A method for improving the migration resistance of propellant liners

Abstract

The application discloses a method for improving the anti-migration performance of propellant lining and belongs to the field of composite material preparation. Graphene oxide is used as nano filler and octadecylamine is used as modifier to realize the chemical grafting of amide groups on the surface of graphene oxide and the elimination of polar groups in anhydrous ethanol solution. The amide groups are grafted on the surface of graphene oxide, the polar groups on the surface of graphene oxide are reduced, the graphene oxide filler is better dispersed in the matrix material, and the electronegativity of the surface of graphene oxide is promoted to form electrostatic repulsion with the easily-migrated plasticizer, so that the anti-migration performance of the propellant lining is improved. The preparation process is simple, and the modification process of graphene oxide is controllable.

Description

Technical Field

[0001] This invention belongs to the field of composite material preparation, and specifically relates to a method for using modified graphene oxide to improve the anti-migration properties of propellant liners. Background Technology

[0002] During long-term storage, external factors such as temperature, humidity, and light can cause the migration of small molecules in propellants, including nitroglycerin and energetic plasticizers. The continuous migration of plasticizers from the propellant grain directly leads to grain shrinkage, coating swelling, and disruption of the interfacial bond between the propellant and coating. This significantly reduces interfacial adhesion strength, making debonding more likely and potentially causing accidents. Therefore, we need a material that can both tightly bond the propellant and coating and possess excellent anti-migration properties. Propellant liners were developed to meet this need. However, with the continuous development of high-energy solid propellants, the performance requirements for liners are constantly increasing, and modifications to liner materials are being proposed. Adding nanofillers has become a mainstream approach in many studies.

[0003] The high aspect ratio and high electron cloud density of graphene oxide (GO) carbon rings enable it to impede the penetration of atoms and molecules, thus making it a promising nanomaterial for barrier applications. The numerous oxygen-containing groups on the GO surface provide more active sites for material modification and preparation. Recent studies have shown that GO exhibits excellent barrier effects in polymer composites. For example, Zheng et al. (Zheng L, Jerrams S, Xu Z, et al. Enhanced gas barrier properties of graphene oxide / rubber composites with strong interfaces constructed by graphene oxide and sulfur[J]. Chemical Engineering Journal,2020, 383:599-608.) constructed a robust interface and filler network by introducing GO into styrene-butadiene rubber (SBR). The composite filler network and strong interfacial interactions significantly reduced the free volume between SBR molecules, prolonging the molecular path and diffusion time in the matrix, thereby achieving high barrier performance. However, by modifying GO, both the composite crosslinking network of the liner and the dispersibility of GO in the matrix can be improved, thus exhibiting good resistance to small molecule migration. Summary of the Invention

[0004] The purpose of this invention is to provide a method for improving the anti-migration performance of propellant liners. This method involves modifying GO in anhydrous ethanol solution, reducing its surface polar groups and grafting amide groups, allowing the modified GO to be better dispersed in the matrix. Simultaneously, it imparts electronegativity to the GO surface, creating a repulsive effect with plasticizer molecules, thereby improving the anti-migration performance of the propellant liner. This preparation method is simple, the GO modification process is controllable, and it is an effective way to improve the anti-migration performance of propellant liners.

[0005] This invention is achieved using the following technical solution:

[0006] A method for improving the anti-migration performance of propellant liners specifically includes the following steps:

[0007] Step 1: Prepare graphene oxide (GO) using the modified Hummers method.

[0008] Step 2: Place the dried GO and octadecylamine (ODA) obtained in Step 1 into anhydrous ethanol solution and ultrasonically disperse for 2-3 hours. Mix the anhydrous ethanol suspension of GO and the anhydrous ethanol solution of octadecylamine, and graft modify at 75-85℃ for 4-6 hours. Wash with ethanol and deionized water and dry to obtain modified GO.

[0009] Step 3: Prepare an organic solvent dispersion of modified GO, place it in a hydroxyl-terminated polybutadiene (HTPB) matrix and stir until homogeneous. Then keep it warm to remove the organic solvent. Add plasticizer, toluene diisocyanate and catalyst dropwise and react for 2-3 hours. Add triethanolamine (TEA) and stir until homogeneous. Pour the mixture into a mold and vacuum solidify to obtain the propellant liner.

