A dewaxing transparent preparation, its preparation method and application in paraffin section

Abstract

The application discloses a dewaxing transparent preparation and a preparation method and application thereof in paraffin sectioning, and relates to the technical field of preparations for paraffin sectioning. The dewaxing transparent preparation comprises the following raw materials in parts by weight: isooctadecanol 8-12 parts, n-nonane 10-15 parts, n-octane 6-10 parts, white oil 15-25 parts, castor oil 2-5 parts, a surfactant 1-3 parts, and an anti-aging agent 0.1-0.3 parts. The dewaxing transparent preparation prepared by the application has a faster wax dissolving rate, a higher saturated wax dissolving amount and excellent anti-aging performance.

Description

Technical Field

[0001] This invention relates to the field of formulation technology for paraffin tablets, specifically to a dewaxed transparent formulation, its preparation method, and its application in paraffin tablets. Background Technology

[0002] Paraffin sectioning is one of the most commonly used sample preparation methods in pathology, histology, and biomedical research. It involves paraffin embedding, sectioning, dewaxing, staining, and clearing to allow for the observation and analysis of fine tissue structures. Dewaxing and clearing are crucial steps in paraffin section preparation, directly affecting tissue transparency, staining uniformity, and long-term preservation stability. Currently, dewaxing and clearing of paraffin sections typically use xylene, toluene, or other aromatic hydrocarbon organic solvents. While these solvents have strong dissolving power for paraffin, they generally suffer from high toxicity, strong irritation, high volatility, and poor operational safety. Long-term use can adversely affect the health of laboratory personnel and the laboratory environment. Furthermore, single organic solvent systems often rely on the solvent's own dissolving power during dewaxing, resulting in a limited wax dissolution rate and low saturated dewaxing efficiency. In cases of high paraffin residue or dense tissue, incomplete dewaxing and insufficient tissue transparency can easily occur. To reduce toxicity and improve safety, some studies in recent years have attempted to replace traditional aromatic hydrocarbon solvents with isoparaffins, white oils, or vegetable oils. However, these solvent systems generally suffer from low molecular polarity and insufficient penetration and dissolution kinetics for paraffin. When used alone, they result in long dewaxing times, and repeated use can easily lead to paraffin saturation, causing a decrease in dewaxing efficiency and affecting section quality and processing stability. Furthermore, existing dewaxing and clearing preparations are mostly physical dissolution systems, with insufficient attention paid to solvent aging during use and storage. In practical applications, dewaxing and clearing preparations are prone to oxidation under repeated heating, prolonged exposure to air or light, leading to a decline in solvent performance and even causing darkening, fading, or background darkening after tissue staining, which is detrimental to long-term preservation and repeated observation of sections.

[0003] Chinese invention patent CN106370491A discloses an environmentally friendly transparent dewaxing solution, its preparation method, and its application in pathological section preparation. The environmentally friendly transparent dewaxing solution is made from the following raw materials in the indicated mass ratios: 20-60% white oil, 12-45% nonane, 6-35% octane, 5-20% heptane, 4-25% castor oil, 3-18% pentanol, and 2-9% hexanol. The dewaxing solution disclosed in this invention has a simple and reasonable formula, and can serve as both a clearing agent and a dewaxing agent in pathological section preparation, allowing the pathological sectioning process to completely eliminate the need for xylene reagents. However, its anti-aging properties are still insufficient.

