Organic silicon modified phenolic resin and preparation method of coating thereof
By using a method to prepare organosilicon-modified phenolic resin, the problems of insufficient antifouling performance and limited heat resistance of traditional phenolic resin coatings in marine environments have been solved. This method improves the coating's antimicrobial adhesion and high-temperature resistance, making it suitable for the protection of metal components.
Patent Information
- Application Number
- CN202511272507.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-08
- Publication Date
- 2025-12-16
AI Technical Summary
Traditional phenolic resin coatings have insufficient antifouling performance and limited heat stability in marine environments, and cannot effectively prevent microbial adhesion or withstand temperature fluctuations.
The preparation method of organosilicon modified phenolic resin involves introducing curcumin, paraformaldehyde or formaldehyde and organosilicon compounds, combined with a silane coupling agent containing a primary amine group, to form a modified benzoxazine monomer, which is then heated and cured on the substrate surface to form a coating.
It significantly improves the coating's resistance to microbial adhesion and high-temperature stability, enhances its corrosion resistance, and is suitable for protecting ship metal components in harsh marine environments.
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Figure CN121135993A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the field of metal corrosion and biofouling prevention, in particular to the field of resins, and more particularly to a kind of organosilicon modified phenolic resin and the preparation method of its coating. BACKGROUND
[0002] Metal corrosion and biofouling are common problems of marine ship components during use. In the high-salinity and high-humidity seawater environment, metal materials are prone to electrochemical corrosion, leading to reduced structural performance. Microorganisms (including bacteria and algae) can attach to the metal surface and form biofilms, which can induce localized corrosion and exacerbate metal damage, forming a cycle of mutual promotion of corrosion and biofouling, affecting the service life and safety of ship components.
[0003] Phenolic resin is applied in the field of protective coating due to its certain mechanical properties, corrosion resistance and adhesion. However, existing studies have shown that the anti-fouling performance of traditional phenolic resin coating in marine environment is limited, and it is easily affected by microbial attachment, leading to a decline in protective effect. At the same time, during the long-term service of the ship, high temperature or temperature fluctuation may occur, and the heat resistance and stability of the traditional phenolic resin coating are insufficient, which also limits its application effect in complex environment. SUMMARY
[0004] To solve the problems of insufficient anti-fouling performance and limited heat resistance and stability of traditional phenolic resin coating in the background art, the present disclosure provides a kind of organosilicon modified phenolic resin and the preparation method of its coating.
[0005] The organosilicon modified phenolic resin provided by the present disclosure comprises curcumin, paraformaldehyde or formaldehyde and an organosilicon compound; the organosilicon compound comprises at least one of polydimethylsiloxane, polymethylhydrosiloxane, polyethylmethylsiloxane, polyphenylmethylsiloxane and epoxysiloxane.
[0006] In some embodiments, the raw materials further comprise a silane coupling agent containing a primary amine group, preferably γ-aminopropyl triethoxysilane.
[0007] In some embodiments, the molar ratio of curcumin, paraformaldehyde or formaldehyde, silane coupling agent containing primary amine group and organosilicon compound is (0.01-20) : (0.02-20) : (0.01-20) :
[0008] (0.01-20).
[0009] The preparation method of the organosilicon modified phenolic resin coating provided by the present disclosure comprises the following steps:
[0010] Step S1, reacting raw materials curcumin, paraformaldehyde or formaldehyde and an organic silicon compound in an organic solvent to obtain a modified benzoxazine monomer, and then filtering; wherein the organic silicon compound includes at least one of polydimethylsiloxane, polymethylhydrosiloxane, polyethylmethylsiloxane, polyphenylmethylsiloxane, and epoxysiloxane;
[0011] Step S2, rotary evaporation of the filtered solution to remove excess organic solvent, and then dissolving the modified benzoxazine monomer in an organic solvent to obtain a first solution;
[0012] Step S3, rotary evaporation of the first solution to remove excess organic solvent, and then applying to the surface of the substrate;
[0013] Step S4, heating and curing the surface of the substrate treated in step S3 to form a silicone-modified phenolic resin coating.
