3-mercaptopropyltriethoxysilane modified graphene oxide for reducing adn sensitivity

Abstract

The application discloses application of 3-mercaptopropyl triethoxysilane modified graphene oxide to reduction of ADN sensitivity. The 3-mercaptopropyl triethoxysilane modified graphene oxide is used to reduce the impact sensitivity of ADN and improve the thermal stability and thermal decomposition performance of ADN. Further, the prepared composite can not only reduce the impact sensitivity and friction sensitivity of ADN, but also delay the thermal decomposition temperature of ADN and improve the mass loss.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of energetic materials, and particularly relates to the application of 3-mercaptopropyl triethoxysilane modified graphene oxide for reducing the sensitivity of ADN. BACKGROUND

[0002] ADN (chemical name: ammonium dinitramide) is a new type of high-energy green oxidizer composed of ammonium cation and dinitramide anion, which has the advantages of high density (1.82 g / cm 3 Compared with the common oxidizer ammonium perchlorate (AP), ADN has higher enthalpy of formation (ADN: -1208 kJ / kg, AP: -2782 kJ / kg), smaller average relative molecular mass of combustion gas (ADN: 26, AP: 31), and higher theoretical specific impulse of ADN-based solid propellant than that of AP-based solid propellant by 3 s~10 s. However, its application is limited due to its low sensitivity. SUMMARY

[0003] In view of the defects or deficiencies of the prior art, the present application provides the application of 3-mercaptopropyl triethoxysilane modified graphene oxide for reducing the impact sensitivity and friction sensitivity of ADN or / and improving the thermal stability and mass loss of ADN.

[0004] The present application also provides a preparation method of 3-mercaptopropyl triethoxysilane modified graphene oxide / ADN composite, and the preparation method comprises the following steps:

[0005] Step 1, under the condition of 20~40℃, mix the γ-butyrolactone solution of 3-mercaptopropyl triethoxysilane modified graphene oxide and the γ-butyrolactone solution of ADN uniformly to obtain a mixed solution;

[0006] Step 2, under the condition of 20~40℃, drop the mixed solution obtained in step 1 into an organic solvent; after the dropping is completed, collect the precipitate, dry at room temperature to obtain 3-mercaptopropyl triethoxysilane modified graphene oxide / ADN composite; the organic solvent is selected from one or more than two kinds of mixture of dichloromethane, toluene, cyclohexane and trichloromethane.

[0007] Optionally, graphene oxide is added into γ-butyrolactone, and an ultrasonic dispersion is carried out under the temperature condition of 20~35℃ to obtain a γ-butyrolactone solution of graphene oxide.

[0008] Optionally, ADN is added into γ-butyrolactone, and stirring is carried out uniformly under the temperature condition of 20~35℃ to obtain a γ-butyrolactone solution of ADN.

[0009] Alternatively, the 3-mercaptopropyl triethoxysilane modified graphene oxide gamma-butyrolactone solution is added into the ADN gamma-butyrolactone solution, and after stirring at 20-35℃, the mixed solution obtained in step 1 is prepared by ultrasonic dispersion.

[0010] Alternatively, the use amount ratio of 3-mercaptopropyl triethoxysilane modified graphene oxide and gamma-butyrolactone in the 3-mercaptopropyl triethoxysilane modified graphene oxide gamma-butyrolactone solution is 0.4mg-40mg: 20g-40g; and the use amount ratio of ADN and gamma-butyrolactone in the ADN gamma-butyrolactone solution is 0.3g-2.5g: 10g-50g.

[0011] Alternatively, the use amount of the organic solvent is 500g-1500g.

[0012] The preparation method of the 3-mercaptopropyl triethoxysilane modified graphene oxide / ADN composite of the present application can reduce the impact sensitivity of ADN, improve the thermal stability of ADN, and improve the thermal decomposition performance of the graphene oxide / ADN composite.

[0013] Compared with ADN, the 3-mercaptopropyl triethoxysilane modified graphene oxide / ADN composite of the present application has a spherical structure, and the particles are uniform; the impact sensitivity is reduced from 9.31J to 10.0J-19.3J, and the friction sensitivity is reduced from 72% to 20%-31%; the thermal performance of ADN is also improved, the thermal decomposition temperature of ADN is delayed by 1.56℃-5.06℃, thereby improving the thermal stability of ADN, and thus the stability of the propellant formula can be improved; the mass loss is increased by 1.34%-8.98%, thereby promoting the complete decomposition of ADN, and thus ADN can be more fully combusted in the propellant formula. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is the SEM image of ADN used in the embodiment of the present application.

