An ultra-long salt-fog-resistant storage composite base oil rust preventive and a preparation method thereof

Abstract

The application relates to the technical field of metal material corrosion prevention and long-term storage protection, and discloses a composite base oil rust-proof oil for super-long salt mist storage and a preparation method thereof. The rust-proof oil comprises synthetic isomeric alkane base oil, ester synthetic base oil, borate dynamic covalent topological entanglement-beta-cyclodextrin-adamantane host-guest lock synergistic modification material, L-arginine, rust-proof additives, antioxidants and leveling agents. The synergistic modification material constructs a reversible borate dynamic covalent topological entanglement network through benzene boronic acid and o-diphenol, and forms a host-guest lock structure through beta-cyclodextrin and adamantylamine, thereby forming a three-dimensional dynamic protection network structure in an oil phase system; through synergistic design, the protection film layer has dynamic rearrangement and self-stabilization ability in a salt mist environment, and the salt mist resistance time, the damp-heat stability and the film layer adhesion are significantly improved. The application has novel structure design, excellent protection effect and is suitable for long-term storage and high-salt-mist-environment protection of metal components.

Description

Technical Field

[0001] This invention relates to the field of corrosion protection and long-term storage protection technology for metal materials, specifically to a composite base oil rust inhibitor for ultra-long-term salt spray storage and its preparation method. Background Technology

[0002] Metal components exposed to high humidity and salt spray environments during marine transport, equipment storage, export transit, and long-term warehousing are highly susceptible to electrochemical corrosion, especially in the presence of Cl⁻. The passivation film on the metal surface is easily destroyed, and the corrosion reaction is continuously activated, leading to pitting corrosion, rust propagation, and structural performance degradation. To mitigate corrosion, industrially, rust-preventive oils are typically coated onto metal surfaces to form an isolation film for sealing and protection. Existing composite base oil rust-preventive oil systems are mostly composed of mineral or synthetic base oils, supplemented with petroleum sulfonate corrosion inhibitors, fatty acid polar adsorbents, and antioxidants. Their protective mechanism mainly relies on the physical isolation effect of the oil film and the adsorption and passivation effect of polar groups on the metal surface. However, the protective film formed by such systems is often a single adsorption structure or a simple complex structure, making it difficult to form a stable and dense three-dimensional network structure at the interface. In a salt spray environment, Cl⁻ ions easily penetrate the oil film layer, disrupting the adsorption balance and causing interfacial instability, resulting in a significant decrease in rust prevention effectiveness over time. Meanwhile, under long-term storage conditions, traditional oil films are prone to migration, flow, or local thinning. The protective structure lacks self-adjustment capabilities and is difficult to maintain a continuous and stable protective state. Salt spray protection time is usually difficult to exceed 3,000 hours, which is insufficient to meet the ultra-long-term storage requirements of high-end equipment and precision components.

[0003] In recent years, although some technologies have attempted to introduce silane coupling agents or polyphenol complexing agents to enhance interfacial binding, their modification methods still remain at the level of single chemical adsorption or simple coordination, lacking innovative mechanisms that can construct dynamic covalent networks and molecularly locked synergistic structures in oil-phase systems.

[0004] Therefore, developing a composite base oil rust inhibitor capable of forming a dynamic topological entanglement and subject-guest locking cooperative network in an oil film, and achieving structural self-weight rearrangement and self-stabilization in a salt spray environment, has become a key technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] To overcome the shortcomings of the traditional rust-preventive oil film layer in the aforementioned background technology, such as its simple structure and susceptibility to Cl- in salt spray environments... -Addressing the technical challenges of infiltration damage, insufficient long-term storage stability, and difficulty in overcoming protective lifespan limitations, this invention aims to provide an ultra-long-lasting salt spray resistant composite base oil rust inhibitor and its preparation method. This invention employs a three-dimensional synergistic protection system combining a dynamic covalent network constructed from borate ester dynamic topological entanglement-host-guest locking synergistic modified materials with a molecular-level inclusion-locking structure. Furthermore, the multi-point adsorption effect of L-arginine forms a self-rearranging and self-stabilizing interfacial protective network structure within the composite base oil system. This invention significantly improves the structural density and interfacial stability of the oil film, thereby achieving continuous protection performance under ultra-long salt spray environments.

