Aircraft deicing fluid thickened with super-long-chain polyoxyethylene ether surfactant and method of making

Abstract

The application discloses a super-long chain (carbon atom number in a hydrophobic tail chain is greater than or equal to 18) polyoxyethylene ether surfactant thickened aircraft deicing and anti-icing liquid and a preparation method. The super-long chain polyoxyethylene ether surfactant thickened aircraft deicing and anti-icing liquid comprises the following components and mass percentages: alcohol 40-69%, deionized water 30-59%, and surfactant 0.2-2.0%, wherein the surfactant is a polyoxyethylene monomethyl ether ester of docosanoic acid (C 22 -350) with the following structural formula: The application obtains a deicing and anti-icing liquid which is good in deicing and anti-icing performance and relatively environment-friendly, solves the problems that a polymer-based deicing and anti-icing liquid is easy to be rehydrated to form a hydrated gel on the surface of an aircraft and that a surfactant itself or other additives cause corrosion on the surface of the aircraft under the premise of ensuring the deicing and anti-icing effect.

Description

Technical Field

[0001] This invention belongs to the field of surface de-icing and anti-icing, specifically relating to a type of de-icing and anti-icing fluid and its preparation method. Background Technology

[0002] When aircraft stop or stay overnight at high-altitude airports, ice, frost, or snow can easily accumulate on the leading edges of their wings and tail, around the engine air intakes, and on various probes and antennas. This not only increases the weight of the aircraft but also roughens its surface, alters its smoothness and shape, disrupts the smooth flow of air around the wing surface, and leads to a decrease in the aircraft's lift-to-drag ratio and lift coefficient, difficulty in controlling its flight attitude, and changes in its flight characteristics. It can even cause the aircraft to stall and result in serious flight accidents. Therefore, de-icing is a key aspect of ensuring safe flight.

[0003] Currently, the most effective ground-based de-icing method is the use of non-Newtonian aircraft de-icing fluid. The international aviation industry commonly uses a water-soluble polymer thickener as a rheology modifier added to an alcohol-water mixture to create a shear-thinning non-Newtonian fluid for aircraft de-icing. When sprayed onto the aircraft surface, this fluid not only removes accumulated ice but also inhibits further icing. Most of this sprayed fluid is blown off during takeoff, but small amounts may remain in less visible areas (such as wings and elevators). These residual polymers readily form hydrated gels upon contact with water vapor in the air, potentially jamming the elevators and posing a flight safety hazard.

[0004] Avoiding the use of polymers in aircraft de-icing and anti-icing fluids is an effective solution to the aforementioned problems. Patent application CN112094624A discloses a "surfactant / hydrophobic associating polymer viscoelastic fluid with de-icing and anti-icing functions and its preparation method," yielding a de-icing and anti-icing viscoelastic fluid based on a surfactant and hydrophobic associating polymer compound. Although the amount of polymer used is reduced, the small amount of polymer still may cause hydration and gelation problems caused by the polymer thickener. Patent application CN105199671A discloses a "de-icing fluid thickened by oligopeptidocationic surfactant and its preparation method," yielding a de-icing and anti-icing fluid based on oligopeptidocationic surfactants. However, the surfactant used requires the addition of inorganic or organic salts to obtain a non-Newtonian de-icing and anti-icing fluid. The addition of salt greatly increases the risk of corrosion to the aircraft surface, affecting operational safety. Patent application CN106883819A discloses "An anti-icing fluid based on ultra-long chain viscoelastic surfactant and its preparation method", which yields an aircraft anti-icing fluid with ultra-long chain surfactant thickening. However, the preparation process of the surfactant used is complicated and the concentration used is still high, which increases the cost of the anti-icing fluid. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing an aircraft de-icing and anti-icing fluid thickened with ultra-long chain (hydrophobic tail chain with ≥18 carbon atoms) polyoxyethylene ether surfactant and its preparation method. This results in a de-icing and anti-icing fluid with good performance and is relatively environmentally friendly. While ensuring the de-icing and anti-icing effect, this invention solves the problems of polymer-based de-icing and anti-icing fluids easily rehydrating on aircraft surfaces to form hydrated gels, and the corrosion of aircraft surfaces by surfactants or other additives.

