Hydrophobic modifier, its preparation method, and method for preparing modified inorganic filler

Abstract

The present invention relates to the technical field of superhydrophobic material preparation, and provides a hydrophobic modifier, a preparation method thereof, and a method for preparing modified inorganic fillers. The hydrophobic modifier provided by the present invention has a simple and green preparation method, and has the characteristic of self-catalysis during the grafting coupling reaction, without the need to additionally add a catalyst. The hydrophobic modifier provided by the present invention can also be applied to modify inorganic fillers. After the modified inorganic fillers are coated, the water contact angle can reach more than 160°, the rolling angle can reach less than 2°, and it can effectively improve the compatibility between the inorganic fillers and the polymer and improve its dispersibility in the polymer.

Description

Technical Field

[0001] The present invention relates to the technical field of superhydrophobic material preparation, and particularly relates to a hydrophobic modifier, a preparation method thereof, and a method for preparing modified inorganic fillers. Background Art

[0002] Some special effects (such as volume effect, surface effect, etc.) of nanomaterials endow them with many unique physical and chemical properties, such as anti-ultraviolet, anti-aging, enhanced mechanical properties, and improved chemical resistance of materials. Among them, nano-fillers are widely used and have extensive applications in fields such as rubber, plastics, pigments, coatings, and cosmetics. However, due to the large specific surface area of nano-fillers, there are a large number of hydroxyl groups in the surface amorphous layer, high surface energy, and they are very easy to agglomerate. Moreover, unmodified nanoparticles have poor compatibility with polymers, thus affecting the performance of composite materials. To obtain nano-fillers with good compatibility with polymers, various methods have been developed for modifying nanoparticles, such as the coupling agent method, polymer coating method, microcapsule method, etc. Among them, the silane coupling agent method has a simple modification process and significant improvement effect, and is widely used.

[0003] In recent years, as one of the research hotspots, superhydrophobic surfaces have been reported in a large number of relevant theoretical studies and patented technologies. Superhydrophobic coatings have good application prospects in many fields such as self-cleaning, anti-corrosion, and anti-icing of substrates, and their preparation technologies have attracted increasing attention. A large number of studies have shown that the preparation of superhydrophobic surfaces usually needs to start from two aspects: constructing micro-nano rough structures and modifying low-surface-energy substances. Among the reported preparation methods, a mixed coating system composed of a hydrophobic coupling agent, nano-inorganic fillers, a dispersion medium, and a film-forming substance is one of the simple and effective methods for constructing superhydrophobic coatings with low-surface-energy micro-nano structures. Due to environmental protection requirements, using ethanol and water as dispersion media has become the general trend, which requires the coupling agent to have good modification effects on nano-inorganic fillers in the ethanol-water system. Since the hydrophobic coupling agent with a long alkyl chain has low adsorption and grafting reaction efficiency on inorganic fillers in a neutral water-containing environment, many literatures and patents use highly toxic solvents such as toluene and n-hexane as dispersion media to modify inorganic fillers (CN 101249963A). Although this modification method improves the grafting efficiency and utilization rate of the coupling agent, it causes great harm to human health and the environment. Adding a large amount of catalysts such as ammonia water to the water-containing system can promote the grafting reaction of the coupling agent on the inorganic fillers and improve its grafting efficiency (CN 104947169A, CN 105111496A, CN 103305122A), reducing the usage amount of hydrophobic silanes. However, the ammonia removal process is time-consuming and energy-consuming, which is not conducive to environmental protection and energy conservation. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the present invention provides a hydrophobic modifier, which includes a first structural formula, a second structural formula, a third structural formula and a fourth structural formula. The first structural formula is as follows:

[0005]

[0006] The second structural formula is as follows:

[0007]

[0008] The third structural formula is as follows:

[0009]

[0010] The fourth structural formula is as follows:

[0011]

[0012] Wherein, R1 is methoxy or ethoxy;

[0013] R2 is one of methyl, methoxy or ethoxy;

[0014] R3 is one of a hydrophobic alkyl chain, an ether group, an ester group or an alkylphenyl.

