A wear-resistant type silicone-modified acrylate resin for paint and a preparation process thereof

Abstract

The application relates to the technical field of coatings, and particularly discloses a wear-resistant organic silicon modified acrylate resin for coatings and a preparation process thereof. The preparation process is obtained by supramolecular anchoring and dynamic covalent crosslinking reaction of AD / carboxyl bifunctional nano composite particles and organic silicon modified acrylate resin containing beta-cyclodextrin and hydrazine groups. The application solves the compatibility problem of the organic silicon and the acrylate resin through chemical copolymerization, solves the interface separation and void defects of the nanometer material and the resin caused by the polarity difference through double-mechanism crosslinking, and the prepared organic silicon modified acrylate resin has good wear resistance.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of coatings, in particular to a wear-resistant organic silicon modified acrylate resin for coatings and a preparation process thereof. BACKGROUND

[0002] In the field of coatings, resin as the core of film formation, its performance directly determines the protection and decoration value of the coating, and with the upgrading of the demand for wear resistance of the coating in the downstream industries such as automobiles, electronics and furniture, the traditional resin gradually cannot meet the requirements. Among them, although the acrylate resin is widely used in various coatings for a long time due to its good film forming property, strong adhesion, excellent weather resistance and controllable cost, the structure characteristics of the molecular main chain C-C bond and the polar side chain make it prone to plastic deformation after curing, the surface energy is high and it is easy to adhere to the friction medium, resulting in insufficient wear resistance. The organic silicon resin has excellent wear resistance, weather resistance and low surface energy due to the characteristics of high bond energy of Si-O-Si main chain and non-polar side chain, which can make up for the wear resistance short board of the acrylate resin, but when it is used alone, it has defects such as poor adhesion, weak film forming property and high cost, and cannot be directly used as a coating base material. Based on the complementary performance of the two, the organic silicon modified acrylate resin has become the core path to solve the balance problem of wear resistance, adhesion and cost, and the chemical modification through chemical bond realizes the uniform distribution of the organic silicon chain segment, which takes into account the wear resistance and adhesion, and has become the mainstream technical direction.

[0003] The patent application file with the publication number CN106700874A discloses an environmentally friendly flame-retardant building insulation coating and a preparation method thereof. In the patent application file, the insulation paint prepared by taking polyurethane, organic silicon modified epoxy resin and nano silicon dioxide as main materials has stable quality and good use effect. Due to the addition of nano silicon dioxide, the insulation nano coating not only has the characteristics of conventional insulation coating, but also has the best insulation performance, and also shows better paint film appearance, impact strength and heat resistance. However, due to the difference in polarity between nano silicon dioxide and organic silicon modified epoxy resin, the system is not compatible, the combination of the two is very poor, interface isolation and void defects are formed, and finally the mechanical strength of the coating is reduced. SUMMARY

[0004] In order to improve the wear resistance of the coating, the application provides a wear-resistant organic silicon modified acrylate resin for coatings and a preparation process thereof.

[0005] In the first aspect, the application provides a preparation process of a wear-resistant organic silicon modified acrylate resin for coatings, which adopts the following technical scheme:

[0006] The application discloses a preparation process of a wear-resistant organic silicon modified acrylate resin for paint, and the wear-resistant organic silicon modified acrylate resin is obtained through supramolecular anchoring and dynamic covalent cross-linking reaction of AD / carboxyl bifunctionalized nano composite particles and organic silicon modified acrylate resin containing beta-cyclodextrin and hydrazine groups.

[0007] The AD / carboxyl bifunctionalized nano composite particles are prepared by modifying nanodiamond and graphene oxide with adamantane amine and succinic anhydride.

[0008] The organic silicon modified acrylate resin containing beta-cyclodextrin and hydrazine groups is prepared by copolymerization of organic silicon monomers, acrylate monomers, beta-cyclodextrin acrylate, acrydian and glycidyl methacrylate.

[0009] By adopting the technical scheme, the adamantane groups on the surface of the nano composite particles and the beta-cyclodextrin groups in the molecular chain of the resin are anchored through host-guest recognition; meanwhile, the hydrazine groups in the molecular chain of the resin and the carboxyl groups on the surface of the nano composite particles are cross-linked through acylhydrazone bonds. The super-high hardness of the nanodiamond, the crack blocking effect of the graphene oxide and the high bond energy characteristics of the organic silicon Si-O-Si bond are utilized to break through the shortcoming of the wear resistance of the traditional acrylate resin from the aspects of the reinforcing phase and the matrix, the compatibility problem of the organic silicon and the acrylate resin is solved through chemical copolymerization, the interface separation and the void defects of the nano material and the resin caused by the polarity difference are solved through the double-mechanism cross-linking, and the prepared organic silicon modified acrylate resin has good wear resistance.

[0010] Preferably, the preparation raw materials of the AD / carboxyl bifunctionalized nano composite particles include, in mass parts, nanodiamond 2.5-9 parts, graphene oxide 0.8-3.5 parts, adamantane amine 0.9-2.3 parts, succinic anhydride 0.5-1.6 parts and deionized water 83-95 parts.

[0011] The preparation method of the AD / carboxyl bifunctionalized nano composite particles is as follows: the nanodiamond and the graphene oxide are dispersed in deionized water, ultrasonic treatment is carried out, then the adamantane amine is added, stirring and reaction are carried out, then the succinic anhydride is added for continuous reaction, and finally the AD / carboxyl bifunctionalized nano composite particles are obtained through centrifugation and washing.