[0006] The objective of this invention can be achieved through the following technical solutions: A composite base oil rust inhibitor for ultra-long-lasting salt spray resistance, comprising the following raw materials in parts by weight: 60-80 parts of synthetic isoalkane base oil; 10-25 parts of ester synthetic base oil; 3-12 parts of borate ester dynamic topological entanglement-host-guest locking synergistic modifier; 0.5-3.0 parts of L-arginine; 2-8 parts of calcium petroleum sulfonate; 1-5 parts of diisooctyl succinate; 1-5 parts of polyisobutylene; 0.1-0.5 parts of antioxidant; and 0.1-0.5 parts of leveling agent. The borate ester dynamic topological entanglement-host-guest locking synergistic modifier is a three-dimensional dynamic protective system formed by constructing a dynamic covalent topological entanglement network through a reversible borate esterification reaction of phenylboronic acid and catechol, and forming a molecular locking structure through host-guest inclusion interaction between β-cyclodextrin and adamantaneamine.

[0007] Optionally, the borate ester dynamic topological entanglement-host-guest locking synergistic modifier comprises the following raw materials in parts by weight: 1-5 parts phenylboronic acid; 1-6 parts catechol; 1-8 parts β-cyclodextrin; and 0.5-4 parts adamantane.

[0008] Optionally, the preparation method of the borate ester dynamic topological entanglement-host-guest locked synergistic modified material includes the following steps: (1) Add phenylboronic acid and catechol to an organic solvent and react under stirring to obtain a borate ester dynamic network precursor solution; (2) β-cyclodextrin was dissolved in a polar solvent, and adamantane was added. The mixture was then subjected to an inclusion complexation reaction under stirring to obtain a host-guest locked structure solution. (3) The borate ester dynamic network precursor solution is mixed with the host-guest locked structure solution and a composite reaction is carried out under stirring conditions to obtain the borate ester dynamic topological entanglement-host-guest locked synergistic modified material.

[0009] Optionally, the reaction conditions for step (1) are as follows: in anhydrous ethanol or tetrahydrofuran solvent, the temperature is controlled at 30-70°C, the stirring speed is 300-800 r / min, the reaction time is 1-4 h, and the water content of the system is controlled at 0.1-1.0%.

[0010] Optionally, the reaction conditions for step (2) are as follows: in water or a water-alcohol mixture, the temperature is controlled at 25-60℃, the stirring speed is 300-700r / min, the reaction time is 1-6h, and the pH of the system is 6-9.

[0011] Optionally, the reaction conditions for step (3) are: mixing and reacting at 40-80℃ for 1-5 hours, stirring at 400-900 r / min, removing the solvent under reduced pressure after the reaction and drying at 50-90℃ for 2-8 hours.

[0012] Optionally, the antioxidant is a mixture of hindered phenolic antioxidant 1010 and phosphite antioxidant 168 in a mass ratio of 1:0.5 to 1:2; the leveling agent is a mixture of polyether-modified polysiloxane and fluorinated acrylate in a mass ratio of 1:0.2 to 1:1.

[0013] Optionally, a composite base oil rust inhibitor for ultra-long-lasting salt spray resistance is prepared by means of the following steps: S1, a base oil system is obtained by mixing synthetic isoalkane base oil with ester synthetic base oil; S2, add borate ester dynamic topological entanglement-host-guest locking synergistic modifier to the base oil system for dispersion to obtain the modified base oil system; S3, L-arginine, calcium petroleum sulfonate, diisooctyl succinate, polyisobutylene, antioxidant and leveling agent are added sequentially to the modified base oil system, and the mixture is stirred evenly to obtain the composite base oil rust preventive oil.