[0014] In some embodiments, the raw materials further include a silane coupling agent containing a primary amine group, preferably γ-aminopropyl triethoxysilane.
[0015] In some embodiments, the substrate includes at least one of a metal substrate, a glass substrate, a ceramic substrate, an enamel substrate, a polymer substrate, and a composite substrate formed by the above substrates.
[0016] In some embodiments, in step S4, the heating and curing temperature is 10-300°C, and the heating and curing time is 0.1-120h.
[0017] In some embodiments, in step S4, the reaction conditions are: heating temperature is 50-150°C, and curing reaction time is 4-24h.
[0018] In some embodiments, the molar ratio of curcumin, paraformaldehyde, silane coupling agent containing a primary amine group, and organic silicon compound is (0.01-20):(0.02-20):(0.01-20):(0.01-20).
[0019] The present disclosure has the following beneficial effects: by introducing organic silicon into the phenolic resin system, not only the surface energy of the coating is significantly reduced, the anti-microbial adhesion ability is improved, but also the high-temperature stability of the coating is enhanced, and the high mechanical strength and corrosion resistance of the phenolic resin are maintained. The prepared coating exhibits excellent corrosion resistance, antifouling and high-temperature resistance in harsh marine environments such as high temperature, high salt and high humidity, can effectively protect the long-term service life of ship metal components, and realizes comprehensive protection effect. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 The infrared spectra of the coating samples obtained in Examples 1-4; wherein curves A-D represent Examples 1-4, respectively.
[0021] Figure 2 The bar chart shows the adhesion values of the coating samples obtained in Examples 1-4; where A and D represent Examples 1-4, respectively.
[0022] Figure 3 The thermogravimetric analysis (TGA) curves of the coating samples obtained in Examples 1-4 are shown; where curves A and D represent Examples 1-4, respectively.
[0023] Figure 4 This is a bar chart showing the adhesion strength of the products obtained from existing literature (https: / / doi.org / 10.1016 / j.porgcoat.2022.107319Received 10 July 2022; Received in revised form 23); where "Tensile Strength" represents adhesion strength, "Elongation at break" represents elongation at break, and "Sample" represents the sample name.
[0024] Figure 5 The impedance modulus curves of the coating samples obtained in Examples 1-4 are shown; where AD represents Examples 1-4 respectively, and d0, d14, d35, and d63 represent 0 days (when preparation is completed), 14 days, 35 days, and 63 days respectively.
[0025] Figure 6 The Nyquist plots are for the coating samples obtained in Examples 1-4, where AD represent Examples 1-4 respectively, and d0, d14, d35, and d63 represent 0 days (when preparation is complete), 14 days, 35 days, and 63 days respectively.
[0026] Figure 7 The figures show the antibacterial (antibacterial and anti-pseudomonas) adhesion test results of the coating samples obtained in Examples 1-4; where A and D represent Examples 1-4 respectively. Detailed Implementation
[0027] It should be understood that the disclosed embodiments are merely examples of this disclosure, and this disclosure can be implemented in various forms. Therefore, the specific details of this disclosure should not be construed as limiting, but rather serve as the basis for the claims, to teach those skilled in the art how to implement this disclosure in various ways. In the description of this disclosure, terms and technical terms not explicitly stated are common knowledge to those skilled in the art, and methods not explicitly stated are conventional methods known to those skilled in the art.
[0028] The endpoints and any values of the ranges disclosed in this disclosure are not limited to the precise ranges or values, and such ranges or values should be understood to include values close to such ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed herein.
[0029] [Organosilicon-modified phenolic resin]
[0030] Compared to traditional epoxy and phenolic resins, benzoxazine resins possess numerous superior properties, including low water absorption, high modulus, high thermal stability, and high cost-effectiveness. However, their high curing temperature (approximately 250°C), high processing costs, and complex molding processes limit their application range. This disclosure improves the stain resistance of phenolic resins, including benzoxazine resins, by modifying them with organosilicones such as PDMS, thereby expanding their application scope.