[0012] By adopting the above technical solution, the preparation method ensures the bifunctionality and performance stability of the nanocomposite particles by adding adamantane amine first and then succinic anhydride. Specifically, the amino group of adamantane amine needs to preferentially undergo amidation and etherification reactions with the carboxyl and hydroxyl groups on the surface of graphene oxide to fully graft and form the adamantane (Ad) sites required for supramolecular recognition. If succinic anhydride is added first, it will preferentially react with the hydroxyl groups on the surface of graphene oxide and nanodiamonds to introduce carboxyl groups. Subsequently, the amino group of adamantane amine may undergo side reactions with the newly added carboxyl groups and be consumed, resulting in insufficient grafting density of Ad sites and affecting supramolecular anchoring. Effects: By first grafting the Ad group and then adding succinic anhydride, the reaction between the anhydride and the remaining hydroxyl groups on the surface of the nanoparticles can introduce dynamic carboxyl bond sites. This avoids competition for reaction sites between the two functional reagents and ensures that the Ad sites and carboxyl sites are evenly distributed on the particle surface. This ensures that the nanocomposite particles can form stable supramolecular anchoring and dynamic covalent cross-linking with the resin, reducing agglomeration and improving dispersion stability. If the order of addition is reversed or they are added simultaneously, the number of bifunctional sites will be insufficient and the distribution will be uneven, ultimately reducing the interfacial bonding force between the nanoparticles and the resin and failing to exert its wear-resistant enhancement effect.

[0013] Preferably, the raw materials for preparing the AD / carboxyl bifunctionalized nanocomposite particles further include 1-2 parts by weight of natural nanocellulose;

[0014] The preparation method of the AD / carboxyl bifunctional nanocomposite particles is as follows: nanodiamond, graphene oxide and natural nanocellulose are dispersed in deionized water, ultrasonically treated and then adamantane is added. After stirring and reacting, succinic anhydride is added and the reaction is continued. After centrifugation and washing, the AD / carboxyl bifunctional nanocomposite particles are obtained.

[0015] By adopting the above technical solution, introducing an appropriate amount of natural nanocellulose into AD / carboxyl bifunctionalized nanocomposite particles can form a synergistic reinforcing structure of rigid core-lamellae barrier-fiber skeleton. Specifically, natural nanocellulose, with its large aspect ratio, can act as a fiber skeleton to bridge nanodiamonds and graphene oxide, forming a three-dimensional interconnected network, significantly improving the overall crack propagation resistance of the particles and avoiding the problem of easy detachment when single particles are dispersed. Its abundant hydroxyl groups on the surface can also form hydrogen bonds with the carboxyl groups of graphene oxide and the hydroxyl groups of nanodiamonds, enhancing the bonding stability of the three, while also assisting in the uniform grafting of adamantane and succinic anhydride on the particle surface, reducing the aggregation of functional sites. In addition, natural nanocellulose is widely available, inexpensive, and biodegradable, avoiding the environmental residue risks of traditional artificial nanoparticles, which is in line with the trend of green coatings.

[0016] Preferably, the ultrasonic treatment power is 500-600W, the centrifugation speed is 2500-3500rpm, and the centrifugation time is 5-15min.

[0017] Preferably, the monomer raw materials of the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine include the following raw materials in parts by weight: 40-50 parts of methyl methacrylate, 25-32 parts of isooctyl acrylate, 8-12 parts of γ-methacryloyloxypropyltrimethoxysilane, 4-7 parts of β-cyclodextrin acrylate, 5-8 parts of acryloyl hydrazine, and 1-3 parts of glycidyl methacrylate.

[0018] The preparation method of the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine is as follows: the monomer raw material is mixed with an emulsifier, deionized water is added and stirred to form a pre-emulsion, a portion of the pre-emulsion is heated and an initiator is added to react and form a seed emulsion, and the remaining pre-emulsion is added dropwise and kept at the temperature to obtain the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine.

[0019] By adopting the above technical solution, the hardness and flexibility of the resin matrix can be flexibly balanced by controlling the ratio of the hard monomer methyl methacrylate to the soft monomer isooctyl acrylate, thus avoiding plastic deformation or brittleness after curing. γ-Methacryloxypropyltrimethoxysilane can improve wear resistance and weather resistance through Si-O-Si bonds, and solve the compatibility problem between organosilicon and acrylate resin through chemical copolymerization. β-cyclodextrin acrylate, hydrazine acrylate, and glycidyl methacrylate, as functional monomers, respectively ensure the number of molecular anchoring sites, the amount of dynamic acylhydrazone bond formation, and the crosslinking density and adhesion, ultimately resulting in good comprehensive performance.

[0020] Preferably, the monomer raw material of the organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine group further includes 0.5-1 parts by weight of isocyanate monomer.

[0021] By adopting the above technical solution, on the one hand, the double bond of the isocyanate monomer can participate in free radical copolymerization simultaneously with methyl methacrylate, organosilicon monomers, etc., to stably graft the -NCO group onto the resin backbone, avoiding uneven distribution caused by physical mixing; on the other hand, the -NCO group can react with the hydrazine group of acryloyl hydrazine in the resin and the hydroxyl group on the surface of the nanocomposite particles to form dynamic urea bonds, which together with the original acylhydrazone bonds to construct a urea bond-acylhydrazone bond double dynamic crosslinking network. The hydrolysis resistance of the urea bond is better than that of the acylhydrazone bond, which can improve the stability of the dynamic network in a humid environment. At the same time, the two work together to enhance the energy dissipation efficiency of bond breaking and recombination, reducing coating damage during wear.

[0022] Preferably, the monomer raw material of the organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine also includes 0.1-0.5 parts by weight of divinylbenzene.

[0023] By adopting the above technical solution, the two double bonds in the divinylbenzene molecule participate in free radical copolymerization, forming a small number of permanent crosslinking points in the resin network. These permanent crosslinking points can construct a rigid skeleton, effectively enhancing the structural stability and fatigue resistance of the resin matrix, avoiding performance degradation of the coating due to excessive stretching or deformation of dynamic bonds during repeated friction, and at the same time making up for the shortcomings of the simple dynamic crosslinking system in terms of insufficient resistance to long-term cyclic wear.