[0004] Therefore, it is of great significance to develop a transparent dewaxing formulation that is highly safe, has a fast wax dissolution rate, strong saturated dewaxing ability, and good anti-aging properties. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a dewaxed transparent formulation, its preparation method, and its application in paraffin tableting.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A dewaxed transparent formulation comprising the following raw materials in parts by weight: 8-12 parts of isomeric octadecanol, 10-15 parts of n-nonane, 6-10 parts of n-octane, 15-25 parts of white oil, 2-5 parts of castor oil, 1-3 parts of surfactant, and 0.1-0.3 parts of anti-aging agent; The anti-aging agent is prepared by the following method: S1: (Z,Z)-3,3-thiodipropionate di(9-octadecenyl) ester reacts with 5-amino-1-mercaptopentane under the action of a photoinitiator to generate intermediate 1. The reaction equation is shown below: S2: Intermediate 1 reacts with 6-chloro-N-hydroxyhexanoamide to generate an anti-aging agent. The reaction equation is shown below:

[0007] In step S1, the molar ratio of (Z,Z)-3,3-thiodipropionate di(9-octadecenyl) ester to 5-amino-1-mercaptopentane is 1:(2.02-2.05).

[0008] In step S2, the molar ratio of intermediate 1 to 6-chloro-N-hydroxyhexamethylene amide is 1:(2.01-2.03).

[0009] In step S1, the photoinitiator is 2,2-dimethoxy-2-phenylacetophenone.

[0010] The surfactant is prepared by the following method: N1: (1-Methylpyrrolidine-2,2-diyl)diethanol reacts with methacryl chloride to produce intermediate A, and the reaction equation is shown below: N2: Intermediate A reacts with 5-amino-1-mercaptopentane to generate intermediate B, as shown in the following schematic equation: N3: Intermediate B reacts with stearic acid to form a surfactant. The reaction equation is shown below:

[0011] In step N1, the molar ratio of (1-methylpyrrolidine-2,2-diyl)diethanol to methacryloyl chloride is 1:2.02.

[0012] In step N2, the molar ratio of intermediate A to 5-amino-1-mercaptopentane is 1:2.04.

[0013] In step N3, the molar ratio of intermediate B to stearic acid is 1:2.05.

[0014] A method for preparing a dewaxed transparent formulation includes the following steps: (1) Weigh out the following by weight: 8-12 parts of iso-octadecyl alcohol, 10-15 parts of n-nonane, 6-10 parts of n-octane, 15-25 parts of white oil, 2-5 parts of castor oil, 1-3 parts of surfactant, and 0.1-0.3 parts of anti-aging agent; (2) Add the above raw materials to the mixer in sequence and stir until well mixed to obtain the dewaxed transparent preparation.

[0015] Application of a dewaxing and clarifying agent in paraffin sheet preparation.

[0016] Due to the adoption of the above technical solutions, the beneficial effects of the present invention include: The dewaxed transparent formulation prepared by this invention exhibits a rapid wax dissolution rate, a high saturated wax dissolution capacity, and excellent anti-aging properties. The anti-aging agent added to the components for preparing the dewaxed transparent formulation enhances the formulation's anti-aging properties through the synergistic effect of thioester structures, secondary amine groups, hydroxamic acid structures, and hydrophobic long alkyl chains; the added surfactant enhances the wax dissolution rate and saturated wax dissolution capacity through the synergistic effect of pyrrolidine rings, ester groups, thioether bonds, amide bonds, and long-chain alkyl structures. Attached Figure Description

[0017] Figure 1 The image shows the proton NMR spectrum of the anti-aging agent prepared in Example 1.

[0018] Figure 2 The image shows a high-resolution mass spectrum of the anti-aging agent prepared in Example 1.

[0019] Figure 3 The image shows the proton NMR spectrum of the surfactant prepared in Example 4.

[0020] Figure 4 This is a high-resolution mass spectrum of the surfactant prepared in Example 4. Detailed Implementation

[0021] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to these embodiments.