[0010] Preferably, in step two, the concentration of the anhydrous ethanol suspension of GO is 1 mg / mL, the concentration of the anhydrous ethanol solution of ODA is 10 mg / mL, and the mass ratio of GO to ODA is 5:6.

[0011] Preferably, in step three, the HTPB matrix is ​​dehydrated in a vacuum drying oven at 100°C for 1-3 hours.

[0012] Preferably, in step three, the concentration of the organic solvent dispersion of modified GO is 1 mg / mL, which is obtained by ultrasonically dispersing the modified GO in acetone for 1-2 hours.

[0013] Preferably, in step three, the plasticizer is dioctyl sebacate (DOS), and the catalyst is dibutyltin dilaurate (DBTL); the mass ratio of DOS to HTPB is 1:20, the mass ratio of HTPB to DBTL is 1:0.001, and the mass ratio of TEA to HTPB is 0.03:1; toluene diisocyanate is added dropwise according to the curing coefficient R=1.3, and the reaction is carried out under a nitrogen atmosphere for 2-3 hours; after adding TEA and stirring for 1-3 minutes, it is poured into a mold for vacuum curing, and vacuum curing is carried out for 48 hours.

[0014] Compared with the prior art, the advantages of the present invention are:

[0015] (1) This invention reduces the surface polarity by chemically grafting amide groups onto the surface of GO and reducing the polar groups on its surface, making the surface electronegative. The mutual repulsion between charges inhibits the plasticizer, thereby effectively improving the anti-migration performance of the propellant liner. (2) When the concentration of the modified GO dispersion solution is 1 mg / mL, the modified GO can be uniformly dispersed in the organic reagent. Adding it to the matrix material can help its dispersion in the matrix and impart electronegative groups, thus functionally inhibiting the migration of plasticizers. At this time, the migration equilibrium concentration of the propellant liner reaches 56.17%, which is 27.15% higher than the 77.11% of the sample without GO filler and 5.05% higher than the 59.16% of the sample without modified GO filler, both showing significant improvement. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the characterization of GO prepared in Example 1 and Comparative Example 1 of the present invention.

[0017] Figure 2 The images shown are scanning electron microscope (SEM) images of GO prepared in Example 1 and Comparative Example 1 of this invention.

[0018] Figure 3 The above are XPS spectra of GO prepared in Example 1 and Comparative Example 1 of this invention.

[0019] Figure 4 The graphs show the anti-migration properties of the propellant liner prepared in Examples 1-3 and Comparative Example 2 of this invention.

[0020] Figure 5 The graphs show the anti-migration properties of the propellant liner prepared in Example 2 and Comparative Examples 1-2 of this invention.

[0021] Figure 6 This is a bar chart showing the adhesive strength of the propellant liner prepared in Examples 1-3 and Comparative Examples 1-2 of the present invention.

[0022] Figure 7 These are transmission electron microscope (TEM) morphology comparison images of GA prepared in Example 1 and Comparative Example 3 of the present invention. Detailed Implementation

[0023] The technical solution of the present invention will be further described below with reference to examples and accompanying drawings, but the present invention is not limited to these examples.

[0024] The method for improving the anti-migration performance of propellant liners according to the present invention specifically includes the following steps:

[0025] Step 1: Add graphite powder and NaNO3 to H2SO4 solution, then add KMnO4 in batches. Oxidize at a low temperature of 0-10℃ for 1-2 hours, then raise the temperature and react for 3-4 hours. Dilute with deionized water and add a small amount of 30% H2O2 dropwise until the solution turns bright yellow. Wash and dry with dilute hydrochloric acid and deionized water. Specifically: Add graphite powder and NaNO3 to H2SO4 solution at a ratio of 2:1, then add KMnO4 in batches at a ratio of graphite powder:KMnO4 = 1:3, controlling the reaction temperature at 0-10℃. After the KMnO4 addition is complete, raise the temperature to 35℃ and maintain the reaction for 1.5-2.5 hours. Add deionized water and continue the oxidation reaction for 1.5-2.5 hours. Raise the temperature to 90-95℃, add a large amount of deionized water for dilution, cool and add a small amount of 30% H2O2 dropwise until the solution turns bright yellow. Centrifuge the obtained product, wash with dilute hydrochloric acid and deionized water, and dry.