[0015] A preparation method of a hydrophobic modifier according to the present invention includes the following steps:

[0016] Put an amino silane coupling agent and an epoxy compound into a solvent, stir, and react at 40-90 °C. After 1-12 h, the hydrophobic modifier is obtained;

[0017] Wherein, the solvent includes at least one of methanol, ether, ethanol, isopropanol, toluene, xylene, ethyl acetate or n-hexane.

[0018] A preparation method of a hydrophobic modifier according to the present invention, the amino silane coupling agent includes at least one of aminopropyltriethoxysilane, aminopropyltrimethoxysilane, 3-(2-aminoethyl)-aminopropyltrimethoxysilane, 3-(2-aminoethyl)-aminopropyltriethoxysilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane or N-aminoethyl-3-aminopropylmethyldiethoxysilane.

[0019] A preparation method of a hydrophobic modifier according to the present invention, the epoxy compound includes at least one of 2-cyclohexyl-2-methylethylene oxide, dodecyl ethylene oxide, phenyl ethylene oxide, dodecyl glycidyl ether, 1,2-epoxyhexadecane, glycidyl neodecanoate or 2-ethylhexyl glycidyl ether.

[0020] The present invention also provides a method for preparing modified inorganic filler based on the hydrophobic modifier, which comprises the following steps:

[0021] S1: Place the inorganic filler in a reactor, add an ethanol aqueous solution to the reactor, and perform ultrasonic dispersion to obtain a first mixed material;

[0022] S2: Drop the hydrophobic modifier into the first mixed material, heat to 40 - 90 °C, and carry out the reaction. After 1 - 12 h, a second mixed material is obtained;

[0023] S3: Wash the second mixed material with an ethanol aqueous solution, perform centrifugation after washing, and obtain the modified inorganic filler after vacuum drying.

[0024] According to the method for preparing modified inorganic filler provided by the present invention, the inorganic filler comprises at least one of nano - silica, nano - aluminum hydroxide, nano - magnesium hydroxide, nano - calcium carbonate, kaolin, nano - titanium dioxide or graphene oxide.

[0025] One or more of the above - mentioned technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0026] 1. The hydrophobic modifier provided by the present invention has low cost and is easy to store. When modifying the inorganic filler, it is not necessary to use highly toxic toluene, n - hexane, etc. for modification. The whole modification process is green and environmentally friendly, the operation is simple, and it is not necessary to add additional catalysts such as acids or alkalis, and a high grafting efficiency can also be achieved, avoiding subsequent reactant treatment work and saving manpower and material resources.

[0027] 2. The hydrophobic modifier provided by the present invention has hydrophilic groups such as amino groups and hydroxyl groups, which can be adsorbed on the surface of inorganic fillers with polar groups such as silica, and also has a basic amino group, which enables the grafting coupling reaction of the modifier to have the characteristics of self - catalysis.

[0028] 3. The hydrophobic modifier provided by the present invention has a bifunctional group (hydrophobic alkyl and amino group), which is beneficial to enhancing the compatibility and interaction between the modified inorganic filler and the film - forming substance (polymer), further realizing the multifunctional application of the modified inorganic filler. Therefore, after coating the inorganic filler modified by the hydrophobic modifier provided by the present invention, the water contact angle can reach more than 160°, and the rolling angle can reach less than 2°.

[0029] 4. The method for preparing modified inorganic filler provided by the present invention uses an ethanol aqueous solution as the dispersion liquid, enabling the preparation of a super - hydrophobic coating with good wear resistance on the substrate of the adhesive.

[0030] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0032] Figure 1 For hydrophobic modifier A1G in Example 1 13 -1 and the infrared spectrogram of modified silica.

[0033] Figure 2 Schematic diagram of the water contact angle of the superhydrophobic particle film scraped with the nanoparticle dispersion in Example 1.

[0034] Figure 3 Morphology diagram of the modified silica prepared in Example 1 after being coated on the surface of the adhesive.