[0022] Example 1: Preparation of Anti-aging Agent S1: Under nitrogen protection, 400 ml of tetrahydrofuran, 0.1 mol of (Z,Z)-3,3-thiodipropionate di(9-octadecenyl) ester, 0.202 mol of 5-amino-1-mercaptopentane, and 1.03 g of 2,2-dimethoxy-2-phenylacetophenone were stirred and mixed thoroughly at room temperature under an intensity of 100 mW / cm. 2 Irradiated with 365 nm ultraviolet light for 40 min, rotary evaporated at 40 °C to constant weight, added 300 ml of cold n-hexane and stirred to precipitate, filtered, the filter cake was washed with 80 ml of cold n-hexane and dried under vacuum at 40 °C for 12 h to obtain intermediate 1; its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 4.19-4.03 (m, 4H), 2.97-2.89(m, 4H), 2.87-2.75 (m, 2H), 2.73-2.46 (m, 12H), 1.75 (d, J = 2.7 Hz, 4H), 1.70-1.26 (m, 72H), 0.90 (t, J = 6.2 Hz, 6H); HRMS (m / z):917.7162[M+H] + ; S2: Under nitrogen protection, 650 ml of acetonitrile, 0.1 mol of intermediate 1, 0.201 mol of 6-chloro-N-hydroxyhexamethylenetetramine, and 0.205 mol of triethylamine were stirred and mixed. The mixture was heated to 55 °C and reacted for 8 h. After cooling to room temperature, the mixture was filtered and rotary evaporated at 50 °C to constant weight. The final weight was determined by distillation with a mixture of 350 ml of ethyl acetate and anhydrous ethanol (V... 乙酸乙酯 :V 无水乙醇 =8:2) recrystallized, filtered, and vacuum dried at 50℃ for 12 h to obtain the anti-aging agent; its proton NMR spectrum is shown below. Figure 1 As shown, the proton NMR data are as follows: 1 H NMR (400 MHz, Chloroform- dδ 9.12 (s, 2H), 9.06 (s, 2H), 4.19–4.03 (m, 4H), 2.97–2.83 (m, 4H), 2.82–2.79 (m, 2H), 2.78–2.68 (m, 8H), 2.65 (d, J = 2.4 Hz, 2H), 2.64–2.47 (m, 8H), 2.34–2.22 (m, 4H), 1.71–1.43 (m, 28H), 1.40–1.26 (m, 56H), 0.90 (t, J = 6.2 Hz, 6H); its high-resolution mass spectrum is shown below. Figure 2 The mass spectrometry data are as follows: HRMS (m / z): 1175.8743 [M+H] + .

[0023] Example 2 Preparation of Anti-aging Agent S1: Under nitrogen protection, 400 ml of tetrahydrofuran, 0.1 mol of (Z,Z)-3,3-thiodipropionate di(9-octadecenyl) ester, 0.203 mol of 5-amino-1-mercaptopentane, and 1.03 g of 2,2-dimethoxy-2-phenylacetophenone were stirred and mixed thoroughly at room temperature under an intensity of 100 mW / cm². 2 Irradiate under 365nm ultraviolet light for 40 min, evaporate at 40℃ to constant weight, add 300ml of cold n-hexane and stir to precipitate, filter, wash the filter cake with 80ml of cold n-hexane, and vacuum dry at 40℃ for 12 h to obtain intermediate 1. S2: Under nitrogen protection, 650 ml of acetonitrile, 0.1 mol of intermediate 1, 0.202 mol of 6-chloro-N-hydroxyhexamethylenetetramine, and 0.205 mol of triethylamine were stirred and mixed. The mixture was heated to 60 °C and reacted for 7 h. After cooling to room temperature, the mixture was filtered and rotary evaporated at 50 °C to constant weight. The final weight was determined by distillation with a mixture of 350 ml of ethyl acetate and anhydrous ethanol (V... 乙酸乙酯 :V 无水乙醇 The mixture was recrystallized (8:2 ratio), filtered, and vacuum dried at 50°C for 12 hours to obtain the anti-aging agent.