[0014] Optionally, the reaction conditions for step S1 are a temperature of 50–80°C, a stirring speed of 300–600 r / min, and a time of 0.5–2 h; the reaction conditions for step S2 are a temperature of 60–90°C, a stirring speed of 600–1200 r / min, and a time of 0.5–2 h.

[0015] Optionally, the reaction conditions in step S3 are: temperature of 60–85°C, stirring speed of 400–800 r / min, and time of 1–3 h. After the reaction is completed, the mixture is filtered and cooled to room temperature.

[0016] The beneficial effects of this invention are: This invention constructs a synergistic system of a reversible dynamic covalent topological entanglement network of borate esters and a host-guest molecular locking structure of β-cyclodextrin-adamantane, enabling the protective film to possess dynamic rearrangement and self-repair capabilities under salt spray conditions. - It maintains the stability of the interface structure and continuously enhances the film density under continuous erosion conditions. At the same time, it significantly inhibits the migration and precipitation of modified components in the oil phase through molecular-level inclusion locking, thereby achieving an ultra-long-term salt spray protection effect that prevents the protective structure from loosening or leaking and maintains high stability under long-term storage conditions. Attached Figure Description

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] Figure 1 Infrared spectra comparison of the physical mixed precursor system of phenylboronic acid-catechol-β-cyclodextrin-adamantane and the host-guest locked synergistic modified material of borate ester with dynamic covalent topological entanglement-β-cyclodextrin-adamantane. Figure 2 A comparison chart showing the salt spray failure time of samples with different formulations. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. Equivalent adjustments made without departing from the spirit and essence of the present invention should also be considered to fall within the protection scope of the present invention.

[0020] Example 1: This example is used to verify that when the amount of each component and the reaction conditions are all within the lower limit range, a stable dynamic covalent topological entanglement structure of borate ester and a host-guest locked structure synergistic network can still be formed.

[0021] Preparation method Preparation of S1, a synergistically modified material with dynamic covalent topological entanglement of borate esters, β-cyclodextrin, and adamantane host-guest locking. One part of phenylboronic acid and one part of catechol were added to anhydrous ethanol and stirred at 300 r / min for 1 h at 30 °C. The water content of the system was controlled to be 0.1%, so that phenylboronic acid and catechol underwent a reversible borate esterification reaction to form a precursor solution of dynamic covalent topological entanglement network. One part of β-cyclodextrin was added to an aqueous solvent and stirred at 300 r / min at 25 °C to dissolve it. Then, 0.5 parts of adamantane were added and reacted for 1 h. The pH of the system was 6, forming a β-cyclodextrin-adamantane host-guest locked structure solution. The two systems were mixed and reacted at 400 r / min at 40 °C for 1 h. After desolventizing under reduced pressure, the mixture was dried at 50 °C for 2 h to obtain three parts of the borate ester dynamic covalent topological entanglement-β-cyclodextrin-adamantane host-guest locked synergistic modified material. S2, Base Oil System Construction 60 parts of synthetic isoalkane base oil and 10 parts of ester synthetic base oil were added to a reaction vessel and stirred at 300 r / min for 0.5 h at 50 °C to obtain a homogeneous base oil system. S3, Preparation of Composite Rust-Preventive Oil Add 3 parts of the above-mentioned synergistic modifier to the base oil system and disperse it at 600 r / min for 0.5 h at 60℃. Then add 0.5 parts of L-arginine, 2 parts of calcium petroleum sulfonate, 1 part of diisooctyl succinate, 1 part of polyisobutylene, 0.1 parts of antioxidant and 0.1 parts of leveling agent in sequence. React at 400 r / min for 1 h at 60℃, filter and cool to obtain the composite base oil rust preventive oil for ultra-long salt spray resistance.

[0022] Example 2: This example is used to verify that when the components and reaction conditions are within the recommended median range, the dynamic topological entanglement network density and the degree of subject-guest locking achieve the optimal balance between structural integrity and salt spray protection stability.

