Production method of nitroguanidine-containing gas production medicine for safety air bag and gas production medicine

Abstract

The invention discloses a production method of a nitroguanidine-containing gas production medicine for an air bag restraint system, which specifically comprises the following steps of: measuring moisture of wet nitroguanidine and calculating feeding weight; screening strontium nitrate; preparing a polyvinyl alcohol solution; feeding the wet nitroguanidine and the fine strontium nitrate into a mixing granulator according to the calculated feeding weight, mixing, adding a polyvinyl alcohol solution, uniformly mixing, granulating to obtain mixed particles, drying, screening, mixing, and pressing to prepare the gas production tablet for the safety airbag. The risk degree and the essence existing in the production process of the gas-producing medicament are reduced; and the production safety of the medicament is improved. The invention further discloses the nitroguanidine-containing gas production medicine for the air bag restraint system, the nitroguanidine-containing gas production medicine is produced by adopting the production method for the nitroguanidine-containing gas production medicine for the air bag restraint system, and the stability of the performance of the gas production medicine is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile passive safety systems, relates to a method for producing a gas generating agent for a safety airbag containing nitroguanidine, and also relates to a gas generating agent for a safety airbag containing nitroguanidine. Background Art

[0002] Conventional charge types for gas generators used in automotive passive safety systems generally include guanidine nitrate-type gas generating agents, 5-aminotetrazole-type gas generating agents, nitroguanidine-type gas generating agents, etc. The common preparation processes of gas generating agents mainly include granulation-pressing molding processes, and common processes include raw material processing, agent mixing, agent granulation, granule drying, auxiliary material mixing, and pressing molding. The Chinese patent "A method for producing a gas generating agent containing nitroguanidine for airbags" (publication date: 2021-07-09, publication number: CN113087582A) involves a preparation process of a nitroguanidine-type gas generating agent, see Figure 1 The production process mainly includes nitroguanidine drying, nitroguanidine ball milling, nitroguanidine screening, strontium nitrate screening, solution preparation, mixed granulation, particle drying and screening, auxiliary material mixing and pressing, a total of 10 processes.

[0003] According to the patent requirements, the moisture content of nitroguanidine after drying is ≤0.10%. In this state, the hazard category of nitroguanidine is 1.1. The moisture content of nitroguanidine entering the factory is 20% to 25%. It needs to be dried before use. There are great safety risks during the drying, transportation, storage and use processes. Summary of the invention

[0004] The purpose of the present invention is to provide a method for producing a gas generating agent for a safety airbag containing nitroguanidine, thereby reducing the risk in the production process of the gas generating agent and substantially improving the production safety of the agent.

[0005] Another object of the present invention is to provide a gas generating agent for a safety airbag containing nitroguanidine, thereby improving the stability of the performance of the gas generating agent.

[0006] The first technical solution adopted by the present invention is a method for producing a gas generating agent for airbags containing nitroguanidine, which is to process nitroguanidine containing 20% ​​to 25% water, i.e., wet nitroguanidine to prepare a gas generating agent for airbags. The gas generating agent for airbags includes a combustible containing nitroguanidine, a water-soluble adhesive, a solvent, an oxidant and auxiliary components. The combustible containing nitroguanidine includes wet nitroguanidine and guanidine nitrate, and the water-soluble adhesive is a polyvinyl alcohol solution. The production method is implemented according to the following steps: Step 1, measuring the moisture content of wet nitroguanidine and calculating the feeding weight; Step 2, screening strontium nitrate to obtain fine strontium nitrate particles; Step 3, preparing a polyvinyl alcohol solution by mixing deionized water and polyvinyl alcohol; Step 4, adding wet nitroguanidine and fine strontium nitrate according to the calculated feeding weight into a mixing granulator for mixing, adding polyvinyl alcohol solution at the same time, mixing evenly and granulating to obtain mixed particles; Step 5, drying the mixed particles to obtain dry mixed particles, screening the dry mixed particles to obtain fine dry mixed particles; Step 6: feed the fine dry mixed particles into a mixer, and add other components of the airbag gas generating agent except nitroguanidine, polyvinyl alcohol and strontium nitrate into the mixer, mix them evenly and press them into a shape to make airbag gas generating agent tablets.

[0007] The first technical solution of the present invention is also characterized in that: Step 1 is to use HS153 infrared moisture analyzer to quickly test the water content of nitroguanidine according to W 湿态称量重量 =W 干态投料重量 / (1-P 湿态硝基胍水分测试结果 ) Calculate the wet nitroguanidine weighing and feed weight.

