Organosilicon acrylamide copolymer and preparation method thereof

Abstract

The invention relates to an organic silicon acrylamide copolymer and a preparation method thereof. The organic silicon acrylamide copolymer comprises the following components in parts by mass: 10-20 parts of an organic silicon monomer, 40-50 parts of an acrylamide monomer, 0.5-1.5 parts of an initiator, 3-5 parts of a cross-linking agent, 50-70 parts of a solvent, 0.5-1.5 parts of a flatting agent and 0.3-0.5 part of a defoaming agent. The preparation method comprises the following steps: adding an organic silicon monomer, an acrylamide monomer and a cross-linking agent into a solvent, and stirring to obtain a mixture; introducing neutral gas into the mixture to obtain an anaerobic reaction system; heating the oxygen-free reaction system, adding an initiator, stirring for reaction, starting ultraviolet, heating for stirring for reaction, cooling after the reaction is finished, adding a flatting agent and a defoaming agent, stirring and sieving to obtain the organic silicon acrylamide copolymer. The method has the effect of improving the stability of the copolymer, and can reduce the phase separation phenomenon caused by polarity difference.

Description

Technical Field

[0001] This application relates to the technical field of polymer materials, and particularly to a silicone acrylamide copolymer and a preparation method thereof. Background Art

[0002] In the field of materials science, silicone acrylamide copolymers have shown broad application prospects due to their combination of excellent properties of silicone, such as low surface energy, good weather resistance and flexibility, as well as the hydrophilicity and reactivity of acrylamide, and have attracted much attention in industries such as coatings, adhesives, and textile auxiliaries.

[0003] Currently, the copolymerization of silicone and acrylamide faces challenges. The polarity difference between the silicone chain segment and acrylamide easily leads to phase separation, affecting the stability of the copolymer. For example, in the application of coatings, due to the unstable performance of the copolymer, the film-forming quality of the coatings is uneven, affecting the appearance and protective performance of the coatings, so improvement is needed. Summary of the Invention

[0004] In order to improve the stability of the silicone acrylamide copolymer, this application provides a silicone acrylamide copolymer and a preparation method thereof.

[0005] The silicone acrylamide copolymer and the preparation method provided by this application adopt the following technical solutions: In the first aspect, the silicone acrylamide copolymer provided by this application adopts the following technical solutions: A silicone acrylamide copolymer comprising the following components in parts by mass: Silicone monomer 10 - 20 parts Acrylamide monomer 40 - 50 parts Initiator 0.5 - 1.5 parts Crosslinking agent 3 - 5 parts Solvent 50 - 70 parts Leveling agent 0.5 - 1.5 parts Defoaming agent 0.3 - 0.5 parts.

[0006] Silicone monomers have low surface energy, good flexibility, and high and low temperature resistance characteristics. Their molecular structure can endow the molecular chain with a certain degree of freedom of movement in the copolymer system, which helps the orderly arrangement of molecules during the film-forming process, forming a uniform and continuous film layer; the high bond energy of the silicon-oxygen bond enables the copolymer to resist the erosion of the external environment and enhance weather resistance; acrylamide monomers contain polar amide groups, which are easy to form hydrogen bonds and other interactions with other substances, and help the mutual attraction and combination between molecules during film formation, improving the denseness and integrity of the film and enhancing the film-forming property; the acrylamide group can form a strong adhesion force with the substrate surface, enhancing the combination of the copolymer and the substrate; the initiator promotes the polymerization reaction of the silicone monomer and the acrylamide monomer to form a chemical bond connection, enabling monomers with different polarities to combine at the molecular level, reducing the phase separation tendency caused by polarity differences, and enhancing the stability of the copolymer; the cross-linking agent forms chemical bonds between the copolymer molecular chains, acting as a bridge to reduce the phase separation problem caused by polarity differences, constructing a three-dimensional network structure, enhancing the interaction between molecules, improving the mechanical strength and stability of the film, and thus enhancing the film-forming property and adhesion; at the same time, this cross-linked structure can also better resist the damage of the external environment to the copolymer and enhance weather resistance.