[0031] The organosilicon-modified phenolic resin disclosed herein uses raw materials including curcumin, paraformaldehyde or formaldehyde, and organosilicon compounds; the organosilicon compounds include at least one of polydimethylsiloxane, polymethylhydrosiloxane, polyethylmethylsiloxane, polyphenylmethylsiloxane, and epoxysiloxane.
[0032] In some embodiments, the raw materials further include a silane coupling agent containing a primary amine group, preferably γ-aminopropyltriethoxysilane. Adding a silane coupling agent containing a primary amine group to the raw materials can make the modified resin chemical structure more complete and its performance more stable. In some embodiments, the structure of benzoxazine includes curcumin, paraformaldehyde, and a primary amine group; organosilicon-modified phenolic resin compounds are achieved by introducing organosilicon compounds into the positions of the primary amine groups.
[0033] In some embodiments, the molar ratio of curcumin, paraformaldehyde or formaldehyde, silane coupling agent containing primary amine groups, and organosilicon compound is (0.01–20):(0.02–20):(0.01–20):(0.01–20).
[0034] [Preparation method of organosilicon-modified phenolic resin coating]
[0035] The preparation of organosilicon-modified phenolic resin coatings can be achieved by reacting benzoxazine with organosilicon compounds in an organic solvent, and then separating the reaction products to obtain polymers with different cross-linking structures, thereby improving the anti-fouling properties.
[0036] In some embodiments, a method for preparing an organosilicon-modified phenolic resin coating includes the following steps: Step S1, reacting raw materials curcumin, paraformaldehyde or formaldehyde, and an organosilicon compound in an organic solvent to obtain a modified benzoxazine monomer, and then filtering; wherein the organosilicon compound includes at least one of polydimethylsiloxane, polymethylhydrosiloxane, polyethylmethylsiloxane, polyphenylmethylsiloxane, and epoxysiloxane; Step S2, rotary evaporating the filtered solution to remove excess organic solvent, and then dissolving the modified benzoxazine monomer in the organic solvent to obtain a first solution; Step S3, rotary evaporating the first solution to remove excess organic solvent, and applying it to the substrate surface; Step S4, heating and curing the substrate surface treated in Step S3 to form an organosilicon-modified phenolic resin coating.
[0037] In some embodiments, the raw materials further include a silane coupling agent containing a primary amine group, preferably γ-aminopropyltriethoxysilane. Adding a silane coupling agent containing a primary amine group to the raw materials can make the modified resin have a more complete chemical structure and more stable properties.
[0038] In some embodiments, the substrate includes at least one of a metal substrate, a glass substrate, a ceramic substrate, an enamel substrate, a polymer substrate, and a composite substrate formed from the above substrates.
[0039] In some embodiments, in step S4, the temperature for heating and curing is 10°C to 300°C, and the heating and curing time is 0.1h to 120h.
[0040] In some embodiments, in step S4, the reaction conditions are: heating temperature of 50°C to 150°C, and curing reaction time of 4h to 24h.
[0041] In some embodiments, the molar ratio of curcumin, paraformaldehyde, silane coupling agent containing primary amine groups, and organosilicon compound is (0.01–20):(0.02–20):(0.01–20):(0.01–20).
[0042] [Example]
[0043] The present disclosure is further illustrated below with reference to the embodiments. Unless otherwise specified, the reagents, materials and instruments used in the following embodiments and comparative examples are commercially available or prepared by methods known in the art.
