Modified antibacterial waterborne alkyd resin and its preparation method

Abstract

The present invention discloses a modified antibacterial water-based alkyd resin and a preparation method thereof, belonging to the technical field of alkyd resin preparation. The modified antibacterial water-based alkyd resin is composed of the following components by weight: 14-30 parts of a polyol, 7-35 parts of a polyacid, 20-50 parts of a fatty acid, 2-5 parts of a water-based monomer, 3-10 parts of a neutralizing agent, 0.5-5 parts of a modified antibacterial agent, 2-6 parts of a compounding agent, and 10-40 parts of deionized water. The water-based alkyd resin prepared by the present invention has excellent antibacterial properties, corrosion resistance, and wear resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of alkyd resin preparation, and particularly relates to a modified antibacterial water-based alkyd resin and a preparation method thereof. Background Art

[0002] Driven by market demand, waterborne alkyd resins, as a green alternative to traditional solvent-based alkyd resins, have developed rapidly in the coatings field in recent years. However, their inherent technical defects have significantly restricted their scope of application: poor water resistance due to the ester bond structure, insufficient weather resistance due to the flexibility of the molecular chain, and the lack of antibacterial properties of unmodified resins have become core bottlenecks restricting their application in high-demand scenarios. Due to the presence of a large number of ester bonds in the molecular chain, traditional waterborne alkyd resins are prone to hydrolysis reactions in weakly alkaline environments, resulting in a decrease in gloss, hardness, and even peeling of the coating in humid environments. At the same time, the flexible structure of the resin main chain makes it prone to chain breakage under ultraviolet radiation, causing the coating to powder and discolor, and unable to meet the long-term protection needs of outdoor facilities. In addition, conventional alkyd resins lack antibacterial properties, and their application in fields with strict requirements for microbial control, such as medical equipment and food packaging, poses a major safety hazard.

[0003] Patent CN110591431A discloses a rare earth modified waterborne alkyd resin antibacterial luminescent coating, which is composed of 35.0-55.0 parts of rare earth modified waterborne alkyd resin, 15.0-25.0 parts of fluorine modified waterborne alkyd resin, 0.0-25.0 parts of filler, 1.2-6.0 parts of additive, 2.5-6.5 parts of solid glass microspheres, 3.5-6.5 parts of film-forming additive, and 10.0-30.0 parts of deionized water; wherein, rare earth modified waterborne alkyd resin is 35.0-55.0 parts of rare earth modified waterborne alkyd resin, 15.0-25.0 parts of fluorine modified waterborne alkyd resin, 0.0-25.0 parts of filler, 1.2-6.0 parts of additive, 2.5-6.5 parts of solid glass microspheres, 3.5-6.5 parts of film-forming additive, and 10.0-30.0 parts of deionized water. The water-based alkyd resin is mainly prepared by reacting vegetable oil, organic acid anhydride, carboxylic acid Schiff base, polyol, benzoic acid, dihydroxymethylpropionic acid, rare earth ethanol solution, sodium ethanol ethanol solution and neutralizer; the rare earth modified water-based alkyd resin antibacterial luminous coating prepared by the invention does not require the addition of luminous powder and antibacterial properties, so that it has good aging resistance and long-lasting antibacterial properties. However, the antibacterial properties, wear resistance and corrosion resistance of the resin material prepared by this method still have room for improvement. Summary of the Invention

[0004] The purpose of the present invention is to provide a modified antibacterial water-based alkyd resin and a preparation method thereof, so as to solve the technical problem that the alkyd resin in the prior art has poor antibacterial performance, wear resistance and corrosion resistance.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The invention provides a modified antibacterial water-based alkyd resin, which is composed of the following components in parts by weight: 14-30 parts of polyol, 7-35 parts of polyacid, 20-50 parts of fatty acid, 2-5 parts of water-based monomer, 3-10 parts of neutralizer, 0.5-5 parts of modified antibacterial agent, 2-6 parts of compounding agent, and 10-40 parts of deionized water.

[0007] Preferably, the preparation method of the modified antibacterial agent comprises the following steps:

[0008] Q1: Hexamethylenetetramine was added to a container containing acetic acid, heated and stirred until dissolved, and then eugenol was added. Stirring was continued, and then hydrochloric acid solution was added. After heating and stirring, the reaction was completed, cooled, washed, extracted, rotary evaporated, and purified to obtain intermediate 1;

[0009] Q2: Add 4-hydrazinopyridine hydrochloride to a pressure-resistant tube, then add sodium bicarbonate and N,N-dimethylformamide, stir to dissolve, add intermediate 1, heat to react, and after the reaction is complete, extract, dry, concentrate, dissolve, add petroleum ether, let stand, and filter to obtain intermediate 2;

[0010] Q3: Triethylamine, intermediate 2, and dichloromethane were added to a container, stirred in an ice bath under nitrogen atmosphere, and then methacryloyl chloride was added dropwise. After stirring in an ice bath, the reaction was continued with stirring at room temperature. After the reaction was completed, the mixture was filtered, precipitated, extracted, dried, rotary evaporated, and distilled under reduced pressure to obtain intermediate 3.