[0024] Preferably, the amount of emulsifier is 2%-4% of the total mass of the monomers; and the amount of initiator is 0.3%-0.7% of the total mass of the monomers.

[0025] Preferably, the emulsifier is a mixture of NP-10 and SDS in a mass ratio of (1-1.5):1.

[0026] By employing the above technical solutions, NP-10 can reduce the surface tension of the aqueous phase, helping oil-soluble monomers (such as methyl methacrylate and organosilicon monomers) disperse into tiny droplets. Its polyoxyethylene ether chains can form a steric hindrance film, preventing droplet aggregation. SDS, on the other hand, provides negative charges by adsorbing onto the surface of monomer droplets and nanoparticles, forming an electric double layer, enhancing electrostatic repulsion, and further inhibiting particle agglomeration. When the two are combined, NP-10 can compensate for the insufficient steric hindrance and easy flocculation of SDS when used alone, while SDS enhances the shortcomings of NP-10 when used alone, which has weak electrostatic repulsion and limited ability to disperse nanoparticles. Together, they construct a more stable protective barrier, ensuring uniform particle size of the monomer emulsion during polymerization and efficiently dispersing nanocomposite particles. This provides a uniform microenvironment for subsequent supramolecular anchoring and dynamic crosslinking reactions, ultimately improving the overall performance stability of the resin and coating.

[0027] Secondly, this application provides a wear-resistant silicone-modified acrylate resin for coatings, employing the following technical solution:

[0028] The wear-resistant silicone-modified acrylate resin for coatings is prepared using the above-described process.

[0029] By adopting the above technical solution, the wear-resistant silicone-modified acrylate resin for coatings of this application has high wear resistance and strong compatibility. The resin can be directly compounded with conventional coating components and is suitable for various substrates such as metal, wood, and plastic.

[0030] In summary, this application has the following beneficial effects:

[0031] 1. The wear-resistant silicone-modified acrylate resin for coatings of this application is obtained by a supramolecular anchoring and dynamic covalent cross-linking reaction between AD / carboxyl bifunctionalized nanocomposite particles and silicone-modified acrylate resin containing β-cyclodextrin and hydrazine groups. The adamantyl group on the surface of the nanocomposite particles and the β-cyclodextrin group in the resin molecular chain achieve supramolecular anchoring through host-guest recognition. At the same time, the hydrazine group in the resin molecular chain reacts with the carboxyl group on the surface of the nanocomposite particles to form hydrazone bonds to achieve dynamic covalent cross-linking. The dual-mechanism cross-linking solves the problems of interfacial separation and void defects caused by the polarity difference between nanomaterials and resin. The obtained silicone-modified acrylate resin has good wear resistance.

[0032] 2. In this application, the introduction of an appropriate amount of natural nanocellulose into AD / carboxyl bifunctionalized nanocomposite particles can form a synergistic reinforcing structure of rigid core-lamellae barrier-fiber skeleton, which further improves the wear resistance of the prepared organosilicon modified acrylate resin.

[0033] 3. This application adds an appropriate amount of isocyanate monomer to an organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine. The -NCO group can react with the hydrazine group of acryloyl hydrazine in the resin and the hydroxyl group on the surface of the nanocomposite particles to form dynamic urea bonds. This forms a urea bond-hydrazone bond double dynamic cross-linking network with the original acylhydrazone bonds. The two work together to enhance the energy dissipation efficiency of bond breaking and recombination, and reduce coating damage during wear.

[0034] 4. This application adds an appropriate amount of divinylbenzene to an organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine. The two double bonds in the divinylbenzene molecule participate in free radical copolymerization, forming a small number of permanent crosslinking points in the resin network. These permanent crosslinking points can construct a rigid skeleton and improve the wear resistance of the resin. Detailed Implementation

[0035] The present application will be further described in detail below with reference to the embodiments. Unless otherwise specified, all raw materials involved in the present application can be obtained commercially.

[0036] Example 1

[0037] This embodiment provides a preparation process for a wear-resistant silicone-modified acrylate resin for coatings, including the following steps:

[0038] (1) Composite nanoparticle dispersion: 0.25 kg of nanodiamond with a particle size of 5-10 nm and 0.08 kg of graphene oxide were dispersed in 8.3 kg of deionized water and sonicated at 500 W for 30 min; 0.09 kg of adamantane (CAS: 768-94-5) was added and stirred at 800 rpm at 60 °C for 2 h; 0.05 kg of succinic anhydride was added and stirred for another 1 h; centrifuged at 2500 rpm for 15 min; the precipitate was washed three times with deionized water and then redispersed in 5 kg of water for later use.

[0039] (2) Organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine: 40 kg of methyl methacrylate, 25 kg of isooctyl acrylate, 8 kg of γ-methacryloyloxypropyltrimethoxysilane, 4 kg of β-cyclodextrin acrylate, 5 kg of acryloyl hydrazine (CAS: 3128-32-3) and 1 kg of glycidyl methacrylate were mixed evenly and then mixed with 1.66 kg of NP-10 and 65 kg of deionized water. The mixture was stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion was added to the reaction vessel, heated to 80 °C, and 0.25 kg of potassium persulfate was added. The mixture was reacted for 30 min to form a seed emulsion. The remaining pre-emulsion was added dropwise and kept at 80 °C for 3 h to obtain an organosilicon modified acrylate resin emulsion containing β-CD and hydrazine.