[0023] Preparation method S1, Preparation of synergistically modified materials Three parts of phenylboronic acid and three parts of catechol were added to tetrahydrofuran and stirred at 600 r / min for 2 h at 50 °C, with the water content of the system controlled at 0.5%, to construct a dynamic covalent topological entanglement network precursor system. Four parts of β-cyclodextrin were added to a water-alcohol mixed solvent and stirred at 500 r / min at 40 °C to dissolve. Two parts of adamantane were added and reacted for 3 h, with the pH of the system set at 7, to form a host-guest locked structure. The two systems were mixed and reacted at 700 r / min at 60 °C for 3 h, desolventized under reduced pressure, and dried at 70 °C for 5 h to obtain seven parts of the borate ester dynamic covalent topological entanglement-β-cyclodextrin-adamantane host-guest locked synergistic modified material. Figure 1 As can be seen from the infrared spectrum comparison, the unmodified sample at 3400 cm⁻¹ -1 A strong and broad O–H stretching vibration peak is observed nearby, with a peak at 1410 cm⁻¹. -1 With 1335 cm -1 A distinct B–OH-related characteristic peak can be observed at this location; in the modified sample, the peak intensity in this region is significantly reduced and undergoes a slight red shift, indicating that the phenolic hydroxyl group undergoes a reversible borate esterification reaction with the boric acid group; at 1345 cm⁻¹ -1 and 1325 cm -1 The appearance of a new B–O–C characteristic absorption peak at the point indicates the formation of borate ester bonds; the slight change in the position of the C–O–C absorption peak of β-cyclodextrin indicates a change in the host-guest inclusion environment; the overall spectrum shows that the system has changed from a physically mixed state to a synergistic modified structure with a dynamic covalent network and host-guest locking structure. S2, Base Oil System Construction 70 parts of synthetic isoalkane base oil and 18 parts of ester synthetic base oil were added to a reaction vessel and stirred at 450 r / min for 1 h at 65℃. S3, Preparation of Composite Rust-Preventive Oil Add 7 parts of the above-mentioned synergistic modifier to the base oil system and disperse it at 800 r / min for 1 h at 75℃; then add 2 parts of L-arginine, 5 parts of calcium petroleum sulfonate, 3 parts of diisooctyl succinate, 3 parts of polyisobutylene, 0.3 parts of antioxidant and 0.3 parts of leveling agent in sequence, react at 600 r / min for 2 h at 75℃, filter and cool to obtain rust-preventive oil.

[0024] Example 3: This example is used to verify the effect of maximizing the density of dynamic covalent topological entanglement network and host-guest locked structure on the enhancement of film stability and salt spray resistance when the dosage of each component and reaction conditions are within the upper limit range.

[0025] Preparation method S1, Preparation of synergistically modified materials Five parts of phenylboronic acid and six parts of catechol were added to anhydrous ethanol and stirred at 800 r / min for 4 h at 70 °C, with the water content of the system controlled at 1.0%, to form a high-density dynamic covalent topological entanglement network precursor system. Eight parts of β-cyclodextrin were added to a water-alcohol mixed solvent and stirred at 700 r / min at 60 °C to dissolve. Four parts of adamantane were added and reacted for 6 h, with the pH of the system being 9, to form a high inclusion density host-guest locked structure. The two systems were mixed and reacted at 900 r / min at 80 °C for 5 h. After desolventizing under reduced pressure, the mixture was dried at 90 °C for 8 h to obtain 12 parts of borate ester dynamic covalent topological entanglement-β-cyclodextrin-adamantane host-guest locked synergistic modified material. S2, Base Oil System Construction 80 parts of synthetic isoalkane base oil and 25 parts of ester synthetic base oil were added to a reaction vessel and stirred at 600 r / min for 2 hours at 80°C. S3, Preparation of Composite Rust-Preventive Oil Add 12 parts of the above-mentioned synergistic modifier to the base oil system and disperse it at 1200 r / min for 2 hours at 85°C. Then add 3 parts of L-arginine, 8 parts of calcium petroleum sulfonate, 5 parts of diisooctyl succinate, 5 parts of polyisobutylene, 0.5 parts of antioxidant and 0.5 parts of leveling agent in sequence. React at 800 r / min for 3 hours at 85°C. Filter and cool to obtain the rust-preventive oil.

