Self-cleaning anticorrosive material and preparation method thereof

Abstract

The invention relates to a self-cleaning anticorrosive material and a preparation method thereof, and belongs to the technical field of anticorrosive materials. The preparation method comprises the following steps: preparing a self-made modifier, modifying high-density polyethylene through the modifier to obtain modified high-density polyethylene, and blending the modified high-density polyethylene with polydimethylsiloxane and fumed silica to obtain the self-cleaning anticorrosive material. Nano silicon dioxide particles can be fixed on the surface of high-density polyethylene through silicon-oxygen-silicon covalent bonds and are similar to the main chain structure of polydimethylsiloxane, so that the three phases have good interfacial compatibility, and the polydimethylsiloxane has excellent chemical inertness and hydrophobicity, so that the surface of the high-density polyethylene is protected. After being blended with polyethylene, the material has good hydrophobicity, so that the self-cleaning anti-corrosion characteristic is realized.

Description

Technical Field

[0001] This invention belongs to the field of anti-corrosion materials technology, specifically, it relates to a self-cleaning anti-corrosion material and its preparation method. Background Technology

[0002] Traditional corrosion protection technologies mainly rely on coatings and metal plating. However, coatings require frequent maintenance and recoating, and damage to metal plating can lead to galvanic corrosion, accelerating substrate corrosion. Therefore, developing a new type of corrosion-resistant material that is long-lasting, environmentally friendly, and combines active protection with self-cleaning functions has become an urgent need for industry and academia. High-density polyethylene (HDPE), as a general-purpose plastic, is considered an ideal anti-corrosion material due to its excellent chemical stability and extremely low permeability. However, pure HDPE has certain limitations; its low surface energy is insufficient for self-cleaning, thus requiring modification to improve its overall performance. Polydimethylsiloxane (PDS) possesses low surface energy and good mechanical properties. The extremely low surface energy and potential hydrophobic properties of PDS can be imparted to the surface of composite materials, thereby enabling the material to acquire self-cleaning functionality while maintaining the excellent anti-corrosion properties of HDPE. However, their compatibility differs significantly, and direct blending can easily lead to macroscopic phase separation and interfacial defects. This can cause microscopic pores or stress concentration points within the material, severely affecting its mechanical and hydrophobic properties.

[0003] Based on this, the present invention provides a self-cleaning anti-corrosion material and its preparation method. Summary of the Invention

[0004] The purpose of this invention is to provide a self-cleaning anti-corrosion material and its preparation method, so as to solve the problems mentioned in the background art.

[0005] The objective of this invention can be achieved through the following technical solutions: A method for preparing a self-cleaning anti-corrosion material includes the following steps: Step 1: Add aminoolefin, silane coupling agent, potassium iodide and toluene to a three-necked flask, attach a condenser and thermometer, turn on magnetic stirring, and react at room temperature for 2-3 hours. After the reaction is complete, cool to room temperature and filter to remove the solid. Remove the solvent from the remaining filtrate by rotary evaporation, extract with ethyl acetate and retain the organic phase. Wash the organic phase with water and dry to obtain the modifier precursor. The second step involves adding the modifier precursor, dialkyl phosphite, iodine, and toluene into a three-necked flask, attaching a condenser and a thermometer, turning on the magnetic stirrer, and reacting at 30–40°C for 30–40 minutes. After the reaction is complete and cooled to room temperature, the solvent is removed by rotary evaporation, and the organic phase is extracted with ethyl acetate and retained. The organic phase is then washed with saturated brine and dried to obtain the modifier. The third step involves mixing high-density polyethylene and the modifier in a torque rheometer, irradiating the sample at room temperature, and then extracting the sample with acetone solution and drying it to obtain modified high-density polyethylene. Step 4: After uniformly mixing modified high-density polyethylene, polydimethylsiloxane, fumed silica, antioxidant and lubricant, the mixture is transferred to a screw extruder for melt extrusion, and then cooled and granulated to obtain a self-cleaning anti-corrosion material.

[0006] Furthermore, the general structural formula of the aminoolefin in the first step is: Where n is a natural number greater than 2 and less than 6.

[0007] Furthermore, the silane coupling agent in the first step is at least one of silane coupling agent KH-430 and silane coupling agent A-143.