[0011] Q4: Add methacryloxypropyltriethoxysilane, intermediate 3, N-vinylpyrrolidone and azobisisobutyronitrile to a container filled with tetrahydrofuran, heat and stir to react under a nitrogen environment, and after the reaction is completed, rotary evaporation, precipitation, dissolution, purification, and vacuum drying are performed to obtain a modified antibacterial agent.

[0012] In the above process, the synthetic reaction formula of the modified antibacterial agent is as follows:

[0013]

[0014] The results of mass spectrometry analysis of intermediate 1 were: m / z: 192.08 (100.0%), 193.08 (12.1%); the results of mass spectrometry analysis of intermediate 2 were: m / z: 283.13 (100.0%), 284.14 (17.6%), 285.14 (1.9%), 284.13(1.1%); the results of mass spectrometry analysis of intermediate 3 were: m / z: 351.16 (100.0%), 352.16 (23.1%), 353.17(2.3%).

[0015] Preferably, in Q1, the dosage ratio of hexamethylenetetramine, acetic acid, eugenol and hydrochloric acid solution is (20-24.82) g: (80-100) mL: (5.12-5.32) g: (10-15) mL, the temperature for heating and stirring until dissolution is 120-130°C, the stirring time is 30-45 minutes, and the stirring time is continued for 5-8 hours. The concentration of the hydrochloric acid solution is 2 mol / L, the heating and stirring reaction temperature is 120-130°C, and the reaction time is 30-45 minutes.

[0016] Preferably, in Q2, the amount ratio of 4-hydrazinopyridine hydrochloride, sodium bicarbonate, N,N-dimethylformamide and intermediate 1 is (0.26-0.32) g: (0.15-0.19) g: (10-20) mL: (0.38-0.42) g, the heating reaction temperature is 80-90°C, and the reaction time is 2-4 h; in Q3, the amount ratio of triethylamine, intermediate 2, dichloromethane and methacryloyl chloride is (6.8-9.2) mL: (20.01-23.33) g: (50-75) mL: (10-12) mL, the reaction time is 30-45 min with stirring in an ice bath, the addition rate is 1 mL / 5 min, the stirring time in an ice bath is 30-45 min, and the stirring reaction time at room temperature is continued for 48-52 h.

[0017] Preferably, in Q4, the amount ratio of methacryloxypropyltriethoxysilane, intermediate 3, N-vinyl pyrrolidone, azobisisobutyronitrile and tetrahydrofuran is (9.2-10.7) g: (20.3-44.5) g: (20.2-44.8) g: (0.2-0.8) g: (200-250) mL, the heating and stirring reaction temperature is 70-75°C, and the reaction time is 10-12 h.

[0018] Preferably, the preparation method of the composite agent comprises the following steps:

[0019] S1: Add silica to an ethanol solution, heat and stir to mix, then add a silane coupling agent KH-550 solution, continue stirring to react, filter after completion of the reaction, and dry to obtain modified silica; under a nitrogen atmosphere, add the modified silica to a container, then dropwise add hexafluorobutyl methacrylate, raise the temperature to react after completion of the reaction, and reduce the pressure and filter to obtain product A;

[0020] S2: preheating the product A and the meta-xylylenediisocyanate prepolymer respectively, then mixing and aging them to obtain a composite agent.

[0021] In the above process, the synthetic reaction formula of the composite agent is as follows:

[0022]

[0023] Preferably, in S1, the amount ratio of silica, ethanol solution and silane coupling agent KH-550 is (10-20) g: (10-14) mL: (1-2) g, the volume fraction of the ethanol solution is 90vt%, the heating and stirring temperature is 45-65°C, the stirring time is 4-6h, and the weight fraction of the silane coupling agent KH-550 solution is 6wt%; the amount ratio of modified silica and hexafluorobutyl methacrylate is (2.7-3.6) g: (5.3-6.8) g, the heating reaction temperature is 40-45°C, and the reaction time is 10-20h.

[0024] Preferably, in S2, the preheating temperature is 60-90°C, the usage ratio of product A to meta-xylylenediisocyanate prepolymer is (3.4-5.6) g: (4.2-6.8) g, the mixing speed is 3000-3500 rpm, the aging temperature is 90-110°C, and the time is 20-24 h.

[0025] Preferably, the preparation method of the modified antibacterial waterborne alkyd resin comprises the following steps:

[0026] Step 1: Add polyol, polyacid and fatty acid into a reactor, heat and react under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix;

[0027] Step 2: Cool the alkyd resin matrix, then add the water-based monomer and continue the reaction. After cooling, add the neutralizer and continue stirring. Then add the modified antibacterial agent and the composite agent, stir and mix, add deionized water, and filter to obtain the modified antibacterial water-based alkyd resin.