[0015] Figure 2 is the thermal decomposition DSC image (a) and TG image (b) of ADN used in the embodiment of the present application.

[0016] Figure 3 is the SEM image of the SH-SiGO / ADN composite prepared in Example 1 of the present application.

[0017] Figure 4 is the thermal decomposition DSC image (a) and TG image (b) of the SH-SiGO / ADN composite prepared in Example 1 of the present application.

[0018] Figure 5is an SEM image of a graphene / ADN composite prepared in Inventive Comparative Example 1.

[0019] Figure 6 is a thermal decomposition DSC graph (a) and TG graph (b) of a graphene / ADN composite prepared in Inventive Comparative Example 1.

[0020] Figure 7 is an SEM image of a reduced graphene oxide / ADN composite prepared in Inventive Comparative Example 2.

[0021] Figure 8 is a thermal decomposition DSC graph (a) and TG graph (b) of a reduced graphene oxide / ADN composite prepared in Inventive Comparative Example 2.

[0022] Figure 9 is an SEM image of a carbon nanotube / ADN composite prepared in Inventive Comparative Example 3.

[0023] Figure 10 is a thermal decomposition DSC graph (a) and TG graph (b) of a carbon nanotube / ADN composite prepared in Inventive Comparative Example 3.

[0024] Figure 11 is an SEM image of a composite prepared in Inventive Comparative Example 4.

[0025] Figure 12 is an SEM image of a composite prepared in Inventive Comparative Example 5.

[0026] Figure 13 is an SEM image of a composite prepared in Inventive Comparative Example 6.

[0027] Figure 14 is an SEM image of a composite prepared in Inventive Comparative Example 7. DETAILED DESCRIPTION

[0028] Unless otherwise defined, scientific and technical terms used in this text are understood according to the common knowledge of the relevant field. It should be noted that, on the basis of the preparation scheme of the carrier of the present application, those skilled in the art can make optimal choices for the selection of the reagents involved in the method of the present application, including but not limited to the specific reagents, the ratio of the reagents in each step, the temperature and time, the drying temperature and the calcination temperature, so as to achieve the relevant effects of the carrier of the present application.

[0029] 3-mercaptopropyltriethoxysilane modified graphene oxide used in the following examples was prepared by the method disclosed in CN202010885150.0; graphene, reduced graphene oxide and carbon nanotubes were purchased from the distributor Beijing Bailingwei Technology Co., Ltd.; ammonium dinitramide (ADN) was provided by Xi'an Institute of Modern Chemistry, with an impact sensitivity of 9.3 J, a friction sensitivity (66°, 2.5 MPa) of 72%, a thermal decomposition temperature of 195.07℃, and a mass loss of 83.17% in TG test, Figure 1 and Figure 2 respectively, are the electron micrograph, thermal decomposition DSC graph and TG graph of ADN.

[0030] The impact sensitivity in the following examples was tested by the impact sensitivity test method in GJB770A-97; the friction sensitivity was tested by the friction sensitivity test method in GJB770A-97.

[0031] Example 1:

[0032] 0.4 mg of SH-SiGO was added to 20 g of γ-butyrolactone and ultrasonically dispersed at 21℃ for 1 h; 0.4 g of ADN was added to 14 g of γ-butyrolactone and stirred at 26℃ for 12 min until the ADN was completely dissolved; the SH-SiGO dispersion was poured into the ADN solution, and the system was stirred at 24℃ for 0.7 h and ultrasonically dispersed for 14 min.

[0033] The mixed solution of ADN and SH-SiGO was added dropwise to 540 g of dichloromethane under stirring at 21℃, the solution was filtered after the dropwise addition was completed, and the constant weight was obtained after air drying at room temperature, to obtain 0.38 g of SH-SiGO / ADN composite.

[0034] It was detected that the impact sensitivity of the SH-SiGO / ADN composite prepared in this example was 10.0 J, the friction sensitivity was 20%, the thermal decomposition temperature was 198.14℃, and the mass loss after thermal decomposition was 89.22%.

[0035] Example 2:

[0036] 15 mg of SH-SiGO was added to 55 g of γ-butyrolactone and ultrasonically dispersed at 24℃ for 1.0 h; 1.9 g of ADN was added to 48 g of γ-butyrolactone and stirred at 28℃ for 26 min until the ADN was completely dissolved; the SH-SiGO dispersion was poured into the ADN solution, and the system was stirred at 36℃ for 0.9 h and ultrasonically dispersed for 12 min.

[0037] The mixed solution of ADN and SH-SiGO was added dropwise to 700 g of dichloromethane under stirring at 38℃, the solution was filtered after the dropwise addition was completed, and the constant weight was obtained after air drying at room temperature, to obtain 1.78 g of SH-SiGO / ADN composite.