[0024] Example 3 Preparation of Anti-aging Agent S1: Under nitrogen protection, 400 ml of tetrahydrofuran, 0.1 mol of (Z,Z)-3,3-thiodipropionate di(9-octadecenyl) ester, 0.205 mol of 5-amino-1-mercaptopentane, and 1.03 g of 2,2-dimethoxy-2-phenylacetophenone were stirred and mixed thoroughly at room temperature under an intensity of 100 mW / cm². 2Irradiate under 365nm ultraviolet light for 40 min, evaporate at 40℃ to constant weight, add 300ml of cold n-hexane and stir to precipitate, filter, wash the filter cake with 80ml of cold n-hexane, and vacuum dry at 40℃ for 12 h to obtain intermediate 1. S2: Under nitrogen protection, 650 ml of acetonitrile, 0.1 mol of intermediate 1, 0.203 mol of 6-chloro-N-hydroxyhexamethylenetetramine, and 0.205 mol of triethylamine were stirred and mixed. The mixture was heated to 65 °C and reacted for 6 h. After cooling to room temperature, it was filtered and rotary evaporated at 50 °C to constant weight. The final weight was determined by distillation with a mixture of 350 ml of ethyl acetate and anhydrous ethanol (V... 乙酸乙酯 :V 无水乙醇 The mixture was recrystallized (8:2 ratio), filtered, and vacuum dried at 50°C for 12 hours to obtain the anti-aging agent.

[0025] Example 4 Preparation of Surfactants N1: Under nitrogen protection, 250 mL of dichloromethane, 0.1 mol of (1-methylpyrrolidine-2,2-diyl)diethanol, 0.2 mmol of hydroquinone, and 0.205 mol of triethylamine were stirred and mixed. 0.202 mol of methacryloyl chloride was added dropwise over 30 min. The reaction was carried out at 0 °C for 2 h, then the temperature was raised to 25 °C and the reaction continued for 24 h. The mixture was filtered, washed successively with 50 mL of deionized water, 50 mL of 5 wt% sodium bicarbonate solution, and 50 mL of saturated sodium chloride solution, dried over 50 g of anhydrous magnesium sulfate, rotary evaporated at 30 °C to constant weight, and then vacuum dried at 50 °C for 12 h to obtain intermediate A. Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 5.99 (d, J =12.4 Hz, 2H), 5.72 (d, J = 12.4 Hz, 2H), 4.16 (d, J = 2.6 Hz, 4H), 2.80-2.64(m, 2H), 2.44 (s, 3H), 1.91 (s, 6H), 1.90-1.64 (m, 4H); HRMS (m / z):282.1631[M+H] + ; Under nitrogen protection, 250 ml of tetrahydrofuran, 0.1 mol of intermediate A, 0.204 mol of 5-amino-1-mercaptopentane, and 1.03 g of 2,2-dimethoxy-2-phenylacetophenone were stirred and mixed thoroughly at room temperature under an intensity of 20 mW / cm². 2 Irradiated with 365 nm ultraviolet light for 40 min, rotary evaporated at 40 °C to constant weight, added 150 ml of cold n-hexane and stirred to precipitate, filtered, the filter cake was washed with 80 ml of cold n-hexane and dried under vacuum at 40 °C for 12 h to obtain intermediate B; its 1H NMR data are as follows: 1H NMR (400MHz, Chloroform- d ) δ 4.22-4.10 (m, 4H), 3.04-2.90 (m, 4H), 2.88 (d, J = 2.7Hz, 2H), 2.79-2.65 (m, 6H), 2.55-2.45 (m, 4H), 2.44 (s, 3H), HRMS (m / z):520.3169[M+H] + ; N3: Under nitrogen protection, 700 ml of dichloromethane, 0.205 mol of stearic acid, 45.8 g of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 25.2 g of N-hydroxysuccinimide were stirred and mixed. 0.1 mol of intermediate B was added, and the mixture was reacted at room temperature for 12 h. After filtration, the mixture was rotary evaporated at 30 °C to constant weight. The crude product was purified by silica gel chromatography (V... 二氯甲烷 :V 甲醇 =10:1), evaporated at 30℃ to constant weight to obtain the surfactant; its proton NMR spectrum is as follows. Figure 3 As shown, the proton NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 6.32 (s, 2H), 4.22-4.10 (m, 4H), 3.15 (dd, J = 1.0, 1.5 Hz, 4H), 3.04-2.90 (m, 4H), 2.88 (d, J = 2.7 Hz, 2H), 2.79-2.66 (m, 2H), 2.55-2.45 (m, 4H), 2.43 (d, J = 2.8 Hz, 3H), 2.19-2.10 (m, 4H), 1.73 (d, J = 4.0Hz, 4H), 1.63-1.45 (m, 12H), 1.39-1.26 (m, 60H), 1.24 (d, J = 6.2 Hz, 6H), 0.90 (t, J = 6.3 Hz, 6H); its high-resolution mass spectrum is as follows: Figure 4 The mass spectrometry data are as follows: HRMS (m / z): 1052.8387 [M+H] + .

