Fluorosilicon-modified polymeric oil-water repellent surface layer material and method for producing the same

Abstract

The application provides a fluorosilicon modified geopolymer oil-water repellent surface layer material, which comprises the following components in parts by weight: 80-115 parts of silico-aluminate mineral raw material, 15-25 parts of modified silicone-acrylic emulsion, 15-25 parts of fluorine-containing polymer, 55-70 parts of sodium silicate solution, 25-30 parts of solid caustic alkali, 10-20 parts of deionized water, 2-3 parts of organic fiber, 1.5-2 parts of grinding aid, 0.25-0.3 parts of water reducing agent and 0.1-0.2 parts of silane coupling agent. The application also provides a preparation method of the surface layer material, which comprises the preparation of an organic alkali activator, the preparation of geopolymer powder, the preparation of a fiber-alkali activator mixed solution, the preparation of fluorinated silicon dioxide, the preparation of geopolymer slurry and the curing of the geopolymer surface layer material. The surface layer material can not only effectively solve the problem of strong hydrophilicity and lipophilicity and easy water and oil intrusion, but also ensure the mechanical strength and good impact resistance of the structure, and can be applied to the fields of boat bridge pavement, surface protection of sea-crossing bridge, offshore oil platform and extreme environment building.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of building materials, and particularly relates to a fluorosilicon modified geopolymer oil-water dual-repellent surface layer material and a preparation method thereof. BACKGROUND

[0002] At present, the development of hydrophobic and oleophobic materials has very important value in the fields of building corrosion prevention and mechanical manufacturing. Some relatively extreme environments have higher requirements for the dual-repellent performance and mechanical strength of materials, such as the deck pavement of a ship bridge and offshore oil platforms. These facilities are in the marine environment for a long time, and the sea area where they work may have the problem of oil pollution diffusion, so the dual corrosion factors of water and oil stains need to be considered. In addition, the ship bridge and offshore platform are also carriers of large vehicles and equipment, and the surface of the ship bridge and offshore platform will often have large equipment passing through, so wear and impact will be common. Therefore, how to improve the wear resistance and impact resistance of the surface layer material while ensuring the water and oil dual-repellent performance of the surface layer material has become a focus problem in current research.

[0003] Geopolymer is a three-dimensional network structure inorganic ceramic material, which has excellent mechanical properties and can be used as a coating to protect buildings and machinery. However, geopolymer material belongs to inorganic material and has hydrophilic properties. Water will enter the interior of the material through capillary pores, and some corrosive ions (such as chloride ions and sulfate ions) will also invade, thereby seriously damaging the material itself and even affecting the durability of the structure. On the other hand, when the material is applied in the environment of oil pollution, such as ship bridges, offshore platforms and chemical industry, ordinary geopolymer cannot prevent oil from invading the interior, resulting in the decomposition of the corresponding double salt generated by the reaction of high molecular weight organic acids in oil and hydroxide in cement, causing the material to become soft. In the traditional sense, materials with a surface water contact angle greater than 90° are considered to be hydrophobic materials. Materials with strong hydrophobic properties can generally avoid fogging, achieve surface self-cleaning, and prevent corrosion. However, when the chemical properties of the material surface change to hydrophobic, the material often has affinity with organic molecules in oil, leading to the invasion of oil phase and the destruction of the internal structure. Therefore, it is necessary to develop a dual-repellent modified material that can maintain stability in the environment of water and oil interaction and improve the wear resistance of the material, so as to be suitable for the fields of building corrosion prevention and mechanical manufacturing.

[0004] Traditional oil-repellent and water-repellent processes are mainly based on coating materials. Traditional coatings (such as asphalt-based waterproof coatings and polyurethane waterproof coatings) have high environmental pollution, high cost and adverse effects on human health. Although high-performance environmentally friendly coatings (such as polymer emulsion waterproof coatings) have advantages such as good elasticity, high elongation, non-toxicity and convenient construction, they have relatively poor mechanical properties, wear resistance and aging resistance of the coating film due to the absence of inorganic components, and are prone to fall off.

[0005] Patent application CN113831836A provides a waterproof material for building and its preparation method. This method prepares a high-elastic, high-breathable waterproof material by adding carbon oxide nanotubes, electrospinning and other inorganic and organic polymer nanomaterials. It has good permeability, water resistance, breathability and waterproof effect. However, the impact resistance of this material is limited, the cost is high, the price is expensive, and it is difficult to be widely used. And compared with water, the surface tension of oil is much smaller, and it is easier to wet the solid surface. This material cannot realize water and oil double repellency.