[0038] The impact sensitivity of the SH-SiGO / ADN composite prepared in this example was 11.7 J, the friction sensitivity was 22%, the thermal decomposition temperature was 196.63°C, and the mass loss after thermal decomposition was 88.16%.

[0039] Example 3:

[0040] Step 1, 4.5 mg of 3-mercapto propyl triethoxysilane modified graphene oxide (SH-SiGO) was added to 40 g of γ-butyrolactone and ultrasonically dispersed at 25°C for 1.5 h; 0.3 g of ADN was added to 10 g of γ-butyrolactone and stirred at 25°C for 15 min until the ADN was completely dissolved; the SH-SiGO dispersion was poured into the ADN solution, and the system was stirred at 30°C for 1 h and ultrasonically dispersed for 10 min;

[0041] Step 2, the mixed solution of ADN and SH-SiGO obtained in step 1 was added dropwise to 500 g of dichloromethane under stirring at 30°C, and the precipitate was collected by filtering the solution after the addition was completed, and dried at room temperature to constant weight, to obtain 0.28 g of SH-SiGO / ADN composite.

[0042] The impact sensitivity of the SH-SiGO / ADN composite prepared in this example was 19.3 J, the friction sensitivity was 31%, the thermal decomposition temperature was 200.13°C, and the mass loss after thermal decomposition was 84.51%, as shown in Figure 4 .

[0043] Scanning electron microscope (SEM) analysis: Figure 1 The ADN solid was needle-like crystals, and the particles were uneven, while the SH-SiGO / ADN composite prepared in this example had a spherical structure and was relatively uniform, as shown in Figure 3 .

[0044] Comparative Example 1:

[0045] The difference between this comparative example and Example 3 was that SH-SiGO was replaced by graphene; the SEM analysis of the prepared composite is shown in Figure 5 .

[0046] The impact sensitivity of the composite prepared in this comparative example was 9.5 J, the friction sensitivity was 72%, the thermal decomposition temperature was 195.75°C, and the mass loss after thermal decomposition was 93.76%, as shown in Figure 6 .

[0047] Comparative Example 2:

[0048] The difference between this comparative example and Example 3 was that SH-SiGO was replaced by reduced graphene oxide; the SEM analysis of the prepared composite is shown in Figure 7as shown in Figure 6. It was detected that the impact sensitivity of the compound prepared in this comparative example was 9.0 J, the friction sensitivity was 68%, the thermal decomposition temperature was 189.28 °C, and the thermal decomposition mass loss was 92.52%, as shown in Figure 7. Figure 8 as shown in Figure 6.

[0049] Comparative Example 3:

[0050] The difference between this comparative example and Example 3 is that SH-SiGO was replaced by carbon nanotubes. The SEM analysis of the prepared compound is shown in Figure 6. Figure 9 as shown in Figure 6.

[0051] It was detected that the impact sensitivity of the compound prepared in this comparative example was 8.0 J, the friction sensitivity was 64%, the thermal decomposition temperature was 194.55 °C, and the thermal decomposition mass loss was 93.69%, as shown in Figure 7. Figure 10 as shown in Figure 6.

[0052] Comparative Example 4:

[0053] The difference between this comparative example and Example 3 is that γ-butyrolactone in it was replaced by butyrolactone. The SEM analysis of the prepared compound is shown in Figure 6. Figure 11 as shown in Figure 6.

[0054] It was detected that the impact sensitivity of the compound prepared in this comparative example was 7.7 J, the friction sensitivity was 54%, the thermal decomposition temperature was 194.99 °C, and the thermal decomposition mass loss was 79.04%.

[0055] Comparative Example 5:

[0056] The difference between this comparative example and Example 3 is that γ-butyrolactone in it was replaced by N-methylpyrrolidone. The SEM analysis of the prepared compound is shown in Figure 6. Figure 12 as shown in Figure 6.

[0057] It was detected that the impact sensitivity of the compound prepared in this comparative example was 6.1 J, the friction sensitivity was 60%, the thermal decomposition temperature was 195.02 °C, and the thermal decomposition mass loss was 79.57%.

[0058] Comparative Example 6:

[0059] The difference between this comparative example and Example 3 is that in Step 1, 4.5 mg of SH-SiGO and ADN 0.3 g were added to 50 g of γ-butyrolactone, and stirred at 25 °C for 1 hour 155 min. The SEM analysis of the prepared compound is shown in Figure 6. Figure 13 as shown in Figure 6.