[0040] The preparation method of β-cyclodextrin ester of acrylic acid is as follows: 5 kg of β-cyclodextrin is dissolved in 50 L of dry N,N-dimethylformamide and stirred at 60 °C until completely dissolved. The solution is then cooled to 0 °C and protected with nitrogen gas. 1.5 L of triethylamine is added to the system and stirred for 10 min. Then, 10 g of hydroquinone is added, followed by 0.8 L of acryloyl chloride. The temperature is kept below 5 °C during the addition. After the addition is complete, the temperature is raised to 30 °C and the reaction is continued for 4 h. After the reaction is complete, the reaction solution is poured into 200 L of ice-cold ethanol and allowed to stand to precipitate. The precipitate is collected by filtration and washed three times with anhydrous ethanol (30 L each time). Finally, the precipitate is dried in a vacuum drying oven at 40 °C for 12 h to obtain β-cyclodextrin ester of acrylic acid.

[0041] (3) The above composite nanoparticle dispersion was slowly added to the organosilicon modified acrylate resin emulsion containing β-CD and hydrazine groups, and stirred at room temperature for 1 hour; the temperature was raised to 50°C and reacted for 2 hours; the temperature was lowered to 40°C, the pH was adjusted to 7 with 25% ammonia water, and then filtered through a 100-mesh nylon filter to obtain wear-resistant organosilicon modified acrylate resin for coatings.

[0042] Example 2

[0043] This embodiment provides a preparation process for a wear-resistant silicone-modified acrylate resin for coatings, including the following steps:

[0044] (1) Composite nanoparticle dispersion: 0.6 kg of nanodiamond with a particle size of 5-10 nm and 0.22 kg of graphene oxide were dispersed in 9 kg of deionized water and sonicated at 550 W for 30 min; 0.15 kg of adamantane (CAS: 768-94-5) was added and stirred at 800 rpm at 60 °C for 2 h; 0.1 kg of succinic anhydride was added and stirred for another 1 h; centrifuged at 3000 rpm for 10 min; the precipitate was washed three times with deionized water and then redispersed in 5 kg of water for later use.

[0045] (2) Organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine: 45 kg of methyl methacrylate, 30 kg of isooctyl acrylate, 10 kg of γ-methacryloyloxypropyltrimethoxysilane, 6 kg of β-cyclodextrin acrylate, 7 kg of acryloyl hydrazine (CAS: 3128-32-3) and 2 kg of glycidyl methacrylate were mixed evenly and then mixed with 3 kg of NP-10 and 65 kg of deionized water. The mixture was stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion was added to the reaction vessel, heated to 80 °C, and 0.5 kg of potassium persulfate was added. The reaction was carried out for 30 min to form a seed emulsion. The remaining pre-emulsion was added dropwise and kept at 80 °C for 3 h to obtain an organosilicon modified acrylate resin emulsion containing β-CD and hydrazine.

[0046] The preparation method of β-cyclodextrin ester of acrylic acid is as follows: 5 kg of β-cyclodextrin is dissolved in 50 L of dry N,N-dimethylformamide and stirred at 60 °C until completely dissolved. The solution is then cooled to 0 °C and protected with nitrogen gas. 1.5 L of triethylamine is added to the system and stirred for 10 min. Then, 10 g of hydroquinone is added, followed by 0.8 L of acryloyl chloride. The temperature is kept below 5 °C during the addition. After the addition is complete, the temperature is raised to 30 °C and the reaction is continued for 4 h. After the reaction is complete, the reaction solution is poured into 200 L of ice-cold ethanol and allowed to stand to precipitate. The precipitate is collected by filtration and washed three times with anhydrous ethanol (30 L each time). Finally, the precipitate is dried in a vacuum drying oven at 40 °C for 12 h to obtain β-cyclodextrin ester of acrylic acid.

[0047] (3) The above composite nanoparticle dispersion was slowly added to the organosilicon modified acrylate resin emulsion containing β-CD and hydrazine groups, and stirred at room temperature for 1 hour; the temperature was raised to 50°C and reacted for 2 hours; the temperature was lowered to 40°C, the pH was adjusted to 7 with 25% ammonia water, and then filtered through a 100-mesh nylon filter to obtain wear-resistant organosilicon modified acrylate resin for coatings.

[0048] Example 3

[0049] This embodiment provides a preparation process for a wear-resistant silicone-modified acrylate resin for coatings, including the following steps:

[0050] (1) Composite nanoparticle dispersion: 0.9 kg of nanodiamond with a particle size of 5-10 nm and 0.35 kg of graphene oxide were dispersed in 95 kg of deionized water and sonicated at 600 W for 30 min; 0.23 kg of adamantane (CAS: 768-94-5) was added and stirred at 800 rpm at 60 °C for 2 h; 0.16 kg of succinic anhydride was added and stirred for another 1 h; centrifuged at 3500 rpm for 5 min; the precipitate was washed three times with deionized water and then redispersed in 5 kg of water for later use.

[0051] (2) Organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine: 50 kg of methyl methacrylate, 32 kg of isooctyl acrylate, 12 kg of γ-methacryloyloxypropyltrimethoxysilane, 7 kg of β-cyclodextrin acrylate, 8 kg of acryloyl hydrazine (CAS: 3128-32-3) and 3 kg of glycidyl methacrylate were mixed evenly and then mixed with 4.5 kg of NP-10 and 65 kg of deionized water. The mixture was stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion was added to the reaction vessel, heated to 80 °C, and 0.8 kg of potassium persulfate was added. The reaction was carried out for 30 min to form a seed emulsion. The remaining pre-emulsion was added dropwise and kept at 80 °C for 3 h to obtain an organosilicon modified acrylate resin emulsion containing β-CD and hydrazine.