[0006] Chinese patent CN104259073B provides a super-hydrophobic and oleophobic coating and its processing method. A three-layer nano-structured oleophobic and hydrophobic coating is invented, which can be used in oil-containing environments without restriction, can withstand harsh environments with pH of 1-12 for a long time, and has simple process and low cost. However, it is very sensitive to mechanical force, and a certain impact can easily make the material surface lose the double-repellent ability.

[0007] Patent application CN109651855A provides a fluorinated silicon dioxide nanoparticle hydrophobic base and its application. This method develops a fluorinated silicon dioxide nanoparticle hydrophobic agent through sol-gel method, which can be coated on the surface of objects by spin coating and coating method, and has oil-repellent ability. Although this method has the advantages of simple preparation process, low cost, non-toxic and harmless chemical reaction process, etc., it cannot solve the problems of limited adhesion between coating and substrate and poor impact resistance.

[0008] Patent application CN113652156A provides a high water-resistant polymer cement waterproof material. This method uses water-based synthetic resin as film-forming base material and water as dispersion medium to prepare water-based waterproof coating, and adds special hydrophobic raw materials to improve water resistance. Although this method has the advantages of simple preparation process and convenient construction, it also has the problems of poor high and low temperature resistance, insufficient ultraviolet resistance, poor elasticity and breathability, easy aging, and insufficient waterproof time effect.

[0009] In summary, the existing hydrophobic or oleophobic surface layer material still cannot overcome the problems of weak mechanical properties, poor adhesion, and other problems, and is not suitable for building corrosion and mechanical manufacturing fields. If the geopolymer is modified and then used in waterproof and oil-proof engineering through relevant means, not only can the problems of strong hydrophilicity and oleophilicity, easy invasion by water and oil be effectively solved, but also the mechanical strength and impact resistance of the structure can be guaranteed. SUMMARY

[0010] In view of the shortcomings of weak mechanical properties, poor adhesion, easy aging and other shortcomings of the existing hydrophobic and oleophobic surface layer material, the present application provides a fluorine-silicon modified geopolymer oil and water double-repellent surface layer material and its preparation method.

[0011] The technical scheme of the present application is as follows: a fluorosilicon modified polymer oil-water dual-repellent surface layer material includes the following components in parts by weight: 80-115 parts of a silico-aluminate mineral raw material, 15-25 parts of a modified silicone-acrylic emulsion, 15-25 parts of a fluorine-containing polymer, 55-70 parts of a sodium silicate solution, 25-30 parts of solid caustic alkali, 10-20 parts of deionized water, 2-3 parts of organic fiber, 1.5-2 parts of grinding aid, 0.25-0.3 parts of water reducing agent, and 0.1-0.2 parts of silane coupling agent.

[0012] Further, the fluorine-containing polymer includes 8-14 parts of polyvinylidene fluoride-hexafluoropropylene and 7-11 parts of fluorinated silicon dioxide; the fluorinated silicon dioxide is a functionalized nanomaterial obtained by treating nanosilica with perfluorodecyltrimethoxysilane and ethanol; wherein the average particle size of the nanosilica particles is 20 nm, and the purity is greater than 98%.

[0013] Further, the silico-aluminate mineral raw material includes 65-75 parts of metakaolin, 15-25 parts of fly ash, and 10-20 parts of slag.

[0014] Further, the modified silicone-acrylic emulsion contains monomers, emulsifiers, buffers, and initiators; the monomers include at least one of methyl methacrylate, butyl acrylate, and acrylic acid; the emulsifier is a compound of sodium dodecyl sulfate and dodecyl phenol polyoxyethylene ether at a ratio of 1:1 to 3:1; the buffer is sodium bicarbonate, and the initiator is potassium persulfate.

[0015] Further, the sodium silicate solution is a mixed solution of sodium silicate and deionized water, and the water content is 60%-75% by mass fraction; the molar mass ratio of SiO2 to Na2O in the sodium silicate is 3.5-4.5:1.

[0016] Further, the solid caustic alkali includes at least one of sodium hydroxide solid, potassium hydroxide solid, and lithium hydroxide solid.