[0026] Step 2: Pour anhydrous ethanol into two beakers, and add the dried GO and ODA from Step 1 to the two beakers of anhydrous ethanol respectively. Sonicate the two beakers for 2-3 hours to obtain anhydrous ethanol suspension of GO and anhydrous ethanol solution of ODA. After sonication, pour the two into a reaction flask one after the other, and perform graft modification at 75-85℃ for 4-6 hours. Wash and dry with ethanol and deionized water.

[0027] Step 3: Disperse the dried modified GO from Step 2 in an organic reagent, pour it into a hydroxyl-terminated polybutadiene (HTPB) matrix and stir. Add plasticizer, toluene diisocyanate and catalyst dropwise and react in a nitrogen atmosphere for 2-3 hours. Add triethanolamine, stir evenly, and then pour it into a mold for vacuum curing.

[0028] Example 1

[0029] Step 1: Pour 50 mL of 98% concentrated H₂SO₄ into a beaker. Weigh 2 g of graphite powder and 1 g of NaNO₃, and add them to the beaker, stirring. Weigh 6 g of KMnO₄ and add it to the flask in 6 portions, 20 min apart, controlling the reaction temperature at 0–10 °C. Raise the temperature to 35 °C and oxidize for 2 h. Add 100 mL of deionized water and maintain the temperature for another 2 h. Raise the temperature to 90 °C, add 200 mL of deionized water to dilute, and cool the solution by adding a small amount of 30% H₂O₂ until the solution turns bright yellow. Centrifuge to obtain the product, wash away the metal ions with dilute hydrochloric acid, wash with water until neutral, and dry. Label the product as graphene oxide.

[0030] Step 2: Weigh 0.25g of GO to prepare a 1mg / mL GO anhydrous ethanol suspension, sonicate for 3 hours, heat to 80℃, sonicate 0.3g of ODA in 30mL of anhydrous ethanol solution, slowly add this to the GO anhydrous ethanol suspension, and react at 80℃ for 15 hours. Wash away unreacted octadecylamine with ethanol and deionized water, dry, and label as GA.

[0031] Step 3: Weigh 39.49g of HTPB into a four-necked flask and place it in a vacuum drying oven at 100℃ for 3 hours to remove water. Weigh 0.03949g of modified GO to prepare a 1mg / mL acetone dispersion and sonicate for 1 hour. Pour the dispersion into a four-necked flask, stir until homogeneous, and keep warm to remove the solvent. Weigh 1.9745g of dioctyl sebacate and 2.1365g of toluene diisocyanate and add them dropwise to the reaction system. Add 1 drop of dibutyltin dilaurate catalyst and react under a nitrogen atmosphere for 3 hours. Weigh 1.1561g of triethanolamine and add it dropwise to the reaction system. Stir until homogeneous and then stop the reaction.

[0032] Step four: The resulting slurry is poured into a mold and vacuum-cured in a vacuum drying oven for 48 hours to obtain the propellant liner. To test the anti-migration performance of the propellant liner, the cured liner is cut into 20×20×2mm pieces and immersed in a plasticizer solution to test its anti-migration performance, labeled as ODA-GO / HTPB. 0.1 .

[0033] Step 5, in order to test the propellant liner ODA-GO / HTPB 0.1 To test the bonding performance, two titanium alloy plates (100×25×1.5mm) were cleaned with anhydrous ethanol. The lining slurry obtained in step three was applied to the titanium alloy plate joint at a size of 25×12.5mm, clamped with dovetail clips, and placed in a vacuum drying oven. The plates were kept at 60℃ for 48 hours. The dovetail clips were then removed to obtain the bonding tensile test sample 1.