[0035] Figure 4 Infrared spectrograms of different modified inorganic fillers prepared in Examples 3-6. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] To make the objectives, technical solutions and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0037] In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0038] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0039] The present invention provides a hydrophobic modifier, which includes a first structural formula, a second structural formula, a third structural formula, and a fourth structural formula. The first structural formula is shown as follows:

[0040]

[0041] The second structural formula is shown as follows:

[0042]

[0043] The third structural formula is shown as follows:

[0044]

[0045] The fourth structural formula is shown as follows:

[0046]

[0047] Wherein, R1 is methoxy or ethoxy;

[0048] R2 is one of methyl, methoxy, or ethoxy;

[0049] R3 is one of a hydrophobic alkyl chain, an ether group, an ester group, or an alkylphenyl.

[0050] According to a preparation method of the hydrophobic modifier provided by the present invention, it includes the following steps:

[0051] Put an amino silane coupling agent and an epoxy compound into a solvent, stir, and react at 40 - 90 °C. After 1 - 12 h, the hydrophobic modifier is obtained;

[0052] Wherein, the solvent includes at least one of methanol, ether, ethanol, isopropanol, toluene, xylene, ethyl acetate, or n - hexane.

[0053] A preparation method of a hydrophobic modifier provided by the present invention, wherein the amino silane coupling agent includes at least one of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethyl)-aminopropyltrimethoxysilane, 3-(2-aminoethyl)-aminopropyltriethoxysilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane or N-aminoethyl-3-aminopropylmethyldiethoxysilane.

[0054] A preparation method of a hydrophobic modifier provided by the present invention, wherein the epoxy compound includes at least one of 2-cyclohexyl-2-methylethylene oxide, dodecyl ethylene oxide, phenyl ethylene oxide, dodecyl glycidyl ether, 1,2-epoxyhexadecane, glycidyl neodecanoate or 2-ethylhexyl glycidyl ether.

[0055] In one embodiment, the amino silane coupling agent is labeled as A, and the epoxy compound is labeled as G; at room temperature, the epoxy compound G and the amino silane coupling agent A are mixed evenly, and the feeding ratio of the amino silane coupling agent A to the epoxy compound G is 1:1 to 1:2, which are respectively labeled as AG-1, AG-1.5, AG-2, etc. according to different ratios.

[0056] The specific implementation ingredients of the hydrophobic modifier are shown in Table 1.

[0057] Table 1 Specific ingredient composition of two components of the hydrophobic modifier

[0058]

[0059]

[0060] For the hydrophobic modifier prepared according to the ingredient components in Table 1, 4.42 g of 3-aminopropyltriethoxysilane and 4.56 g of glycidyl neodecanoate are placed in diethyl ether, and under the protection of argon, a water bath heating reaction is carried out at 80 °C for 12 h. During the reaction process, 1 1H NMR is used to monitor the reaction degree of the epoxy group; further, molecular sieve is added, then diethyl ether is distilled off, and after being fully dried in a vacuum oven (25 °C), the obtained hydrophobic modifier is:

[0061] It is labeled as A1G 13 -1.

[0062] For the hydrophobic modifier prepared according to the ingredient components in Table 1, 5.29 g of 3-(2-aminoethyl)-aminopropyltriethoxysilane and 7.22 g of 1,2-epoxyhexadecane are placed in isopropanol, and under the protection of argon, a water bath heating reaction is carried out at 80 °C for 10 h. During the reaction process, 1The reaction degree of epoxy groups was monitored by \(^1H\) NMR; further, molecular sieve was added, and then isopropanol was distilled off. After being fully dried in a vacuum oven (25 °C), the hydrophobic modifier obtained was:

[0063] It was labeled as A3G 12 -1.

[0064] For the hydrophobic modifier prepared according to the ingredients in Table 1, 3.59 g of aminopropyltrimethoxysilane and 8.49 g of dodecyl ethylene oxide were placed in ethyl acetate. Under argon protection, the reaction was carried out in a water bath at 80 °C for 8 h. During the reaction, the reaction degree of epoxy groups was monitored by 1 \(^1H\) NMR; further, molecular sieve was added, and then ethyl acetate was distilled off. After being fully dried in a vacuum oven (25 °C), the hydrophobic modifier obtained was:

[0065] It was labeled as A2G8-2.