[0026] Example 5: Preparation of dewaxed transparent formulation (1) Weigh the following by weight: 40g of iso-octadecanol, 50g of n-nonane, 30g of n-octane, 75g of white oil, 10g of castor oil, 5g of surfactant (prepared in Example 4), and 0.5g of anti-aging agent (prepared in Example 1); (2) Add iso-octadecanol, n-nonane, n-octane, white oil, castor oil, surfactant and anti-aging agent to a stirred reactor in sequence, stir at 300 rpm for 20 min to obtain a dewaxed transparent preparation.

[0027] Example 6 Preparation of dewaxed transparent formulation (1) Weigh the following by weight: 50g of iso-octadecanol, 60g of n-nonane, 40g of n-octane, 100g of white oil, 15g of castor oil, 10g of surfactant (prepared in Example 4), and 1g of anti-aging agent (prepared in Example 2); (2) Add iso-octadecanol, n-nonane, n-octane, white oil, castor oil, surfactant and anti-aging agent to a stirred reactor in sequence, stir at 300 rpm for 20 min to obtain a dewaxed transparent preparation.

[0028] Example 7 Preparation of dewaxed transparent formulation (1) Weigh the following by weight: 60g of iso-octadecanol, 75g of n-nonane, 50g of n-octane, 125g of white oil, 25g of castor oil, 15g of surfactant (prepared in Example 4), and 1.5g of anti-aging agent (prepared in Example 3); (2) Add iso-octadecanol, n-nonane, n-octane, white oil, castor oil, surfactant and anti-aging agent to a stirred reactor in sequence, stir at 300 rpm for 20 min to obtain a dewaxed transparent preparation.

[0029] Comparative Example 1 The raw material composition and preparation method of the dewaxed transparent formulation are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 2, except that the (Z,Z)-3,3-thiodipropionate di(9-octadecenyl) ester in step S1 is replaced with 0.2 mol of (Z)-3-[[3-(octadec-9-enyloxy)-3-oxopropyl]thio]propionic acid (CAS No. 83438-56-6); the amount of 6-chloro-N-hydroxyhexamethylene amide in step S2 is replaced with 0.101 mol, and the amount of triethylamine is replaced with 0.105 mol.

[0030] Comparative Example 2 The raw material composition and preparation method of the dewaxed transparent formulation are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 2, except that 5-amino-1-mercaptopentane in step S1 is replaced with an equimolar amount of mercaptoethylamine.

[0031] Comparative Example 3 The raw material composition and preparation method of the dewaxed transparent formulation are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 2, except that 6-chloro-N-hydroxyhexamamide in step S2 is replaced with an equimolar amount of 2-chloroacetoxyoxime acid.

[0032] Comparative Example 4 The raw material composition and preparation method of the dewaxed transparent formulation are basically the same as those in Example 6, except that the anti-aging agent is replaced with an equal weight of an anti-aging agent prepared by the following method: The preparation method of the anti-aging agent is basically the same as that in Example 2, except that the amount of 6-chloro-N-hydroxyhexamethylene amide in step S2 is replaced with 0.101 mol.