[0017] Further, the organic fiber includes, but is not limited to, at least one of polyvinyl alcohol fiber, polypropylene fiber, and polyester fiber.

[0018] Further, the water reducing agent includes at least one of calcium lignosulfonate, tannin, amine sulfonate, and sodium polycarboxylate.

[0019] Further, the silane coupling agent has an active ingredient of greater than 95% and includes at least one of gamma-aminopropyl triethoxysilane, gamma-propyl trimethoxysilane, gamma-methacryloyloxypropyl trimethoxysilane, and vinyl trimethoxysilane.

[0020] The application further provides a preparation method of the fluorine-silicon modified geopolymer oil-water double repellent surface layer material.

[0021] S1, preparation of the organic alkali activator: solid caustic soda, sodium silicate solution and modified silicone-acrylate emulsion are mixed and stirred until uniform and clear, then poured into a plastic container and sealed for preservation for 12-24 hours to obtain the organic alkali activator;

[0022] S2, preparation of the geopolymer powder: silicate mineral raw materials, water reducing agent and grinding aid are mixed, stirred and ground for 40-60 minutes to obtain the geopolymer powder;

[0023] S3, preparation of the fiber-alkali activator mixed solution: organic fibers, the organic alkali activator obtained in step S1, silane coupling agent and deionized water are mixed and ultrasonically dispersed for 60-90 minutes at 60-75 Hz to obtain the fiber-alkali activator mixed solution;

[0024] S4, preparation of the fluorinated silicon dioxide: nano-silicon dioxide is added into ethanol and ultrasonically agitated for 10 minutes to uniformly mix, then perfluorodecyltrimethoxysilane is added dropwise under stirring at room temperature, and the stirring is continued for 6 hours, then the suspension is centrifuged at 2000 r / min for 2.5 minutes, and the precipitate filtered out is dried at 65 DEG C for 3 hours to obtain fluorinated silicon dioxide powder;

[0025] S5, preparation of the geopolymer slurry: polyvinylidene fluoride-hexafluoropropylene and the geopolymer powder, the fiber-alkali activator mixed solution and the fluorinated silicon dioxide powder obtained in steps S2-S4 are mixed and stirred at a rotation speed of 600-900 r / min for 15-30 minutes to obtain the geopolymer slurry;

[0026] S6, the geopolymer slurry obtained in step S5 is poured into a mold and cured, first cured in a vacuum drying oven at 20-65 DEG C for 24-48 hours, then demolded and naturally cured at room temperature for 3-14 days to obtain the fluorine-silicon modified geopolymer oil-water double repellent surface layer material.

[0027] The application has the advantages that the geopolymer with organic functional groups is mixed with hydroxide to prepare the alkali activator, so that the organic geopolymer material with excellent waterproof and anti-permeability is formed; the addition of nano-silicon dioxide can improve the micro-pore structure and enhance the compactness of the material; the addition of organic fibers can create surface roughness and fill the micro-pore structure; the combined action of the two can greatly improve the resistance of the material to ion erosion and freeze-thaw cycles.

[0028] Meanwhile, the preparation method has mild reaction conditions in each step, the highest temperature of step S1 is only 85 DEG C, and the steps are simple, and do not need filtering and purification, etc., and are suitable for large-scale industrial production; the waste raw materials such as fly ash, slag and silica ash are combined together, the flow performance and working performance of the material are improved, a green and environment-friendly treatment way is provided for the waste raw materials, and the energy saving and environment protection and sustainable development strategy requirements are met. The surface layer material can not only effectively solve the problems that hydrophilicity and lipophilicity are strong and water and oil are easily invaded, but also guarantee the mechanical strength and good impact resistance of the structure, and can be applied to the fields of boat bridge pavement, surface protection of sea-crossing bridge, offshore oil platform and extreme environment building. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below, obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0030] The principle of the present application is as follows: through a geopolymer reaction process, the modified silicone-acrylate emulsion and the organic functional groups of the fluoropolymer are combined with the inorganic silicate, and finally the organic geopolymer is formed; the addition of the fluoropolymer forms a complex multi-scale hierarchical structure on the surface of the material, and creates the condition of oil-repellent surface; the geopolymer material not only has good mechanical strength and superior bonding performance of the geopolymer, but also can effectively resist water and oil invasion, biological attachment, ion erosion and freeze-thaw damage, and has good mechanical performance and durability.