[0044] Example 1
[0045] Weigh curcumin (0.010 mol, 3.68 g) and paraformaldehyde (0.040 mol, 1.220 g) into a 250 mL three-necked flask. Add γ-aminopropyltriethoxysilane (0.013 mol, 2.947 g), amino-terminated PDMS (0.010 mol, 3.333 g), and 60 mL of tetrahydrofuran. Incubate the reaction in an oil bath at 80 °C for 8 h. After the reaction is complete, filter the resulting mixture and remove excess organic solvent by rotary evaporation. Benzoxazine monomer was obtained, and then the modified benzoxazine monomer was dissolved in an organic solvent to obtain a first solution. The excess organic solvent was removed by rotary evaporation of the first solution, and then spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40℃ for 20 min, then curing at 60℃ for 20 min, then curing at 80℃ for 20 min, then curing at 100℃ for 20 min, and finally curing at 120℃ for 1.5 h to obtain PDMS modified benzoxazine coating A.
[0046] Example 2
[0047] Weigh curcumin (0.010 mol, 3.680 g) and paraformaldehyde (0.040 mol, 1.220 g) into a 250 mL three-necked flask. Add γ-aminopropyltriethoxysilane (0.007 mol, 1.473 g), amino-terminated PDMS (0.013 mol, 6.667 g), and 60 mL of tetrahydrofuran. React in an oil bath at 80 °C for 8 h. After the reaction is complete, filter the resulting mixture and remove excess organic solvent by rotary evaporation. The benzoxazine monomer was obtained, and then the modified benzoxazine monomer was dissolved in an organic solvent to obtain a first solution. The excess organic solvent was removed by rotary evaporation of the first solution, and then spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40℃ for 20 min, then curing at 60℃ for 20 min, then curing at 80℃ for 20 min, then curing at 100℃ for 20 min, and finally curing at 120℃ for 1.5 h to obtain PDMS modified benzoxazine coating B.
[0048] Example 3
[0049] Curcumin (0.010 mol, 3.680 g) and paraformaldehyde (0.040 mol, 1.220 g) were weighed into a 250 mL three-necked flask. Amino-terminated PDMS (0.020 mol, 10.000 g) and 60 mL of tetrahydrofuran were added. The reaction was carried out in an oil bath at 80 °C for 8 h. After the reaction was completed, the resulting mixture was filtered, and excess organic solvent was removed by rotary evaporation to obtain benzoxazine monomer. The modified benzoxazine monomer was then dissolved in an organic solvent to obtain the first solution. Excess organic solvent was removed by rotary evaporation of the first solution, and the solution was spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40 °C for 20 min, then at 60 °C for 20 min, then at 80 °C for 20 min, then at 100 °C for 20 min, and finally at 120 °C for 1.5 h to obtain PDMS modified benzoxazine coating C.
[0050] Example 4
[0051] Weigh curcumin (0.010 mol, 3.680 g) and paraformaldehyde (0.04 mol, 1.220 g) into a 250 mL three-necked flask. Add γ-aminopropyltriethoxysilane (0.010 mol, 2.210 g), amino-terminated PDMS (0.010 mol, 5.000 g), and 60 mL of tetrahydrofuran. Incubate the reaction in an oil bath at 80 °C for 8 h. After the reaction is complete, filter the resulting mixture and remove excess organic solvent by rotary evaporation. Benzoxazine monomer was obtained, and then the modified benzoxazine monomer was dissolved in an organic solvent to obtain a first solution. The excess organic solvent was removed by rotary evaporation of the first solution, and then spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40℃ for 20 min, then curing at 60℃ for 20 min, then curing at 80℃ for 20 min, then curing at 100℃ for 20 min, and finally curing at 120℃ for 1.5 h to obtain PDMS modified benzoxazine coating D.
[0052] Example 5
[0053] Weigh curcumin (0.010 mol, 3.680 g) and paraformaldehyde (0.040 mol, 1.220 g) into a 250 mL three-necked flask. Add γ-aminopropyltriethoxysilane (0.026 mol, 2.210 g), amino-terminated PDMS (0.005 mol, 1.667 g), and 60 mL of tetrahydrofuran. React in an oil bath at 80 °C for 8 h. After the reaction is complete, filter the resulting mixture and remove excess organic solvent by rotary evaporation. The benzoxazine monomer was obtained, and then the modified benzoxazine monomer was dissolved in an organic solvent to obtain a first solution. The excess organic solvent was removed by rotary evaporation of the first solution, and then spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40℃ for 20 min, then curing at 60℃ for 20 min, then curing at 80℃ for 20 min, then curing at 100℃ for 20 min, and finally curing at 120℃ for 1.5 h to obtain PDMS modified benzoxazine coating E.