[0033] Comparative Example 5 The raw material composition and preparation method of the dewaxed transparent formulation are basically the same as those in Example 6, except that the surfactant is replaced with an equal weight of a surfactant prepared by the following method: The preparation method of the surfactant is basically the same as that in Example 4, except that (1-methylpyrrolidine-2,2-diyl)diethanol in step N1 is replaced with 0.2 mol of 1-methyl-2-pyrrolidineethanol; the amount of 5-amino-1-mercaptopentane in step N2 is replaced with 0.102 mol; the amount of stearic acid in step N3 is replaced with 0.102 mol, the amount of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride is replaced with 22.9 g, and the amount of N-hydroxysuccinimide is replaced with 12.6 g.

[0034] Comparative Example 6 The raw material composition and preparation method of the dewaxed transparent formulation are basically the same as those in Example 6, except that the surfactant is replaced with an equal weight of a surfactant prepared by the following method: The preparation method of the surfactant is basically the same as that in Example 4, except that the stearic acid in step N3 is replaced with an equimolar amount of octanoic acid.

[0035] Comparative Example 7 The raw material composition and preparation method of the dewaxed transparent formulation are basically the same as those in Example 6, except that the surfactant is replaced with an equal weight of a surfactant prepared by the following method: The preparation method of the surfactant is basically the same as that in Example 4, except that the amount of stearic acid in step N3 is replaced with 0.102 mol.

[0036] The white oil used in the embodiments and comparative examples of this application is 46# white oil, produced by Hengshui Jingjiu Lubricating Oil Co., Ltd.; the castor oil is Crystal type. ® LC; CAS number for 6-chloro-N-hydroxyhexamethylenediamide is 64214-53-5; CAS number for (1-methylpyrrolidine-2,2-diyl)diethanol is 111722-58-8.

[0037] The dewaxed transparent formulations prepared in Examples 5-7 and Comparative Examples 1-7 were tested for wax dissolution rate, saturated wax dissolution amount, and anti-aging properties. The test results are shown in Table 1.

[0038] Determination of paraffin dissolution rate: Weigh 10g of medical-grade paraffin slices and place them in a 50ml beaker. Place the beaker in an oven at 70℃ for 30min to completely dissolve the paraffin. After removal, allow the paraffin to cool naturally and solidify. Add 30ml of the dewaxed transparent preparation prepared in the examples or comparative examples, and stir at 120r / min at 25℃. Record the time it takes for the paraffin to completely dissolve (no observable solid particles). Calculate the paraffin dissolution rate according to the following formula: ; In the formula, S: paraffin dissolution rate, mg / (ml·min); m: mass of paraffin added, mg; V: volume of the dewaxed transparent preparation, ml; t: time for complete dissolution of paraffin, min.

[0039] Anti-aging performance test: 30ml of dewaxed transparent formulation was placed in a QUV accelerated aging test chamber for aging test. The irradiation wavelength was 310nm and the irradiation intensity was 0.89W / m. 2 The temperature was 60℃ and the aging time was 800h. The wax dissolution rate of the dewaxed transparent formulation after aging was measured again.

[0040] Determination of saturated paraffin content: Weigh 30g of medical-grade paraffin slices and place them in a 150ml beaker. Place the beaker in an oven at 70℃ for 30 minutes to completely dissolve the paraffin. After removing the beaker, allow it to cool naturally to solidify. Add 30ml of dewaxing and clarifying agent and place the beaker in a 35℃ constant temperature water bath for 12 hours. Filter the beaker and vacuum dry the filter cake at 45℃ to constant weight. Weigh the remaining paraffin and calculate the saturated paraffin content using the following formula: ; In the formula, c: saturated wax content, mg / ml; Mass of paraffin added, mg; : Remaining paraffin mass, mg; V: Volume of the dewaxed and transparent preparation, ml.

