Societe Nationale Des Poudres Et Explosifs

Snpe

Alain Lefumeux

Bernard Finck

Christian B Perotto

Serge F Raynal

Bernard Martin

Dominique Wiencek

Bernard Mahe

The invention relates to novel non-detonatable pyrotechnic materials which have a thickness of less than 500 .mu.m or a mass of less than 15 mg, whose combustion is self-sustainable after localized initiation by an electrical power of between 150 mW and 800 mW, for a time of between 20 ms and 600 ms, and which comprise from 25 to 80% by weight of an energy-releasing binder based on poly(glycidyl azide), or on poly(3,3-bis[azidomethyl]oxetane) or on a polyester or polyether and on at least one energy-releasing plasticizer, from 10 to 70% by weight of ammonium perchlorate, the particle size of which is between 0.5 and 30 .mu.m, and from 0% to 45% by weight of at least one nitramine. These novel materials are used as miniature gas generators, miniature propulsion units or miniature heat generators.

Non-detonatable pyrotechnic materials for microsystems

The present invention relates to the field of the continuous manufacture of composite pyrotechnic products. A heat-curable liquid binder (3) is mixed with a thickening filler (4) in a mixer (1) so as to obtain a viscous premix (2) which is unreactive at ambient temperature and which can be subsequently mixed with oxidizing fillers (17) to give, after extrusion and chopping, intermediate products (24) which are not yet crosslinked but which have stable geometrical dimensions. The structure of the products (24) is subsequently set by crosslinking the binder in an oven (26). The invention permits the continuous industrial manufacture in series of small crosslinked composite pyrotechnic charges without any 'pot life' constraint since the binder does not change at ambient temperature.

Continuous process for solvent-free manufacture of heat-curable

Continuous process for the manufacture of thermoformable composite pyrotechnic products comprising at least one thermoplastic or quasi-thermoplastic binder and an organic or inorganic crystalline oxidizing charge, which are mixed and homogenized on a roll mill consisting of two cylindrical rollers of identical length, with parallel axes situated in the same horizontal plane, the rollers turning in opposite directions to each other with different speeds of rotation and their axes being separated from each other so as to allow a minimum separation to exist between the external surfaces of the two rollers in the plane containing the two axes. The binder is introduced continuously into a feed zone situated at one of the ends of the said rollers, in a pre-formulated solid form containing all the constituents of the binder and being free from solvent so that the binder forms a continuous sheet which covers the faster turning roller. The product is withdrawn continuously into a recovery zone situated at the end of the rollers opposite to that where introduction of the binder takes place, the said oxidizing charge is introduced continuously in the form of crystals in a zone situated between the binder feed zone and the recovery zone of the pyrotechnic product and arranged above the roller covered with the binder, the size of the crystals constituting the oxidizing charge being at most equal to the minimum separation existing between the external surfaces of the two rollers. Apparatus for carrying out the process is also disclosed.

Continuous process for the solventless manufacture of composite

The present invention relates to the field of gas-generating pyrotechnic compositions intended for motor vehicle safety. The compositions according to the invention include: an oxygen-containing thermoplastic binder and especially a block aliphatic copolymer of formula: ##STR1## in which: PA is a polyamide block, PE is a polyether block, n is a number between 2 and 10, an energetic plasticizer which is a polyglycidyl azide, an oxidizing charge in which at least 85% of its weight consists of ammonium nitrate. The compositions according to the invention burn without solid residues and can be employed in gas generators without a filter chamber.

Pyrotechnic compositions generating clean and nontoxic gases, containing

The present invention relates to low-vulnerability propellent powders for weapons. The powders according to the invention consist of at least one organic nitro compound and an organic binder and are characterized in that they contain at least one additive chosen from the group consisting of lithium fluoride, ammonium fluoride and lithium nitrate, optionally in the presence of acetylene black. The powders according to the invention exhibit good ignition characteristics while retaining low vulnerability to impacts and to thermal shocks.

Ignition-sensitive low-vulnerability propellent powder

The object of the present invention is novel solid pyrotechnic compositions with a loaded and plasticized thermoplastic binder, which can be used notably as propellants with non-polluting combustion, as propellants with a high combustion rate or as compositions generating non-toxic gases for air-bags. The plasticizer for the binder comprises a polybutadiene having a number average molecular weight of between 1500 and 7500 and having, added to some of its ethylenic non-saturations, silylferrocene groups.

Solid pyrotechnic compositions with a thermoplastic binder and a

The invention relates to a composite material with lubricating properties consisting of a solid polymeric matrix such as polystyrene or polymethyl methacrylate containing between 20 and 85% by weight of a liquid oil with lubricating properties, such as a silicone oil. The material according to the invention is obtained by polymerization of an emulsion of the said oil in a monomer such as styrene or methyl methacrylate monomer in the presence of a surface-active agent which is a two- or three-block block copolymer in which one repeat unit is compatible with the said monomer. The materials according to the invention are used to form antierosive components for ammunition intended for barrel weapon systems and in particular wads (8) for shells (1).

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Orsay, France

Alain Lefumeux