[0007] Preferably, the silicone monomer includes a dimethylcyclosiloxane mixture, methylhydrogen silicone oil, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0008] The dimethylcyclosiloxane mixture has good flexibility and fluidity. The silicon-oxygen bond in its molecular structure endows it with low surface energy characteristics, improving the contact performance between the copolymer and different substrates, thereby enhancing the adhesion performance; the silicon-hydrogen bond in methylhydrogen silicone oil gives it active reactivity, and it can undergo cross-linking reactions with other monomers during polymerization, enhancing the interaction between molecules, helping to connect monomers with large polarity differences, and reducing the phase separation trend caused by polarity differences; β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane contains epoxy groups and siloxane groups. The epoxy groups can undergo ring-opening reactions to form chemical bonds with other monomers, increasing the connection points between molecular chains and making the copolymer molecular structure more compact and stable; the siloxane groups further enhance the weather resistance and low surface energy characteristics of the copolymer; these silicone monomers act synergistically, effectively reducing the adverse effects of polarity differences on the stability of the copolymer through the interaction and reaction between different groups, enhancing the stability of the copolymer, and thus enhancing its film-forming property, adhesion, and weather resistance.

[0009] Preferably, the mass ratio of the dimethylcyclosiloxane mixture, methylhydrogen silicone oil, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane is 2:1:(0.5 - 1.5).

[0010] The organosilicon monomers compounded according to the above mass ratio can effectively reduce the influence brought by the polarity difference, improve the stability of the organosilicon acrylamide copolymer, and thus improve its film-forming property, adhesiveness and weather resistance.

[0011] Preferably, the acrylamide monomer includes N-methylolacrylamide and N,N'-divinyl bisacrylamide.

[0012] N-methylolacrylamide contains a hydroxymethyl group, has strong polarity and reactivity. In the polymerization reaction, it can react with the active groups in the organosilicon monomer, connect through chemical bonds, effectively shorten the distance from the organosilicon monomer, and reduce the separation tendency caused by the polarity difference between the two; at the same time, the hydroxymethyl group can form intermolecular forces such as hydrogen bonds in the copolymer, enhance the interaction between molecular chains, and improve the stability of the copolymer; the vinyl group in the N,N'-divinyl bisacrylamide molecule endows it with good polymerization activity, can polymerize efficiently with other monomers, and build a stable copolymer molecular skeleton. The polarity of its amide group matches that of N-methylolacrylamide and forms a complement to the polarity of the organosilicon monomer, which helps to disperse evenly during the polymerization process and reduce the interference of the polarity difference; when the stable copolymer structure forms a film, it can make the molecules arrange orderly to form a flat and continuous film layer, significantly improving the film-forming property. The adsorption of the polar group on the substrate surface enables the copolymer to firmly adhere to the substrate, enhancing the adhesiveness, and the stable molecular structure enhances the resistance of the copolymer to environmental factors, thereby improving the weather resistance of the copolymer.

[0013] Preferably, the initiator includes azobisisobutyronitrile and diphenyliodonium hexafluorophosphate.

[0014] Azobisisobutyronitrile can homolytically generate free radicals under heating conditions, initiating the radical polymerization reaction of organosilicon monomers and acrylamide monomers. Its decomposition temperature is moderate, which can make the reaction start under relatively mild and controllable conditions, gradually connect monomers with different polarities together, and avoid local aggregation or phase separation caused by the polarity difference due to overly violent reaction; diphenyliodonium hexafluorophosphate can generate strongly oxidizing aryl free radicals under light conditions, and has high efficiency in initiating ring-opening polymerization for the epoxy group in β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. Cooperating with azobisisobutyronitrile, it can initiate the polymerization reaction at different stages and levels, making the organosilicon monomers and acrylamide monomers combine more fully with each other; this multi-stage and multi-way initiation effect enables monomers with different polarities to be more evenly distributed and polymerized at the molecular level, effectively reducing the instability problem of the copolymer caused by the polarity difference. The stable copolymer structure helps to improve the film-forming property, adhesiveness and weather resistance.