[0006] The aircraft de-icing fluid thickened with an ultra-long-chain polyoxyethylene ether surfactant provided by this invention has the following composition and mass percentage of each component: alcohol 40%–69%, deionized water 30%–59%, and surfactant 0.2%–2.0%, wherein the surfactant is polyoxyethylene monomethyl ether dodecanoate (C... 22 -350), the structural formula is as follows:

[0007]

[0008] In the above technical solution of the present invention, the alcohol is further described as a dialkyl alcohol having 2 to 5 carbon atoms; the dialkyl alcohol is preferably 1,2-propanediol.

[0009] In the above technical solution of the present invention, the preferred composition and mass percentage of the aircraft de-icing fluid thickened by the polyoxyethylene ether surfactant are as follows: alcohol 48% to 49%, deionized water 49% to 51%, and surfactant 0.3% to 2.0%.

[0010] The preparation method of aircraft de-icing fluid thickened with ultra-long chain polyoxyethylene ether surfactant provided by the present invention is as follows:

[0011] The preparation method of the above-mentioned aircraft de-icing and anti-icing fluid thickened with polyoxyethylene ether surfactant provided by the present invention: after mixing deionized water and alcohol and stirring evenly, C is added. 22 -350 surfactant, heat and stir until completely dissolved.

[0012] In the above technical solution of the present invention, the alcohol is further described as a dialkyl alcohol with 2 to 5 carbon atoms, preferably 1,2-propanediol.

[0013] This invention also provides the application of the above-mentioned ultra-long chain polyoxyethylene ether in aircraft de-icing fluid.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The ultra-long chain polyoxyethylene ether surfactant described in this invention is soluble in alcohol / water mixed solvents for thickening, but insoluble in water. It can replace polymers as thickeners in the application of de-icing fluids, thereby solving the problem of residual polymers reabsorbing water to form hydrated gels that jam the elevator, causing safety hazards.

[0016] 2. The polyoxyethylene ether surfactant described in this invention uses an ultra-long carbon chain as a hydrophobic tail chain, which enables the surfactant to have thickening and shear-thinning effects at lower concentrations, thus having a cost advantage.

[0017] 3. The polyoxyethylene ether surfactant described in this invention can form a viscoelastic fluid as a single component, does not contain other organic or inorganic salts, and the surfactant itself does not ionize, thus exhibiting low corrosivity to object surfaces. Attached Figure Description

[0018] Figure 1 It is 0.3 wt.% C in Example 2 22 Viscosity-shear rate relationship at different temperatures in water / 1,2-propanediol at -350°C.

[0019] Figure 2 It is 0.4 wt.% C in Example 3 22 Viscosity-shear rate relationship at different temperatures in water / 1,2-propanediol at -350°C.

[0020] Figure 3 It is 0.5 wt.% C in Example 4 22 Viscosity-shear rate relationship at different temperatures in water / 1,2-propanediol at -350°C.

[0021] Figure 4 It is 1.0 wt.% C in Example 5 22 Viscosity-shear rate relationship at different temperatures in water / 1,2-propanediol at -350°C.

[0022] Figure 5 It is 2.0 wt.% C in Example 6 22 Viscosity-shear rate relationship at different temperatures in water / 1,2-propanediol at -350°C.

[0023] Figure 6 It is 0.5 wt.% C in Example 7 22 Anti-icing effect of de-icing fluid composed of -350 and water / 1,2-propanediol on aluminum alloy substrate.

[0024] Figure 7 The 0.5 wt.% C sample was prepared in accordance with the requirements of "GB / T 20867-2012" in Example 8. 22The results of the compatibility test between the de-icing fluid composed of -350 and water / 1,2-propanediol and the aircraft fuselage materials are shown in the figure. (a) is a comparison photo of the aluminum alloy test piece before and after being fully immersed in the de-icing fluid. (b) and (c) are microscopic morphology photos of the aluminum alloy test piece before and after being immersed in the de-icing fluid.