[0041] Table 1 Performance Test Data As can be seen from Table 1, the dewaxed transparent formulations prepared in Examples 5-7 of this application have a fast wax dissolution rate, a high saturated wax dissolution amount, and excellent anti-aging properties.

[0042] The anti-aging agent molecules added to the dewaxed transparent formulation prepared in this application simultaneously introduce thioester structures, secondary amine groups, hydroxamic acid structures, and hydrophobic long alkyl chains. These functional structures form a multi-pathway synergistic antioxidant mechanism in the system. During the use and storage of the dewaxed transparent formulation, components such as white oil and castor oil in the system are prone to auto-oxidation reactions under the influence of heat, light, and air, generating hydroperoxides and related free radical intermediates. The thioester structure in the anti-aging agent molecule serves as the main antioxidant functional unit, preferentially reacting with the hydroperoxides generated in the system, reducing and decomposing them into relatively stable alcohols. This effectively inhibits the accumulation of hydroperoxides and their further decomposition to generate alkoxy and peroxy radicals. The secondary amine structure, as an auxiliary anti-aging unit, can react with the small amount of free radicals generated in the system, terminating the free radical chain reaction through hydrogen donors or electron transfer. This synergistic effect with the decomposition of peroxides by the thioester enhances the oxidation stability of the system. Simultaneously, the hydroxamic acid structure, as a potent metal chelator, can firmly complex trace transition metal ions that may be present in the formulation, fundamentally inhibiting metal-catalyzed oxidation reactions. The hydrophobic long alkyl chain significantly improves the compatibility and dispersion stability of this anti-aging agent in solvents such as alkanes, white oils, and alcohols, reducing migration or precipitation, allowing it to remain stable and continuously function in dewaxed transparent formulations. The synergistic effect of various functional structures in the anti-aging agent molecule, through a multifunctional synergistic mechanism of "thioester-dominated decomposition of peroxides—secondary amine-assisted free radical scavenging—hydroxamic acid inhibition of metal catalysis—long-chain structure enhancing compatibility and stability," significantly improves the anti-aging stability of dewaxed transparent formulations during storage and use, extending the effective service life of the formulation. In Comparative Example 1, the anti-aging agent used had reduced thioester, long-chain alkyl, secondary amine, and hydroxamic acid structures, leading to a weakening of the key pathway for peroxide decomposition, the synergistic effect of free radical scavenging, and the metal chelating ability. This resulted in a significant decrease in the formulation's ability to block oxidation chain reactions, the efficiency of intermediate product scavenging, and the inhibitory effect of metal-catalyzed oxidation, ultimately manifesting as a decline in anti-aging performance.