[0008] In step 2, strontium nitrate is screened by a pneumatic rotary vibrating screen.

[0009] In step 3, the mass ratio of deionized water to polyvinyl alcohol is 2.5-3.75:1.

[0010] After mixing evenly in step 4, granulation is performed using a 10-mesh screen.

[0011] Step 5 uses a boiling dryer to dry the mixed particles. When drying in the boiling dryer, the temperature of the mixed particles is greater than or equal to 50° C., the fan frequency of the boiling dryer is 30 Hz, and the mass content of moisture in the obtained dry mixed particles is less than or equal to 0.1%.

[0012] In step 5, the dry mixed particles are screened through a 24-mesh pneumatic rotary vibrating screen.

[0013] The mixer used in step 6 is a trough mixer, and the rotation speed of the trough mixer is 25r / min.

[0014] Step 6: Tablets are pressed using a 22-punch rotary tablet press.

[0015] The second technical solution adopted by the present invention is that the gas generating agent for safety airbag containing nitroguanidine is produced by the production method of the gas generating agent for safety airbag containing nitroguanidine of the present invention.

[0016] The beneficial effects of the present invention are: The method for producing a gas-generating agent for safety airbags containing nitroguanidine has strong operability and high production efficiency; wet nitroguanidine is fed into the material, and the drying and screening steps of wet nitroguanidine treatment are eliminated, thereby reducing the risk in the agent production process and substantially improving the production safety of the agent; wet nitroguanidine and polyvinyl alcohol solution can be quickly converted into a slurry during the stirring operation of a wet mixing device, thereby reducing dust; the intrinsic safety level and safety protection capability are improved, safe production is guaranteed, accidents such as combustion, explosion, poisoning, etc. are prevented, and occupational hazards are reduced.

[0017] The gas generating agent for safety airbags containing nitroguanidine of the present invention is produced by the production method of the gas generating agent for safety airbags containing nitroguanidine of the present invention, and the agent has stable performance and can be produced efficiently. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of a preparation process of a nitroguanidine type gas-generating agent in the prior art; Figure 2 The present invention is a flow chart of a method for producing a gas generating agent for a safety airbag containing nitroguanidine. DETAILED DESCRIPTION

[0019] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Example 1 The present embodiment provides a method for producing a gas generating agent for airbags containing nitroguanidine, wherein nitroguanidine containing 20% ​​to 25% water, i.e., wet nitroguanidine, is processed to produce a gas generating agent for airbags, wherein the gas generating agent for airbags comprises a combustible containing nitroguanidine, a water-soluble binder, a solvent, an oxidant, and auxiliary components, wherein the combustible containing nitroguanidine comprises wet nitroguanidine and guanidine nitrate, and the water-soluble binder is a polyvinyl alcohol solution, such as Figure 2 As shown, the production method is implemented according to the following steps: Step 1, measuring the moisture content of wet nitroguanidine and calculating the feeding weight; Use HS153 infrared moisture analyzer to quickly test the moisture content of nitroguanidine. According to the dry weight of nitroguanidine specified, according to W 湿态称量重量 =W 干态投料重量 / (1-P 湿态硝基胍水分测试结果 ) Calculate the weighed weight of wet nitroguanidine, i.e., the feed weight; Step 2, screening strontium nitrate through a pneumatic rotary vibrating screen to obtain fine strontium nitrate particles; Step 3, preparing a polyvinyl alcohol solution by mixing deionized water and polyvinyl alcohol, wherein the mass ratio of deionized water to polyvinyl alcohol is 2.5:1; Step 4, adding wet nitroguanidine and fine strontium nitrate according to the calculated feed weight into a mixing granulator for mixing, adding polyvinyl alcohol solution at the same time, mixing evenly, and granulating using a 10-mesh screen to obtain mixed particles; Step 5, drying the mixed particles using a boiling dryer, wherein the temperature of the mixed particles during drying is equal to 50° C., and the fan frequency of the boiling dryer is 30 Hz, to obtain dry mixed particles, wherein the mass content of moisture in the dry mixed particles is 0.1%, and the dry mixed particles are screened through a 24-mesh pneumatic rotary vibrating sieve to obtain fine dry mixed particles; Step 6: feed the fine dry mixed particles into a trough mixer with a rotation speed of 25 r / min, and add other components of the airbag gas generating agent except nitroguanidine, polyvinyl alcohol and strontium nitrate into the mixer. After mixing evenly, use a 22-stroke rotary tablet press to press and form the airbag gas generating agent tablets.