[0025] Figure 8 It is 0.5 wt.% C in Example 9 22 The change in the permeability of the -350 aqueous solution with temperature in the range of 0 to 90℃. Detailed Implementation

[0026] The following examples further illustrate the aircraft de-icing and anti-icing fluid thickened with the ultra-long-chain polyoxyethylene ether surfactant described in this invention and its preparation method. These examples are only used to more clearly illustrate the technical solution of this invention and should not be construed as limiting the scope of protection of this invention. In the following examples, the surfactant is a laboratory-made C... 22 -350. In the above technical solution of the present invention, the ultra-long chain polyoxyethylene ether surfactant is prepared by the following method:

[0027] (1) 5.00g of a substance with a molecular weight of 350g·mol -1 Polyoxyethylene monomethyl ether (MPEG) was added to 250g of dichloromethane solution and stirred in a 25°C water bath until the compound dissolved.

[0028] (2) Weigh 0.35g of catalyst 4-dimethylaminopyridine and 0.84g of dimethylaminopyridine toluenesulfonate, add them to the above reaction solution, and stir until the catalyst is completely dissolved.

[0029] (3) Then add 5.80g of docosanoic acid C 22 Add FA and stir until dissolved.

[0030] (4) Add 5.88 g of condensing agent N,N'-dicyclohexylcarboimide to the above solution. Continue stirring until homogeneous, and carry out the esterification reaction. The reaction will stop after 48 h.

[0031] (5) After the reaction is complete, the mixture is rotary evaporated and then filtered out using a pinhole filter to remove the condensing agent, thus obtaining the crude product.

[0032] (6) The crude product was separated and purified by column chromatography, and finally dried under vacuum to obtain the surfactant polyoxyethylene monomethyl ether dodecanoate C. 22 -350.

[0033] Example 1

[0034] In this embodiment, the formula of the anti-icing fluid is as follows:

[0035]

[0036] Preparation: Add the prescribed amount of 1,2-propanediol to deionized water at room temperature and mix thoroughly. Then add different amounts of C... 22 -350°C, heat to 50°C and stir until the surfactant is completely dissolved to obtain the anti-icing fluid.

[0037] According to the People's Republic of China Petroleum and Chemical Industry Standard SH / T 0090-91, the freezing points of this de-icing fluid are -37.2℃, -37.0℃, -37.1℃, -36.9℃, and -37.1℃, respectively. This indicates that the de-icing fluid of the present invention has a low freezing point and can be used in most extremely cold environments.

[0038] Example 2

[0039] In this embodiment, the formula of the anti-icing fluid is as follows:

[0040] Components Mass percentage (wt.%) Deionized water 50.78 Alcohol: 1,2-Propanediol 48.92 <![CDATA[Surfactant: C 22 -350]]> 0.30

[0041] Preparation: Add the prescribed amount of 1,2-propanediol to deionized water at room temperature and mix thoroughly. Then add the above-prescribed amount of C... 22 Stir at -350°C and 50°C until completely dissolved to obtain the de-icing fluid.

[0042] The relationship between the apparent viscosity and shear rate of the de-icing fluid was tested using a rotational rheometer (Anto Paar, MCR 302) at temperatures of -20℃, -10℃, 0℃, and 10℃. The results are as follows: Figure 1 As shown. By Figure 1 It can be seen that the de-icing fluid exhibits a high apparent viscosity at low shear rates, and the viscosity decreases significantly with increasing shear rate, demonstrating obvious shear-thinning characteristics, which meets the rheological performance requirements of a non-Newtonian fluid de-icing fluid. Furthermore, the maximum shear viscosity of this de-icing fluid varies with temperature, reaching its maximum at low temperatures, making it suitable for low-temperature environments.

[0043] Example 3

[0044] In this embodiment, the formula of the anti-icing fluid is as follows:

[0045] Components Mass percentage (wt.%) Deionized water 50.73 Alcohol: 1,2-Propanediol 48.87 <![CDATA[Surfactant: C 22 -350]]> 0.40

[0046] Preparation: Add the prescribed amount of 1,2-propanediol to deionized water at room temperature and mix thoroughly. Then add the above-prescribed amount of C... 22 Stir at -350°C and 50°C until completely dissolved to obtain the de-icing fluid.