[0060] It was detected that the impact sensitivity of the compound prepared in this comparative example was 5.5 J, the friction sensitivity was 70%, the thermal decomposition temperature was 193.47 °C, and the thermal decomposition mass loss was 81.17%.

[0061] Comparative Example 7:

[0062] The difference between this comparative example and Example 3 is that dichloromethane in Step 2 is replaced by 1,4-dioxane; the SEM analysis of the prepared composite is as follows Figure 14 ;

[0063] It is detected that the impact sensitivity of the composite prepared in this comparative example is 8.9 J, the friction sensitivity is 72%, the thermal decomposition temperature is 194.88°C, and the mass loss after thermal decomposition is 82.57%.

[0064] Example 4:

[0065] 40 mg of SH-SiGO was added to 40 g of γ-butyrolactone and ultrasonically dispersed at 24°C for 1.4 h; 2.5 g of ADN was added to 45 g of γ-butyrolactone and stirred at 28°C for 25 min until the ADN was completely dissolved; the SH-SiGO dispersion was poured into the ADN solution, and the system was stirred at 35°C for 0.8 h and ultrasonically dispersed for 14 min;

[0066] The mixed solution of ADN and SH-SiGO was added dropwise to 1130 g of dichloromethane under stirring at 34°C, and the solution was filtered after the dropwise addition was completed, and was air-dried at room temperature to constant weight, to obtain 2.36 g of SH-SiGO / ADN composite.

[0067] It is detected that the impact sensitivity of the SH-SiGO / ADN composite prepared in this example is 11.9 J, the friction sensitivity is 26%, the thermal decomposition temperature is 197.84°C, and the mass loss after thermal decomposition is 92.15%.

[0068] The detection results of the products prepared in the above examples and comparative examples are shown in Table 1.

[0069] Table 1

[0070]

Claims

1. Use of 3-mercaptopropyl triethoxysilane modified graphene oxide for reducing impact sensitivity and friction sensitivity of ammonium dinitramide and improving thermal stability and thermal decomposition mass loss of ammonium dinitramide.

2. A method for preparing a 3-mercaptopropyltriethoxysilane modified graphene oxide / diammonium nitro compound, characterized by, The method comprises the following steps: Step 1, under the condition of 20-40℃, mix the γ-butyrolactone solution of 3-mercaptopropyl triethoxysilane modified graphene oxide and the γ-butyrolactone solution of ADN uniformly to obtain a mixed solution; Step 2, under the condition of 20-40℃, drop the mixed solution obtained in step 1 into an organic solvent; after the dropping is completed, collect the precipitate, dry at room temperature to obtain a 3-mercaptopropyl triethoxysilane modified graphene oxide / ammonium dinitramide composite; the organic solvent is selected from one or more than two kinds of mixture of dichloromethane, toluene, cyclohexane and chloroform.

3. The method for preparing 3-mercaptopropyltriethoxysilane modified graphene oxide / diammonium nitrate complex according to claim 2, characterized in that, The graphene oxide is added into γ-butyrolactone, and a γ-butyrolactone solution of graphene oxide is prepared by ultrasonic dispersion under the condition of 20-35℃.

4. The method for preparing 3-mercaptopropyltriethoxysilane modified graphene oxide / diammonium nitroamide composite according to claim 2, characterized in that, The ammonium dinitramide is added into γ-butyrolactone, and a γ-butyrolactone solution of ADN is prepared by stirring uniformly under the condition of 20-35℃.

5. The method of preparing 3-mercaptopropyltriethoxysilane modified graphene oxide / diammonium nitroamide composite according to claim 2, characterized in that, The γ-butyrolactone solution of 3-mercaptopropyl triethoxysilane modified graphene oxide is added into the γ-butyrolactone solution of ADN, and the mixed solution obtained in step 1 is prepared by stirring under the condition of 20-35℃ and then ultrasonic dispersion.

6. The method of preparing 3-mercaptopropyltriethoxysilane modified graphene oxide / diammonium nitroamide composite according to claim 2, characterized in that, The amount ratio of 3-mercaptopropyl triethoxysilane modified graphene oxide and γ-butyrolactone in the γ-butyrolactone solution of 3-mercaptopropyl triethoxysilane modified graphene oxide is 0.4mg-40mg:20g-40g; the amount ratio of ADN and γ-butyrolactone in the γ-butyrolactone solution of ADN is 0.3g-2.5g:10g-50g.

7. The method for preparing the 3-mercaptopropyltriethoxysilane-modified graphene oxide / dinitroamide ammonium composite according to claim 6, characterized in that, The amount of the organic solvent is 500g-1500g.

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