[0034] Example 2

[0035] Step 1: Pour 50 mL of 98% concentrated H₂SO₄ into a beaker. Weigh 2 g of graphite powder and 1 g of NaNO₃, and add them to the beaker, stirring. Weigh 6 g of KMnO₄ and add it to the flask in 6 portions, 20 min apart, controlling the reaction temperature at 0–10 °C. Raise the temperature to 35 °C and oxidize for 2 h. Add 100 mL of deionized water and maintain the temperature for another 2 h. Raise the temperature to 90 °C, add 200 mL of deionized water to dilute, and cool the solution by adding a small amount of 30% H₂O₂ until the solution turns bright yellow. Centrifuge to obtain the product, wash away the metal ions with dilute hydrochloric acid, wash with water until neutral, and dry. Label the product as graphene oxide.

[0036] Step 2: Weigh 0.25g of GO to prepare a 1mg / mL anhydrous ethanol suspension, sonicate for 3 hours, heat to 80℃, sonicate 0.3g of ODA in the ethanol solution, slowly add it to the GO suspension, and react at 80℃ for 15 hours. Wash away unreacted octadecylamine with ethanol and deionized water, dry, and label as GA.

[0037] Step 3: Weigh 38.95g of HTPB into a four-necked flask and place it in a vacuum drying oven at 100℃ for 3 hours to remove water. Weigh 0.0584g of modified GO to prepare an organic dispersion of 1mg / mL and sonicate for 1 hour. Pour the dispersion into a four-necked flask, stir until homogeneous, and keep warm to remove the solvent. Weigh 1.9475g of dioctyl sebacate and 2.1073g of toluene diisocyanate and add them dropwise to the reaction system. Add 1 drop of dibutyltin dilaurate and react under a nitrogen atmosphere for 3 hours. Weigh 1.1403g of triethanolamine and add it dropwise to the reaction system. Stir until homogeneous and then stop the reaction.

[0038] Step four: The resulting slurry is poured into a mold and vacuum-cured in a vacuum drying oven for 48 hours to obtain the propellant liner. To test the anti-migration performance of the propellant liner, the cured liner is cut into 20×20×2mm pieces and immersed in a plasticizer solution to test its anti-migration performance, labeled as ODA-GO / HTPB. 0.2 .

[0039] Step 5, in order to test the propellant liner ODA-GO / HTPB 0.2 To test the bonding performance, two titanium alloy plates (100×25×1.5mm) were cleaned with anhydrous ethanol. The lining slurry obtained in step three was applied to the titanium alloy plate joint at a size of 25×12.5mm, clamped with dovetail clips, and placed in a vacuum drying oven. The plates were kept at 60℃ for 48 hours. The dovetail clips were then removed to obtain the bonding tensile test sample 2.

[0040] Example 3

[0041] Step 1: Pour 50 mL of 98% concentrated H₂SO₄ into a beaker. Weigh 2 g of graphite powder and 1 g of NaNO₃, and add them to the beaker, stirring. Weigh 6 g of KMnO₄ and add it to the flask in 6 portions, 20 min apart, controlling the reaction temperature at 0–10 °C. Raise the temperature to 35 °C and oxidize for 2 h. Add 100 mL of deionized water and maintain the temperature for another 2 h. Raise the temperature to 90 °C, add 200 mL of deionized water to dilute, and cool the solution by adding a small amount of 30% H₂O₂ until the solution turns bright yellow. Centrifuge to obtain the product, wash away the metal ions with dilute hydrochloric acid, wash with water until neutral, and dry. Label the product as graphene oxide.

[0042] Step 2: Weigh 0.25g of GO to prepare a 1mg / mL anhydrous ethanol suspension, sonicate for 3 hours, heat to 80℃, sonicate 0.3g of ODA in the ethanol solution, slowly add it to the GO suspension, and react at 80℃ for 15 hours. Wash away unreacted octadecylamine with ethanol and deionized water, dry, and label as GA.

[0043] Step 3: Weigh 29.97g of HTPB into a four-necked flask and place it in a vacuum drying oven at 100℃ for 3 hours to remove water. Weigh 0.5994g of modified GO to prepare an organic dispersion of 1mg / mL and sonicate for 1 hour. Pour the dispersion into a four-necked flask, stir until homogeneous, and keep warm to remove the solvent. Weigh 1.4985g of dioctyl sebacate and 1.6215g of toluene diisocyanate and add them dropwise to the reaction system. Add 1 drop of dibutyltin dilaurate and react under a nitrogen atmosphere for 3 hours. Weigh 0.8774g of triethanolamine and add it dropwise to the reaction system. Stir until homogeneous and then stop the reaction.

