Thermostatic fluorinated modified basalt epoxy ceramic inner wall paint and preparation method thereof

Abstract

The application discloses a constant-temperature fluorinated modified basalt epoxy ceramic inner wall paint and a preparation method, which is an A / B two-component non-toxic and environment-friendly matching system; the A component comprises food-grade non-toxic epoxy resin, constant-temperature fluorinated modified basalt flake, high-aluminum ceramic powder, inorganic silver-zinc composite antibacterial agent, environment-friendly auxiliary agent, environment-friendly solvent and the like; the B component is a food-grade non-toxic epoxy curing agent; and the construction quality ratio is 3.5:1 to 4:1.The paint is free of heavy metals and harmful precipitation, completely meets the GB / T17219 drinking water safety standard, can resist 180-day long-term water immersion, and has no peeling, cracking and falling-off phenomenon, solves the technical problems of poor water resistance, weak antibacterial property, easy precipitation and short protection life of traditional drinking water surface paint, and is suitable for long-acting corrosion-resistant and antibacterial protection of the inner walls of various municipal drinking water pipelines, water storage equipment and water purification tanks.

Description

Technical Field

[0001] This invention belongs to the technical field of anti-corrosion and antibacterial coatings for drinking water pipelines, and particularly relates to a constant-temperature fluorinated modified basalt epoxy ceramic (BEC) inner wall coating and its preparation method. Background Technology

[0002] Existing antibacterial coatings for drinking water pipelines have significant drawbacks: heavy metal-based antibacterial coatings are prone to leaching harmful substances, failing to meet the GB 5749 drinking water standard and posing a risk of secondary water pollution; ordinary non-toxic antibacterial coatings have low antibacterial activity, short duration of action, and are easily deactivated, failing to provide long-term antibacterial protection. Conventional epoxy topcoats have poor hydrolysis and erosion resistance, and are prone to aging, peeling, and leakage under long-term water flow and alternating wet and dry conditions. The humid environment inside the pipeline easily breeds bacteria and algae, forming biofilms and deteriorating water quality.

[0003] Existing basalt flakes are only modified with a single silane or without modification, resulting in weak interfacial bonding with food-grade resin, insufficient coating density, and poor resistance to water erosion and hydrolysis. They cannot simultaneously meet the multiple requirements of drinking water safety, long-lasting antibacterial effect, and water resistance and corrosion prevention. Summary of the Invention

[0004] To address the shortcomings of existing drinking water pipe coatings, such as heavy metal leaching, short antibacterial duration, poor water erosion resistance, insufficient powder compatibility, and easy deactivation of antibacterial components, this invention provides a constant-temperature fluorinated modified basalt epoxy ceramic inner wall coating and its preparation method. Utilizing a dual-modification process of silane activation and constant-temperature fluorination, a food-grade non-toxic formula, and a low-temperature antibacterial post-treatment activation locking process, this invention achieves a breakthrough in comprehensive performance, including non-toxic safety, long-lasting antibacterial effect, and high water erosion resistance.

[0005] The present invention provides a constant-temperature fluorinated modified basalt epoxy ceramic inner wall coating, which is a two-component, non-toxic and environmentally friendly system consisting of components A and B.

[0006] Component A is prepared from the following raw materials by mass percentage: 50%–60% food-grade non-toxic epoxy resin, 12%–30% constant-temperature fluorinated modified basalt flakes, 10%–15% high-alumina ceramic powder, 2%–4% inorganic silver-zinc composite antibacterial agent, 3%–6% environmentally friendly additives, and the balance of environmentally friendly solvent.

[0007] Component B is a food-grade, non-toxic epoxy curing agent, and the mixing ratio of components A and B during construction is 3.5:1 to 4:1.

[0008] Furthermore, the isothermal fluorinated modified basalt flakes are 1000-mesh iron-free basalt flakes with a particle size of 8–15 μm, a flake thickness-to-diameter ratio ≥12:1, and an iron impurity content ≤50 ppm.