[0028] Preferably, in the step 1, the heating reaction temperature is 180-230°C; in the step 2, the mixture is cooled to 60-80°C, the reaction time is continued for 30-60 minutes, the mixture is cooled to 30-40°C, the stirring time is continued for 20-30 minutes, the stirring mixing rate is 500-800 rpm, and the mixing time is 15-30 minutes.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] 1. The present invention adds the prepared modified antibacterial agent and composite agent to the resin, which can effectively improve the antibacterial property, corrosion resistance and wear resistance of the resin.

[0031] 2. The modified antibacterial agent prepared in the present invention is added to the water-based alkyd resin, which can effectively improve the antibacterial properties of the resin. The pyridine ring and hydrazone bond contained in the modified antibacterial agent can adsorb bacteria through electrostatic action and destroy the membrane integrity. The pyrrolidine structure contained in the agent can also inhibit bacterial adhesion and reduce the formation of biofilm, thereby achieving an antibacterial effect.

[0032] 3. The present invention adds the prepared composite agent to a water-based alkyd resin, which can effectively improve the corrosion resistance and wear resistance of the resin. The fluorine-containing segments contained in the composite agent can form a hydrophobic layer to reduce the penetration of water molecules. The modified silica forms a chemical bond with the resin matrix, reducing interface defects and blocking the invasion of moisture and corrosion-resistant ions, thereby improving the corrosion resistance of the resin. The modified silica contained in the composite agent can be used as an inorganic nanoparticle as a reinforcing filler, which can reduce stress concentration and improve the wear resistance of the resin. DETAILED DESCRIPTION

[0033] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] Example 1: This example discloses a method for preparing a modified antibacterial agent, comprising the following steps:

[0035] Q1: Add 22.41 g of hexamethylenetetramine to a container containing 90 mL of acetic acid, heat and stir at 125°C for 30 min until dissolved, then add 5.22 g of eugenol, continue stirring for 6 h, then add 12.5 mL of 2 mol / L hydrochloric acid solution, heat and stir at 120°C for 45 min. After the reaction, cool, wash, extract, rotary evaporate, and purify to obtain intermediate 1;

[0036] Q2: Add 0.29 g of 4-hydrazinopyridine hydrochloride to a pressure tube, then add 0.17 g of sodium bicarbonate and 15 mL of N,N-dimethylformamide. After stirring to dissolve, add 0.4 g of intermediate 1 and heat to 80°C for 4 h. After the reaction, extract, dry, concentrate, dissolve, add petroleum ether, let stand, and filter to obtain intermediate 2.

[0037] Q3: 8 mL of triethylamine, 21.67 g of intermediate 2, and 62.5 mL of dichloromethane were added to a container. Under nitrogen atmosphere, the mixture was stirred in an ice bath for 45 min. Then, 11 mL of methacryloyl chloride was added dropwise at a rate of 1 mL / 5 min. After stirring in an ice bath for 30 min, the mixture was stirred at room temperature for 48 h. After the reaction was completed, the mixture was filtered, precipitated, extracted, dried, rotary evaporated, and distilled under reduced pressure to obtain intermediate 3.

[0038] Q4: 9.8 g of methacryloxypropyltriethoxysilane, 32.4 g of intermediate 3, 32.5 g of N-vinylpyrrolidone and 0.5 g of azobisisobutyronitrile were added to a container containing 225 mL of tetrahydrofuran. The mixture was heated and stirred at 75 ° C under a nitrogen environment for 12 hours. After the reaction was completed, the mixture was rotary evaporated, precipitated, dissolved, purified and vacuum dried to obtain a modified antibacterial agent.

[0039] This embodiment discloses a method for preparing a composite agent, comprising the following steps:

[0040] S1: 15 g of silica was added to 12 mL of a 90 wt% ethanol solution, heated and stirred at 60°C for 4 h, and then 1.5 g of a 6 wt% silane coupling agent KH-550 solution was added. The mixture was stirred and reacted. After the reaction was completed, the mixture was filtered and dried to obtain modified silica. Under a nitrogen atmosphere, 3.05 g of the modified silica was added to a container, and then 6.05 g of hexafluorobutyl methacrylate was added dropwise. After the addition was complete, the mixture was heated at 45°C for 12 h. After the reaction was completed, the mixture was filtered and dried under reduced pressure to obtain product A.

[0041] S2: 4.5 g of product A and 5.5 g of m-xylylenediisocyanate prepolymer were preheated to 70° C., mixed at 3500 rpm, and aged at 100° C. for 24 h to obtain a composite agent.

[0042] This embodiment discloses a modified antibacterial water-based alkyd resin, which is composed of the following components by weight: 22 parts of trimethylolpropane, 21 parts of phthalic anhydride, 35 parts of linoleic acid, 3.5 parts of sodium 5-sulfonate isophthalate, 6.5 parts of triethylamine, 2.7 parts of a modified antibacterial agent, 4 parts of a compounding agent, and 25 parts of deionized water.

