solvent having a relatively low vapor pressure at ambient conditions. The composition may be a mixture of an inorganic oxidizer and fuel such as potassium chlorate, red phosphorous and ground glass or a mixture of a primary explosive such as lead azide and a secondary explosive such as RDX, either mixture being coated with a silane such as 7(B aminoethyl) aminopropyl trimethoxy silane applied from a volatile halocarbon liquid such as 1,1,2 trichlorol ,2,2 trifluoro ethane. The silane, after evaporation of the liquid, coats the composition and polymerizes on contact with water or water vapor to form a water impermeable film and this renders the composition insensitive to water deactivation.
7 Claims, No Drawings PRESSURE SENSITIVE MINE INSENSITIVE TO WATER DEACTIVATION BACKGROUND OF THE INVENTION For certain battlefield applications, it is desirable to deploy a largenumber of packaged explosives over a pre-selected area of the battlefield. Aircraft dispersal is the most convenient method of deployment. This type of dispersal requires maintenance of the packages in a substantially insensitive state until after they hit the ground. An effective, economical method for fabrication of these packages is accomplished by placing the explosive in a vapor permeable container and filling the container with a desensitizing liquid, which will permeatexthe container. After the package is deployed the liquid will evaporate through the container and leave the enclosed explosive armed. One of the principal drawbacks of this type of system is the possibility of premature desensitization of the explosive by water or water vapor. For example, rainfall will cause moisture permeation of the package and permanently desensitize the explosive before it can effectively function. Additionally, a very humid atmosphere has a strong tendency to effect premature complete desensitization due to permeation of the packageby water vapor.
The difficulty thus encountered is of relatively recent originand although many organic compounds, including silanes and siloxanes have been used for various purposes with energetic components (see for example U. S. Pat. Nos. 3,551,222; 3,404,061; 3,058,858; 3,190,775; 3,190,776 and 3,110,638), these uses were neither analogous to the instant problem nor indicative of a solution thereto.
It is, therefore, an object of this invention to provide an; explosive composition which is insensitive to moisture.
Another object is to furnish a method of rendering an explosive composition insensitive to moisture.
A further object is to provide a moisture insensitive, pressure sensitive, explosive composition for use in antipersonnel mines.
Other objects and many of the attendant advantages of thislinvention will be readily appreciated as the same become better understood by reference to th following description, wherein it, is shown that the abovementioned objects are attained and the prior art deficiencies are overcome by the use of an organofunctional silane monomer in a solvent solution to coat allof the components of an explosive composition and thus render the composition insensitive to water vapor, or water.
DESCRIPTION OF A PREFERRED EMBODIMENT Certain types of mines have been used which are dispersed over a preselected area of a battlefield by air drop. These mines must be maintained in an insensitive condition until they hit the ground. One advantageous method of accomplishing this is by using a pressure sensitive explosive or pyrotechnic composition immersed in a desensitizing liquid, the whole being enclosed in a container which is permeable to the vapor of the desensitizing liquid. By the use of this method the mines could be deployed while insensitive and then become armed through the evaporation of the desensitizing liq uid. On standing in a human atmosphere or in a rainstorm, the contained explosive or pyrotechnic tended to become inert because of sorption of water vapor or actual inundation by rain water. I have found that by adding a soluble, organo-functional silane monomer, which polymerizes on contact with water vapor, to the desensitizing liquid and by intimately mixing the resultant solution with the selected explosive or pyrotechnic composition, a mixture is formed which will leave a coating of silane monomer on the explosive composition when the desensitizing liquid volatilizes on standing. Since the monomer polymerizes on contact with water vapor and since the polymer thus formed is not permeable to water or water vapor, this coating provides a means of making the explosive or pyrotechnic composition insensitive to moisture. I have also found that this polymer coating does not interfere with the pressure sensitivity necessary to ultimately activate a mine.
Indeed, my invention need not be used exclusively with a mine, it may be used with any compatible explosive or pyrotechnic composition which must be protected from moisture either vapor or liquid.
The solvent liquid used with my invention must be capable of dissolving the silane monomer and additionally possess the properties of non-reactivity and nonsolvation with the explosive, non-reactivity with the organo-functional silane monomer and a vapor pressure, such that the liquid will evaporate in a relatively short time at ambient temperatures, thus in effect resulting in a reversibly desensitized mine. Additionally, if my invention is to be used with the type of mine described, the liquid solvent must be capable of desensitizing the explosive or pyrotechnic while the explosive is still thoroughly wetted by the liquid. Any liquid which will meet these critera can be used.