[0052] The preparation method of β-cyclodextrin ester of acrylic acid is as follows: 5 kg of β-cyclodextrin is dissolved in 50 L of dry N,N-dimethylformamide and stirred at 60 °C until completely dissolved. The solution is then cooled to 0 °C and protected with nitrogen gas. 1.5 L of triethylamine is added to the system and stirred for 10 min. Then, 10 g of hydroquinone is added, followed by 0.8 L of acryloyl chloride. The temperature is kept below 5 °C during the addition. After the addition is complete, the temperature is raised to 30 °C and the reaction is continued for 4 h. After the reaction is complete, the reaction solution is poured into 200 L of ice-cold ethanol and allowed to stand to precipitate. The precipitate is collected by filtration and washed three times with anhydrous ethanol (30 L each time). Finally, the precipitate is dried in a vacuum drying oven at 40 °C for 12 h to obtain β-cyclodextrin ester of acrylic acid.

[0053] (3) The above composite nanoparticle dispersion was slowly added to the organosilicon modified acrylate resin emulsion containing β-CD and hydrazine groups, and stirred at room temperature for 1 hour; the temperature was raised to 50°C and reacted for 2 hours; the temperature was lowered to 40°C, the pH was adjusted to 7 with 25% ammonia water, and then filtered through a 100-mesh nylon filter to obtain wear-resistant organosilicon modified acrylate resin for coatings.

[0054] Example 4

[0055] This embodiment is basically the same as embodiment 2, except that in step (1) the composite nanoparticle dispersion: 0.6 kg of nanodiamond, 0.22 kg of graphene oxide and 0.15 kg of natural nanocellulose with a particle size of 5-10 nm are dispersed in 9 kg of deionized water and sonicated at 550 W for 30 min; 0.15 kg of adamantane (CAS: 768-94-5) is added and stirred at 800 rpm at 60 °C for 2 h, then 0.1 kg of succinic anhydride is added and stirred for another 1 h, then centrifuged at 3000 rpm for 10 min, the precipitate is washed 3 times with deionized water and then redispersed in 5 kg of water for later use.

[0056] Example 5

[0057] This embodiment is basically the same as embodiment 4, except that step (2) contains β-cyclodextrin and hydrazine-based organosilicon modified acrylate resin: 45 kg of methyl methacrylate, 30 kg of isooctyl acrylate, 10 kg of γ-methacryloyloxypropyltrimethoxysilane, 6 kg of β-cyclodextrin acrylate, 7 kg of acryloyl hydrazine (CAS: 3128-32-3), 2 kg of glycidyl methacrylate and 0.75 kg of isocyanate ethyl methacrylate (isocyanate monomer) are mixed evenly, and then mixed with 3 kg of NP-10 and 65 kg of deionized water. The mixture is stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion is added to the reaction vessel, heated to 80°C, and 0.5 kg of potassium persulfate is added. The mixture is reacted for 30 min to form a seed emulsion. The remaining pre-emulsion is added dropwise, and the mixture is kept at 80°C for 3 h to obtain an organosilicon modified acrylate resin emulsion containing β-CD and hydrazine.

[0058] Example 6

[0059] This embodiment is basically the same as Example 4, except that step (2) involves organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine: 45 kg of methyl methacrylate, 30 kg of isooctyl acrylate, 10 kg of γ-methacryloyloxypropyltrimethoxysilane, 6 kg of β-cyclodextrin acrylate, 7 kg of acryloyl hydrazine (CAS: 3128-32-3), 2 kg of glycidyl methacrylate and 0.3 kg of divinylbenzene are mixed evenly and then mixed with 3 kg of NP-10 and 65 kg of deionized water. The mixture is stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion is added to the reaction vessel, heated to 80°C, and 0.5 kg of potassium persulfate is added. The mixture is reacted for 30 min to form a seed emulsion. The remaining pre-emulsion is added dropwise, and the mixture is kept at 80°C for 3 h to obtain an organosilicon-modified acrylate resin emulsion containing β-CD and hydrazine.

[0060] Example 7

[0061] This embodiment is basically the same as embodiment 4, except that step (2) contains β-cyclodextrin and hydrazine-based organosilicon modified acrylate resin: 45 kg of methyl methacrylate, 30 kg of isooctyl acrylate, 10 kg of γ-methacryloyloxypropyltrimethoxysilane, 6 kg of β-cyclodextrin acrylate, 7 kg of acryloyl hydrazine (CAS: 3128-32-3), 2 kg of glycidyl methacrylate, 0.75 kg of isocyanate ethyl methacrylate (isocyanate monomer) and 0.3 kg of divinylbenzene are mixed evenly, and then mixed with 3 kg of NP-10 and 65 kg of deionized water. The mixture is stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion is added to the reaction vessel, heated to 80°C, and 0.5 kg of potassium persulfate is added. The mixture is reacted for 30 min to form a seed emulsion. The remaining pre-emulsion is added dropwise, and the mixture is kept at 80°C for 3 h to obtain an organosilicon modified acrylate resin emulsion containing β-CD and hydrazine.