[0066] For the hydrophobic modifier prepared according to the ingredients in Table 1, 4.69 g of N-aminoethyl-3-aminopropylmethyldiethoxysilane and 2.80 g of 2-cyclohexyl-2-methylethylene oxide were placed in ethyl acetate and methanol. Under argon protection, the reaction was carried out in a water bath at 80 °C for 12 h. During the reaction, the reaction degree of epoxy groups was monitored by 1 \(^1H\) NMR; further, molecular sieve was added, and then ethyl acetate and methanol were distilled off. After being fully dried in a vacuum oven (25 °C), the hydrophobic modifier obtained was:

[0067] It was labeled as A5G7-1.

[0068] For the hydrophobic modifier prepared according to the ingredients in Table 1, 4.45 g of 3-(2-aminoethyl)aminopropyltrimethoxysilane and 7.28 g of dodecyl glycidyl ether were placed in n-hexane and ethyl acetate. Under argon protection, the reaction was carried out in a water bath at 80 °C for 7 h. During the reaction, the reaction degree of epoxy groups was monitored by 1 \(^1H\) NMR; further, molecular sieve was added, and then n-hexane and ethyl acetate were distilled off. After being fully dried in a vacuum oven (25 °C), the hydrophobic modifier obtained was:

[0069] It was labeled as A4G 10 -1.

[0070] The hydrophobic modifier prepared according to the ingredients in Table 1. 5.29 g of 3-(2-aminoethyl)-aminopropyltriethoxysilane and 7.45 g of 2-ethyl-hexyl glycidyl ether were placed in methanol, and under the protection of argon, a water bath heating reaction was carried out at 80 °C for 11 h. During the reaction, 1 the reaction degree of the epoxy group was monitored by

[0071] H NMR; Further, molecular sieve was added, and then methanol was distilled off. After being fully dried in a vacuum oven (25 °C), the obtained hydrophobic modifier was: 14 -2.

[0072] It should be further explained that when the amino-silane coupling agent A and the epoxy compound G are used to prepare the hydrophobic modifier, due to the characteristics of its own structure, the prepared hydrophobic modifier has basic functional groups, so it will make the hydrophobic modifier generate basic amino groups.

[0073] The present invention also provides a method for preparing a modified inorganic filler based on the hydrophobic modifier, including the following steps:

[0074] S1: Place the inorganic filler in a reactor, add an ethanol aqueous solution to the reactor, and perform ultrasonic dispersion to obtain a first mixed material;

[0075] S2: Drop the hydrophobic modifier into the first mixed material, heat to 40-90 °C, and carry out a reaction. After 1-12 h, a second mixed material is obtained;

[0076] S3: Wash the second mixed material with an ethanol aqueous solution, centrifuge after washing, and obtain the modified inorganic filler after vacuum drying.

[0077] Among them, the reactor is a reactor with mechanical stirring.

[0078] Among them, the ethanol aqueous solution in step S1 acts as a dispersion medium. Compared with the existing VOC solvents such as toluene and xylene, it is more environmentally friendly, does not require additional treatment work, and saves manpower and material resources.

[0079] In view of the fact that the coupling reaction of silane is characterized by acceleration under acid or base catalysis, in order to accelerate the reaction and improve the coupling treatment efficiency, it is usually necessary to additionally add an acid or base catalyst, such as ammonia water, etc. in the reaction system. This will undoubtedly increase the additional difficulty in the subsequent treatment of reactants. In step S2, at 40-90 °C, hydrophilic groups such as amino and hydroxyl groups of the hydrophobic modifier are adsorbed on the surface of the inorganic filler. At the same time, the basic amino group of the hydrophobic modifier makes the grafting coupling reaction of the modifier have the characteristics of self-catalysis, and it is not necessary to additionally add ammonia water, etc. as a catalyst to accelerate the reaction and improve the coupling treatment efficiency. It also avoids the subsequent treatment work of removing ammonia and other reactants, and even achieves a relatively high grafting efficiency, as shown in Table 2:

[0080] Table 2 Comparison table of grafting rates of existing hydrophobic modifiers and modified nano-silica of the present invention

[0081]

[0082] As shown in Table 2, among them, Comparative Example 1 is an existing commercial hydrophobic modifier. After modifying nano-silica, the grafting rate can only reach 2.0%; Comparative Example 2 is an existing hydrophobic modifier by adding ammonia water as a catalyst to improve the coupling efficiency. After modifying nano-silica, the grafting rate can reach 8.5%; after the hydrophobic modifier prepared by the present invention modifies nano-silica, the grafting rate can reach 9.6%, which is significantly higher than that of Comparative Example 1 and Comparative Example 2.