[0031] The fluorine-silicon modified geopolymer oil and water double-repellent surface layer material of the present application comprises the following components in parts by weight: 80-115 parts of silicate-aluminate mineral raw material, 15-25 parts of modified silicone-acrylate emulsion, 15-25 parts of fluoropolymer, 55-70 parts of sodium silicate solution, 25-30 parts of solid caustic alkali, 10-20 parts of deionized water, 2-3 parts of organic fiber, 1.5-2 parts of grinding aid, 0.25-0.3 parts of water reducing agent and 0.1-0.2 parts of silane coupling agent.

[0032] The silicate-aluminate mineral raw material is preferably a compounded material, comprising 65-75 parts of metakaolin, 15-25 parts of fly ash and 10-20 parts of slag; the solid caustic alkali comprises at least one of sodium hydroxide solid, potassium hydroxide solid and lithium hydroxide solid.

[0033] The modified silicone-acrylic emulsion comprises monomers, emulsifiers, buffers and initiators, the monomers can be at least one of methyl methacrylate (MMA), butyl acrylate (BA) and acrylic acid (AA); the emulsifier is a mixture of sodium dodecyl sulfate (SDS) and dodecyl phenol polyoxyethylene ether (OP-10) in a ratio of 1:1 to 3:1; the buffer and the initiator can be sodium bicarbonate and potassium persulfate.

[0034] The fluorine-containing polymer comprises polyvinylidene fluoride-hexafluoropropylene 8-14 parts and fluorinated silicon dioxide 7-11 parts; wherein the fluorinated silicon dioxide is a functionalized nanomaterial obtained by treating, filtering and drying nanosilica with perfluorodecyltrimethoxysilane and ethanol; comprising: nanosilica 3-4 parts, ethanol 25-30 parts, perfluorodecyltrimethoxysilane 1.5-2 parts; the average particle size of the nanosilica particles is 20 nanometers, and the purity is greater than 98%.

[0035] The sodium silicate solution is a mixed solution of sodium silicate and deionized water, with a water content of 60%-75%, and the molar mass ratio of SiO2 to Na2O is 3.5-4.5:1.

[0036] The silane coupling agent has an effective component of more than 95%, and comprises at least one of γ-aminopropyl triethoxysilane (KH550), γ-propyl trimethoxysilane (KH-560), γ-methacryloyloxypropyl trimethoxysilane (KH-570) and vinyl trimethoxysilane (A171).

[0037] The organic fiber includes but is not limited to at least one of polyvinyl alcohol fiber, polypropylene fiber and polyester fiber.

[0038] The water reducing agent includes but is not limited to at least one of calcium lignosulfonate, tannin, amine sulfonate and sodium polycarboxylate.

[0039] The preparation method of the fluorine-silicon modified geopolymer material, comprising the following steps:

[0040] S1, preparation of an alkali activator: mix solid caustic soda, sodium silicate solution and modified silicone-acrylic emulsion, stir until uniform and clear, pour into a plastic container, seal and store for 12-24 hours to obtain an organic alkali activator;

[0041] S2, preparation of geopolymer powder: mix silicate-aluminate mineral raw material, water reducing agent and grinding aid in proportion, stir and grind for 40-60 minutes to obtain geopolymer powder;

[0042] S3, preparation of a fiber-alkali activator mixed solution: mix organic fiber, the organic alkali activator obtained in step S1, silane coupling agent and deionized water, and disperse by ultrasonic wave at 60-75 Hz for 60-90 minutes to obtain a fiber-alkali activator mixed solution;

[0043] S4, preparation of fluorinated silica: nano-silica was added into ethanol, and ultrasonic oscillation was performed for 10 min to uniformly mix, then perfluorodecyltrimethoxysilane was added dropwise under stirring at room temperature, after continuous stirring for 6 h, the suspension was centrifuged at 2000 r / min for 2.5 min, then the precipitate filtered out was dried at 65°C for 3 h, and finally fluorinated silica powder was obtained;

[0044] S5, preparation of geopolymer slurry: polyvinylidene fluoride-hexafluoropropylene and geopolymer powder obtained in steps S2-S4, fiber-alkali activator mixed solution, and fluorinated silica powder were mixed to obtain fluorine-containing methyl geopolymer slurry by mixing and stirring at a speed of 600-900 r / min for 15-30 min;

[0045] S6, the fluorine-containing methyl geopolymer slurry obtained in step S5 was poured into a mold for curing, first water curing in a vacuum drying oven at 20-65°C for 24-48 h, then demolding, and then natural curing at room temperature for 3-14 days to obtain a fluorine-silicon modified geopolymer oil-water repellent surface layer material.