[0044] Step four: The resulting slurry is poured into a mold and vacuum-cured in a vacuum drying oven for 48 hours to obtain the propellant liner. To test the anti-migration performance of the propellant liner, the cured liner is cut into 20×20×2mm pieces and immersed in a plasticizer solution to test its anti-migration performance, labeled as ODA-GO / HTPB. 0.3 .

[0045] Step 5, in order to test the propellant liner ODA-GO / HTPB 0.3 To test the bonding performance, two titanium alloy plates (100×25×1.5mm) were cleaned with anhydrous ethanol. The lining slurry obtained in step three was applied to the titanium alloy plate joint at a size of 25×12.5mm, clamped with dovetail clips, and placed in a vacuum drying oven. The plates were kept at 60℃ for 48 hours. The dovetail clips were then removed to obtain the bonding tensile test sample 3.

[0046] Comparative Example 1

[0047] Step 1: Pour 50 mL of 98% concentrated H₂SO₄ into a beaker. Weigh 2 g of graphite powder and 1 g of NaNO₃, and add them to the beaker, stirring. Weigh 6 g of KMnO₄ and add it to the flask in 6 portions, 20 min apart, controlling the reaction temperature at 0–10 °C. Raise the temperature to 35 °C and oxidize for 2 h. Add 100 mL of deionized water and maintain the temperature for another 2 h. Raise the temperature to 90 °C, add 200 mL of deionized water to dilute, and cool the solution by adding a small amount of 30% H₂O₂ until the solution turns bright yellow. Centrifuge to obtain the product, wash away the metal ions with dilute hydrochloric acid, wash with water until neutral, and dry. Label the product as graphene oxide.

[0048] Step 2: Weigh 31.11g of HTPB into a four-necked flask and place it in a vacuum drying oven at 100℃ for 3 hours to remove water. Weigh 0.0933g of GO to prepare a 2mg / mL organic dispersion and sonicate it for 1 hour. Pour the dispersion into the four-necked flask, stir well, and keep it at a constant temperature to remove the solvent. Weigh 1.5555g of dioctyl sebacate and 1.6831g of toluene diisocyanate and add them dropwise to the reaction system. Add 1 drop of dibutyltin dilaurate and react under a nitrogen atmosphere for 3 hours. Weigh 0.9333g of triethanolamine and add it dropwise to the reaction system. Stir well and then stop the reaction.

[0049] Step 3: The resulting slurry is poured into a mold and vacuum-cured in a vacuum drying oven for 48 hours to obtain the propellant liner. To test the anti-migration performance of the propellant liner, the cured liner is cut into 20×20×2mm pieces and immersed in a plasticizer solution to test its anti-migration performance, labeled as GO / HTPB. 0.3 .

[0050] Step four, in order to test the propellant liner GO / HTPB 0.3 To test the bonding performance, two titanium alloy plates (100×25×1.5mm) were cleaned with anhydrous ethanol. The lining slurry obtained in step two was applied to the joint of the titanium alloy plate at a size of 25×12.5mm. The plates were clamped with dovetail clips and placed in a vacuum drying oven. The plates were kept at 60℃ for 48 hours. The dovetail clips were then removed to obtain the bonding tensile test sample 4.

[0051] Comparative Example 2

[0052] Step 1: Weigh 25.40g of HTPB into a four-necked flask and place it in a vacuum drying oven at 100℃ for 3 hours to remove water. Weigh 1.2700g of dioctyl sebacate and 1.3742g of toluene diisocyanate and add them dropwise to the reaction system. Add 1 drop of dibutyltin dilaurate and react under a nitrogen atmosphere for 3 hours. Weigh 0.7620g of triethanolamine and add it dropwise to the reaction system. Stir until homogeneous and then stop the reaction.