[0047] The relationship between the apparent viscosity and shear rate of the de-icing fluid was tested using a rotational rheometer (Anto Paar, MCR 302) at temperatures of -20℃, -10℃, 0℃, and 10℃. The results are as follows: Figure 2 As shown. By Figure 2 It can be seen that the de-icing fluid exhibits a high apparent viscosity at low shear rates, and the viscosity decreases significantly with increasing shear rate, demonstrating obvious shear-thinning characteristics, which meets the rheological performance requirements of a non-Newtonian fluid de-icing fluid. Furthermore, the maximum shear viscosity of this de-icing fluid varies with temperature, reaching its maximum at low temperatures, making it suitable for low-temperature environments.

[0048] Example 4

[0049] In this embodiment, the formula of the anti-icing fluid is as follows:

[0050] Components Mass percentage (wt.%) Deionized water 50.68 Alcohol: 1,2-Propanediol 48.82 <![CDATA[Surfactant: C 22 -350]]> 0.50

[0051] Preparation: Add the prescribed amount of 1,2-propanediol to deionized water at room temperature and mix thoroughly. Then add the above-prescribed amount of C... 22 Stir at -350°C and 50°C until completely dissolved to obtain the de-icing fluid.

[0052] The relationship between the apparent viscosity and shear rate of the de-icing fluid was tested using a rotational rheometer (Anto Paar, MCR 302) at temperatures of -20℃, -10℃, 0℃, and 10℃. The results are as follows: Figure 3 As shown. By Figure 3 It can be seen that the de-icing fluid exhibits a high apparent viscosity at low shear rates, and the viscosity decreases significantly with increasing shear rate, demonstrating obvious shear-thinning characteristics, which meets the rheological performance requirements of a non-Newtonian fluid de-icing fluid. Furthermore, the maximum shear viscosity of this de-icing fluid varies with temperature, reaching its maximum at low temperatures, making it suitable for low-temperature environments.

[0053] Example 5

[0054] In this embodiment, the formula of the anti-icing fluid is as follows:

[0055] Components Mass percentage (wt.%) Deionized water 50.43 Alcohol: 1,2-Propanediol 48.57 <![CDATA[Surfactant: C 22 -350]]> 1.00

[0056] Preparation: Add the prescribed amount of 1,2-propanediol to deionized water at room temperature and mix thoroughly. Then add the above-prescribed amount of C... 22 Stir at -350°C and 50°C until completely dissolved to obtain the de-icing fluid.

[0057] The relationship between the apparent viscosity and shear rate of the de-icing fluid was tested using a rotational rheometer (Anto Paar, MCR 302) at temperatures of -20℃, -10℃, 0℃, and 10℃. The results are as follows: Figure 4 As shown. By Figure 4 It can be seen that the de-icing fluid exhibits a high apparent viscosity at low shear rates, and the viscosity decreases significantly with increasing shear rate, demonstrating obvious shear-thinning characteristics, which meets the rheological performance requirements of a non-Newtonian fluid de-icing fluid. Furthermore, the maximum shear viscosity of this de-icing fluid varies with temperature, reaching its maximum at low temperatures, making it suitable for low-temperature environments.

[0058] Example 6

[0059] In this embodiment, the formula of the anti-icing fluid is as follows:

[0060] Components Mass percentage (wt.%) Deionized water 49.92 Alcohol: 1,2-Propanediol 48.08 <![CDATA[Surfactant: C 22 -350]]> 2.00

[0061] Preparation: Add the prescribed amount of 1,2-propanediol to deionized water at room temperature and mix thoroughly. Then add the above-prescribed amount of C... 22 Stir at -350°C and 50°C until completely dissolved to obtain the de-icing fluid.