It has been found that halocarbons of a chain length of one or two carbon atoms containing at least one halogen substituent are preferable, for example Freon l 13 or perchloroethylene. These halocarbons preferably have a boiling point between about 30C and about C. Other preferred halocarbons are 1,1,2 trichloro-l,2,2 trifluoroethane; l,l,2,2 tetrachloro-l,2 difluoroethane; l,1,2,2 tetrafluoro-1,2 dibromoethane; carbon tetrachloride and tetrachloroethylene. Additionally, when the organo-functional silane is a liquid of sufficiently low viscosity, it can be readily mixed with the explosive and it will not be necessary to use a desensitizing liquid. This procedure, although effective is not preferred because of attendant hazardous mixing conditions. My invention can be utilized for protection of any solid explosive composition susceptible to desensitization by moisture, for example: mixtures of red phosphorous, a strong inorganic oxidizer such as potassium chlorate or perchlorate and ground glass and pressure sensitive mixtures of primary explosives such as lead azide or lead styphnate and secondary explosives such as RDX, PETN or l-IMX.
My invention utilizes organo-functional silane monomers capable of reacting with moisture at atmospheric temperatures to form a water impermeable polymer. The monomer must be soluble in the desensitization liquid and adhere strongly to the solid explosive or pyrotechnic substrate. This is usually accomplished either during the immersion of the substrate in the liquid or upon substantial volatilization of the liquid thus leaving a monomeric coating. Additionally, the monomer must be capable of forming a moisture impervious coating of polymer upon contact with water or water vapor. Further, the coating must not prevent initiation of the explosive. The total amount of silane monomer used will depend on the amount of surface area of explosive substrate because a complete coating is desired. Additionally, the amount used must not be enough to cause excessive desensitization. l have found that between about 1 percent and percent by weight of monomer, based on the amount of explosive or pyrotechnic substrate, will give satisfactory results. 2 percent by weight is preferred. Organo-functional silanes capable of use with my invention are well known and can be represented by the general formula.
wherein Si represents a silicon atom, at least one of the R substituents is selected from the group consisting of halogen, amino, alkoxyand aryloxy and R represents a substituent selected from the group consisting of alkyl, aryl, aminoalkyl, aminoaryl, alkylamino, arylamino, alkoxy and aryloxy and n is an integer from 1 to 3 inclusive. Generally, the reaction of such an organo-functional silane to effect protection against moisture for the composition of my invention is thought to be a hydrolytic polycondensation which is believed to proceed largely as follows:
wherein R, R anTd n have the aforementioned definitions. The silanol product of reaction (1) is unstable and reacts further to form a polymeric silicon containing material. In some cases a siloxane is formed, in other cases a cyclic polymer and in yet others a polyorganosiloxane. The type of polymer formed depends upon the type and number of the R and R substituents. R is selected for its ability to hydrolyze to form the necessary intermediate silanol and R is selected for its ability to lend water impermeability to the formed polymer. Generally, where R is alkoxy it will be a short chain, i.e., from one to four carbon atoms. Additionally, the polymerization rate also depends on the substituents selected. Since the purpose of my invention is broadly to provide protection against water and water vapor, the polymerization rate should be relatively rapid upon contact with water or water vapor.
Some examples of silanes that may be used with my invention, follow: y(B aminoethyl) aminopropyl trimethoxy silane; 'yaminopropyl triethoxysilane; methyl triethoxysilane; phenyltrichlorosilane; nbutyltrichlorosilane; dimethyl dichlorosilane and methyl phenyldichlorosilane.
in certain cases catalysts which are soluble in the liquid used as a desensitizing solvent may be added to insure polymerization of the monomer if they are compatible with the ultimate function of the explosive or pyrotechnic composition.
The method and composition of this invention, which may be used to produce a safe desensitized explosive item having the properties desired, are set forth in the following examples. It is, of course, understood that these examples are meant to be illustrative and not restrictive of my invention.
EXAMPLE 1 A one percent solution of y (/3 aminoethyl) aminopropyl trimethoxy silane in 10 cc. of 1,1,2 trichloro- 1,2,2 trifluoro ethane was prepared under dry conditions. 0.2 gram of fumed silica thickening agent and then 5 grams of potassium chlorate were added to the solution with agitation. 2 grams of red phosphorous were then added and the resulting desensitized slurry was agitated until homogeneous. 1 gram of cut pyrex glass was added to a small polyethylene* cup under dry conditions and dampened with 1,1,2 trichloro- 1 ,2,2 trifluoro ethane. 3 grams of the desensitized slurry was added to the cup and then the cup was closed with a rigid polyethylene disc and heat sealed. The cup was conditioned at a specified temperature and relative humidity and subsequently tested for effectiveness by standard tests.