[0046] The organic groups in the modified silicone-acrylic emulsion in step S3 can be combined with the silica-alumina gel under the action of the silane coupling agent to form an organic-inorganic hybrid network structure; water molecules are more easily invaded into the interior of the material due to their smaller diameter than oil molecules, and the organic-inorganic hybrid network structure is beneficial to reducing the micropores in the interior of the material and blocking the penetration channels of water molecules; at the same time, the network structure can also improve the wear resistance and adhesion to the substrate of the surface layer material; the silane coupling agent can form a combined layer of organic matrix-silane coupling agent-inorganic matrix between the inorganic and organic interfaces due to its reactivity to inorganic substances and the compatibility of the organic functional groups to organic substances, which not only provides more organic hydrophobic groups, but also tightly connects the modified silicone-acrylic emulsion and the silica-alumina gel together; the waterproof material prepared by using an alkali activator containing sodium silicate not only has greatly improved strength, impact resistance and adhesion, but also has excellent performance indicators, weather resistance, water resistance and workability; the addition of an appropriate amount of water reducing agent can effectively reduce the water-cement ratio and further improve the mechanical properties and impermeability of the waterproof material.

[0047] The mixing of metakaolin, slag and fly ash in the silicate mineral helps to improve the micro-pore structure of the material; the addition of slag helps to improve the fluidity of the slurry, on the one hand, the geopolymer powder is fully contacted and reacted, on the other hand, the workability is improved; the addition of organic fibers not only can play a bridging role, improve the viscosity and toughness of the material, reduce the generation of cracks, but also can provide roughness for the surface of the material to enhance its hydrophobic performance. The acrylic groups in the modified silicone-acrylate emulsion can react with the silanol groups of the silane coupling agent to a certain extent, thereby enhancing the compatibility between them and achieving better coating effect.

[0048] However, to be water and oil repellent, only the above-mentioned materials are not enough, and fluorinated silicon dioxide and polyvinylidene hexafluoropropylene also need to be introduced. The particle surface of fluorinated silicon dioxide in step S5 itself has nano-level protrusions, and micro-level network pores can be formed between nano-level fluorinated silicon dioxide and nano silicon dioxide particles. Therefore, the addition of the material not only can improve the pore structure inside the material and block the channel for oil phase invasion, but also can construct multi-level pores with nano silicon dioxide to form a complex multi-scale hierarchical structure (micro-nano double structure) on the surface of the material; a large amount of air exists in the double hierarchical structure pores, and when oil drops fall on the surface of the material, it will be blocked by the air in the pores, thereby being difficult to completely wet the surface. Moreover, due to the presence of perfluorodecyltrimethoxysilane groups, fluorinated silicon dioxide can also reduce the surface free energy of the material.

[0049] The addition of polyvinylidene hexafluoropropylene has three advantages, first, it itself has excellent chemical corrosion resistance, flexibility, weather resistance and impact strength, and poor hydrophilicity, which can work together with organic fibers to greatly enhance the durability and weather resistance of the surface layer material; second, polyvinylidene hexafluoropropylene can wrap the organic groups of fluorinated silicon dioxide particles and modified silicone-acrylate emulsion, prevent them from falling off due to friction or extrusion, protect the integrity of the multi-scale rough structure and maintain the low surface energy of the material; third, polyvinylidene hexafluoropropylene can combine with the silica-alumina gel under the action of the silane coupling agent to form an organic-inorganic hybrid network structure, further reduce the porosity of the material, and improve the wear resistance and adhesion of the material.

[0050] The scheme and technical effects of the present application are further illustrated by specific examples.

[0051] Example 1

[0052] The fluorine-silicon modified geopolymer oil and water repellent surface layer material comprises the following components in parts by weight: metakaolin 65 parts, fly ash 15 parts, slag 16 parts, sodium hydroxide solid 25 parts, sodium silicate solution 60 parts, modified silicone-acrylate emulsion solution 15 parts, gamma-aminopropyl triethoxysilane (KH550) 0.1 part, polypropylene fiber 2 parts, deionized water 10 parts, grinding aid 1.6 parts, water reducing agent 0.3 parts, polyvinylidene fluoride-hexafluoropropylene 7 parts, nano silicon dioxide 3.5 parts, perfluorodecyltrimethoxysilane 2 parts, and ethanol 28 parts.