[0043] This embodiment discloses a method for preparing a modified antibacterial waterborne alkyd resin, comprising the following steps:

[0044] Step 1: Add trimethylolpropane, phthalic anhydride and linoleic acid into a reactor, heat at 190°C under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix;

[0045] Step 2: Cool the alkyd resin matrix to 60°C, then add sodium 5-sulfoisophthalate, continue the reaction for 30 minutes, cool to 30°C, add triethylamine, continue stirring for 30 minutes, then add the modified antibacterial agent and the composite agent, stir and mix at 800 rpm for 30 minutes, add deionized water, filter, and obtain a modified antibacterial water-based alkyd resin.

[0046] Example 2: This example discloses a method for preparing a modified antibacterial agent, comprising the following steps:

[0047] Q1: Add 20 g of hexamethylenetetramine to a container containing 100 mL of acetic acid, heat and stir at 125°C for 30 min until dissolved, then add 5.12 g of eugenol, continue stirring for 6 h, then add 15 mL of 2 mol / L hydrochloric acid solution, heat and stir at 120°C for 45 min. After the reaction, cool, wash, extract, rotary evaporate, and purify to obtain intermediate 1;

[0048] Q2: Add 0.26 g of 4-hydrazinopyridine hydrochloride to a pressure tube, then add 0.15 g of sodium bicarbonate and 20 mL of N,N-dimethylformamide. After stirring to dissolve, add 0.42 g of intermediate 1 and heat to 80°C for 4 h. After the reaction, extract, dry, concentrate, dissolve, add petroleum ether, let stand, and filter to obtain intermediate 2.

[0049] Q3: 6.8 mL of triethylamine, 20.01 g of intermediate 2, and 50 mL of dichloromethane were added to a container. Under nitrogen atmosphere, the mixture was stirred in an ice bath for 45 min. Then, 10 mL of methacryloyl chloride was added dropwise at a rate of 1 mL / 5 min. After stirring in an ice bath for 30 min, the mixture was stirred at room temperature for 48 h. After the reaction, the mixture was filtered, precipitated, extracted, dried, rotary evaporated, and distilled under reduced pressure to obtain intermediate 3.

[0050] Q4: 9.2 g of methacryloxypropyltriethoxysilane, 20.3 g of intermediate 3, 20.2 g of N-vinylpyrrolidone and 0.2 g of azobisisobutyronitrile were added to a container containing 200 mL of tetrahydrofuran. The mixture was heated and stirred at 75 ° C for 12 h under a nitrogen environment. After the reaction was completed, the mixture was rotary evaporated, precipitated, dissolved, purified and vacuum dried to obtain a modified antibacterial agent.

[0051] This embodiment discloses a method for preparing a composite agent, comprising the following steps:

[0052] S1: 10 g of silica was added to 14 mL of a 90 wt% ethanol solution, heated and stirred at 60°C for 4 h, and then 1 g of a 6 wt% silane coupling agent KH-550 solution was added. The mixture was stirred and reacted. After the reaction was completed, the mixture was filtered and dried to obtain modified silica. Under a nitrogen atmosphere, 2.7 g of modified silica was added to a container, and then 5.3 g of hexafluorobutyl methacrylate was added dropwise. After the addition was complete, the mixture was heated at 45°C for 12 h. After the reaction was completed, the mixture was filtered and dried under reduced pressure to obtain product A.

[0053] S2: 3.4 g of product A and 4.2 g of m-xylylenediisocyanate prepolymer were preheated to 70° C., mixed at 3500 rpm, and aged at 100° C. for 24 h to obtain a composite agent.

[0054] This embodiment discloses a modified antibacterial water-based alkyd resin, which is composed of the following components by weight: 14 parts of trimethylolpropane, 35 parts of phthalic anhydride, 50 parts of linoleic acid, 2 parts of sodium 5-sulfonate isophthalate, 10 parts of triethylamine, 0.5 parts of a modified antibacterial agent, 2 parts of a compounding agent, and 10 parts of deionized water.

[0055] This embodiment discloses a method for preparing a modified antibacterial waterborne alkyd resin, comprising the following steps:

[0056] Step 1: Add trimethylolpropane, phthalic anhydride and linoleic acid into a reactor, heat at 190°C under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix;

[0057] Step 2: Cool the alkyd resin matrix to 60°C, then add sodium 5-sulfoisophthalate, continue the reaction for 30 minutes, cool to 30°C, add triethylamine, continue stirring for 30 minutes, then add the modified antibacterial agent and the composite agent, stir and mix at 800 rpm for 30 minutes, add deionized water, filter, and obtain a modified antibacterial water-based alkyd resin.