[0009] The isothermal fluorinated modified basalt flakes are first activated and modified by KH-560 silane wet process, and then subjected to isothermal fluorination surface modification treatment.

[0010] The KH-560 silane wet activation modification is specifically performed as follows: 1000-mesh iron-free basalt flakes are screened, washed with water to remove impurities, and dried at 110℃; KH-560 silane coupling agent is added at a dosage of 1.2% of the powder mass; the reaction is carried out at a constant temperature of 65℃ in a 4wt% sodium hydroxide aqueous solution with stirring for 2 hours; then, the mixture is washed with deionized water until neutral, and vacuum dried at 110℃ for 2 hours.

[0011] The isothermal fluorination surface modification is specifically performed as follows: ethanol is diluted to 1 wt%, and perfluorodecyltriethoxysilane (PFTS) is added; the reaction is carried out at a constant temperature of 70°C for 12 hours under a closed nitrogen inert environment; then the mixture is washed three times with anhydrous ethanol and dried at a low temperature of 80°C.

[0012] Furthermore, the food-grade non-toxic epoxy resin uses drinking water-specific bisphenol A type E55 epoxy resin.

[0013] Furthermore, the environmentally friendly additives used include dispersant BYK-110, defoamer BYK024, and leveling agent DC57.

[0014] Furthermore, the environmentally friendly solvent used is propylene glycol methyl ether (PM).

[0015] Furthermore, the food-grade non-toxic epoxy curing agent uses 890 modified fatty amine drinking water-specific curing agent, with a main agent to curing agent ratio of 3.5:1 to 4:1.

[0016] Furthermore, the inorganic silver-zinc composite antibacterial agent uses food-contact-approved nano-silver-loaded zirconium phosphate inorganic antibacterial powder.

[0017] The present invention discloses a method for preparing a constant-temperature fluorinated modified basalt epoxy ceramic inner wall coating, comprising the following steps:

[0018] Step 1: Under low temperature and low speed stirring conditions, food-grade non-toxic epoxy resin, environmentally friendly solvent, and environmentally friendly additives are mixed evenly to prepare a homogeneous resin base liquid.

[0019] Step 2: Add the isothermal fluorinated modified basalt flakes and high-alumina ceramic powder in sequence, and disperse and grind them at low speed.

[0020] Step 3: Add the inorganic silver-zinc composite antibacterial agent under low temperature conditions and gently stir to mix well.

[0021] Step 4: After grinding to meet the standards, filter to remove impurities and fill to obtain component A. Mix it with food-grade non-toxic curing agent component B at a ratio of 3.5:1 to 4:1 before construction and use.

[0022] The beneficial technical effects of this invention compared to the prior art are as follows:

[0023] This invention employs a food-grade, non-toxic formula, completely eliminating the leaching of heavy metals and secondary water pollution. Through dual modification of basalt flakes, it simultaneously enhances powder compatibility and the coating's water resistance, erosion resistance, and hydrolysis resistance. A low-temperature post-treatment dosing and activation process completely solves the problem of high-temperature inactivation of antibacterial components, achieving long-lasting and stable antibacterial effects. The coating boasts high hardness and strong adhesion, exhibiting excellent compatibility with the underlying primer. It can withstand long-term high-speed water flow through pipelines without leakage or peeling, ensuring long-term cleanliness of the pipeline network and meeting the long-term service requirements of drinking water projects. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the process flow for preparing isothermal fluorinated modified basalt flakes according to the present invention.

[0025] Figure 2 This is a schematic diagram of the mechanism of the basalt flake labyrinth waterproof and antibacterial shielding structure of the present invention. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to specific implementation methods and embodiments.

[0027] The present invention provides a constant-temperature fluorinated modified basalt epoxy ceramic inner wall coating, which is a two-component, non-toxic and environmentally friendly matching system of A and B, with an on-site construction quality mixing ratio of A:B=17:3.