[0054] Example 6
[0055] Curcumin (0.010 mol, 3.680 g) and paraformaldehyde (0.040 mol, 1.220 g) were weighed into a 250 mL three-necked flask. γ-aminopropyltriethoxysilane (0.020 mol, 4.420 g) and 60 mL of tetrahydrofuran were added. The reaction was carried out in an oil bath at 80 °C for 8 h. After the reaction was complete, the resulting mixture was filtered, and excess organic solvent was removed by rotary evaporation to obtain the benzoxazine monomer. Then, the modified... After oxidation, the benzoxazine monomer is dissolved in an organic solvent to obtain a first solution. The excess organic solvent in the first solution is removed by rotary evaporation, and the solution is then spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process is as follows: first, curing at 40℃ for 20 min, then at 60℃ for 20 min, then at 80℃ for 20 min, then at 100℃ for 20 min, and finally at 120℃ for 1.5 h to obtain PDMS modified benzoxazine coating F.
[0056] Example 7
[0057] Weigh curcumin (0.010 mol, 3.680 g) and paraformaldehyde (0.040 mol, 1.220 g) into a 250 mL three-necked flask. Add γ-aminopropyltriethoxysilane (0.004 mol, 0.737 g), amino-terminated PDMS (0.026 mol, 13.334 g), and 60 mL of tetrahydrofuran. React in an oil bath at 80 °C for 8 h. After the reaction is complete, filter the resulting mixture and remove excess organic solvent by rotary evaporation. The benzoxazine monomer was obtained, and then the modified benzoxazine monomer was dissolved in an organic solvent to obtain a first solution. The excess organic solvent was removed by rotary evaporation of the first solution, and then spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40℃ for 20 min, then curing at 60℃ for 20 min, then curing at 80℃ for 20 min, then curing at 100℃ for 20 min, and finally curing at 120℃ for 1.5 h to obtain PDMS modified benzoxazine coating G.
[0058] Example 8
[0059] Curcumin (0.010 mol, 3.680 g) and paraformaldehyde (0.040 mol, 1.220 g) were weighed into a 250 mL three-necked flask. γ-aminopropyltriethoxysilane (0.040 mol, 8.840 g) and 60 mL of tetrahydrofuran were added. The reaction was carried out in an oil bath at 80 °C for 8 h. After the reaction was complete, the resulting mixture was filtered, and excess organic solvent was removed by rotary evaporation to obtain the benzoxazine monomer. Then, the modified... After oxidation, the benzoxazine monomer is dissolved in an organic solvent to obtain a first solution. The excess organic solvent in the first solution is removed by rotary evaporation, and the solution is then spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process is as follows: first, curing at 40℃ for 20 min, then at 60℃ for 20 min, then at 80℃ for 20 min, then at 100℃ for 20 min, and finally at 120℃ for 1.5 h to obtain the PDMS modified benzoxazine coating H.
[0060] Example 9
[0061] Curcumin (0.050 mol, 18.400 g) and paraformaldehyde (0.200 mol, 6.100 g) were weighed into a 250 mL three-necked flask. γ-aminopropyltriethoxysilane (0.050 mol, 11.050 g) and 60 mL of tetrahydrofuran were added, and the reaction was carried out in an oil bath at 80 °C for 8 h. After the reaction was completed, the resulting mixture was filtered, and excess organic solvent was removed by rotary evaporation to obtain benzoxazine monomer. Then, it was spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40 °C for 20 min, then at 60 °C for 20 min, then at 80 °C for 20 min, then at 100 °C for 20 min, and finally at 120 °C for 1.5 h to obtain PDMS modified benzoxazine coating I.