[0015] Preferably, the mass ratio of azobisisobutyronitrile to diphenyliodonium hexafluorophosphate is 1:(3 - 4).

[0016] The initiator compounded according to the above mass ratio can effectively improve the reaction effect between copolymers, thereby reducing the influence of phase separation on the properties of copolymers, and thus improving film-forming property, adhesiveness and weather resistance.

[0017] Preferably, the crosslinking agent includes pentaerythritol triacrylate.

[0018] Pentaerythritol triacrylate has three highly active acrylate functional groups, which can undergo crosslinking reactions with organosilicon monomers and acrylamide monomers in the polymerization reaction, build a bridge between monomer molecules with different polarities, and make the organosilicon monomers and acrylamide monomers with large polarity differences closely connected by chemical bonds, effectively inhibiting the phase separation phenomenon caused by different polarities and enhancing the stability of the copolymer system; the stable copolymer structure helps the molecules to be arranged orderly, forming a uniform, dense and continuous film layer; at the same time, the crosslinked structure endows the film layer with flexibility and elasticity, enabling it to better adapt to the surfaces of different substrates, and enhancing the adhesiveness between the copolymer and the substrate by increasing the contact area and interaction force between molecules; the crosslinked network structure formed by pentaerythritol triacrylate can protect the copolymer molecules, block the erosion and damage of external environmental factors such as ultraviolet rays, oxygen, moisture, etc. to the molecular chains, and improve the weather resistance of the copolymer.

[0019] In a second aspect, the present application provides a method for preparing an organosilicon acrylamide copolymer, adopting the following technical solution: A method for preparing an organosilicon acrylamide copolymer includes the following steps: (1) Add an organosilicon monomer, an acrylamide monomer and a crosslinking agent to a solvent, stir to obtain a mixture; pass a neutral gas into the mixture to obtain an anaerobic reaction system; (2) Heat the anaerobic reaction system, add an initiator, stir and react, then turn on ultraviolet light, heat and stir to react. After the reaction is completed, cool, add a leveling agent and an antifoaming agent, stir and then screen to obtain an organosilicon acrylamide copolymer.

[0020] The organosilicon acrylamide copolymer prepared according to the above steps can effectively improve the stability of the copolymer through stepwise initiation polymerization, reduce the occurrence of phase separation phenomenon, and the copolymer has good film-forming property, adhesiveness and weather resistance.

[0021] Preferably, in step (2), it is heated to 50 - 60 °C and stirred and reacted at a speed of 200 - 300 rpm for 50 - 70 min.

[0022] Preferably, the ultraviolet reaction conditions in step (2) are: wavelength is 365 nm, light intensity is 5 - 15 mW / cm 2, at a distance of 8 - 12 cm from the container, stir at a speed of 150 - 250 rpm, and react at 50 - 60 °C for 1.5 - 2.5 h.

[0023] The silicone acrylamide copolymer prepared under the above conditions can enable stable copolymerization reactions between different polar monomers, improve the stability of the copolymer, and thus enhance the film-forming property, adhesion, and weather resistance.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. The silicone monomer has a low surface energy, good flexibility, and high and low temperature resistance characteristics. Its molecular structure can endow the molecular chain with a certain degree of freedom of movement in the copolymer system, which helps the orderly arrangement of molecules during the film-forming process and forms a uniform and continuous film layer; the high bond energy of the silicon-oxygen bond enables the copolymer to resist the erosion of the external environment and enhance the weather resistance; the acrylamide monomer contains a polar amide group, which is easy to form hydrogen bonds and other interactions with other substances, and helps the intermolecular attraction and combination during film formation, improving the density and integrity of the film and enhancing the film-forming property; the acrylamide group can form a strong adhesion force with the substrate surface, enhancing the binding between the copolymer and the substrate; the initiator promotes the polymerization reaction between the silicone monomer and the acrylamide monomer to form a chemical bond connection, enabling monomers with different polarities to combine at the molecular level, reducing the phase separation tendency caused by polarity differences, and enhancing the stability of the copolymer; the cross-linking agent forms chemical bonds between the copolymer molecular chains, reduces the phase separation problem caused by polarity differences as a bridge, constructs a three-dimensional network structure, enhances the intermolecular interaction, improves the mechanical strength and stability of the film, and further enhances the film-forming property and adhesion; at the same time, this cross-linked structure can also better resist the damage of the external environment to the copolymer and enhance the weather resistance.