[0062] The relationship between the apparent viscosity and shear rate of the de-icing fluid was tested using a rotational rheometer (Anto Paar, MCR 302) at temperatures of -20℃, -10℃, 0℃, and 10℃. The results are as follows: Figure 5 As shown. By Figure 5 It can be seen that the de-icing fluid exhibits a high apparent viscosity at low shear rates, and the viscosity decreases significantly with increasing shear rate, demonstrating obvious shear-thinning characteristics, which meets the rheological performance requirements of a non-Newtonian fluid de-icing fluid. Furthermore, the maximum shear viscosity of this de-icing fluid varies with temperature, reaching its maximum at low temperatures, making it suitable for low-temperature environments.

[0063] Example 7

[0064] In this embodiment, the components, content of each component, and preparation method of the anti-icing fluid are the same as in Example 4.

[0065] Immerse the lower half of an aluminum alloy sheet, 2.5cm wide and 7.5cm long, into the aforementioned de-icing liquid, allowing the liquid to adhere to the surface of the lower half of the sheet. Then place the sheet in an environment with a temperature of -20℃ and a relative humidity of 40%.

[0066] After 5 hours, it was found that almost all the parts of the aluminum alloy sheet without anti-icing fluid were frozen, while the parts with anti-icing fluid remained almost unchanged, demonstrating good anti-icing performance. Figure 6 As shown.

[0067] Example 8

[0068] In this embodiment, the components, content of each component, and preparation method of the anti-icing fluid are the same as in Example 4.

[0069] The compatibility test of the de-icing fluid with the fuselage materials was conducted according to "GB / T 20857-2012" issued by the Standardization Administration of China. Three identical aluminum alloy test pieces were immersed in the de-icing fluid for 24 hours, and their appearance changes were observed and their mass changes before and after were tested.

[0070] The results are as follows Figure 7 As shown. Visual inspection of the specimens before and after impregnation, as well as further microscopic observation, revealed no obvious corrosion. The three specimens were weighed before and after impregnation, and the mass reductions were 0.02, 0.14, and 0.14 mg / cm³, respectively. 2 The maximum allowable mass change of the specimen per 24 hours of immersion, as per national standards, is ≤0.3 mg / cm³. 2 The requirements indicate that the system will not corrode the body materials and has good compatibility with the body materials.

[0071] Example 9

[0072] C 22 -350 surfactant 0.03g was placed in 5.97g of deionized water and heated to 90℃ to disperse the surfactant evenly in the water. Then the above solution was placed in a UV-Vis spectrophotometer and cooled from 90℃ to 0℃ at a rate of 1℃ / min. The change in transmittance with temperature was recorded.

[0073] Depend on Figure 8 It is known that surfactants have a permeability close to 0 in the temperature range of 0-90℃, and the solution is white and opaque, indicating that surfactants are insoluble in water. This helps reduce the risk of surfactants recombining with water to form viscoelastic fluids (similar to polymers forming hydrated gels when they come into contact with water).

Claims

1. An aircraft de-icing and anti-icing fluid thickened with an ultra-long-chain polyoxyethylene ether surfactant, characterized in that, Its components and their mass percentages are as follows: alcohol 40%–69%, deionized water 30%–59%, surfactant 0.2%–2.0%, wherein the surfactant is polyoxyethylene monomethyl ether dodecanoate, and its structural formula is as follows: ， The alcohol is 1,2-propanediol.

2. The aircraft de-icing and anti-icing fluid thickened with the ultra-long-chain polyoxyethylene ether surfactant according to claim 1, characterized in that, Its components and the mass percentage of each component are as follows: alcohol 48%~49%, deionized water 49%~51%, surfactant 0.3%~2.0%.

3. The method for preparing the aircraft de-icing and anti-icing fluid thickened with the ultra-long chain polyoxyethylene ether surfactant as described in claim 1 or 2, characterized in that... Includes the following: After mixing and stirring the deionized water and alcohol evenly, add polyoxyethylene monomethyl ether ester docosanoate and surfactant, and heat and stir until completely dissolved.

4. Application of ultra-long chain polyoxyethylene ether in aircraft de-icing fluid, wherein the ultra-long chain polyoxyethylene ether is polyoxyethylene monomethyl ether dodecanoate, and its structural formula is as follows: 。

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