[0026] Comparative Example 1: This comparative example is used to verify the effect of using only the dynamic covalent topological entanglement structure of borate ester for single modification on the stability of salt spray protection.

[0027] Preparation method S1, Preparation of a single modified substance 3.5 parts of phenylboronic acid and 3.5 parts of catechol were added to tetrahydrofuran and stirred at 600 r / min for 2 h at 50 °C. The water content of the system was controlled to be 0.5% to construct a precursor system of dynamic covalent topological entanglement network of borate ester. After the reaction was completed, the solvent was removed under reduced pressure and dried at 70 °C for 5 h to obtain 7 parts of single modified material of dynamic covalent topological entanglement of borate ester. S2, Base Oil System Construction 70 parts of synthetic isoalkane base oil and 18 parts of ester synthetic base oil were added to a reaction vessel and stirred at 450 r / min for 1 h at 65℃. S3, Preparation of Composite Rust-Preventive Oil Seven parts of the above-mentioned borate ester dynamic covalent topological entanglement single modifier were added to the base oil system and dispersed at 800 r / min for 1 h at 75℃. Subsequently, two parts of L-arginine, five parts of calcium petroleum sulfonate, three parts of diisooctyl succinate, three parts of polyisobutylene, 0.3 parts of antioxidant and 0.3 parts of leveling agent were added in sequence and reacted at 600 r / min for 2 h at 75℃. After filtration and cooling, the rust-preventive oil was obtained.

[0028] Comparative Example 2: This comparative example is used to verify the effect of using only the β-cyclodextrin-adamantane host-guest locked structure for single modification on the stability of salt spray protection.

[0029] Preparation method S1, Preparation of a single modified substance Five parts of β-cyclodextrin were added to a water-alcohol mixed solvent and dissolved by stirring at 500 r / min at 40℃. Two parts of adamantane were added and reacted for 3 h. The pH of the system was 7, forming a β-cyclodextrin-adamantane host-guest locked structure. After the reaction was completed, the solvent was removed under reduced pressure and dried at 70℃ for 5 h to obtain seven parts of β-cyclodextrin-adamantane host-guest locked single modified material. S2, Base Oil System Construction 70 parts of synthetic isoalkane base oil and 18 parts of ester synthetic base oil were added to a reaction vessel and stirred at 450 r / min for 1 h at 65℃. S3, Preparation of Composite Rust-Preventive Oil Seven parts of the above-mentioned β-cyclodextrin-adamantane host-guest locked single modified substance were added to the base oil system and dispersed at 800 r / min for 1 h at 75℃. Subsequently, two parts of L-arginine, five parts of calcium petroleum sulfonate, three parts of diisooctyl succinate, three parts of polyisobutylene, 0.3 parts of antioxidant and 0.3 parts of leveling agent were added in sequence and reacted at 600 r / min for 2 h at 75℃. After filtration and cooling, the rust-preventive oil was obtained.

[0030] Comparative Example 3: This comparative example is used to verify the effect of not adding organic small molecule L-arginine on the stability of salt spray protection while keeping the synergistic modifier unchanged.