[0062] Example 8

[0063] This embodiment is basically the same as embodiment 7, except that in step (1) the composite nanoparticle dispersion: 0.6 kg of nanodiamond, 0.22 kg of graphene oxide and 0.1 kg of natural nanocellulose with a particle size of 5-10 nm are dispersed in 9 kg of deionized water and sonicated at 550 W for 30 min; 0.15 kg of adamantane (CAS: 768-94-5) is added and stirred at 800 rpm at 60 °C for 2 h, then 0.1 kg of succinic anhydride is added and stirred for another 1 h, then centrifuged at 3000 rpm for 10 min, the precipitate is washed 3 times with deionized water and then redispersed in 5 kg of water for later use;

[0064] Step (2) Organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine: 45 kg methyl methacrylate, 30 kg isooctyl acrylate, 10 kg γ-methacryloyloxypropyltrimethoxysilane, 6 kg β-cyclodextrin acrylate, 7 kg acryloyl hydrazine (CAS: 3128-32-3), 2 kg glycidyl methacrylate, 0.5 kg isocyanate ethyl methacrylate (isocyanate monomer) and 0.1 kg divinylbenzene are mixed evenly, and then mixed with 3 kg NP-10 and 65 kg deionized water. The mixture is stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion is added to the reaction vessel, heated to 80℃, and 0.5 kg potassium persulfate is added. The mixture is reacted for 30 min to form a seed emulsion. The remaining pre-emulsion is added dropwise, and the mixture is kept at 80℃ for 3 h to obtain an organosilicon modified acrylate resin emulsion containing β-CD and hydrazine.

[0065] Example 9

[0066] This embodiment is basically the same as embodiment 7, except that in step (1) the composite nanoparticle dispersion: 0.6 kg of nanodiamond, 0.22 kg of graphene oxide and 0.2 kg of natural nanocellulose with a particle size of 5-10 nm are dispersed in 9 kg of deionized water and sonicated at 550 W for 30 min; 0.15 kg of adamantane (CAS: 768-94-5) is added and stirred at 800 rpm at 60 °C for 2 h, then 0.1 kg of succinic anhydride is added and stirred for another 1 h, then centrifuged at 3000 rpm for 10 min, the precipitate is washed 3 times with deionized water and then redispersed in 5 kg of water for later use;

[0067] Step (2) Organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine: 45 kg methyl methacrylate, 30 kg isooctyl acrylate, 10 kg γ-methacryloyloxypropyltrimethoxysilane, 6 kg β-cyclodextrin acrylate, 7 kg acryloyl hydrazine (CAS: 3128-32-3), 2 kg glycidyl methacrylate, 1 kg isocyanate ethyl methacrylate (isocyanate monomer) and 0.5 kg divinylbenzene are mixed evenly, and then mixed with 3 kg NP-10 and 65 kg deionized water. The mixture is stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion is added to the reaction vessel, heated to 80℃, and 0.5 kg potassium persulfate is added. The mixture is reacted for 30 min to form a seed emulsion. The remaining pre-emulsion is added dropwise, and the mixture is kept at 80℃ for 3 h to obtain an organosilicon modified acrylate resin emulsion containing β-CD and hydrazine.

[0068] Example 10

[0069] This embodiment is basically the same as Embodiment 7, except that step (2) contains organosilicon-modified acrylate resin with β-cyclodextrin and hydrazine: 45 kg methyl methacrylate, 30 kg isooctyl acrylate, 10 kg γ-methacryloyloxypropyltrimethoxysilane, 6 kg β-cyclodextrin acrylate, 7 kg acryloyl hydrazine (CAS: 3128-32-3), 2 kg glycidyl methacrylate, and 0.75 kg isocyanate ethyl methacrylate (isocyanate) The monomer and 0.3 kg of divinylbenzene were mixed evenly, and then mixed with 1.5 kg of NP-10, 1.5 kg of SDS and 65 kg of deionized water. The mixture was stirred at 1200 rpm for 30 min to form a pre-emulsion. One-third of the pre-emulsion was added to the reaction vessel, heated to 80 °C, and 0.5 kg of potassium persulfate was added. The mixture was reacted for 30 min to form a seed emulsion. The remaining pre-emulsion was added dropwise, and the mixture was kept at 80 °C for 3 h to obtain an organosilicon-modified acrylate resin emulsion containing β-CD and hydrazine groups.

[0070] Example 11

[0071] This embodiment is basically the same as Embodiment 7, except that step (2) contains β-cyclodextrin and hydrazine-based organosilicon-modified acrylate resin: 45 kg methyl methacrylate, 30 kg isooctyl acrylate, 10 kg γ-methacryloyloxypropyltrimethoxysilane, 6 kg β-cyclodextrin acrylate, 7 kg acryloyl hydrazine (CAS: 3128-32-3), 2 kg glycidyl methacrylate, and 0.75 kg isocyanate ethyl methacrylate (isocyanate monoethyl methacrylate). Mix 0.3 kg of divinylbenzene with 1.67 kg of NP-10, 1.33 kg of SDS, and 65 kg of deionized water. Stir at 1200 rpm for 30 min to form a pre-emulsion. Add 1 / 3 of the pre-emulsion to a reaction vessel, heat to 80 °C, add 0.5 kg of potassium persulfate, and react for 30 min to form a seed emulsion. Add the remaining pre-emulsion dropwise and keep at 80 °C for 3 h to obtain an organosilicon-modified acrylate resin emulsion containing β-CD and hydrazine groups.

[0072] Example 12

[0073] This embodiment is basically the same as Embodiment 6, except that step (2) contains β-cyclodextrin and hydrazine-based organosilicon-modified acrylate resin: 45 kg methyl methacrylate, 30 kg isooctyl acrylate, 10 kg γ-methacryloyloxypropyltrimethoxysilane, 6 kg β-cyclodextrin acrylate, 7 kg acryloyl hydrazine (CAS: 3128-32-3), 2 kg glycidyl methacrylate, and 0.75 kg isocyanate ethyl methacrylate (isocyanate). The monomer and 0.3 kg of divinylbenzene were mixed evenly, and then mixed with 1.8 kg of NP-10, 1.2 kg of SDS and 65 kg of deionized water. The mixture was stirred at 1200 rpm for 30 min to form a pre-emulsion. One-third of the pre-emulsion was added to the reaction vessel, heated to 80 °C, and 0.5 kg of potassium persulfate was added. The mixture was reacted for 30 min to form a seed emulsion. The remaining pre-emulsion was added dropwise, and the mixture was kept at 80 °C for 3 h to obtain an organosilicon-modified acrylate resin emulsion containing β-CD and hydrazine groups.