[0025] 2. The dimethylcyclosiloxane mixture has good flexibility and fluidity. The silicon-oxygen bond in its molecular structure endows it with low surface energy characteristics, improves the contact performance of the copolymer with different substrates, and thus enhances the adhesion performance; the silicon-hydrogen bond in methylhydrogen silicone oil gives it active reactivity, and it can undergo cross-linking reactions with other monomers during the polymerization process, enhancing the intermolecular interaction, helping to connect monomers with large polarity differences, and reducing the phase separation trend caused by polarity differences; β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane contains epoxy groups and siloxane groups. The epoxy groups can undergo ring-opening reactions to form chemical bonds with other monomers, increasing the connection points between molecular chains and making the copolymer molecular structure more compact and stable; the siloxane groups further enhance the weather resistance and low surface energy characteristics of the copolymer; these silicone monomers work synergistically, through the interaction and reaction between different groups, effectively reducing the adverse effects of polarity differences on the stability of the copolymer, enhancing the stability of the copolymer, and thus enhancing its film-forming property, adhesion, and weather resistance.

[0026] 3. Azodiisobutyronitrile can homolytically generate free radicals under heating conditions, initiating the free radical polymerization reaction of organosilicon monomers and acrylamide monomers. Its decomposition temperature is moderate, which can start the reaction under relatively mild and controllable conditions, gradually connecting monomers with different polarities together, and avoiding local aggregation or phase separation caused by polarity differences due to overly violent reactions; diphenyliodonium hexafluorophosphate can generate strongly oxidizing aryl free radicals under light conditions, and has high efficiency in initiating ring-opening polymerization for the epoxy groups in β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. When combined with azodiisobutyronitrile, it can initiate the polymerization reaction at different stages and levels, enabling organosilicon monomers and acrylamide monomers to combine more fully with each other; this multi-stage and multi-mode initiation effect allows monomers with different polarities to be more evenly distributed and polymerized at the molecular level, effectively reducing the instability problem of the copolymer caused by polarity differences; the stable copolymer structure helps to improve film-forming properties, adhesion, and weather resistance. Detailed implementation mode

[0027] The embodiments of this application disclose an organosilicon acrylamide copolymer and its preparation method. The raw materials used in this application can be obtained from commercially available raw materials except as otherwise specified. The following further details this application in combination with embodiments: Raw material description: Pentaerythritol triacrylate (CAS No.: 3524-68-3), dimethylcyclosiloxane mixture (CAS No.: 68037-71-8), purchased from Shanghai Haochong Chemical Co., Ltd., methyl hydrogen silicone oil (CAS No.: 63148-57-2), β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (CAS No.: 3388-04-3), N-hydroxymethylacrylamide (CAS No.: 924-42-5), N,N'-divinylbisacrylamide (CAS No.: 2956-58-3), azodiisobutyronitrile (CAS No.: 78-67-1), diphenyliodonium hexafluorophosphate (CAS No.: 58109-40-3), the leveling agent model is BYK-333 of BYK, and the defoaming agent model is SC370 of Wacker.