[0008] Furthermore, in the first step, the mass ratio of aminoolefin, silane coupling agent, potassium iodide and toluene is 8.4–14.4: 24–28: 16–18: 200–240.

[0009] Furthermore, the dialkyl phosphite in the second step is one of dimethyl phosphite and diethyl phosphite.

[0010] Furthermore, in the second step, the mass ratio of the modifier precursor, dialkyl phosphite, iodine, and toluene is 26.5–28.5: 11–13: 0.2–0.4: 160–180.

[0011] Furthermore, in the third step, the mass ratio of high-density polyethylene to modifier is 50–60:34–39.

[0012] Furthermore, the lubricant in the fourth step is at least one of high-density polyethylene wax and oxidized high-density polyethylene wax.

[0013] Furthermore, the antioxidant in the fourth step is at least one of antioxidant 1010, antioxidant 1076, and antioxidant 168.

[0014] Furthermore, in the fourth step, the mass ratio of modified high-density polyethylene, polydimethylsiloxane, fumed silica, antioxidant, and lubricant is 50–60: 40–50: 20–25: 1–3: 1–3.

[0015] Furthermore, the temperature of melt extrusion in the fourth step is 160–180°C.

[0016] A self-cleaning anti-corrosion material is prepared by any of the above preparation steps.

[0017] The beneficial effects of this invention are: This invention uses an aminoolefin and a silane coupling agent to carry out a nucleophilic substitution reaction to obtain a modifier precursor. The modifier precursor and dialkyl phosphite are used as raw materials to carry out a nucleophilic substitution reaction to obtain a modifier. High-density polyethylene is then irradiated and grafted with the modifier to obtain modified high-density polyethylene. Finally, the modified high-density polyethylene, polydimethylsiloxane and fumed silica are blended and melt-extruded to obtain a self-cleaning anti-corrosion material.

[0018] The polydimethylsiloxane of this invention possesses excellent chemical inertness and hydrophobicity. When blended with high-density polyethylene, it forms a homogeneous system, resulting in a composite material with extremely low and very stable surface energy. Simultaneously, nano-silica particles are uniformly and firmly dispersed within the modified high-density polyethylene and polydimethylsiloxane matrix, playing a crucial role in reinforcement and filling, and constructing a robust three-phase interface. This forms a hydrophobic and anti-corrosion barrier, effectively blocking the penetration of water, oxygen, and corrosive media. This gives the material excellent hydrophobic properties, increasing the water contact angle and allowing water droplets to easily roll off. As the droplets roll, they carry away surface dust and contaminants, achieving self-cleaning and thus providing the material with a self-cleaning and anti-corrosion effect.

[0019] This invention loads a siloxane structure onto the surface of modified high-density polyethylene (HDPE). During blending, this structure combines with the hydroxyl groups on the surface of fumed silica to form a robust silicon-oxygen-silicon structure. This improves the dispersibility of the filler in the blend system while covalently fixing nano-silica particles to the HDPE surface. The silane portion on the modified HDPE has a similar main chain structure to polydimethylsiloxane (PDMS), resulting in good compatibility. The PDMS molecular chains can easily wrap around the silane molecular network grafted onto the HDPE surface, forming an interpenetrating interface and ensuring good interfacial compatibility among the three phases. Therefore, under stress, stress can be effectively transferred from the flexible PDMS to the rigid fumed silica reinforcing filler, and then to the HDPE skeleton, achieving efficient reinforcement and significantly improving the material's wear resistance.

[0020] The phosphate ester structure in the modifier of this invention can cause dehydration and carbonization of the material surface during combustion, forming a dense char protective layer. Simultaneously, the silicon element in the material forms a ceramic protective layer on the material surface during combustion. This synergistic effect of phosphorus catalyzing char formation and silicon enhancing the stability and density of the char layer effectively isolates oxygen, enabling the material to achieve a flame-retardant and protective effect. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments in this application specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection claimed in this application.

[0022] The raw materials used in this invention are not particularly restricted in terms of their source; they can be purchased from the market or prepared using conventional methods known to those skilled in the art.