[0074] Comparative Example 1

[0075] This comparative example provides a preparation process for a wear-resistant silicone-modified acrylate resin for coatings, including the following steps:

[0076] (1) Composite nanoparticle dispersion: 0.25 kg of nanodiamond with a particle size of 5-10 nm and 0.08 kg of graphene oxide are dispersed in 5 kg of water for later use;

[0077] (2) Organosilicon modified acrylate resin: 40 kg of methyl methacrylate, 25 kg of isooctyl acrylate, 8 kg of γ-methacryloyloxypropyltrimethoxysilane and 1 kg of glycidyl methacrylate were mixed evenly, and then mixed with 1.66 kg of NP-10 and 65 kg of deionized water. The mixture was stirred at 1200 rpm for 30 min to form a pre-emulsion. 1 / 3 of the pre-emulsion was added to the reaction vessel, heated to 80 °C, and 0.25 kg of potassium persulfate was added. The mixture was reacted for 30 min to form a seed emulsion. The remaining pre-emulsion was added dropwise, and the mixture was kept at 80 °C for 3 h to obtain the organosilicon modified acrylate resin emulsion.

[0078] (3) Add the above composite nanoparticle dispersion to the organosilicon-modified acrylate resin emulsion and stir at room temperature for 1 hour to obtain wear-resistant organosilicon-modified acrylate resin for coatings.

[0079] Performance testing

[0080] Coating: Add 10 kg of deionized water, 0.8 kg of dispersant (SN-5040), and 0.2 kg of defoamer (BYK-028) to a dispersion tank. Add 4 kg of zinc phosphate while stirring at 600 rpm and stir for 10 min until uniformly mixed. Grind the mixture with a sander until the fineness is ≤20 μm to obtain a color paste. Transfer the color paste to a paint mixing tank and slowly add 75 kg of wear-resistant silicone-modified acrylate resin for coatings obtained in each example and comparative example at 500 rpm. After stirring for 20 min, add 3 kg of film-forming aid (dodecyl alcohol ester), 0.45 kg of leveling agent (EFKA-3777), 0.15 kg of defoamer (BYK-028), and 0.2 kg of thickener (TT-935) in sequence and stir for 15 min until uniform. Then add 16.2 kg of deionized water and filter through a 200-mesh filter to obtain the coating.

[0081] Substrate pretreatment: The metal substrate is sprayed with an alkaline degreasing agent to remove oil, then sandblasted (Sa2.5 grade), and then dried with hot air at 80℃ for 5 minutes;

[0082] Coating: The above coating is sprayed onto the substrate surface through a spray gun (spray gun diameter 2.0mm, air pressure 0.5Mpa) to form a coating with a thickness of 50μm. After leveling at room temperature for 10 minutes for surface drying, it is baked in an 80℃ hot air circulating oven for 30 minutes to cure and dry.

[0083] (1) Abrasion resistance: Tested according to GB / T 1768-2009, and the test results are shown in Table 1.

[0084] (2) Pencil hardness: The test was conducted in accordance with GB / T 6739-2009, and the test results are shown in Table 1.

[0085] (3) Adhesion: The test was conducted in accordance with GB / T 9286-1998, and the test results are shown in Table 1.

[0086] (4) VOC content: The test was conducted in accordance with GB 30981-2020, and the test results are shown in Table 1.

[0087] Table 1 Performance test data of Examples 1-12 and Comparative Example 1

[0088]

[0089] As can be seen from Example 1 and Comparative Example 1 and Table 1, the adamantyl groups on the surface of the nanocomposite particles of this application achieve supramolecular anchoring with the β-cyclodextrin groups in the resin molecular chain through host-guest recognition; at the same time, the hydrazine groups in the resin molecular chain react with the carboxyl groups on the surface of the nanocomposite particles to form hydrazone bonds, achieving dynamic covalent cross-linking. Compared with simple physical mixing, this method utilizes the ultra-high hardness of nanodiamonds, the crack-blocking effect of graphene oxide, and the high bond energy characteristics of organosilicon Si-O-Si bonds to overcome the wear resistance shortcomings of traditional acrylate resins from both the reinforcing phase and matrix levels. Furthermore, it solves the compatibility problem between organosilicon and acrylate resins through chemical copolymerization, and solves the problems of interface separation and void defects caused by the polarity difference between nanomaterials and resins through dual-mechanism cross-linking. The resulting coating has good wear resistance.

[0090] As can be seen from Examples 2 and 4 and Table 1, this application introduces an appropriate amount of natural nanocellulose into AD / carboxyl bifunctionalized nanocomposite particles. Natural nanocellulose, with its large aspect ratio, can act as a fiber skeleton to bridge nanodiamonds and graphene oxide, forming a three-dimensional interconnected network. This significantly improves the overall crack propagation resistance of the particles and avoids the problem of easy detachment when single particles are dispersed. Its abundant hydroxyl groups on the surface can also form hydrogen bonds with the carboxyl groups of graphene oxide and the hydroxyl groups of nanodiamonds, enhancing the bonding stability of the three. At the same time, it assists in the uniform grafting of adamantane and succinic anhydride on the particle surface, reducing the aggregation of functional sites and further improving the wear resistance of the resulting coating.