[0083] Furthermore, the second mixed material is a nano-particle dispersion liquid.

[0084] Furthermore, the ethanol aqueous solution in step S3 can wash away the unreacted modifier remaining on the second mixed material.

[0085] According to a method for preparing a modified inorganic filler provided by the present invention, the inorganic filler includes at least one of nano-silica, nano-aluminum hydroxide, nano-magnesium hydroxide, nano-calcium carbonate, kaolin, nano-titanium dioxide or graphene oxide.

[0086] Next, according to Examples 1-6, performance tests are carried out on the inorganic filler modified by a method for modifying an inorganic filler provided by the present invention:

[0087] It should be noted that the same method is used in Examples 1-6 to measure the water contact angle and the rolling angle. Furthermore, the hydrophobicity of inorganic nanoparticles can be measured by the water contact angle and the rolling angle. The larger the contact angle and the smaller the rolling angle, the better the hydrophobicity.

[0088] Example 1:

[0089] Weigh 2 g of hydrophilic fumed silica (particle size 7 - 40 nm) and 40 g of ethanol aqueous solution (mass ratio of ethanol to water is 9:1), place them in a 250 ml three-necked flask, carry out mechanical stirring for 2 min and ultrasonic treatment for 10 min to make them evenly dispersed, and add 0.60 g of modifier A1G dropwise under mechanical stirring at 300 r / min. 13 -1. At 60 °C, react under water bath heating for 3 h to obtain a nanoparticle dispersion. Wash the nanoparticle dispersion with ethanol aqueous solution, then carry out centrifugation, and finally obtain modified silica after vacuum drying.

[0090] Among them, scrape the nanoparticle dispersion into a film and measure its contact angle to be 161° and the rolling angle to be 1.7°.

[0091] Figure 1 This is the infrared spectrum of the hydrophobic modifier and modified silica in Example 1. From top to bottom, the first line represents A1G 13 -1, the second line represents the silica nanoparticles, and the third line represents the hydrophobic modified silica. It can be seen that stretching vibration peaks of methyl and methylene groups (2966 cm Figure 1 , 2941 cm -1 , 2881 cm -1 ) and the C=O stretching vibration peak of the ester group (1728 cm -1 ) appear in the modified silica, indicating that the hydrophobic coupling agent component in modifier A1G -1 -1 has been successfully grafted onto the surface of the nano-silica. 13 -1 has been successfully grafted onto the surface of the nano-silica.

[0092] As Figure 2 shown, it is the measured image of the water contact angle of the superhydrophobic particle film scraped from the nanoparticle dispersion obtained in Example 1.

[0093] Furthermore, coat the prepared modified silica on the surface of a substrate containing an adhesive. As Figure 3 shown, it can be seen that the micro-nano structure formed by the spreading of the modified nanoparticles on the surface is uniform and dense, indicating that a superhydrophobic coating with good wear resistance has been prepared.

[0094] Example 2

[0095] Weigh 2 g of hydrophilic fumed silica (particle size 7 - 40 nm) and 60 g of ethanol aqueous solution (mass ratio of ethanol to water is 7:3), place them in a 250 ml three-necked flask, carry out mechanical stirring for 2 min and ultrasonic treatment for 30 min to make them evenly dispersed, and add 1 g of modifier A3G dropwise under mechanical stirring at 500 r / min. 12-1. At 80 °C, react under water bath heating for 3 h to obtain a nanoparticle dispersion. Wash the nanoparticle dispersion with an ethanol aqueous solution, then centrifuge, and finally obtain modified silica after vacuum drying.

[0096] Among them, scrape the nanoparticle dispersion into a film and measure its contact angle to be 162° and the rolling angle to be 1.8°.