[0031] Preparation method S1, Preparation of synergistically modified materials Three parts of phenylboronic acid and three parts of catechol were added to tetrahydrofuran and stirred at 600 r / min for 2 h at 50 °C, with the water content of the system controlled at 0.5%, to construct a dynamic covalent topological entanglement network precursor system. Four parts of β-cyclodextrin were added to a water-alcohol mixed solvent and stirred at 500 r / min at 40 °C to dissolve. Two parts of adamantane were added and reacted for 3 h, with the pH of the system set at 7, to form a host-guest locked structure. The two systems were mixed and reacted at 700 r / min at 60 °C for 3 h, desolventized under reduced pressure, and dried at 70 °C for 5 h to obtain seven parts of the borate ester dynamic covalent topological entanglement-β-cyclodextrin-adamantane host-guest locked synergistic modified material. S2, Base Oil System Construction 72 parts of synthetic isoalkane base oil and 18 parts of ester synthetic base oil were added to a reaction vessel and stirred at 450 r / min for 1 h at 65℃. S3, Preparation of Composite Rust-Preventive Oil Add 7 parts of the above-mentioned synergistic modifier to the base oil system and disperse it at 800 r / min for 1 h at 75℃; then add 5 parts of calcium petroleum sulfonate, 3 parts of diisooctyl succinate, 3 parts of polyisobutylene, 0.3 parts of antioxidant and 0.3 parts of leveling agent in sequence, react at 600 r / min for 2 h at 75℃, filter and cool to obtain rust-preventive oil.

[0032] Performance testing: 1. Neutral salt spray test The salt spray corrosion resistance of the rust-preventive oils in each example and comparative example was evaluated using a neutral salt spray test. Q235 carbon steel test plates, measuring 150 mm × 70 mm × 3 mm, were selected after sandblasting and cleaning with anhydrous ethanol and drying. Each sample was uniformly coated onto the surface of the test plate, forming an oil film with a thickness of 15–25 μm. After standing for 24 hours, the test was conducted. Following GB / T 10125 standard, a 5% sodium chloride solution was sprayed in a salt spray chamber at a controlled temperature of 35 ± 1℃ and a solution pH of 6.5–7.2, with continuous spraying. The corrosion condition of the test plate surface was observed every 24 hours. The time when the area of ​​continuous rust spots exceeded 5% was defined as the salt spray failure time, used to compare the differences in salt spray resistance among the samples.

[0033] 2. Stability test under damp heat cycling To evaluate the long-term stability of the protective film under high humidity conditions, the coated steel plates were placed in a constant temperature and humidity chamber for a damp heat cycling test. The test conditions were: temperature 40±1℃, relative humidity 95±2%, with each cycle lasting 24 hours, and continuous operation. During the test, the surface condition of the oil film and corrosion were observed every 72 hours, and the time when obvious rust spots, oil film flow, or cracking appeared was recorded. By comparing the film stability time of the examples and comparative examples under damp heat conditions, the contribution of the synergistic modified structure to interface stability was evaluated.

[0034] 3. Electrochemical impedance spectroscopy (EIS) Electrochemical impedance spectroscopy (EIS) was performed on the coated samples using an electrochemical workstation to evaluate the shielding capability of the protective film. A steel plate coated with rust-preventive oil was used as the working electrode, a platinum sheet as the counter electrode, and a saturated calomel electrode as the reference electrode. The test was conducted in a 3.5% sodium chloride solution. The frequency range was set to 10 Hz. 5 The impedance range is from Hz to 10⁻² Hz, with a perturbation voltage of 10 mV. Parameters such as coating resistance (Rcoat) and charge transfer resistance (Rct) were obtained through fitting. Higher impedance moduli in the low-frequency region indicate a denser protective film and superior interface shielding performance. The synergistic protective effect of dynamic topological entanglement and host-guest locking structures was analyzed by comparing the impedance variation trends of different samples.

[0035] 4. Oil film adhesion and migration stability test To evaluate the adhesion stability and migration trend of the oil film on the metal surface, the coated samples were left to stand at room temperature for 7 days, and then the adhesion was tested using the cross-cut adhesion test, and graded according to GB / T 9286 standard. Simultaneously, the test plates were placed at an angle in a 60℃ constant temperature chamber for 48 hours, and the changes in oil film flow length and thickness were observed, and the oil film migration rate was measured. A lower migration rate and a higher adhesion grade indicate a more stable film structure. By comparing the adhesion grades and migration rates of the examples and comparative examples, the role of the synergistic modified structure in inhibiting component migration and enhancing interfacial stability was verified.