[0028] Example 1 (1) Add 10 kg of organosilicon monomers, 40 kg of acrylamide monomers, and 3 kg of pentaerythritol triacrylate to 50 kg of toluene. The organosilicon monomers are composed of dimethylcyclosiloxane mixture, methyl hydrogen silicone oil, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane with a mass ratio of 2:1:0.5. The mass ratio of N-hydroxymethylacrylamide and N,N'-divinylbisacrylamide in the acrylamide monomers is 1:1. Stir at a speed of 200 rpm for 30 min to obtain a mixture; pass nitrogen into the mixture for 30 min to obtain an anaerobic reaction system; (2) Heat the anaerobic reaction system to 50 °C, add 0.5 kg of initiator, which consists of 0.125 kg of azobisisobutyronitrile and 0.375 kg of diphenyliodonium hexafluorophosphate. After stirring the reaction at a speed of 200 rpm for 70 min, turn on the ultraviolet lamp for irradiation reaction. The wavelength is 365 nm, the light intensity is 5 mW / cm 2 , at a distance of 8 cm from the container, under the condition of top irradiation, stir at a speed of 150 rpm, and react at 50 °C for 2.5 h. After the reaction is completed, cool it to below 30 °C, add 0.5 kg of leveling agent and 0.3 kg of defoaming agent, stir at a speed of 200 rpm for 30 min, and pass through a 100-mesh sieve to obtain the organosilicon acrylamide copolymer.

[0029] Example 2 (1) Add 20 kg of organosilicon monomer, 50 kg of acrylamide monomer and 5 kg of pentaerythritol triacrylate to 70 kg of toluene. The organosilicon monomer consists of a dimethylcyclosiloxane mixture, methylhydrogen silicone oil and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane with a mass ratio of 2:1:1.5. The mass ratio of N-methylolacrylamide and N,N'-vinylbisacrylamide in the acrylamide monomer is 1:1. Stir at a speed of 200 rpm for 30 min to obtain a mixture; pass nitrogen through the mixture for 30 min to obtain an anaerobic reaction system; (2) Heat the anaerobic reaction system to 60 °C, add 1.5 kg of initiator, which consists of 0.3 kg of azobisisobutyronitrile and 1.2 kg of diphenyliodonium hexafluorophosphate. After stirring the reaction at a speed of 300 rpm for 50 min, turn on the ultraviolet lamp for irradiation reaction. The wavelength is 365 nm, the light intensity is 15 mW / cm 2 , at a distance of 12 cm from the container, under the condition of top irradiation, stir at a speed of 250 rpm, and react at 60 °C for 1.5 h. After the reaction is completed, cool it to below 30 °C, add 1.5 kg of leveling agent and 0.5 kg of defoaming agent, stir at a speed of 200 rpm for 30 min, and pass through a 100-mesh sieve to obtain the organosilicon acrylamide copolymer.

[0030] Example 3 (1) Add 15 kg of organosilicon monomer, 45 kg of acrylamide monomer and 4 kg of pentaerythritol triacrylate to 60 kg of toluene. The organosilicon monomer consists of a dimethylcyclosiloxane mixture, methylhydrogen silicone oil and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane with a mass ratio of 2:1:1. The mass ratio of N-methylolacrylamide and N,N'-vinylbisacrylamide in the acrylamide monomer is 1:1. Stir at a speed of 200 rpm for 30 min to obtain a mixture; pass nitrogen through the mixture for 30 min to obtain an anaerobic reaction system; (2) Heat the anaerobic reaction system to 55°C, add 1 kg of initiator. The initiator consists of 0.22 kg of azobisisobutyronitrile and 0.78 kg of diphenyliodonium hexafluorophosphate. Stir the reaction at a speed of 250 rpm for 60 min, then turn on the ultraviolet lamp for irradiation. The wavelength is 365 nm and the light intensity is 10 mW / cm 2 , at a distance of 10 cm from the container, under the condition of top irradiation, stir at a speed of 200 rpm, react at 55°C for 2 h. After the reaction is completed, cool it to below 30°C, add 1 kg of leveling agent and 0.4 kg of defoaming agent, stir at a speed of 200 rpm for 30 min, and pass through a 100-mesh sieve to obtain the organosilicon acrylamide copolymer.