[0058] Example 3: This example discloses a method for preparing a modified antibacterial agent, comprising the following steps:

[0059] Q1: Add 24.82 g of hexamethylenetetramine to a container containing 80 mL of acetic acid, heat and stir at 125°C for 30 min until dissolved, then add 5.32 g of eugenol, continue stirring for 6 h, then add 10 mL of 2 mol / L hydrochloric acid solution, heat and stir at 120°C for 45 min. After the reaction, cool, wash, extract, rotary evaporate, and purify to obtain intermediate 1;

[0060] Q2: Add 0.32 g of 4-hydrazinopyridine hydrochloride to a pressure tube, then add 0.19 g of sodium bicarbonate and 10 mL of N,N-dimethylformamide. After stirring to dissolve, add 0.38 g of intermediate 1 and heat at 80°C for 4 h. After the reaction, extract, dry, concentrate, dissolve, add petroleum ether, let stand, and filter to obtain intermediate 2.

[0061] Q3: 9.2 mL of triethylamine, 23.33 g of intermediate 2, and 75 mL of dichloromethane were added to a container. Under nitrogen atmosphere, the mixture was stirred in an ice bath for 45 min. Then, 12 mL of methacryloyl chloride was added dropwise at a rate of 1 mL / 5 min. After stirring in an ice bath for 30 min, the mixture was stirred at room temperature for 48 h. After the reaction, the mixture was filtered, precipitated, extracted, dried, rotary evaporated, and distilled under reduced pressure to obtain intermediate 3.

[0062] Q4: 10.7 g of methacryloxypropyltriethoxysilane, 44.5 g of intermediate 3, 44.8 g of N-vinylpyrrolidone and 0.8 g of azobisisobutyronitrile were added to a container containing 250 mL of tetrahydrofuran. The mixture was heated and stirred at 75 ° C under a nitrogen environment for 12 hours. After the reaction was completed, the mixture was rotary evaporated, precipitated, dissolved, purified and vacuum dried to obtain a modified antibacterial agent.

[0063] This embodiment discloses a method for preparing a composite agent, comprising the following steps:

[0064] S1: Add 20 g of silica to 10 mL of 90 wt% ethanol solution, heat and stir at 60°C for 4 h, then add 2 g of 6 wt% silane coupling agent KH-550 solution, continue stirring and react, filter and dry after the reaction to obtain modified silica; under nitrogen environment, add 3.6 g of modified silica to a container, then add 6.8 g of hexafluorobutyl methacrylate dropwise, after the addition is complete, heat at 45°C for 12 h, and after the reaction is complete, filter and dry under reduced pressure to obtain product A;

[0065] S2: 5.6 g of product A and 6.8 g of m-xylylenediisocyanate prepolymer were preheated to 70° C., mixed at 3500 rpm, and aged at 100° C. for 24 h to obtain a composite agent.

[0066] This embodiment discloses a modified antibacterial water-based alkyd resin, which is composed of the following components by weight: 30 parts of trimethylolpropane, 7 parts of phthalic anhydride, 20 parts of linoleic acid, 5 parts of sodium 5-sulfonate isophthalate, 3 parts of triethylamine, 5 parts of a modified antibacterial agent, 6 parts of a compounding agent, and 40 parts of deionized water.

[0067] This embodiment discloses a method for preparing a modified antibacterial waterborne alkyd resin, comprising the following steps:

[0068] Step 1: Add trimethylolpropane, phthalic anhydride and linoleic acid into a reactor, heat at 190°C under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix;

[0069] Step 2: Cool the alkyd resin matrix to 60°C, then add sodium 5-sulfoisophthalate, continue the reaction for 30 minutes, cool to 30°C, add triethylamine, continue stirring for 30 minutes, then add the modified antibacterial agent and the composite agent, stir and mix at 800 rpm for 30 minutes, add deionized water, filter, and obtain a modified antibacterial water-based alkyd resin.

[0070] Example 4: This example discloses a method for preparing a modified antibacterial agent, comprising the following steps:

[0071] Q1: Add 21.13 g of hexamethylenetetramine to a container containing 85 mL of acetic acid, heat and stir at 125°C for 30 min until dissolved, then add 5.17 g of eugenol, continue stirring for 6 h, then add 11 mL of 2 mol / L hydrochloric acid solution, heat and stir at 120°C for 45 min. After the reaction, cool, wash, extract, rotary evaporate, and purify to obtain intermediate 1;

[0072] Q2: Add 0.27 g of 4-hydrazinopyridine hydrochloride to a pressure tube, then add 0.16 g of sodium bicarbonate and 12 mL of N,N-dimethylformamide. After stirring to dissolve, add 0.39 g of intermediate 1 and heat to 80°C for 4 h. After the reaction, extract, dry, concentrate, dissolve, add petroleum ether, let stand, and filter to obtain intermediate 2.