[0097] Example 3

[0098] Weigh 2 g of hydrophilic fumed silica (particle size 50 nm) and 40 g of an ethanol aqueous solution (mass ratio of ethanol to water is 9:1) and place them in a 250 ml three-necked flask. Carry out mechanical stirring for 2 min and ultrasonic treatment for 10 min to make it disperse evenly. Under mechanical stirring at 300 r / min, add 1 g of modifier A2G8-2 dropwise. At 60 °C, react under water bath heating for 1 h to obtain a nanoparticle dispersion. Wash the nanoparticle dispersion with an ethanol aqueous solution, then centrifuge, and finally obtain modified silica after vacuum drying.

[0099] Among them, scrape the nanoparticle dispersion into a film and measure its contact angle to be 159° and the rolling angle to be 2.6°.

[0100] Examples 1-3 are all for modifying fumed nano-silica. Among them, the contact angle of the modified silica prepared in Example 2 is 162° and the rolling angle is 1.8°. The contact angle of the modified silica prepared in Example 1 is 161° and the rolling angle is 1.7°. The contact angle of the modified silica prepared in Example 3 is 159° and the rolling angle is 2.6°. The hydrophobicity of Example 1 and Example 2 is better than that of Example 3. Therefore, compare the performance of the modified silica prepared in Example 3 with that of Comparative Example 1 and Comparative Example 2 in the prior art, as shown in Table 3:

[0101] Table 3 Performance comparison of the modified silica prepared in Example 3 and the prior art

[0102]

[0103]

[0104] As shown in Table 3, Comparative Example 1 is an existing commercial hydrophobic modifier. After modifying nano-silica, it cannot form a hydrophobic film, is hydrophilic, and the rolling angle is greater than 90°. Comparative Example 2 is an existing hydrophobic modifier with ammonia water added as a catalyst to improve the coupling efficiency. After modifying nano-silica, the contact angle is 155° and the rolling angle is 2.92°. After modifying nano-silica with the hydrophobic modifier prepared in the present invention, the contact angle is 159° and the rolling angle is 2.6°. According to the fact that the larger the contact angle and the smaller the rolling angle, the better the hydrophobicity, it can be seen that the hydrophobicity of the modified silica prepared in Example 3 is significantly better than that of Comparative Example 1 and Comparative Example 2.

[0105] Furthermore, the hydrophobic properties of Example 1 and Example 2 are also better than those of Comparative Example 1 and Comparative Example 2.

[0106] Example 4

[0107] Weigh 2 g of hydrophilic aluminum hydroxide (particle size of 50 nm) and 40 g of ethanol aqueous solution (mass ratio of ethanol to water is 9:1) and place them in a 250 ml three-necked flask. Carry out mechanical stirring for 2 min and ultrasonic treatment for 30 min to make them evenly dispersed. Under mechanical stirring at 300 r / min, add 1.5 g of modifier A5G7-1 dropwise. React under water bath heating at 60 °C for 3 h to obtain a nano-particle dispersion. Wash the nano-particle dispersion with ethanol aqueous solution, then carry out centrifugation, and finally obtain modified aluminum hydroxide after vacuum drying.

[0108] Among them, scrape the nano-particle dispersion into a film and test its contact angle to be 156° and the rolling angle to be 3°.

[0109] Example 5

[0110] Weigh 2 g of kaolin (1000 mesh) and 40 g of ethanol aqueous solution (mass ratio of ethanol to water is 9:1) and place them in a 250 ml three-necked flask. Carry out mechanical stirring for 2 min and ultrasonic treatment for 10 min to make them evenly dispersed. Under mechanical stirring at 300 r / min, add 0.6 g of modifier A4G 10 -1. React under water bath heating at 60 °C for 3 h to obtain a nano-particle dispersion. Wash the nano-particle dispersion with ethanol aqueous solution, then carry out centrifugation, and finally obtain modified kaolin after vacuum drying.

[0111] Among them, scrape the nano-particle dispersion into a film and test its contact angle to be 146° and the rolling angle to be 15°.