[0021] This embodiment also provides a gas generating agent for safety airbags containing nitroguanidine, which is produced by the method for producing a gas generating agent for safety airbags containing nitroguanidine of this embodiment.

[0022] Example 2 The present embodiment provides a method for producing a gas generating agent for airbags containing nitroguanidine, wherein nitroguanidine containing 20% ​​to 25% water, i.e., wet nitroguanidine, is processed to produce a gas generating agent for airbags, wherein the gas generating agent for airbags comprises a combustible containing nitroguanidine, a water-soluble binder, a solvent, an oxidant, and auxiliary components, wherein the combustible containing nitroguanidine comprises wet nitroguanidine and guanidine nitrate, and the water-soluble binder is a polyvinyl alcohol solution. The production method is implemented according to the following steps: Step 1, measuring the moisture content and calculating the weight of wet nitroguanidine; Use HS153 infrared moisture analyzer to quickly test the moisture content of nitroguanidine. According to the dry weight of nitroguanidine specified, according to W 湿态称量重量 =W 干态投料重量 / (1-P 湿态硝基胍水分测试结果 ) Calculate the weighed weight of wet nitroguanidine, i.e., the feed weight; Step 2, screening strontium nitrate through a pneumatic rotary vibrating screen to obtain fine strontium nitrate particles; Step 3, preparing a polyvinyl alcohol solution by mixing deionized water and polyvinyl alcohol, wherein the mass ratio of deionized water to polyvinyl alcohol is 3.75:1; Step 4, feeding wet nitroguanidine and fine strontium nitrate into a mixing granulator for mixing, adding polyvinyl alcohol solution at the same time, mixing evenly, and granulating using a 10-mesh screen to obtain mixed particles; Step 5, drying the mixed particles using a boiling dryer, wherein the temperature of the mixed particles during drying is 60° C., and the fan frequency of the boiling dryer is 30 Hz, to obtain dry mixed particles, wherein the mass content of moisture in the dry mixed particles is 0.08%, and the dry mixed particles are screened through a 24-mesh pneumatic rotary vibrating sieve to obtain fine dry mixed particles; Step 6: feed the fine dry mixed particles into a trough mixer with a rotation speed of 25 r / min, and add other components of the airbag gas generating agent except nitroguanidine, polyvinyl alcohol and strontium nitrate into the mixer. After mixing evenly, use a 22-stroke rotary tablet press to press and form the airbag gas generating agent tablets.

[0023] This embodiment also provides a gas generating agent for safety airbags containing nitroguanidine, which is produced by the method for producing a gas generating agent for safety airbags containing nitroguanidine of this embodiment.

[0024] Example 3 This embodiment provides a method for producing a gas generating agent for airbags containing nitroguanidine, wherein nitroguanidine containing 23% water, i.e., wet nitroguanidine, is processed to produce a gas generating agent for airbags, wherein the gas generating agent for airbags comprises a combustible containing nitroguanidine, a water-soluble binder, a solvent, an oxidant, and auxiliary components, wherein the combustible containing nitroguanidine comprises wet nitroguanidine and guanidine nitrate, and the water-soluble binder is a polyvinyl alcohol solution. The production method is implemented according to the following steps: Step 1, measuring the moisture content and calculating the weight of wet nitroguanidine; The moisture content of nitroguanidine was quickly tested by HS153 infrared moisture analyzer and found to be 23.00%. According to the dry weight of nitroguanidine specified as 22.00 kg, according to W 湿态称量重量 =W 干态投料重量 / (1-P 湿态硝基胍水分测试结果 ) Calculate the weighing weight of wet nitroguanidine, i.e., the feeding weight, which is 28.6 kg; Step 2, screening strontium nitrate through a pneumatic rotary vibrating screen to obtain fine strontium nitrate particles; Step 3, preparing a polyvinyl alcohol solution by mixing deionized water and polyvinyl alcohol, wherein the mass ratio of deionized water to polyvinyl alcohol is 2.8:1; Step 4, adding 28.6 kg of wet nitroguanidine and fine strontium nitrate into a mixing granulator for mixing, adding polyvinyl alcohol solution at the same time, mixing evenly, and granulating using a 10-mesh screen to obtain mixed particles; Step 5, drying the mixed particles using a boiling dryer, wherein the temperature of the mixed particles during drying is 80° C., and the fan frequency of the boiling dryer is 30 Hz, to obtain dry mixed particles, wherein the mass content of moisture in the dry mixed particles is 0.1%, and the dry mixed particles are screened through a 24-mesh pneumatic rotary vibrating sieve to obtain fine dry mixed particles; Step 6: feed the fine dry mixed particles into a trough mixer with a rotation speed of 25 r / min, and add other components of the airbag gas generating agent except nitroguanidine, polyvinyl alcohol and strontium nitrate into the mixer. After mixing evenly, use a 22-stroke rotary tablet press to press and form the airbag gas generating agent tablets.