[0023] Example 1

[0024] A method for preparing a self-cleaning anti-corrosion material includes the following steps: Step 1: Add 8.4g of 5-amino-1-pentene, 24g of silane coupling agent KH-430, 16g of potassium iodide and 200g of toluene to a three-necked flask, attach a condenser and thermometer, turn on magnetic stirring, and react at room temperature for 3 hours. After the reaction is complete, cool to room temperature and filter to remove the solid. Remove the solvent from the remaining filtrate by rotary evaporation, extract with ethyl acetate and retain the organic phase. Wash the organic phase with water and dry to obtain the modifier precursor. Step 2: Add 26.5g of modifier precursor, 11g of dimethyl phosphite, 0.2g of iodine and 160g of toluene to a three-necked flask, attach a condenser and thermometer, turn on magnetic stirring, and react at 30℃ for 40min. After the reaction is completed and cooled to room temperature, remove the solvent by rotary evaporation, extract with ethyl acetate and retain the organic phase, then wash the organic phase with saturated brine and dry to obtain the modifier. The third step involves adding 50g of high-density polyethylene and 34g of modifier to a torque rheometer and mixing them evenly. The mixture is then subjected to irradiation grafting at room temperature. After irradiation, the irradiated sample is placed in a Soxhlet extraction device and extracted with acetone solution for 48 hours before drying to obtain modified high-density polyethylene. Step 4: Mix 50g of modified high-density polyethylene, 50g of polydimethylsiloxane, 25g of fumed silica, 1g of high-density polyethylene wax and antioxidant 1010 evenly, transfer the mixture to a screw extruder and melt-extrude it at 160°C, and then cool and granulate it to obtain a self-cleaning anti-corrosion material.

[0025] A self-cleaning anti-corrosion material is prepared by the above preparation steps.

[0026] Example 2

[0027] A method for preparing a self-cleaning anti-corrosion material includes the following steps: Step 1: Add 11.4 g of 7-amino-1-heptenene, 26 g of silane coupling agent A-143, 17 g of potassium iodide and 220 g of toluene to a three-necked flask, attach a condenser and thermometer, turn on magnetic stirring, and react at room temperature for 2.5 h. After the reaction is complete, cool to room temperature and filter to remove the solid. Remove the solvent from the remaining filtrate by rotary evaporation, extract with ethyl acetate and retain the organic phase. Wash the organic phase with water and dry to obtain the modifier precursor. Step 2: Add 27.5g of modifier precursor, 12g of dimethyl phosphite, 0.3g of iodine and 170g of toluene to a three-necked flask, attach a condenser and thermometer, turn on magnetic stirring, and react at 35℃ for 35min. After the reaction is completed and cooled to room temperature, remove the solvent by rotary evaporation, extract with ethyl acetate and retain the organic phase, then wash the organic phase with saturated brine and dry to obtain the modifier. The third step involves adding 55g of high-density polyethylene and 36.5g of modifier to a torque rheometer and mixing them evenly. The mixture is then subjected to irradiation grafting at room temperature. After irradiation, the irradiated sample is placed in a Soxhlet extraction device and extracted with acetone solution for 44 hours before drying to obtain modified high-density polyethylene. Step 4: Mix 55g of modified high-density polyethylene, 45g of polydimethylsiloxane, 22.5g of fumed silica, 2g of oxidized high-density polyethylene wax and 2g of antioxidant 1076 evenly, transfer the mixture to a screw extruder and melt extrude at 170℃, and then cool and granulate to obtain a self-cleaning anti-corrosion material.

[0028] A self-cleaning anti-corrosion material is prepared by the above preparation steps.