[0053] The water content of the sodium silicate solution is 60%, and the molar mass ratio of SiO2 to Na2O is 4.5:1; the average diameter of the polypropylene fiber is 15 μm, and the length is 7 mm.

[0054] The preparation method of the material comprises the following steps:

[0055] S1, mix the sodium hydroxide solid, the sodium silicate solution and the modified silicone-acrylate emulsion solution, stir until uniform and clear, pour into a plastic container, seal and store for 24 h, to obtain an organic alkali activator;

[0056] S2, mix the metakaolin, fly ash, slag and grinding aid in proportion, stir and grind for 40 min, to obtain a geopolymer powder;

[0057] S3, mix the gamma-aminopropyl triethoxysilane (KH550), the polypropylene fiber, the organic alkali activator obtained in step S1 and the deionized water, and then disperse by 60 Hz ultrasonic for 60 min, to obtain a fiber solution;

[0058] S4, preparation of fluorinated silicon dioxide: add 3.5 parts of nano silicon dioxide powder into 28 parts of ethanol, ultrasonically oscillate for 10 min, mix uniformly, then add 2 parts of perfluorodecyltrimethoxysilane dropwise under stirring at room temperature, continue stirring for 6 h, then centrifuge the suspension at 2000 r / min for 2.5 min, then dry the precipitate filtered out at 65℃ for 3 h, to obtain fluorinated silicon dioxide powder.

[0059] S5, mix 7 parts of polyvinylidene fluoride-hexafluoropropylene, the geopolymer powder obtained in steps S2-S4, the fiber solution and the fluorinated silicon dioxide powder, and then mix and stir at a speed of 700 r / min for 15 min, to obtain an organic geopolymer slurry;

[0060] S6, pour the geopolymer slurry obtained in step S5 into a mold, and then cure in a curing box at 25℃ for 48 h, after demolding, naturally cure at room temperature for 7 days, to obtain the final fluorine-silicon modified geopolymer oil and water repellent surface layer material.

[0061] Example 2

[0062] The fluorine-silicon modified geopolymer oil-water repellent surface layer material comprises the following components in parts by weight: metakaolin 70 parts, fly ash 15 parts, slag 10 parts, potassium hydroxide solid 25 parts, sodium silicate solution 60 parts, modified silicone-acrylate emulsion solution 20 parts, gamma-propyltrimethoxysilane (KH-560) 0.2 parts, polyvinyl alcohol fiber 2.55 parts, deionized water 10 parts, grinding aid 2 parts, water reducing agent 0.25 parts, polyvinylidene fluoride-hexafluoropropylene 8 parts, nano-silicon dioxide 3 parts, perfluorodecyltrimethoxysilane 1.5 parts, and ethanol 27 parts.

[0063] The water content of the sodium silicate solution is 60%, and the molar mass ratio of SiO2 to Na2O is 3.5:1; the average diameter of the polyvinyl alcohol fiber is 60 μm, and the length is 8 mm.

[0064] The preparation method of the material comprises the following steps:

[0065] S1, mix the potassium hydroxide solid, the sodium silicate solution and the modified silicone-acrylate emulsion solution, stir until uniform and clear, pour into a plastic container, seal and store for 24 h, and obtain an organic alkali activator;

[0066] S2, mix the metakaolin, fly ash, slag and grinding aid in proportion, stir and grind for 40 min, and obtain geopolymer powder;

[0067] S3, mix the gamma-propyltrimethoxysilane (KH-560), polyvinyl alcohol fiber, organic alkali activator obtained in step S1 and deionized water, and disperse by ultrasonic vibration at 75 Hz for 60 min, and obtain a fiber solution;

[0068] S4, preparation of fluorinated silicon dioxide: add 3 parts of nano-silicon dioxide powder to 27 parts of ethanol, ultrasonically oscillate for 10 min to mix uniformly, then add 1.5 parts of perfluorodecyltrimethoxysilane dropwise under stirring at room temperature, continue stirring for 6 h, then centrifuge the suspension at 2000 r / min for 2.5 min, then dry the precipitate filtered out at 65℃ for 3 h, and finally obtain fluorinated silicon dioxide powder.