[0025] This embodiment also provides a gas generating agent for safety airbags containing nitroguanidine, which is produced by the method for producing a gas generating agent for safety airbags containing nitroguanidine of this embodiment.

[0026] From the above content, it can be seen that the method for producing a gas-generating agent for airbags containing nitroguanidine of the present invention uses an HS153 infrared moisture analyzer to quickly test the water content of nitroguanidine; wet nitroguanidine is fed, and the drying and screening steps of wet nitroguanidine treatment are removed, thereby reducing the risk in the agent production process and substantially improving the production safety of the agent; reducing the transportation and storage of dangerous goods, and at the same time being able to reduce the investment cost of high-energy-consuming equipment and the disposal cost of nitroguanidine cleaning wastewater and waste nitroguanidine from nitroguanidine drying equipment; during the agent mixing process, several materials are quickly converted into a slurry, and the slurry runs for about 1 hour, ensuring that the several materials can be fully mixed and evenly mixed, so that the product has stable combustion performance; the entire production process is safe and controllable, the process is simplified, the production capacity is matched, and the performance of the produced agent is stable.

Claims

1. A method for producing a gas generating agent for airbags containing nitroguanidine, comprising treating nitroguanidine containing 20% ​​to 25% water, i.e., wet nitroguanidine, to prepare a gas generating agent for airbags, wherein the gas generating agent for airbags comprises a combustible containing nitroguanidine, a water-soluble adhesive, a solvent, an oxidant and auxiliary components, wherein the combustible containing nitroguanidine comprises wet nitroguanidine and guanidine nitrate, and the water-soluble adhesive is a polyvinyl alcohol solution, characterized in that: The production method is implemented according to the following steps: Step 1, measuring the moisture content of wet nitroguanidine and calculating the feeding weight; Step 2, screening strontium nitrate to obtain fine strontium nitrate particles; Step 3, preparing a polyvinyl alcohol solution by mixing deionized water and polyvinyl alcohol; Step 4, adding wet nitroguanidine and fine strontium nitrate according to the calculated feeding weight into a mixing granulator for mixing, adding polyvinyl alcohol solution at the same time, mixing evenly and granulating to obtain mixed particles; Step 5, drying the mixed particles to obtain dry mixed particles, screening the dry mixed particles to obtain fine dry mixed particles; Step 6: feed the fine dry mixed particles into a mixer, and add other components of the airbag gas generating agent except nitroguanidine, polyvinyl alcohol and strontium nitrate into the mixer, mix them evenly and press them into a shape to make airbag gas generating agent tablets.

2. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: Specifically, step 1 includes: using HS153 infrared moisture analyzer to quickly test the moisture content of nitroguanidine; according to the dry weight of nitroguanidine specified, the moisture content of nitroguanidine is measured according to W 湿态称量重量 =W 干态投料重量 / (1-P 湿态硝基胍水分测试结果 ) Calculate the weighed weight of wet nitroguanidine, i.e. the feed weight.

3. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: In the step 2, strontium nitrate is screened by a pneumatic rotary vibrating screen.

4. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: In step 3, the mass ratio of deionized water to polyvinyl alcohol is 2.5-3.75:

1.

5. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: After the mixing is uniform in step 4, granulation is performed using a 10-mesh screen.

6. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: In step 5, a boiling dryer is used to dry the mixed particles. When the boiling dryer is used for drying, the temperature of the mixed particles is greater than or equal to 50° C., the fan frequency of the boiling dryer is 30 Hz, and the mass content of moisture in the obtained dry mixed particles is less than or equal to 0.1%.

7. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: In step 5, the dry mixed particles are screened through a 24-mesh pneumatic rotary vibrating screen.

8. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: The mixer used in step 6 is a trough mixer, and the rotation speed of the trough mixer is 25r / min.

9. The method for producing a gas generating agent for airbags containing nitroguanidine according to claim 1, characterized in that: The tablets in step 6 are pressed and formed by a 22-punch rotary tablet press.

10. A gas generating agent for airbag containing nitroguanidine, characterized in that: The gas generating agent for safety airbags containing nitroguanidine is produced by the production method of any one of claims 1 to 9.

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