[0073] Q3: 7.4 mL of triethylamine, 20.58 g of intermediate 2, and 55 mL of dichloromethane were added to a container. Under nitrogen atmosphere, the mixture was stirred in an ice bath for 45 min. Then, 10.5 mL of methacryloyl chloride was added dropwise at a rate of 1 mL / 5 min. After stirring in an ice bath for 30 min, the mixture was stirred at room temperature for 48 h. After the reaction, the mixture was filtered, precipitated, extracted, dried, rotary evaporated, and distilled under reduced pressure to obtain intermediate 3.

[0074] Q4: 9.5 g of methacryloxypropyltriethoxysilane, 25.1 g of intermediate 3, 25.1 g of N-vinylpyrrolidone and 0.7 g of azobisisobutyronitrile were added to a container containing 210 mL of tetrahydrofuran. The mixture was heated and stirred at 75 ° C under a nitrogen environment for 12 hours. After the reaction was completed, the mixture was rotary evaporated, precipitated, dissolved, purified and vacuum dried to obtain a modified antibacterial agent.

[0075] This embodiment discloses a method for preparing a composite agent, comprising the following steps:

[0076] S1: 18 g of silica was added to 11 mL of a 90 wt% ethanol solution, heated and stirred at 60°C for 4 h, and then 1.2 g of a 6 wt% silane coupling agent KH-550 solution was added. The mixture was stirred and reacted. After the reaction was completed, the mixture was filtered and dried to obtain modified silica. Under a nitrogen atmosphere, 2.9 g of the modified silica was added to a container, and then 5.5 g of hexafluorobutyl methacrylate was added dropwise. After the addition was complete, the mixture was heated at 45°C for 12 h. After the reaction was completed, the mixture was filtered and dried under reduced pressure to obtain product A.

[0077] S2: 3.8 g of product A and 4.8 g of m-xylylenediisocyanate prepolymer were preheated to 70° C., mixed at 3500 rpm, and aged at 100° C. for 24 h to obtain a composite agent.

[0078] This embodiment discloses a modified antibacterial water-based alkyd resin, which is composed of the following components by weight: 18 parts of trimethylolpropane, 14 parts of phthalic anhydride, 25 parts of linoleic acid, 3 parts of sodium 5-sulfonate isophthalate, 4 parts of triethylamine, 1.2 parts of a modified antibacterial agent, 3 parts of a compounding agent, and 20 parts of deionized water.

[0079] This embodiment discloses a method for preparing a modified antibacterial waterborne alkyd resin, comprising the following steps:

[0080] Step 1: Add trimethylolpropane, phthalic anhydride and linoleic acid into a reactor, heat at 190°C under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix;

[0081] Step 2: Cool the alkyd resin matrix to 60°C, then add sodium 5-sulfoisophthalate, continue the reaction for 30 minutes, cool to 30°C, add triethylamine, continue stirring for 30 minutes, then add the modified antibacterial agent and the composite agent, stir and mix at 800 rpm for 30 minutes, add deionized water, filter, and obtain a modified antibacterial water-based alkyd resin.

[0082] Comparative Example 5: This embodiment discloses a method for preparing a modified antibacterial agent, comprising the following steps:

[0083] Q1: Add 23.19 g of hexamethylenetetramine to a container containing 95 mL of acetic acid, heat and stir at 125°C for 30 min until dissolved, then add 5.27 g of eugenol, continue stirring for 6 h, then add 14 mL of 2 mol / L hydrochloric acid solution, heat and stir at 120°C for 45 min. After the reaction, cool, wash, extract, rotary evaporate, and purify to obtain intermediate 1;

[0084] Q2: Add 0.31 g of 4-hydrazinopyridine hydrochloride to a pressure tube, then add 0.18 g of sodium bicarbonate and 18 mL of N,N-dimethylformamide. After stirring to dissolve, add 0.41 g of intermediate 1 and heat to 80°C for 4 h. After the reaction, extract, dry, concentrate, dissolve, add petroleum ether, let stand, and filter to obtain intermediate 2.

[0085] Q3: 8.8 mL of triethylamine, 22.51 g of intermediate 2, and 70 mL of dichloromethane were added to a container. Under nitrogen atmosphere, the mixture was stirred in an ice bath for 45 min. Then, 11.5 mL of methacryloyl chloride was added dropwise at a rate of 1 mL / 5 min. After stirring in an ice bath for 30 min, the mixture was stirred at room temperature for 48 h. After the reaction, the mixture was filtered, precipitated, extracted, dried, rotary evaporated, and distilled under reduced pressure to obtain intermediate 3.

[0086] Q4: 10.2 g of methacryloxypropyltriethoxysilane, 38.2 g of intermediate 3, 39.9 g of N-vinylpyrrolidone and 0.3 g of azobisisobutyronitrile were added to a container containing 240 mL of tetrahydrofuran. The mixture was heated and stirred at 75 ° C under a nitrogen environment for 12 hours. After the reaction was completed, the mixture was rotary evaporated, precipitated, dissolved, purified and vacuum dried to obtain a modified antibacterial agent.