[0036] Table 1 Comparison of Comprehensive Performance Test Results As shown in Table 1, Example 2 exhibits the best performance in key indicators such as salt spray failure time, damp heat stabilization time, low-frequency impedance modulus, adhesion level, and migration rate. Its salt spray failure time reaches 120 h, which is significantly higher than that of Examples 1 and 3, and also much higher than that of the comparative examples. This indicates that the boronic acid ester dynamic covalent topological entanglement structure and the β-cyclodextrin-adamantane host-guest locking structure constructed within the recommended median range can form the most stable and dense interface protection network structure.

[0037] In terms of salt spray performance, Examples 1 and 3 achieved 120 h and 72 h respectively, both significantly better than Comparative Examples 1, 2, and 3, indicating that as long as a complete synergistic modification system is formed, the long-term protection capability under Cl⁻ environment can be significantly improved. However, Comparative Examples 1 and 2, when using only a single modification method, Figure 2 The significant decrease in salt spray time indicates that neither a single dynamic borate ester network nor a single host-guest structure can construct a stable and durable protective layer.

[0038] The results of the wet-heat cycling show that Example 2 can maintain a stable film layer without significant failure for 680 h under high humidity conditions, and the film layer is stable without flow, demonstrating the significant enhancement effect of dynamic topological network and molecular locking structure on the stability of oil film structure. In contrast, the wet-heat failure time of Comparative Example 3 is reduced to 240 h under the condition of lacking L-arginine, indicating that small organic molecules have a key enhancing effect on interfacial hydrogen bond regulation and structural stability.

[0039] Electrochemical impedance spectroscopy results further indicate that Example 2 exhibits the highest impedance modulus in the low-frequency region, reaching 1.1 × 10⁻⁶. 6 The impedance value of Ω·cm² indicates that its protective film has the best density and the largest resistance to interfacial charge transfer, while the impedance value of the comparative sample is significantly lower, indicating that its interfacial shielding ability is insufficient.

[0040] The adhesion and migration test results also verified the importance of the synergistic structure. In Example 2, the adhesion reached level 0 and the migration rate was the lowest, at only 1.9%, showing that the oil film still has good interfacial stability under high temperature conditions. The migration rate of the comparative sample increased significantly and the film adhesion level decreased, indicating that a single structure is difficult to suppress component migration.

[0041] In summary, this invention significantly improves the long-term stability and film density of rust-preventive oil under salt spray and humid heat environments by constructing a synergistic system of a dynamic covalent topological entanglement structure of borate ester and a host-guest locked structure of β-cyclodextrin-adamantane, combined with the interfacial regulation effect of L-arginine. All embodiments are superior to the comparative examples, with Example 2 exhibiting the best overall performance, fully demonstrating that this synergistic modification technology route has significant technical effects and structural advantages.

Claims

1. A composite base oil rust inhibitor for ultra-long-lasting salt spray resistance, characterized in that, The composite base oil rust inhibitor comprises the following raw materials in parts by weight: 60-80 parts of synthetic isoalkane base oil; 10-25 parts of ester synthetic base oil; 3-12 parts of borate ester dynamic topological entanglement-host-guest locking synergistic modifier; 0.5-3.0 parts of L-arginine; 2-8 parts of calcium petroleum sulfonate; 1-5 parts of diisooctyl succinate; 1-5 parts of polyisobutylene; 0.1-0.5 parts of antioxidant; and 0.1-0.5 parts of leveling agent. The borate ester dynamic topological entanglement-host-guest locking synergistic modifier is a three-dimensional dynamic protective system formed by constructing a dynamic covalent topological entanglement network through a reversible borate esterification reaction of phenylboronic acid and catechol, and forming a molecular locking structure through host-guest inclusion interaction between β-cyclodextrin and adamantaneamine.