The polyethylene cup and disc were made from Alathon A 3120 film (a registered trademark of E. l. DuPont de Nemours Co.), this product, marketed by DuPont, was found suitable for the present application.
EXAMPLE 2 Using the same procedure as in Example 1, but in place of the potassium chlorate, red phosphorous and ground glass, enough RDX and lead azide is introduced into the halocarbon, silane, silica slurry to form a final mixture containing 60 parts by weight of RDX to 40 parts by weight of lead azide.
RESULTS Ten of the cups were prepared by the method of Example l, and allowed tostand at ambient temperature and humidity until the solvent was removed by evaporation. After a predetermined time five of the cups were detonated and the pressure required to cause detonation was recorded. The pressure required to initiate the detonation of the cups fell' between 6 and 8 psi which compared favorably with control cups identically prepared without the silane additive. The remaining five cups were placed in a percent relative humidity chamber at room temperature for humidity testing. Two cups were removed after 7 days and tested; one of the cups detonated at 6 psi, the other required 16 psi. Three cups were removed after 14 days in the chamber and tested; one of the cups detonated at 9 psi, the other two required 38 psi and 40 psi respectively.
These results indicate that there is no apparent desensitization of the explosive by the addition of silane as shown by the comparability of the pressure required to detonate the test cups and the pressure required to detonate control cups prepared without silane. Additionally, with the 7 day test, since one of the samples was in line with the necessary standard control pressure, the indication is that the silane has provided water vapor protection. The second result which was high may indicate poor coverage by the silane due to inhomogeneity of the original mixture. The test after 14 days indicates the same water vapor protection evident in one of the samples while the other two high results may again indicate inhomogeneity.
Thus, it can be seen that the use of my invention,
, wherein an explosive composition is coated with a water; reactiveorgano-functional silane monomer to prevent detrimental contact of the explosive by moisture, forms the basis for an advance in the art.
I wish it to be understood that I do not desire to be limited to the exactdetails described, for obvious modification will occur to a person skilled in the art.
I claim:
1. A reversibly desensitized antipersonnel mine comprising:
a slurry of a particulate, normally pressure and moisture sensitive explosive composition in a solution of an organo-functional silane monomer, capable of reacting with atmospheric moisture at atmospheric temperatures to form a water impermeable polymer, ina halocarbon liquid capable of desensitizing said explosive composition, said halocarbon having a boiling point between about 30C and 120C, and a sealed container enveloping said slurry, said container, being vapor permeable to both atmospheric moisture and said halocarbon liquid, whereby on deployment of said mine said halocarbon liquid evaporates through said permeable container and deposits a coating of said silane monomer on said particulate explosive composition, and atmospheric moisture enters through said permeable container and reacts with said silane to form a water impermeable polymer rendering said normally pressure sensitive explosive composition insensitive to moisture.
2. A mine as defined in claim 1 wherein said halocarbon is a halogenated hydrocarbon and said hydrocarbon is selected from the group consisting of methane,
ethane and ethylene.
3. A mine as defined in claim 2 wherein said halocarbon is selected from the group consisting of 1,1,2 trichloro-l ,2,2 trifluoroethane; l,l,2,2 tetrachloro-l ,2 difluoroethane; l,l,2,2 tetrafluoro-l ,2 dibromoethane; carbon tetrachloride and tetrachloroethylene.
4. A mine as defined in claim 1, wherein said explosive composition is selected from the group consisting of a mixture of an inorganic oxidizer, red phosphorous and ground glass and a mixture of a primary explosive selected from the group consisting of lead azide and lead syphnate and a secondary explosive selected from the group consisting of RDX, PETN andVHMX.
5. A mine as defined in claim 4 wherein said inorganic oxidizer is selected from the group consisting of potassium chlorate and potassium perchlorate.
6. A mine as defined in claim 1 wherein said organo functional silane monomer has the general formula wherein R is a radical selected from the group consisting of halogen, amino, alkoxy and aryloxy, R is a radical selected from the group consisting of alkyl, aryl, aminoalkyl, aminoaryl, alkylamino and arylamino, and n is an integer from 1 to 3 inclusive.
7. A mine as defined in claim 6 wherein said organofunctional silane monomer is selected from the group consisting of 'y (/3 aminoethyl) aminopropyl trimethoxy silane, 'y aminopropyl triethoxy silane, methyl triethoxysilane, phenyltrichlorosilane, n-butyl trichlorosilane, dimethyl dichlorosilane and methyl phenyl dichlorosilane.