[0087] This embodiment discloses a method for preparing a composite agent, comprising the following steps:

[0088] S1: 12 g of silica was added to 13 mL of a 90 wt% ethanol solution, heated and stirred at 60°C for 4 h, and then 1.7 g of a 6 wt% silane coupling agent KH-550 solution was added. The mixture was stirred and reacted. After the reaction was completed, the mixture was filtered and dried to obtain modified silica. Under a nitrogen atmosphere, 3.3 g of the modified silica was added to a container, and then 6.6 g of hexafluorobutyl methacrylate was added dropwise. After the addition was complete, the mixture was heated at 45°C for 12 h. After the reaction was completed, the mixture was filtered and dried under reduced pressure to obtain product A.

[0089] S2: 5.2 g of product A and 6.1 g of m-xylylenediisocyanate prepolymer were preheated to 70° C., mixed at 3500 rpm, and aged at 100° C. for 24 h to obtain a composite agent.

[0090] This embodiment discloses a modified antibacterial water-based alkyd resin, which is composed of the following components by weight: 26 parts of trimethylolpropane, 28 parts of phthalic anhydride, 40 parts of linoleic acid, 4 parts of sodium 5-sulfonate isophthalate, 7 parts of triethylamine, 4.5 parts of a modified antibacterial agent, 5 parts of a compounding agent, and 30 parts of deionized water.

[0091] This embodiment discloses a method for preparing a modified antibacterial waterborne alkyd resin, comprising the following steps:

[0092] Step 1: Add trimethylolpropane, phthalic anhydride and linoleic acid into a reactor, heat at 190°C under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix;

[0093] Step 2: Cool the alkyd resin matrix to 60°C, then add sodium 5-sulfoisophthalate, continue the reaction for 30 minutes, cool to 30°C, add triethylamine, continue stirring for 30 minutes, then add the modified antibacterial agent and the composite agent, stir and mix at 800 rpm for 30 minutes, add deionized water, filter, and obtain a modified antibacterial water-based alkyd resin.

[0094] Comparative Example 1: Compared with Example 1, in Comparative Example 1, during the preparation of the modified antibacterial waterborne alkyd resin, no modified antibacterial agent was added, and other conditions remained unchanged.

[0095] Comparative Example 2: Compared with Example 1, in Comparative Example 2, during the preparation of the modified antibacterial waterborne alkyd resin, no complexing agent was added, and other conditions remained unchanged.

[0096] The modified antibacterial waterborne alkyd resins prepared in Examples 1-5 and Comparative Examples 1-2 were subjected to performance tests. The samples were evenly coated on the surface of the substrate to ensure that the paint film was flat, free of bubbles and sagging, and then cured. The cured paint films were tested for antibacterial performance according to GB / T 21866-2008, for abrasion resistance according to GB / T 1768-2006, and for salt water resistance according to HG / T4847-2015. The test results are shown in Table 1.

[0097] Table 1:

[0098]

[0099] The test results in Table 1 show that by using the methods of Examples 1-5, waterborne alkyd resins with excellent antibacterial, corrosion, and wear resistance can be obtained. Comparison of Comparative Example 1 with Examples 1-5 shows that the addition of a modified antibacterial agent can effectively improve the antibacterial properties of the waterborne alkyd resin; and comparison of Comparative Example 2 with Examples 1-5 shows that the addition of a composite agent can effectively improve the corrosion and wear resistance of the waterborne alkyd resin.

[0100] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

[0101] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to specific embodiments. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A modified antibacterial waterborne alkyd resin, characterized in that: The invention comprises the following components in parts by weight: 14-30 parts of polyol, 7-35 parts of polyacid, 20-50 parts of fatty acid, 2-5 parts of water-based monomer, 3-10 parts of neutralizing agent, 0.5-5 parts of modified antibacterial agent, 2-6 parts of compounding agent and 10-40 parts of deionized water, wherein the modified antibacterial agent is obtained by reacting eugenol with formaldehyde obtained by decomposition of hexamethylenetetramine, then undergoing a condensation reaction with 4-hydrazinopyridine hydrochloride, then undergoing an esterification reaction with methacryloyl chloride, and finally undergoing free radical copolymerization under the initiation of azobisisobutyronitrile; the compounding agent is obtained by modifying silicon dioxide with a silane coupling agent KH-550, then undergoing an addition reaction with hexafluorobutyl methacrylate, and finally undergoing a cross-linking reaction with a meta-xylylenediisocyanate prepolymer. The preparation method of the modified antibacterial agent comprises the following steps: Q1: Hexamethylenetetramine was added to a container containing acetic acid, heated and stirred until dissolved, and then eugenol was added. Stirring was continued, and then hydrochloric acid solution was added. After heating and stirring, the reaction was completed, cooled, washed, extracted, rotary evaporated, and purified to obtain intermediate 1; Q2: Add 4-hydrazinopyridine hydrochloride to a pressure-resistant tube, then add sodium bicarbonate and N,N-dimethylformamide, stir to dissolve, add intermediate 1, heat to react, and after the reaction is complete, extract, dry, concentrate, dissolve, add petroleum ether, let stand, and filter to obtain intermediate 2; Q3: Triethylamine, intermediate 2, and dichloromethane were added to a container, stirred in an ice bath under nitrogen atmosphere, and then methacryloyl chloride was added dropwise. After stirring in an ice bath, the reaction was continued with stirring at room temperature. After the reaction was completed, the mixture was filtered, precipitated, extracted, dried, rotary evaporated, and distilled under reduced pressure to obtain intermediate 3. Q4: Methacryloxypropyltriethoxysilane, intermediate 3, N-vinylpyrrolidone and azobisisobutyronitrile were added to a container containing tetrahydrofuran, and heated and stirred under a nitrogen environment to react. After the reaction was completed, rotary evaporation, precipitation, dissolution, purification, and vacuum drying were performed to obtain a modified antibacterial agent; The preparation method of the modified antibacterial water-based alkyd resin comprises the following steps: Step 1: Add polyol, polyacid and fatty acid into a reactor, heat and react under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix; Step 2: Cool the alkyd resin matrix, then add the water-based monomer and continue the reaction. After cooling, add the neutralizer and continue stirring. Then add the modified antibacterial agent and the composite agent, stir and mix, add deionized water, and filter to obtain the modified antibacterial water-based alkyd resin.