[0031] Example 4 Example 4 is based on Example 3. The difference between Example 4 and Example 3 is only that in Example 4, the organosilicon monomer consists of a dimethylcyclosiloxane mixture and methylhydrogen silicone oil with a mass ratio of 2:1.

[0032] Example 5 Example 5 is based on Example 3. The difference between Example 5 and Example 3 is only that in Example 5, the organosilicon monomer consists of a dimethylcyclosiloxane mixture, methylhydrogen silicone oil and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane with a mass ratio of 2:1:2.

[0033] Example 6 Example 6 is based on Example 3. The difference between Example 6 and Example 3 is only that in Example 6, the acrylamide monomer is N-hydroxymethylacrylamide.

[0034] Example 7 Example 7 is based on Example 3. The difference between Example 7 and Example 3 is only that in Example 7, the acrylamide monomer is N,N'-vinylbisacrylamide.

[0035] Example 8 Example 8 is based on Example 3. The difference between Example 8 and Example 3 is only that in Example 8, the dosage of azobisisobutyronitrile is 0.33 kg and the dosage of diphenyliodonium hexafluorophosphate is 0.67 kg.

[0036] Example 9 Example 9 is based on Example 3. The difference between Example 9 and Example 3 is only that in Example 9, the dosage of azobisisobutyronitrile is 0.17 kg and the dosage of diphenyliodonium hexafluorophosphate is 0.83 kg.

[0037] Example 10 Example 10 is based on Example 3. The difference between Example 10 and Example 3 is only that in step (2) of Example 10, the reaction conditions are to heat the anaerobic reaction system to 45°C, stir the reaction at a speed of 150 rpm for 80 min, then turn on the ultraviolet lamp for irradiation reaction, with a wavelength of 365 nm and a light intensity of 5 mW / cm 2 , at a distance of 5 cm from the container, under the condition of top irradiation, stir at a speed of 100 rpm, and react at 45°C for 3 h.

[0038] Example 11 Example 11 is based on Example 3. The difference between Example 11 and Example 3 is only that in step (2) of Example 11, the reaction conditions are to heat the anaerobic reaction system to 65°C, stir the reaction at a speed of 350 rpm for 40 min, then turn on the ultraviolet lamp for irradiation reaction, with a wavelength of 365 nm and a light intensity of 15 mW / cm 2 , at a distance of 10 cm from the container, under the condition of top irradiation, stir at a speed of 300 rpm, and react at 65°C for 1 h.

[0039] Comparative Example 1 Comparative Example 1 is based on Example 3. The difference between Comparative Example 1 and Example 3 is only that in Comparative Example 1, a photoinitiator is not used as the initiator.

[0040] (1) Add 15 kg of organosilicon monomer, 45 kg of acrylamide monomer, and 4 kg of pentaerythritol triacrylate to 60 kg of toluene. The organosilicon monomer is composed of a dimethylcyclosiloxane mixture, methylhydrogen silicone oil, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane with a mass ratio of 2:1:1. The mass ratio of N-hydroxymethylacrylamide and N,N'-vinylbisacrylamide in the acrylamide monomer is 1:1. Stir at a speed of 200 rpm for 30 min to obtain a mixed material; pass nitrogen through the mixed material for 30 min to obtain an anaerobic reaction system; (2) Heat the anaerobic reaction system to 55°C, add 1 kg of azobisisobutyronitrile, stir the reaction at a speed of 250 rpm for 4 h. After the reaction is completed, cool it to below 30°C, add 1 kg of leveling agent and 0.4 kg of defoaming agent, stir at a speed of 200 rpm for 30 min, and pass through a 100-mesh sieve to obtain an organosilicon acrylamide copolymer.