[0091] As can be seen from Examples 4 and 5 and Table 1, this application, by adding an appropriate amount of isocyanate monomer to the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine, allows its double bonds to participate in free radical copolymerization simultaneously with methyl methacrylate, organosilicon monomers, etc., stably grafting the -NCO group onto the resin backbone and avoiding uneven distribution caused by physical mixing. At the same time, the -NCO group can react with the hydrazine group of acryloyl hydrazine in the resin and the hydroxyl groups on the surface of the nanocomposite particles to form dynamic urea bonds, constructing a urea bond-hydrazone bond double dynamic crosslinking network with the original acylhydrazone bonds. The two work synergistically to enhance the energy dissipation efficiency of bond breaking and recombination, reduce coating damage during wear, and further improve the wear resistance of the prepared coating.

[0092] As can be seen from Examples 4 and 6 and Table 1, this application adds an appropriate amount of divinylbenzene to an organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine groups. The two double bonds of divinylbenzene participate in free radical copolymerization, forming a small number of permanent crosslinking points in the resin network. These permanent crosslinking points can construct a rigid skeleton, effectively enhancing the structural stability and fatigue resistance of the resin matrix, avoiding performance degradation of the coating due to excessive stretching or deformation of dynamic bonds during repeated friction, and compensating for the shortcomings of the simple dynamic crosslinking system in resisting long-term cyclic wear, further improving the wear resistance of the prepared coating.

[0093] As can be seen from Examples 4 and 7 and Table 1, this application achieves complementary performance by simultaneously adding isocyanate monomers and divinylbenzene (DVB) to an organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine. This can be achieved through a synergistic mechanism of permanent covalent crosslinking and dynamic reversible crosslinking. This not only solves the problem of coating brittleness caused by adding DVB alone, but also makes up for the shortcoming of insufficient fatigue resistance when adding isocyanate alone, further improving the wear resistance and overall performance stability of the coating.

[0094] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A preparation process for a wear-resistant silicone-modified acrylate resin for coatings, characterized in that, It was obtained by undergoing supramolecular anchoring and dynamic covalent cross-linking reaction between AD / carboxyl bifunctionalized nanocomposite particles and organosilicon modified acrylate resin containing β-cyclodextrin and hydrazine groups; The AD / carboxyl bifunctionalized nanocomposite particles were prepared by modifying nanodiamond and graphene oxide with adamantane and succinic anhydride. The raw materials, by weight, include: 2.5-9 parts nano-diamond, 0.8-3.5 parts graphene oxide, 0.9-2.3 parts adamantane, 0.5-1.6 parts succinic anhydride, and 83-95 parts deionized water; The organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine is prepared by copolymerization of organosilicon monomers, acrylate monomers, β-cyclodextrin acrylate, acryloyl hydrazine, and glycidyl methacrylate. It comprises the following raw materials in parts by weight: 40-50 parts of methyl methacrylate, 25-32 parts of isooctyl acrylate, 8-12 parts of γ-methacryloyloxypropyltrimethoxysilane, 4-7 parts of β-cyclodextrin acrylate, 5-8 parts of acryloyl hydrazine, and 1-3 parts of glycidyl methacrylate.

2. The preparation process of the wear-resistant organosilicon-modified acrylate resin for coatings according to claim 1, characterized in that, The preparation method of the AD / carboxyl bifunctional nanocomposite particles is as follows: nanodiamond and graphene oxide are dispersed in deionized water, ultrasonically treated, and then adamantane is added. After stirring and reacting, succinic anhydride is added and the reaction continues. After centrifugation and washing, the AD / carboxyl bifunctional nanocomposite particles are obtained.

3. The preparation process of the wear-resistant organosilicon-modified acrylate resin for coatings according to claim 2, characterized in that, The raw materials for preparing the AD / carboxyl bifunctional nanocomposite particles also include 1-2 parts by weight of natural nanocellulose; the preparation method of the AD / carboxyl bifunctional nanocomposite particles is as follows: nanodiamond, graphene oxide and natural nanocellulose are dispersed in deionized water, ultrasonically treated and then adamantane is added, the reaction is stirred and then succinic anhydride is added to continue the reaction, and then the particles are centrifuged and washed to obtain the AD / carboxyl bifunctional nanocomposite particles.

4. The preparation process of the wear-resistant silicone-modified acrylate resin for coatings according to claim 2, characterized in that, The ultrasonic treatment uses a power of 500-600W, a centrifugation speed of 2500-3500rpm, and a centrifugation time of 5-15min.

5. The preparation process of the wear-resistant silicone-modified acrylate resin for coatings according to claim 1, characterized in that, The preparation method of the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine is as follows: the monomer raw material is mixed with an emulsifier, deionized water is added and stirred to form a pre-emulsion, a portion of the pre-emulsion is heated and an initiator is added to react and form a seed emulsion, and the remaining pre-emulsion is added dropwise and kept at the temperature to obtain the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine.

6. The preparation process of the wear-resistant silicone-modified acrylate resin for coatings according to claim 5, characterized in that, The monomer raw materials of the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine also include 0.5-1 parts by weight of isocyanate monomer.

7. The preparation process of the wear-resistant silicone-modified acrylate resin for coatings according to claim 5, characterized in that, The monomer raw materials of the organosilicon-modified acrylate resin containing β-cyclodextrin and hydrazine also include 0.1-0.5 parts by weight of divinylbenzene.

8. The preparation process of the wear-resistant silicone-modified acrylate resin for coatings according to claim 5, characterized in that, The emulsifier is used at a rate of 2%-4% of the total monomer mass; the initiator is used at a rate of 0.3%-0.7% of the total monomer mass.

9. The preparation process of the wear-resistant organosilicon-modified acrylate resin for coatings according to claim 8, characterized in that, The emulsifier is a mixture of NP-10 and SDS in a mass ratio of (1-1.5):

1.

10. A wear-resistant silicone-modified acrylate resin for coatings, characterized in that, It is prepared using the preparation process of the wear-resistant organosilicon-modified acrylate resin for coatings as described in any one of claims 1-9.

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