2. The modified antibacterial waterborne alkyd resin according to claim 1, wherein In the Q1, the usage ratio of hexamethylenetetramine, acetic acid, eugenol and hydrochloric acid solution is (20-24.82) g: (80-100) mL: (5.12-5.32) g: (10-15) mL.

3. The modified antibacterial waterborne alkyd resin according to claim 1, wherein In Q2, the usage ratio of 4-hydrazinopyridine hydrochloride, sodium bicarbonate, N,N-dimethylformamide and intermediate 1 is (0.26-0.32) g: (0.15-0.19) g: (10-20) mL: (0.38-0.42) g; in Q3, the usage ratio of triethylamine, intermediate 2, dichloromethane and methacryloyl chloride is (6.8-9.2) mL: (20.01-23.33) g: (50-75) mL: (10-12) mL.

4. The modified antibacterial waterborne alkyd resin according to claim 1, wherein In Q4, the usage ratio of methacryloxypropyltriethoxysilane, intermediate 3, N-vinylpyrrolidone, azobisisobutyronitrile and tetrahydrofuran is (9.2-10.7) g: (20.3-44.5) g: (20.2-44.8) g: (0.2-0.8) g: (200-250) mL.

5. The modified antibacterial waterborne alkyd resin according to claim 1, wherein The preparation method of the composite agent comprises the following steps: S1: Add silica to an ethanol solution, heat and stir to mix, then add a silane coupling agent KH-550 solution, continue stirring to react, filter after completion of the reaction, and dry to obtain modified silica; under a nitrogen atmosphere, add the modified silica to a container, then dropwise add hexafluorobutyl methacrylate, raise the temperature to react after completion of the reaction, and reduce the pressure and filter to obtain product A; S2: preheating the product A and the meta-xylylenediisocyanate prepolymer respectively, then mixing and aging them to obtain a composite agent.

6. The modified antibacterial waterborne alkyd resin according to claim 5, characterized in that: In the S1, the usage ratio of silica, ethanol solution and silane coupling agent KH-550 is (10-20) g: (10-14) mL: (1-2) g; the usage ratio of modified silica and hexafluorobutyl methacrylate is (2.7-3.6) g: (5.3-6.8) g.

7. The modified antibacterial waterborne alkyd resin according to claim 5, characterized in that: In the above-mentioned S2, the usage ratio of the product A to the meta-xylylenediisocyanate prepolymer is (3.4-5.6) g: (4.2-6.8) g.

8. The method for preparing the modified antibacterial waterborne alkyd resin according to any one of claims 1 to 7, wherein: The following steps are involved: Step 1: Add polyol, polyacid and fatty acid into a reactor, heat and react under nitrogen protection, and dehydrate after the reaction to obtain an alkyd resin matrix; Step 2: Cool the alkyd resin matrix, then add the water-based monomer and continue the reaction. After cooling, add the neutralizer and continue stirring. Then add the modified antibacterial agent and the composite agent, stir and mix, add deionized water, and filter to obtain the modified antibacterial water-based alkyd resin.

9. The method for preparing the modified antibacterial water-based alkyd resin according to claim 8, wherein: In the step 1, the heating reaction temperature is 180-230°C; in the step 2, the mixture is cooled to 60-80°C, the reaction time is continued for 30-60 minutes, the mixture is cooled to 30-40°C, the stirring time is continued for 20-30 minutes, the stirring mixing rate is 500-800 rpm, and the mixing time is 15-30 minutes.

Images