[0112] Example 6

[0113] Weigh 4 g of graphene oxide and 100 g of ethanol aqueous solution (the mass ratio of ethanol to water is 9:1) and place them in a 250 ml three-necked flask. Carry out mechanical stirring for 2 min and ultrasonic treatment for 30 min to make them evenly dispersed. While stirring mechanically at 300 r / min, add 0.2 g of modifier A3G 14 -2. At 60 °C, react under water bath heating for 5 h to obtain a nanoparticle dispersion. Wash the nanoparticle dispersion with ethanol aqueous solution, then carry out centrifugation, and finally obtain modified graphene after vacuum drying.

[0114] Among them, the nanoparticle dispersion is scraped into a film, and its contact angle is measured to be 145° and the rolling angle is 20°.

[0115] According to Examples 3-6, different inorganic fillers are modified respectively, such as Figure 4 shown. From top to bottom, the first line represents the modified kaolin prepared in Example 5, the second line represents the modified silica prepared in Example 3, the third line represents the modified graphene prepared in Example 6, and the fourth line represents the modified aluminum hydroxide prepared in Example 4. From Figure 4 it can be clearly seen the appearance of the stretching vibration peaks of methyl and methylene (2966 cm -1 , 2941 cm -1 , 2881 cm -1 ) and the C=O stretching vibration peak of the ester group (1728 cm -1 ), indicating that the hydrophobic modifier has been successfully grafted onto the surface of the inorganic material. This is because the hydrophobic modifier prepared in the present invention has bifunctional groups (hydrophobic alkyl and amino), which is beneficial to enhancing the compatibility and interaction between the modified inorganic filler and the film-forming substance (polymer). Therefore, after coating the inorganic filler modified with the hydrophobic modifier of the present invention technology, its water contact angle can reach more than 160° and the rolling angle can reach below 2°.

[0116] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing examples, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing examples, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various examples of the present invention.

Claims

1. A hydrophobic modifier, characterized in that, It includes a first structural formula, a second structural formula, a third structural formula and a fourth structural formula. The first structural formula is as follows: ； The second structural formula is as follows: ； ； ； The third structural formula is as follows: ； The fourth structural formula is as follows: 。 2. A method for preparing the hydrophobic modifier according to claim 1, characterized in that, It includes the following steps: Put an amino silane coupling agent and an epoxy compound in a solvent, stir, and react at 40~90°C. After 1~12 h, the hydrophobic modifier is obtained; Among them, the solvent includes at least one of methanol, ether, ethanol, isopropanol, toluene, xylene, ethyl acetate or n-hexane.

3. The preparation method of the hydrophobic modifier according to claim 2, characterized in that, The amino silane coupling agent includes at least one of aminopropyltriethoxysilane, aminopropyltrimethoxysilane, 3-(2-aminoethyl)-aminopropyltrimethoxysilane, 3-(2-aminoethyl)-aminopropyltriethoxysilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane or N-aminoethyl-3-aminopropylmethyldiethoxysilane.

4. The preparation method of the hydrophobic modifier according to claim 2, characterized in that, The epoxy compound includes at least one of 2-cyclohexyl-2-methylethylene oxide, dodecyl ethylene oxide, phenyl ethylene oxide, dodecyl glycidyl ether, 1,2-epoxyhexadecane, glycidyl neodecanoate or 2-ethylhexyl glycidyl ether.

5. A method for preparing a modified inorganic filler using the hydrophobic modifier according to claim 1, characterized in that, It includes the following steps: S1: Put the inorganic filler in a reactor, add an ethanol aqueous solution to the reactor, and perform ultrasonic dispersion to obtain a first mixed material; S2: Drop the hydrophobic modifier into the first mixed material, heat to 40~90°C, and react. After 1~12 h, a second mixed material is obtained; S3: Wash the second mixed material with an ethanol aqueous solution, centrifuge after washing, and obtain the modified inorganic filler after vacuum drying.

6. The method for modifying inorganic filler according to claim 5, characterized in that, The inorganic filler includes at least one of nano-silica, nano-aluminum hydroxide, nano-magnesium hydroxide, nano-calcium carbonate, kaolin, nano-titanium dioxide or graphene oxide.

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