[0041] Performance Detection Test (1) Select "GB / T 9754-2007 Determination of 20°, 60° and 85° Specular Gloss of Paints and Varnishes - Paints Without Metallic Pigments" as the standard. Uniformly coat the specimen on a flat and clean black glass plate, dry it for 24 h in an environment with a temperature of 23°C and a relative humidity of 50%. Select a measurement angle of 60°, test the glossiness, calculate the average value, and record the results in Table 1.

[0042] (2) Select "GB / T 5210-2006 Paints and varnishes - Pull-off adhesion test" as the standard to test the adhesion strength of the specimens. Each specimen is tested three times, and the average value is taken after measurement. The results are recorded in Table 1.

[0043] (3) Select "GB / T 16422.3-2022 Plastics - Methods of exposure to laboratory light sources - Part 3: Fluorescent UV lamps" as the standard. Age the specimens under ultraviolet light conditions for 1000 hours, test the glossiness of the specimens before and after ultraviolet aging, calculate the retention rate. Each specimen is tested three times, and the average value is taken after measurement. The results are recorded in Table 1.

[0044] Table 1 Detection results of film-forming property, adhesion property and weather resistance of silicone acrylamide copolymer Test Results Glossiness (GU) Adhesion Strength (MPa) Gloss Retention Rate after UV (%) Example 1 85.3 4.3 82.6 Example 2 87.6 3.7 84.3 Example 3 86.8 4.2 83.8 Example 4 84.1 3.5 81.5 Example 5 87.0 3.3 84.2 Example 6 84.5 4.1 81.0 Example 7 85.2 3.5 82.1 Example 8 84.3 3.6 82.4 Example 9 83.2 3.5 81.7 Example 10 82.4 3.1 80.6 Example 11 82.7 3.3 81.2 Comparative Example 1 80.5 2.9 78.3 As can be seen from Table 1, the glossiness of Examples 1-3 is greater than 85.3 GU, the adhesion strength is greater than 3.7 MPa, and the gloss retention rate after ultraviolet is greater than 82.6%. Thus, it can be seen that the silicone acrylamide copolymer prepared in this application has good film-forming property, adhesion property and weather resistance.

[0045] As can be seen from Table 1, the differences between Examples 4 and 5 and Example 3 are only as follows: in Example 4, the silicone monomer consists of a dimethylcyclosiloxane mixture and methylhydrogen silicone oil with a mass ratio of 2:1; in Example 5, the silicone monomer consists of a dimethylcyclosiloxane mixture, methylhydrogen silicone oil and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane with a mass ratio of 2:1:2. Compared with Example 3, the performance of Examples 4 and 5 decreases. This is because if epoxy group silane is not added, the promotion effect on interface compatibility is lacking, the tendency of phase separation increases, the surface roughness increases, the glossiness decreases, the hydrogen bond effect weakens, and the stability of the cross-linked network decreases; if the dosage of epoxy group silane is increased, although the interface combination and cross-linking uniformity can be further enhanced, the rigidity of the material increases and the adhesion performance decreases.

[0046] As can be seen from Table 1, the differences between Examples 6 and 7 and Example 3 are only as follows: in Example 6, the acrylamide monomer is N-hydroxymethylacrylamide; in Example 7, the acrylamide monomer is N,N'-vinylbisacrylamide. Compared with Example 3, the performance of Examples 6 and 7 decreases. This is because reducing the components of the acrylamide monomer will affect the improvement of stability by their combined action, and the structural stability between molecules decreases, thus affecting the film-forming property, adhesion property and weather resistance.

[0047] As can be seen from Table 1, the differences between Examples 8 and 9 and Example 3 are only as follows: in Example 8, the mass ratio of azobisisobutyronitrile to diphenyliodonium hexafluorophosphate is 1:2; in Example 9, the mass ratio of azobisisobutyronitrile to diphenyliodonium hexafluorophosphate is 1:5. Compared with Example 3, the performance of Examples 8 and 9 has decreased. This is because changing the proportion of components in the initiator will affect the process and effect of the stepwise initiation polymerization reaction, and further affect the stability of monomer polymerization, resulting in an increase in the influence of polarity on the reaction, thus causing a decrease in performance.