[0043] The surfactant added to the dewaxing and transparent formulation prepared in this application uses a pyrrolidine ring as a rigid core. By symmetrically introducing ester groups, thioether bonds, amide bonds, and long-chain alkyl structures, the synergistic effect of multiple groups is achieved, significantly improving the wax dissolution rate and saturated wax dissolution amount of the dewaxing and transparent formulation. The long-chain alkyl groups at both ends of the surfactant molecule provide strong hydrophobic anchoring, ensuring uniform dispersion and deep penetration of the paraffin layer in the nonpolar alkane matrix. The rigid skeleton of the pyrrolidine ring causes the molecules to be tightly arranged at the wax-oil interface, effectively reducing interfacial tension and accelerating the wetting and swelling of paraffin by the solvent. The ester group disrupts the ordered arrangement of paraffin crystals through dipole interaction, and the thioether bond enhances the affinity for wax molecules with the lone pair electrons of the sulfur atom. The two work together to promote the exfoliation and dissolution of the wax layer. As a strongly polar group, the amide bond can self-assemble in the oil phase through intermolecular hydrogen bonds to form reverse micelles, stably encapsulating the dissolved wax molecules and preventing supersaturated precipitation, thereby increasing the saturated wax dissolution amount. The various structures in the surfactant comprehensively improve the dewaxing efficiency and saturated wax content of the dewaxing transparent formulation through multiple synergistic effects of "interfacial adsorption—reduction of surface tension—wax crystal disruption—micelle solubilization." In Comparative Example 5, the surfactant had half the number of ester groups, thioether bonds, amide bonds, and long-chain alkyl groups. This resulted in reduced anchoring and alignment efficiency at the interface, fewer interaction sites with wax molecules, and weakened reverse micellar solubilization ability. Consequently, its synergistic effects of reducing interfacial tension, disrupting wax crystal structure, and stabilizing wax molecule dissolution were significantly weakened, ultimately leading to a decrease in the wax dissolution rate and saturated wax content of the dewaxing transparent formulation.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. However, any modifications, alterations, and variations made by those skilled in the art without departing from the scope of the present invention based on the disclosed technical content are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A dewaxed transparent formulation, characterized in that, The ingredients include the following parts by weight: 8-12 parts of isomeric octadecanol, 10-15 parts of n-nonane, 6-10 parts of n-octane, 15-25 parts of white oil, 2-5 parts of castor oil, 1-3 parts of surfactant, and 0.1-0.3 parts of anti-aging agent; The anti-aging agent is prepared by the following method: S1: (Z,Z)-3,3-thiodipropionic acid di(9-octadecenyl) ester reacts with 5-amino-1-mercaptopentane under the action of a photoinitiator to generate intermediate 1. S2: Intermediate 1 reacts with 6-chloro-N-hydroxyhexamamide to generate an anti-aging agent.

2. The dewaxing and transparent formulation according to claim 1, characterized in that, In step S1, the molar ratio of (Z,Z)-3,3-thiodipropionate di(9-octadecenyl) ester to 5-amino-1-mercaptopentane is 1:(2.02-2.05).

3. The dewaxing and transparent formulation according to claim 1, characterized in that, In step S2, the molar ratio of intermediate 1 to 6-chloro-N-hydroxyhexamethylene amide is 1:(2.01-2.03).

4. The dewaxing and transparent formulation according to claim 1, characterized in that, In step S1, the photoinitiator is 2,2-dimethoxy-2-phenylacetophenone.

5. The dewaxing and transparent formulation according to claim 1, characterized in that, The surfactant is prepared by the following method: N1: (1-Methylpyrrolidine-2,2-diyl)diethanol reacts with methacryl chloride to produce intermediate A. N2: Intermediate A reacts with 5-amino-1-mercaptopentane to generate intermediate B. N3: Intermediate B reacts with stearic acid to generate a surfactant.

6. The dewaxing and transparent formulation according to claim 5, characterized in that, In step N1, the molar ratio of (1-methylpyrrolidine-2,2-diyl)diethanol to methacryloyl chloride is 1:2.

02.

7. The dewaxing and transparent formulation according to claim 5, characterized in that, In step N2, the molar ratio of intermediate A to 5-amino-1-mercaptopentane is 1:2.

04.

8. The dewaxing and transparent formulation according to claim 5, characterized in that, In step N3, the molar ratio of intermediate B to stearic acid is 1:2.

05.

9. A method for preparing a dewaxed transparent formulation according to any one of claims 1-8, characterized in that, Includes the following steps: (1) Weigh out the following by weight: 8-12 parts of iso-octadecyl alcohol, 10-15 parts of n-nonane, 6-10 parts of n-octane, 15-25 parts of white oil, 2-5 parts of castor oil, 1-3 parts of surfactant, and 0.1-0.3 parts of anti-aging agent; (2) Add the above raw materials to the mixer in sequence and stir until well mixed to obtain the dewaxed transparent preparation.

10. The use of a dewaxing and clearing formulation as described in any one of claims 1-8 in paraffin sheet preparation.

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