[0029] Example 3

[0030] A method for preparing a self-cleaning anti-corrosion material includes the following steps: Step 1: Add 14.4g of 9-amino-1-nonene, 28g of silane coupling agent KH-430, 18g of potassium iodide and 240g of toluene to a three-necked flask, attach a condenser and thermometer, turn on magnetic stirring, and react at room temperature for 2 hours. After the reaction is complete, cool to room temperature and filter to remove the solid. Remove the solvent from the remaining filtrate by rotary evaporation, extract with ethyl acetate and retain the organic phase. Wash the organic phase with water and dry to obtain the modifier precursor. Step 2: Add 28.5g of modifier precursor, 13g of dimethyl phosphite, 0.4g of iodine and 180g of toluene to a three-necked flask, attach a condenser and thermometer, turn on magnetic stirring, and react at 40℃ for 30min. After the reaction is completed and cooled to room temperature, remove the solvent by rotary evaporation, extract with ethyl acetate and retain the organic phase, then wash the organic phase with saturated brine and dry to obtain the modifier. The third step involves adding 60g of high-density polyethylene and 39g of modifier to a torque rheometer and mixing them evenly. The mixture is then subjected to irradiation grafting at room temperature. After irradiation, the irradiated sample is placed in a Soxhlet extraction device and extracted with acetone solution for 40 hours before drying to obtain modified high-density polyethylene. Step 4: Mix 60g of modified high-density polyethylene, 40g of polydimethylsiloxane, 20g of fumed silica, 3g of high-density polyethylene wax and 3g of antioxidant 168 evenly, transfer the mixture to a screw extruder and melt-extrude at 180°C, and then cool and granulate to obtain a self-cleaning anti-corrosion material.

[0031] A self-cleaning anti-corrosion material is prepared by the above preparation steps.

[0032] Comparative Example 1 The difference between this comparative example and Example 2 is that the high-density polyethylene is not modified, while the other raw materials and preparation steps remain unchanged.

[0033] Experimental Example 1 The materials in Examples 1-3 and Comparative Example 1 were subjected to performance tests. The surface water contact angle of each group of materials was tested according to GB / T30693-2014 "Measurement of Water Contact Angle of Plastic Films". The mass wear of each group of materials after 4000 cycles of friction was tested according to GB / T3680-2005 "Determination of Abrasion Resistance of Plastic Products". The flame retardancy rating of each group of materials was tested according to GB / T2408-2021 "Determination of Combustion Performance of Plastics". The test results are shown in Table 1.

[0034] Table 1

[0035] Table 1 shows that, compared with Comparative Example 1, Examples 1-3 have higher surface water contact angles and flame retardant ratings, and lower mass wear, indicating that the hydrophobicity, wear resistance and flame retardancy of Examples 1-3 are better than those of Comparative Example 1. Combined with Comparative Example 1, it can be seen that the modification of high-density polyethylene can effectively improve the hydrophobicity, wear resistance and flame retardancy of the material.

[0036] The descriptions of the above embodiments are merely illustrative of the methods and core ideas of the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a self-cleaning anti-corrosion material, characterized in that, Includes the following steps: Preparation of modified high-density polyethylene: A modifier precursor is obtained by nucleophilic substitution reaction of aminoolefin and silane coupling agent, and then a modifier is obtained by nucleophilic substitution reaction of modifier precursor and dialkyl phosphite. The modified high-density polyethylene is then subjected to irradiation graft modification by the modifier to obtain modified high-density polyethylene. Self-cleaning anti-corrosion material: Modified high-density polyethylene, polydimethylsiloxane, fumed silica, antioxidant, and lubricant are blended and then melt-extruded to obtain a self-cleaning anti-corrosion material.

2. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, The general structural formula of aminoolefins is Where n is a natural number greater than 2 and less than 6.

3. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, The silane coupling agent is at least one of silane coupling agent KH-430 and silane coupling agent A-143.

4. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, The mass ratio of aminoolefin to silane coupling agent is 8.4–14.4:24–28.

5. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, Dialkyl phosphite is one of dimethyl phosphite and diethyl phosphite.

6. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, The mass ratio of the modifier precursor to dialkyl phosphite is 26.5–28.5:11–13, and the mass ratio of high-density polyethylene to modifier is 50–60:34–39.

7. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, The lubricant is at least one of high-density polyethylene wax and oxidized high-density polyethylene wax, and the antioxidant is at least one of antioxidant 1010, antioxidant 1076, and antioxidant 168.

8. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, The mass ratio of modified high-density polyethylene, polydimethylsiloxane, fumed silica, antioxidant, and lubricant is 50-60:40-50:20-25:1-3:1-3.

9. The method for preparing a self-cleaning anti-corrosion material according to claim 1, characterized in that, The temperature for melt extrusion is 160–180℃.

10. A self-cleaning anti-corrosion material, characterized in that, A self-cleaning anti-corrosion material is prepared by the preparation method described in any one of claims 1 to 9.

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