2. The composite base oil rust inhibitor for ultra-long-lasting salt spray resistance as described in claim 1, characterized in that, The borate ester dynamic topological entanglement-host-guest locking synergistic modification material comprises the following raw materials in parts by weight: 1-5 parts of phenylboronic acid; 1-6 parts of catechol; 1-8 parts of β-cyclodextrin; and 0.5-4 parts of adamantane.

3. The composite base oil rust inhibitor for ultra-long-lasting salt spray resistance as described in claim 1 or 2, characterized in that, The preparation method of the borate ester dynamic topological entanglement-host-guest locking synergistic modified material includes the following steps: (1) Add phenylboronic acid and catechol to an organic solvent and react under stirring to obtain a borate ester dynamic network precursor solution; (2) β-cyclodextrin was dissolved in a polar solvent, and adamantane was added. The mixture was then subjected to an inclusion complexation reaction under stirring to obtain a host-guest locked structure solution. (3) The borate ester dynamic network precursor solution is mixed with the host-guest locked structure solution and a composite reaction is carried out under stirring conditions to obtain the borate ester dynamic topological entanglement-host-guest locked synergistic modified material.

4. The composite base oil rust inhibitor for ultra-long-lasting salt spray resistance as described in claim 3, characterized in that, The reaction conditions for step (1) are as follows: in anhydrous ethanol or tetrahydrofuran solvent, the temperature is controlled at 30-70°C, the stirring speed is 300-800 r / min, the reaction time is 1-4 h, and the water content of the system is controlled at 0.1-1.0%.

5. The composite base oil rust inhibitor for ultra-long-lasting salt spray resistance as described in claim 3, characterized in that, The reaction conditions for step (2) are as follows: in a mixed solvent of water and water-alcohol, the temperature is controlled at 25-60℃, the stirring speed is 300-700r / min, the reaction time is 1-6h, and the pH of the system is 6-9.

6. The composite base oil rust inhibitor for ultra-long-lasting salt spray resistance as described in claim 3, characterized in that, The reaction conditions for step (3) are: mixing and reacting at 40-80℃ for 1-5 hours, stirring at 400-900 r / min, and removing the solvent under reduced pressure and drying at 50-90℃ for 2-8 hours after the reaction is completed.

7. The composite base oil rust inhibitor for ultra-long-lasting salt spray resistance as described in claim 1, characterized in that, The antioxidant is a mixture of hindered phenolic antioxidant 1010 and phosphite antioxidant 168 in a mass ratio of 1:0.5 to 1:2; the leveling agent is a mixture of polyether-modified polysiloxane and fluorinated acrylate in a mass ratio of 1:0.2 to 1:

1.

8. A method for preparing a composite base oil rust inhibitor for ultra-long-lasting salt spray resistance, characterized in that, The preparation method includes the following steps: S1, a base oil system is obtained by mixing synthetic isoalkane base oil with ester synthetic base oil; S2, add borate ester dynamic topological entanglement-host-guest locking synergistic modifier to the base oil system for dispersion to obtain the modified base oil system; S3, L-arginine, calcium petroleum sulfonate, diisooctyl succinate, polyisobutylene, antioxidant and leveling agent are added sequentially to the modified base oil system, and the mixture is stirred evenly to obtain the composite base oil rust preventive oil.

9. The preparation method of a composite base oil rust inhibitor for ultra-long-lasting salt spray resistance according to claim 8, characterized in that, The reaction conditions for step S1 are a temperature of 50–80°C, a stirring speed of 300–600 r / min, and a time of 0.5–2 h; the reaction conditions for step S2 are a temperature of 60–90°C, a stirring speed of 600–1200 r / min, and a time of 0.5–2 h.

10. The preparation method of a composite base oil rust inhibitor for ultra-long-lasting salt spray resistance according to claim 8, characterized in that, The reaction conditions for step S3 are: temperature of 60-85℃, stirring speed of 400-800 r / min, and time of 1-3 h. After the reaction is completed, the mixture is filtered and cooled to room temperature.

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