[0053] Step two: The resulting slurry is poured into a mold and placed in a vacuum drying oven for vacuum curing for 48 hours to obtain the propellant liner. To test the anti-migration performance of the propellant liner, the cured liner is cut into small pieces of 20×20×2mm and immersed in a plasticizer solution to test its anti-migration performance, labeled as GO / HTPB0.

[0054] Step 3: To test the bonding performance of the propellant liner GO / HTPB0, two titanium alloy plates (100×25×1.5mm) were cleaned with anhydrous ethanol. The liner slurry obtained in Step 2 was applied to the 25×12.5mm joint of the titanium alloy plate, clamped with dovetail clips, and placed in a vacuum drying oven. The oven was kept at 60℃ for 48 hours. The dovetail clips were then removed to obtain the bonding tensile test sample 5.

[0055] Comparative Example 3

[0056] Step 1: Pour 50 mL of 98% concentrated H₂SO₄ into a beaker. Weigh 2 g of graphite powder and 1 g of NaNO₃, and add them to the beaker, stirring. Weigh 6 g of KMnO₄ and add it to the flask in 6 portions, 20 min apart, controlling the reaction temperature at 0–10 °C. Raise the temperature to 35 °C and oxidize for 2 h. Add 100 mL of deionized water and maintain the temperature for another 2 h. Raise the temperature to 90 °C, add 200 mL of deionized water to dilute, and cool the solution by adding a small amount of 30% H₂O₂ until the solution turns bright yellow. Centrifuge to obtain the product, wash away the metal ions with dilute hydrochloric acid, wash with water until neutral, and dry. Label the product as graphene oxide.

[0057] Step 2: Weigh 0.25g of GO to prepare a 1mg / mL anhydrous ethanol suspension, sonicate for 3 hours, heat to 80℃, sonicate 0.5g of ODA in the ethanol solution, slowly add it to the GO suspension, and react at 80℃ for 15 hours. Wash away unreacted octadecylamine with ethanol and deionized water, dry, and label as GA.

[0058] Figure 1 The images show the infrared spectroscopy comparison of Example 1 and Comparative Example 1 of this invention, namely, octadecylamine-modified graphene oxide, octadecylamine, and untreated graphene oxide. As can be seen from the images, the intensity of the -OH stretching vibration peak of bound water molecules in GO is significantly weakened, indicating that a large number of hydroxyl groups have been reacted and removed. Meanwhile, a new peak at 1547 cm⁻¹ appears in the GA spectrum. -1 The presence of the characteristic CN absorption peak at this location preliminarily indicates that ODA has been successfully grafted onto the GO surface. The curves of ODA and GA show that at 2919 cm⁻¹ in the GA spectrum... -1 and 2849cm -1 A stretching vibration peak of -CH in the -CH2- of the ODA alkyl chain was detected. This further confirms that ODA has been successfully grafted onto the GO surface.

[0059] Figure 2 Examples 1 and 1 (Comparative Example) of this invention show a comparison of the scanning electron microscope (SEM) morphologies of octadecylamine-modified graphene oxide (GA) and untreated graphene oxide. The images show that the unmodified graphene oxide exhibits slight wrinkles and a distinct sheet-like structure. After grafting with ODA, GA shows a significant reduction in oxygen-containing functional groups, resulting in a slightly improved surface smoothness compared to GO. Furthermore, the modified GA sheets are larger than those of the GO sheet structure.

[0060] Figure 3 Examples 1 and Comparative Example 1 of this invention show the XPS spectra of octadecylamine-modified graphene oxide and untreated graphene oxide. The untreated graphene oxide has a relative C content of 66.0 and a relative O content of 34.0. After grafting modification, the relative C content of the modified graphene oxide increased to 93.9 and the relative O content decreased to 4.4. The appearance of N indicates that octadecylamine successfully modified the graphene oxide. After grafting amide groups, the relative C content increased, the relative O content decreased, and the relative N content was 1.7, which indicates that the amide groups were successfully grafted onto the surface of the graphene oxide.

[0061] Figure 4 , 5 The graphs show the anti-migration properties of the propellant liners prepared in Examples 1-3 and Comparative Examples 1-2 of this invention. Comparing Examples 1, 2, and 3 with Comparative Examples 1 and 2, it can be concluded that an appropriate amount of modified graphene oxide can achieve better anti-migration properties of the plasticizer; from Comparative Examples 1 and 2, it can be concluded that octadecylamine-grafted graphene oxide has a significant impact on the anti-migration properties of the propellant liner.