[0048] As can be seen from Table 1, the differences between Examples 10 and 11 and Example 3 are only as follows: in Examples 10 and 11, the polymerization reaction conditions are regulated. Compared with Example 3, the performance of Examples 10 and 11 has decreased. This is because destroying the reaction conditions within the optimal range will increase the difficulty of the polymerization reaction between different polar monomers, resulting in a decrease in the stability of the copolymer, and further affecting its film-forming property, adhesion, and weather resistance.

[0049] As can be seen from Table 1, the difference between Comparative Example 1 and Example 3 is only as follows: in Comparative Example 1, no photoinitiator is used as the initiator. Compared with Example 3, the performance of Comparative Example 1 has decreased. This is because only using azobisisobutyronitrile for free radical polymerization has a slow reaction rate and poor crosslinking uniformity. After extending the reaction time, local pre-crosslinking will occur, leading to phase separation problems, thus significantly decreasing the performance.

[0050] This specific embodiment is only an interpretation of the present application and does not limit the present application. Through the above description, relevant staff can make various changes and modifications completely within the scope without departing from the technical idea of this application. The technical scope of this application is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A silicone acrylamide copolymer, characterized in that: It comprises components in the following parts by mass: 10 - 20 parts of silicone monomer 40 - 50 parts of acrylamide monomer 0.5 - 1.5 parts of initiator 3 - 5 parts of crosslinking agent 50 - 70 parts of solvent 0.5 - 1.5 parts of leveling agent 0.3 - 0.5 parts of defoaming agent.

2. The organosilicon acrylamide copolymer according to claim 1, wherein: The silicone monomer includes dimethylcyclosiloxane mixture, methylhydrogen silicone oil and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

3. An organosilicon acrylamide copolymer according to claim 2, characterized in that: The mass ratio of the dimethylcyclosiloxane mixture, methylhydrogen silicone oil and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane is 2:1:(0.5 - 1.5).

4. An organosilicon acrylamide copolymer according to claim 1, wherein: The acrylamide monomer includes N-hydroxymethylacrylamide and N,N'-vinylbisacrylamide.

5. An organosilicon acrylamide copolymer according to claim 1, characterized in that: The initiator includes azobisisobutyronitrile and diphenyliodonium hexafluorophosphate.

6. The organosilicon acrylamide copolymer according to claim 5, characterized in that: The mass ratio of the azobisisobutyronitrile and diphenyliodonium hexafluorophosphate is 1:(3 - 4).

7. An organosilicon acrylamide copolymer according to claim 1, wherein: The crosslinking agent includes pentaerythritol triacrylate.

8. A preparation method applied to the organosilicon acrylamide copolymer as described in any one of claims 1-7, characterized in that: It includes the following steps: (1) Add the silicone monomer, acrylamide monomer and crosslinking agent into the solvent, stir to obtain a mixture; pass neutral gas into the mixture to obtain an anaerobic reaction system; (2) Heat up the anaerobic reaction system, add the initiator, stir and react, then turn on the ultraviolet light, heat and stir to react. After the reaction is completed, cool, add the leveling agent and defoaming agent, stir and then screen to obtain the silicone acrylamide copolymer.

9. The preparation method of the silicone acrylamide copolymer according to claim 8, characterized in that: In the step (2), it is heated up to 50 - 60 °C and stirred and reacted at a speed of 200 - 300 rpm for 50 - 70 min.

10. The preparation method of the silicone acrylamide copolymer according to claim 8, characterized in that: The UV reaction conditions in step (2) are as follows: the wavelength is 365 nm, the light intensity is 5-15 mW / cm 2 , the distance from the container is 8-12 cm, stirring is carried out at a speed of 150-250 rpm, and the reaction is carried out at 50-60 °C for 1.5-2.5 h.