[0028] Component A is prepared from the following raw materials by mass percentage: 50%–60% food-grade non-toxic epoxy resin, 12%–30% constant-temperature fluorinated modified basalt flakes, 10%–15% high-alumina ceramic powder, 2%–4% inorganic silver-zinc composite antibacterial agent, 3%–6% environmentally friendly additives, and the balance of environmentally friendly solvent.

[0029] Component B is a food-grade, non-toxic epoxy curing agent, and the mixing ratio of components A and B during construction is 3.5:1 to 4:1.

[0030] Furthermore, the isothermal fluorination modification process for basalt flakes is as follows: Figure 1 As shown, the surface is first modified by KH-560 silane wet activation, and then by isothermal fluorination surface modification treatment. Specifically:

[0031] Raw material pretreatment: 1000-mesh iron-free basalt flakes are washed with water to remove impurities and dried at 110℃ for later use.

[0032] Step 1: Wet activation modification

[0033] Reaction environment: Ambient temperature and pressure water bath reactor.

[0034] Added materials: 4wt% sodium hydroxide aqueous solution, 1.2% silane KH560 powder.

[0035] Constant temperature: 65℃.

[0036] Stirring reaction time: 2.5h.

[0037] Post-treatment: Wash with deionized water until neutral, then vacuum dry at 110℃ for 2 hours. This generates a large number of hydroxyl active sites on the scale surface, enhancing the binding force of fluorinated grafting.

[0038] Step 2: Isothermal Fluorination Modification

[0039] Reaction environment: Sealed nitrogen-inert reactor.

[0040] Modified agent: ethanol diluted to 1 wt% perfluorodecyltriethoxysilane (PFTS).

[0041] Constant temperature: 70℃.

[0042] Reaction time: 12 hours.

[0043] Post-treatment: Wash three times with anhydrous ethanol, dry at 80℃, and graft a fluoroalkyl hydrophobic layer onto the scale surface to achieve long-lasting water resistance, antibacterial properties, and no water precipitation.

[0044] The basalt flake labyrinth waterproof and antibacterial shielding structure after constant temperature fluorination modification is as follows: Figure 2 As shown, the basalt flakes are 1000-mesh iron-free basalt flakes with a grain size of 8-15 μm, a flake thickness-to-diameter ratio of ≥12:1, and an iron impurity content of ≤50ppm.

[0045] Furthermore, the food-grade non-toxic epoxy resin uses drinking water-specific bisphenol A type E55 epoxy resin, which meets the GB / T17219 hygiene and safety evaluation standard for drinking water transmission and distribution equipment, with no free bisphenol A leaching, and is practically non-toxic.

[0046] Furthermore, the environmentally friendly additives used include dispersant BYK-110, defoamer BYK024, and leveling agent DC57.

[0047] Furthermore, the environmentally friendly solvent used is propylene glycol methyl ether (PM), which is low in toxicity and residue, and no organic matter is released during long-term immersion in water.

[0048] Furthermore, the food-grade non-toxic epoxy curing agent uses 890 modified fatty amine drinking water-specific curing agent, suitable for coating the inner walls of drinking water, and does not leach amines or heavy metals even after long-term immersion in clean water. The ratio of main agent to curing agent is 3.5:1 to 4:1.

[0049] Furthermore, the inorganic silver-zinc composite antibacterial agent uses food-contact-approved nano-silver-loaded zirconium phosphate inorganic antibacterial powder, with a 24-hour antibacterial rate of ≥99.95% and no heavy metal leaching.

[0050] The present invention discloses a constant-temperature fluorinated modified basalt epoxy ceramic inner wall coating, which has a dry film thickness of 80μm~120μm after curing, a pencil hardness of ≥2H, a cross-cut adhesion of ≤1 grade, a 24h antibacterial rate of ≥99.9%, a mildew resistance grade of 0, and complies with the drinking water safety standards of GB 5749 and GB / T 17219, with no harmful substances leaching out.