[0062] Example 10
[0063] Curcumin (0.020 mol, 7.360 g) and paraformaldehyde (0.080 mol, 2.440 g) were weighed into a 250 mL three-necked flask. Amino-terminated PDMS (0.020 mol, 10.000 g) and 60 mL of tetrahydrofuran were added. The reaction was carried out in an oil bath at 80 °C for 8 h. After the reaction was completed, the resulting mixture was filtered, and excess organic solvent was removed by rotary evaporation to obtain benzoxazine monomer. Then, it was spin-coated onto a clean glass slide or carbon steel surface for curing. The curing process was as follows: first, curing at 40 °C for 20 min, then at 60 °C for 20 min, then at 80 °C for 20 min, then at 100 °C for 20 min, and finally at 120 °C for 1.5 h to obtain PDMS modified benzoxazine coating J.
[0064] The material parameters involved in the experiments of Examples 1-10 are shown in Table 1. For ease of explanation, symbols are used to represent substances in Table 1:
[0065] A1: Curcumin;
[0066] A2: Paraformaldehyde;
[0067] A3: γ-aminopropyltriethoxysilane;
[0068] A4: Amino-terminated PDMS.
[0069] Next, infrared testing, mechanical testing, corrosion resistance testing, and antibacterial adhesion testing were conducted on the relevant samples obtained in the above embodiments.
[0070] 1. Infrared Testing: The absorbance of the PDMS-modified benzoxazine resin coating samples obtained in the examples was measured using a Fourier Transform Infrared Spectrometer (FT-IR) (IS-50). The scanning results for Examples 1-4 are shown below. Figure 1 As shown.
[0071] 2. Mechanical Testing: Adhesion tests were conducted on the PDMS-modified benzoxazine resin coating samples obtained in the examples. The test method was to use a PosiTest AT pull-out tester. The adhesion test results of Examples 1-4 are as follows: Figure 2 As shown.
[0072] 3. Thermogravimetric Analysis (TG): The PDMS-modified benzoxazine resin coating samples obtained in the examples were subjected to thermal stability testing. The test method was to use a thermogravimetric analyzer (TGA, model can be specified, such as TA Instruments Q500) under a nitrogen protective atmosphere. The test conditions were a heating rate of 10℃ / min, from room temperature to 800℃, while recording the mass change of the sample. The thermogravimetric curves (TG) and their derived curves (DTG) of Examples 1-4 are shown below. Figure 3 As shown, this was used to evaluate the differences in thermal decomposition temperature and thermal stability of different modified coatings.
[0073] 4. Corrosion Resistance Test: Electrochemical corrosion performance tests were conducted on the PDMS-modified benzoxazine resin coating samples obtained in the examples and blank carbon steel. The electrochemical tests used a three-electrode environment with an Ag / AgCl electrode as the reference electrode, a platinum electrode as the auxiliary electrode, and the sample as the working electrode. A 3.5 wt% NaCl solution was used as the test solvent. Electrochemical corrosion performance was tested on day 0 (when preparation was complete), day 14, day 35, and day 63. The impedance modulus test results of Examples 1-4 are as follows: Figure 5 As shown, the Nyquist test results of electrochemical impedance spectroscopy are as follows: Figure 6 As shown.
[0074] 5. Antibacterial Adhesion Test: First, glass slides containing blank substrates and samples coated with modified resin were mounted in well plates. Then, culture media containing Bacillus and Pseudomonas were added, respectively. The well plates were then shaken on a shaker at 0–200 rpm for 24–48 hours to simulate bacterial adhesion in a liquid environment. After the experiment, the bacterial adhesion on the glass slide surface was observed and analyzed using a laser scanning microscope to evaluate the anti-adhesion performance of the coating. The test results of Examples 1–4 are as follows: Figure 7 As shown.