[0062] Figure 6 This is a bar chart showing the adhesive strength of the propellant liner prepared in Examples 1-3 and Comparative Examples 1-2 of this invention. Comparing Examples 1, 2, and 3 with Comparative Examples 1 and 2 in the chart, it can be concluded that an appropriate amount of modified graphene oxide can achieve better adhesive strength.

[0063] Figure 7 These are transmission electron microscopy (TEM) images comparing the morphologies of GA prepared in Example 1 and Comparative Example 3 of this invention. By comparing the morphologies of the examples and comparative examples in the images, a suitable GO to ODA modification mass ratio can be determined.

[0064] In summary, this invention proposes a method to improve the anti-migration performance of propellant liners. It primarily utilizes the fact that octadecylamine-grafted graphene oxide reduces the polar groups on its surface, imparting electronegativity to these groups and promoting electrostatic repulsion between the graphene oxide and plasticizer molecules. This enhances the anti-migration performance of the propellant liner. The preparation process of this invention is simple, the modification direction of the graphene oxide is controllable, and it meets the requirements for effectively improving the anti-migration performance of composite liners. The experimental operation of this invention is simple and quick, the reagents used are economical, the operation process is controllable, and it can significantly improve the interfacial adhesion performance of the propellant liner.

Claims

1. A method for improving the anti-migration performance of propellant liners, characterized in that, Specifically, the steps include the following: Step 1: Graphene oxide is prepared using the modified Hummers method; Step 2: Place the dried graphene oxide and octadecylamine obtained in Step 1 into anhydrous ethanol solution and ultrasonically disperse for 2-3 hours. Mix the anhydrous ethanol suspension of the obtained graphene oxide and the anhydrous ethanol solution of the obtained octadecylamine, and graft modify at 75-85℃ for 4-6 hours. Wash and dry with ethanol and deionized water to obtain modified graphene oxide. Step 3: Prepare an organic solvent dispersion of modified graphene oxide, place it in a hydroxyl-terminated polybutadiene matrix and stir evenly, then keep it warm to remove the organic solvent. Add plasticizer, toluene diisocyanate and catalyst dropwise and react for 2-3 hours. Add triethanolamine and stir evenly, then pour it into a mold and vacuum solidify to obtain the propellant liner.

2. The method as described in claim 1, characterized in that, In step two, the concentration of the anhydrous ethanol suspension of graphene oxide is 1 mg / mL, the concentration of the anhydrous ethanol solution of octadecylamine is 10 mg / mL, and the mass ratio of graphene oxide to octadecylamine is 5:

6.

3. The method as described in claim 1, characterized in that, In step three, the hydroxyl-terminated polybutadiene matrix is ​​dehydrated in a vacuum drying oven at 100°C for 1-3 hours.

4. The method as described in claim 1, characterized in that, In step three, the concentration of the organic solvent dispersion of modified graphene oxide is 1 mg / mL, which is obtained by ultrasonically dispersing the modified graphene oxide in acetone for 1-2 hours.

5. The method as described in claim 1, characterized in that, In step three, the plasticizer is dioctyl sebacate and the catalyst is dibutyltin dilaurate.

6. The method as described in claim 5, characterized in that, The mass ratio of dioctyl sebacate to dibutyltin dilaurate is 1:20, and the mass ratio of hydroxyl-terminated polybutadiene to dibutyltin dilaurate is 1:0.

001.

7. The method as described in claim 1, characterized in that, The mass ratio of triethanolamine to hydroxyl-terminated polybutadiene is 0.03:

1.

8. The method as described in claim 1, characterized in that, In step three, toluene diisocyanate is added dropwise according to the curing coefficient R=1.3, and the reaction is carried out under a nitrogen atmosphere for 2~3 hours.

9. The method as described in claim 1, characterized in that, In step three, triethanolamine is added and stirred for 1-3 minutes, then poured into a mold and vacuum cured for 48 hours.

Images