[0051] The present invention discloses a method for preparing a constant-temperature fluorinated modified basalt epoxy ceramic inner wall coating, comprising the following steps:

[0052] Step 1: Under low temperature and low speed stirring conditions, food-grade non-toxic epoxy resin, environmentally friendly solvent, and environmentally friendly additives are mixed evenly to prepare a homogeneous resin base liquid.

[0053] Step 2: Add the isothermal fluorinated modified basalt flakes and high-alumina ceramic powder in sequence, and disperse and grind them at low speed.

[0054] Step 3: Add the inorganic silver-zinc composite antibacterial agent under low temperature conditions and gently stir to mix well.

[0055] Step 4: After grinding to meet the standards, filter to remove impurities and fill to obtain component A. Mix it with food-grade non-toxic curing agent component B at a ratio of 3.5:1 to 4:1 before construction and use.

[0056] Example 1: Surface coating on the inner wall of a standard drinking water tank.

[0057] 58 parts of food-grade E55 epoxy resin, 24 parts of constant-temperature fluorinated modified 1000-mesh basalt flakes, 3 parts of nano-silver-loaded zirconium phosphate antibacterial powder, 1.0 part of BYK-110 dispersant, 0.4 parts of BYK024 defoamer, 0.6 parts of DC57 leveling agent, and 13 parts of propylene glycol methyl ether solvent; 32 parts of matching 890 food-grade curing agent, with a main agent: curing agent ratio of 3.5:1, and a dry film thickness of 100μm.

[0058] Example 2: High antibacterial, long-lasting, water-resistant drinking water topcoat.

[0059] 54 parts E55 epoxy resin, 26 parts fluorinated modified basalt flakes, 4 parts nano silver-loaded zirconium phosphate antibacterial powder, 1.2 parts BYK-110 dispersant, 0.5 parts BYK024 defoamer, 0.7 parts DC57 leveling agent, 13.6 parts PM solvent; 34 parts curing agent.

[0060] The powder of this invention is modified by silane activation + fluorination at 120℃, with the entire preparation temperature ≤40℃, and the antibacterial components are added at low temperature in the later stage.

[0061] Comparative example: Commercially available ordinary drinking water epoxy topcoat, without fluoride-modified flakes and with short antibacterial duration.

[0062] Performance testing

[0063] Testing standards: GB / T 17219, HG / T 4343, GB / T 21866.

[0064] The test results are shown in Table 1. Example 1: 24h antibacterial rate 99.95%, mildew resistance grade 0, no precipitation or cracking after 180d immersion in clean water, hardness 2H, adhesion grade 1; Example 2: 24h antibacterial rate 99.98%, other properties are better than Example 1; The comparative example showed trace organic matter precipitation after 60d immersion, and the antibacterial rate was less than 90%.

[0065] After curing, the dry film thickness is 80μm~120μm, the pencil hardness is ≥2H, and the cross-cut adhesion is ≤1.

[0066] Table 1 Comparative Test Data of Drinking Water Inner Wall Coating Performance

[0067]

[0068] As can be seen, the finished coating of this invention has a dry film thickness of 100μm, a hardness of 2H, an adhesion grade of 1, a 24-hour antibacterial rate of 99.95%, an anti-mildew grade of 0, and no leaching even after long-term immersion in water. Compared with conventional drinking water coatings, the antibacterial efficiency, water resistance life, and water quality safety are all significantly improved.

[0069] Therefore, this invention employs a dual-modification process of silane activation and 120℃ constant-temperature fluorination of basalt flakes, combined with food-grade non-toxic resin and a low-temperature antibacterial activation lock-in process, to construct a highly safe, long-lasting antibacterial, and water-resistant pipeline inner wall corrosion protection system. The coating of this invention is non-toxic, does not leach, has excellent antibacterial properties, and exhibits strong water resistance and stability, making it widely applicable for long-term anti-corrosion and antibacterial construction of the inner walls of municipal and water conservancy drinking water steel pipelines.

