RU2627409C1 - Igniter composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: igniter composition contains polyvinyl butyral as a binder, ammonium perchlorate - as an oxidizer, aluminium or the aluminium-magnesium alloy PAM-3 as metal fuel, as well as plasticiser-dibutyl phthalate, technological additives-technical carbon, paraffin, oleic acid, zinc stearate.

EFFECT: improved performance, greater power, combustion temperature and combustion heat.

1 tbl, 5 ex

Description

The invention relates to igniter compositions used to ignite heat-resistant mixtures.

Known shock igniter compositions [1, 2] containing diazodinitrophenol, potassium salt of azidodinitrophenol, tetrazene, ceramics and potassium dinitrobenzofuroxinate, monobasic potassium stifnate, tetrazene, an inert sensitizer. The compositions due to their purpose have a high sensitivity to shock and lack of thermal stability.

Also known compositions: a heat-resistant igniter composition containing fuel - silicon, oxidizing agents - lead minium and lead chromate, a binder - silicon-organic varnish [3] and a heat-resistant igniter composition containing lead thiocyanate, potassium perchlorate and lead chromate [4]. The main disadvantage of the compositions is the presence in the formulations of lead derivatives, which are very toxic compounds.

Closest to the proposed invention is a heat-resistant pyrotechnic composition [5], adopted as a prototype containing a binder - a mixture of a copolymer of butadiene and nitrile of acrylic acid with phenol-formaldehyde resin (15-30 wt.%) And an oxidizing agent - potassium perchlorate (70-85 wt.% )

The disadvantages of the prototype:

- low strength of the composition (317.2-535.7 kJ / kg);

- low combustion temperature (less than 3000 K);

- low heat of combustion (1263.9-2549.5 kJ / kg).

The objective of the invention is to develop an igniter composition with greater strength, a combustion temperature (more than 3000 K) and a heat of combustion to ensure reliable ignition of heat-resistant mixtures with a flash point of 1500 ° C.

The problem is solved due to the fact that the igniter composition containing a binder and an oxidizing agent is characterized in that it contains polyvinyl butyral, an oxidizing agent - ammonium perchlorate, metallic fuel - aluminum or aluminum-magnesium alloy PAM-3, as well as a plasticizer - dibutyl phthalate technological additives - technical carbon, paraffin, oleic acid, zinc stearate in the following ratio of components, wt. %:

polyvinyl butyral 14.5-15.5 aluminum or aluminum-magnesium alloy PAM-3 6.5-5.5 dibutyl phthalate 4.2-4.8 paraffin 0.8-1.2 oleic acid 0.8-1.2 carbon technical 0.4-0.2 ammonium perchlorate 72.8-71.6 zinc stearate (in excess of 100%) 0.4-0.6

With an increase in the binder content above 15.5 wt. % the values of the operating characteristics of the igniter composition are markedly reduced. The increase in the content of oxidizing agent in the composition above 72.8 wt. % will lead to an increase in the energy characteristics of the composition, however, the content of the binder decreases (less than 14.5 wt.%) and, therefore, the strength properties of the composition deteriorate. When the content of the oxidizing agent in the composition is less than 71.6 wt. % decreases the oxygen coefficient α, significantly decreases the values of the operating characteristics of the composition and the content of the products of complete combustion. Metallic fuel provides an increase in the combustion temperature (more than 3000 K) and an increase in the ignition ability of the composition. When the content of metallic fuel is less than 5.5 wt. % there is a decrease in the combustion temperature, respectively, the content of metallic fuel is more than 6.5 wt. % leads to an increase in performance. However, such a composition is difficult and dangerous to process due to the high viscosity of the mass and large external friction with the metal walls of the apparatus. Dibutyl phthalate provides manufacturability of the processing of the mass and mechanical strength of the composition. The content of dibutyl phthalate in the composition of less than 4.2 wt. % will lead to a deterioration in the strength properties of the igniter composition. Technological additives reduce external friction during the process of continuous pressing, reducing their number less than 2.2 wt. % increases the risk of the pressing phase. The characteristics of the prototype, the proposed composition and composition outside the boundary conditions are shown in the table.

The table shows that the proposed composition (samples 1, 2, 3) compared with the prototype allows to increase performance: approximately 2.5 times the strength, the combustion temperature from 1120.4-2919.4 K to 3002-3100 K, calorific value of about 2.8 times.

With a decrease in the content of oxidizing agent (less than 71.6 wt.%), Metallic fuel (less than 5.5 wt.%) And an increase in the content of the binder (more than 15.5 wt.%) And technological additives (more than 3.4 wt.%) igniter composition performance values are reduced (Sample 5). An increase in the content of oxidizing agent (more than 72.8 wt.%), Metallic fuel (more than 6.5 wt.%) And a decrease in the content of the binder (less than 14.5 wt.%), Technological additives (less than 2.2 wt.%) Leads to increase the strength, combustion temperature and heat of combustion (Sample 4). However, the technology of this composition is very dangerous and time-consuming, in addition, the finished product does not provide sufficient strength properties.

LITERATURE

1. Patent RU 2086523 from 08/10/1997 “Pyrotechnic shock igniter composition for small arms cartridges”, С06В 35, С06В 25/04.

2. Patent RU 2144523 from 01.20.2000 "Pyrotechnic shock ignition composition for ring-shaped cartridges", С06В 35, С06В 25/06.

3. Patent RU 2202528 dated 04/20/2003 "Heat-resistant igniter composition", С06В 33/12, С06В 33/06, С06В 29/02.

4. Patent RU 2238257 dated 10/20/2004 “The composition is igniter heat-resistant”, С06В 33/12, С06С 9/00.

5. Patent RU 2261852 dated 10.10.2005 “Heat-resistant pyrotechnic composition”, С06В 29/02, С06В 45/10.

Claims (2)

An igniter composition containing a binder and an oxidizing agent, characterized in that it contains polyvinyl butyral, an oxidizing agent - ammonium perchlorate, a metal fuel - aluminum or an aluminum-magnesium alloy PAM-3, as well as a plasticizer - dibutyl phthalate, technological additives - industrial carbon, paraffin, oleic acid, zinc stearate in the following ratio of components, wt.%: polyvinyl butyral 14.5-15.5 aluminum or aluminum-magnesium PAM-3 alloy 6.5-5.5 dibutyl phthalate 4.2-4.8 paraffin 0.8-1.2 oleic acid 0.8-1.2 carbon technical 0.4-0.2 ammonium perchlorate 72.8-71.6 zinc stearate (in excess of 100%) 0.4-0.6