Claims (6)
- 2. A mine as defined in claim 1 wherein said halocarbon is a halogenated hydrocarbon and said hydrocarbon is selected from the group consisting of methane, ethane and ethylene.
- 3. A mine as defined in claim 2 wherein said halocarbon is selected from the group consisting of 1,1,2 trichloro-1,2,2 trifluoroethane; 1,1,2,2 tetrachloro-1,2 difluoroethane; 1,1,2,2 tetrafluoro-1,2 dibromoethane; carbon tetrachloride and tetrachloroethylene.
- 4. A mine as defined in claim 1, wherein said explosive composition is selected from the group consisting of a mixture of an inorganic oxidizer, red phosphorous and ground glass and a mixture of a primary explosive selected from the group consisting of lead azide and lead syphnate and a secondary explosive selected from the group consisting of RDX, PETN and HMX.
- 5. A mine as defined in claim 4 wherein said inorganic oxidizer is selected from the group consisting of potassium chlorate and potassium perchlorate.
- 6. A mine as defined in claim 1 wherein said organo-functional silane monomer has the general formula R(4 n) - Si - R''n wherein R is a radical selected from the group consisting of halogen, amino, alkoxy and aryloxy, R'' is a radical selected from the group consisting of alkyl, aryl, aminoalkyl, aminoaryl, alkylamino and arylamino, and n is an integer from 1 to 3 inclusive.
- 7. A mine as defined in claim 6 wherein said organo-functional silane monomer is selected from the group consisting of gamma ( Beta aminoethyl) aminopropyl trimethoxy silane, gamma aminopropyl triethoxy silane, methyl triethoxysilane, phenyltrichlorosilane, n-butyl trichlorosilane, dimethyl dichlorosilane and methyl phenyl dichlorosilane.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US22654572A | 1972-02-15 | 1972-02-15 | |
| US36272173A | 1973-05-22 | 1973-05-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3786751A true US3786751A (en) | 1974-01-22 |
Family
ID=26920634
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US00362721A Expired - Lifetime US3786751A (en) | 1972-02-15 | 1973-05-22 | Pressure sensitive mine insensitive to water deactivation |
Country Status (1)
| Country | Link |
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| US (1) | US3786751A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080006167A1 (en) * | 2006-07-04 | 2008-01-10 | Diehl Bgt Defence Gmbh & Co., Kg | Blast effect charge |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US27025A (en) * | 1860-01-31 | Improvement in the process of manufacturing steel | ||
| US2368310A (en) * | 1941-01-30 | 1945-01-30 | Lecky Prescott | Explosive and detonating apparatus |
| US2999744A (en) * | 1955-05-06 | 1961-09-12 | Hercules Powder Co Ltd | Plastic explosive compositions |
| US3138100A (en) * | 1960-05-20 | 1964-06-23 | Pennsalt Chemicals Corp | Articles protected against environmental effects |
| US3190775A (en) * | 1960-11-14 | 1965-06-22 | Union Carbide Corp | Treated ammonium nitrate |
| US3667387A (en) * | 1971-01-19 | 1972-06-06 | Us Army | Self-destruct land mine |
| US3738276A (en) * | 1971-11-17 | 1973-06-12 | Us Army | Container with controllably desensitized explosive mixtures |
-
1973
- 1973-05-22 US US00362721A patent/US3786751A/en not_active Expired - Lifetime
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US27025A (en) * | 1860-01-31 | Improvement in the process of manufacturing steel | ||
| US2368310A (en) * | 1941-01-30 | 1945-01-30 | Lecky Prescott | Explosive and detonating apparatus |
| US2999744A (en) * | 1955-05-06 | 1961-09-12 | Hercules Powder Co Ltd | Plastic explosive compositions |
| US3138100A (en) * | 1960-05-20 | 1964-06-23 | Pennsalt Chemicals Corp | Articles protected against environmental effects |
| US3190775A (en) * | 1960-11-14 | 1965-06-22 | Union Carbide Corp | Treated ammonium nitrate |
| US3667387A (en) * | 1971-01-19 | 1972-06-06 | Us Army | Self-destruct land mine |
| US3738276A (en) * | 1971-11-17 | 1973-06-12 | Us Army | Container with controllably desensitized explosive mixtures |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080006167A1 (en) * | 2006-07-04 | 2008-01-10 | Diehl Bgt Defence Gmbh & Co., Kg | Blast effect charge |
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