[0075] Table 1. Material parameters involved in the experiments of Examples 1-10
[0076] Example number A1 / g A2 / g A3 / g A4 / g Example 1 3.680 1.220 2.947 3.333 Example 2 3.680 1.220 1.473 6.667 Example 3 3.680 1.220 - 10.000 Example 4 3.680 1.220 2.210 5.000 Example 5 3.680 1.220 5.894 1.667 Example 6 3.680 1.220 4.42 - Example 7 3.680 1.220 0.737 13.334 Example 8 3.680 1.220 8.84 - Example 9 18.40 6.100 11.050 - Example 10 7.360 2.440 - 10.000
[0077] Note: - indicates no addition.
[0078] Depend on Figure 1 It can be known that 1511cm -1 and 1581cm -1 The typical band at 1260 cm⁻¹ is due to the C=C vibration in the aromatic ring. -1 and 1076cm -1 The characteristic peak at 1365 cm⁻¹ represents the symmetric and asymmetric COC stretching vibrations in the benzoxazine ring. -1 and 3365cm -1 These are the stretching absorption peaks of -CH2 in the oxazine ring, and the peaks at 1260 cm⁻¹ for the functional groups of PDMS. -1 (Si-CH3) and 1000cm -1 ~1100cm -1 The (Si-O-Si) peak still exists, and it is at 1700 cm⁻¹. -1 ~1750cm -1 With 1600cm -1 ~1680cm -1 The appearance of new peaks indicates the introduction of -COOH and C=C groups from PMDS. As shown above, the characteristic peaks of different functional groups of benzoxazine and PDMS were successfully detected, thus confirming the successful preparation of PDMS-modified benzoxazine resin AD. The samples obtained in Examples 5-10, after infrared spectroscopy testing, also exhibited the same characteristic peaks as the samples obtained in Examples 1-4, further demonstrating the successful preparation of PDMS-modified benzoxazine resin EJ.
[0079] Depend on Figure 3 Thermogravimetric analysis (TGA) revealed that the PDMS-modified benzoxazine phenolic resin coatings A-D all exhibited a new weight loss peak at approximately 275°C on the DTG curves. This peak corresponds to the decomposition characteristics of PDMS segments, indicating the successful introduction of organosilicon. Simultaneously, the maximum thermal decomposition temperature of the coating samples increased to approximately 450°C, a significant improvement compared to unmodified phenolic or ordinary PDMS coatings, indicating a significant enhancement in the thermal stability of the organosilicon-modified phenolic resin. Furthermore, coating EJ obtained in Examples 5-10 also exhibited similar thermogravimetric characteristics, further verifying the successful implementation of organosilicon modification in all samples and its effective improvement in the thermal stability of the coatings under high-temperature conditions. Therefore, it can be inferred that the PDMS-modified benzoxazine phenolic resin coatings prepared in this disclosure can maintain structural integrity even under harsh high-temperature environments.
[0080] Depend on Figure 4It is known that the adhesion of PDMS coatings in existing technologies is generally below 0.4 MPa, and even after modification with silane bonds, it can only reach about 1 MPa. However, the resin modified by combining PDMS with benzoxazine exhibits superior mechanical properties. (See [link to relevant documentation]). Figure 2 The adhesion of the PDMS-modified benzoxazine resin coating AD obtained in Examples 1-4 ranges from 4.68 to 5.95 MPa, which is 4 to 6 times that of the existing PDMS coatings, demonstrating a significant improvement. Furthermore, further testing showed that the adhesion of the resin coating EJ obtained in Examples 5-10 is all above 4.7 MPa. Therefore, it is evident that the organosilicon-modified phenolic resin provided in this disclosure possesses excellent mechanical properties.
[0081] Depend on Figure 5 , Figure 6 Electrochemical test results show that after PDMS-modified benzoxazine phenolic resin is coated onto the substrate surface, its impedance modulus still reaches the order of 10^10 at d63, and its Nyquist plot shows only a single arc, indicating that no corrosion has occurred. In contrast, the impedance modulus of a typical PDMS coating (unmodified PDMS coating) drops to the order of 10^4 to 10^5 at d7, and its Nyquist plot shows multiple arcs, indicating that corrosion has occurred. This comparison demonstrates that the organosilicon-modified phenolic resin disclosed in this invention exhibits excellent corrosion resistance.