Claims

1. A constant-temperature fluorinated modified basalt epoxy ceramic inner wall coating, characterized in that, It is a two-component, non-toxic, and environmentally friendly supporting system consisting of components A and B; Component A is prepared from the following raw materials by mass percentage: 50%–60% food-grade non-toxic epoxy resin, 12%–30% constant-temperature fluorinated modified basalt flakes, 10%–15% high-alumina ceramic powder, 2%–4% inorganic silver-zinc composite antibacterial agent, 3%–6% environmentally friendly additives, and the balance of environmentally friendly solvent. Component B is a food-grade, non-toxic epoxy curing agent.

2. The isothermal fluorinated modified basalt epoxy ceramic inner wall coating according to claim 1, characterized in that, The isothermal fluorinated modified basalt flakes are 1000 mesh iron-free basalt flakes with a particle size of 8-15 μm, a flake thickness-to-diameter ratio of ≥12:1, and an iron impurity content of ≤50 ppm. The isothermal fluorinated modified basalt flakes are first activated and modified by KH-560 silane wet process, and then subjected to isothermal fluorination surface modification treatment. The KH-560 silane wet activation modification is specifically as follows: 1000-mesh iron-free basalt flakes are screened, washed with water to remove impurities, and dried at 110℃; KH-560 silane coupling agent is added at 1.2% of the powder mass; the reaction is carried out at a constant temperature of 65℃ in a 4wt% sodium hydroxide aqueous solution with stirring for 2 hours; then, the mixture is washed with deionized water until neutral, and vacuum dried at 110℃ for 2 hours. The isothermal fluorination surface modification is specifically performed as follows: ethanol is diluted to 1 wt%, and perfluorodecyltriethoxysilane (PFTS) is added; the reaction is carried out at a constant temperature of 70°C for 12 hours under a closed nitrogen inert environment; then the mixture is washed three times with anhydrous ethanol and dried at a low temperature of 80°C.

3. The isothermal fluorinated modified basalt epoxy ceramic inner wall coating according to claim 1, characterized in that, The food-grade non-toxic epoxy resin used is bisphenol A type E55 epoxy resin specifically for drinking water.

4. The isothermal fluorinated modified basalt epoxy ceramic inner wall coating according to claim 1, characterized in that, The environmentally friendly additives include dispersant BYK-110, defoamer BYK024, and leveling agent DC57.

5. The isothermal fluorinated modified basalt epoxy ceramic inner wall coating according to claim 1, characterized in that, The environmentally friendly solvent used is propylene glycol methyl ether (PM).

6. The isothermal fluorinated modified basalt epoxy ceramic inner wall coating according to claim 1, characterized in that, The food-grade non-toxic epoxy curing agent is 890 modified fatty amine drinking water-specific curing agent, with a main agent to curing agent ratio of 3.5:1 to 4:

1.

7. The isothermal fluorinated modified basalt epoxy ceramic inner wall coating according to claim 1, characterized in that, The inorganic silver-zinc composite antibacterial agent uses food-contact-approved nano-silver-loaded zirconium phosphate inorganic antibacterial powder.

8. The method for preparing the isothermal fluorinated modified basalt epoxy ceramic inner wall coating according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Under low temperature and low speed stirring conditions, food-grade non-toxic epoxy resin, environmentally friendly solvent, and environmentally friendly additives are mixed evenly to prepare a homogeneous resin base liquid. Step 2: Add the isothermal fluorinated modified basalt flakes and high-alumina ceramic powder in sequence, and disperse and grind them at low speed; Step 3: Add the inorganic silver-zinc composite antibacterial agent under low temperature conditions and gently stir to mix well; Step 4: After grinding to meet the standards, filter to remove impurities and fill to obtain component A. Mix it with food-grade non-toxic curing agent component B at a ratio of 3.5:1 to 4:1 before construction and use.

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