[0082] Depend on Figure 7 It can be seen that, compared with the blank substrate, the number of bacteria on PDMS-modified benzoxazine phenolic resin coatings A-D is significantly reduced. Further analysis revealed that coatings A-D exhibit different emphases in their anti-adhesion effects against the two types of bacteria: for antibacterial adhesion, the order of antibacterial effect from greatest to least is coating C, coating B, coating A, and coating D; for antibacterial adhesion against *Pseudomonas*, the order of antibacterial effect from greatest to least is coating D, coating B, coating A, and coating C. Furthermore, further testing showed that coatings E-J also exhibit excellent antibacterial adhesion.
[0083] The above description is merely an example of this disclosure and is not intended to limit this disclosure in any way. Although this disclosure is presented above with preferred embodiments, it is not intended to limit this disclosure. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solutions disclosed herein are equivalent to equivalent implementation cases and are all within the scope of the technical solutions disclosed herein.
Claims
1. An organosilicon-modified phenolic resin, wherein, Its raw materials include curcumin, paraformaldehyde or formaldehyde, and organosilicon compounds; the organosilicon compounds include at least one of polydimethylsiloxane, polymethylhydrosiloxane, polyethylmethylsiloxane, polyphenylmethylsiloxane, and epoxysiloxane.
2. The organosilicon-modified phenolic resin according to claim 1, wherein, The raw materials also include silane coupling agents containing primary amine groups, preferably γ-aminopropyltriethoxysilane.
3. The organosilicon-modified phenolic resin according to claim 2, wherein, The molar ratio of curcumin, paraformaldehyde or formaldehyde, silane coupling agent containing primary amine group, and organosilicon compound is (0.01~20):(0.02~20):(0.01~20):(0.01~20).
4. A method for preparing an organosilicon-modified phenolic resin coating, wherein, Including the following steps: Step S1: The raw material curcumin, paraformaldehyde or formaldehyde, and organosilicon compound are reacted in an organic solvent to obtain a modified benzoxazine monomer, which is then filtered; wherein, the organosilicon compound includes at least one of polydimethylsiloxane, polymethylhydrosiloxane, polyethylmethylsiloxane, polyphenylmethylsiloxane, and epoxysiloxane. Step S2: Remove excess organic solvent from the filtered solution by rotary evaporation, and then dissolve the modified benzoxazine monomer in the organic solvent to obtain the first solution; Step S3: Remove excess organic solvent by rotary evaporation of the first solution and apply it to the substrate surface; Step S4: Heat and cure the substrate surface treated in step S3 to form an organosilicon-modified phenolic resin coating.
5. The method for preparing the organosilicon-modified phenolic resin coating according to claim 4, wherein, The raw materials also include silane coupling agents containing primary amine groups, preferably γ-aminopropyltriethoxysilane.
6. The method for preparing the organosilicon-modified phenolic resin coating according to claim 4, wherein, The substrate includes at least one of a metal substrate, a glass substrate, a ceramic substrate, an enamel substrate, a polymer substrate, and a composite substrate formed from the above substrates.
7. The method for preparing the organosilicon-modified phenolic resin coating according to claim 4, wherein, In step S4, the temperature for heating and curing is 10℃~300℃, and the heating and curing time is 0.1h~120h.
8. The method for preparing the organosilicon-modified phenolic resin coating according to claim 4, wherein, In step S4, the reaction conditions are: heating temperature of 50℃~150℃, and curing reaction time of 4h~24h.
9. The method for preparing the organosilicon-modified phenolic resin coating according to claim 5, wherein, The molar ratio of curcumin, paraformaldehyde, silane coupling agent containing primary amine group, and organosilicon compound is (0.01~20):(0.02~20):(0.01~20):(0.01~20).