[0069] S5, mix 8 parts of polyvinylidene fluoride-hexafluoropropylene, geopolymer powder obtained in steps S2-S4, fiber solution and fluorinated silicon dioxide powder, and mix and stir at a speed of 900 r / min for 25 min, and obtain an organic geopolymer slurry;

[0070] S6, pour the geopolymer slurry obtained in step S5 into a mold for curing, first store in a curing box at 25℃ for 48 h, then perform demolding, and then naturally cure at room temperature for 14 days, and obtain the final fluorine-silicon modified geopolymer oil-water repellent surface layer material.

[0071] Example 3

[0072] The fluorosilicon modified geopolymer oil and water repellent surface layer material comprises the following components in parts by weight: metakaolin 65 parts, fly ash 15 parts, slag 10 parts, lithium hydroxide solid 25 parts, sodium silicate solution 55 parts, modified silicone-acrylate emulsion solution 15 parts, gamma-methacryloxypropyltrimethoxysilane (KH-570) 0.2 parts, polyester fiber 2 parts, deionized water 11 parts, grinding aid 1.5 parts, polyvinylidene fluoride-hexafluoropropylene 6 parts, nano-silicon dioxide 4 parts, perfluorodecyltrimethoxysilane 2 parts, and ethanol 26 parts.

[0073] The water content of the sodium silicate solution is 60%, and the molar mass ratio of SiO2 to Na2O is 4:1; the water content of the modified silicone-acrylate emulsion solution is 70%; the average diameter of the polyester fiber is 45 μm, and the length is 10 mm.

[0074] The preparation method of the material comprises the following steps:

[0075] S1, mixing the lithium hydroxide solid, the sodium silicate solution and the modified silicone-acrylate emulsion solution, stirring until uniform and clear, pouring into a plastic container and sealing for 24 h to obtain an organic alkali activator;

[0076] S2, mixing the metakaolin, fly ash, slag and grinding aid in proportion, stirring and grinding for 40 min to obtain geopolymer powder;

[0077] S3, mixing the gamma-methacryloxypropyltrimethoxysilane (KH-570), the polyester fiber, the organic alkali activator obtained in step S1 and the deionized water, and then ultrasonic dispersing for 60 min at 70 Hz to obtain a fiber solution;

[0078] S4, preparation of fluorinated silicon dioxide: adding 4 parts of nano-silicon dioxide powder into 26 parts of ethanol, ultrasonic oscillation for 10 min to mix uniformly, then adding 2 parts of perfluorodecyltrimethoxysilane dropwise under stirring at room temperature, continuing to stir for 6 h, then centrifuging the suspension at 2000 r / min for 2.5 min, then drying the precipitate filtered out at 65°C for 3 h to obtain fluorinated silicon dioxide powder.

[0079] S5, mixing 6 parts of polyvinylidene fluoride-hexafluoropropylene, the geopolymer powder obtained in steps S2-S4, the fiber solution and the fluorinated silicon dioxide powder, and then stirring at a speed of 600 r / min for 30 min to obtain an organic geopolymer slurry;

[0080] S6, pouring the geopolymer slurry obtained in step S5 into a mold for curing, first curing in a curing box at 30°C for 48 h, then demolding, and then naturally curing at room temperature for 28 days to obtain the final fluorosilicon modified geopolymer oil and water repellent surface layer material.

[0081] Comparative Example 1

[0082] The modified geopolymer surface layer material includes the following components by weight fraction: metakaolin 65 parts, fly ash 15 parts, slag 10 parts, potassium hydroxide solid 25 parts, sodium silicate solution 65 parts, gamma-methacryloxypropyltrimethoxysilane (KH-570) 0.1 parts, polypropylene fiber 3 parts, deionized water 15 parts, grinding aid 1.65 parts, polyvinylidene hexafluoropropylene 8 parts, nano-silicon dioxide 4 parts, perfluorodecyltrimethoxysilane 2 parts, and ethanol 28 parts.

[0083] The water content of the sodium silicate solution is 65%, and the molar mass ratio of SiO2 to Na2O is 4:1; the water content of the modified silicone-acrylic emulsion solution is 65%; the average diameter of the polypropylene fiber is 25 μm, and the length is 7 mm.

[0084] The material preparation method includes the following steps:

[0085] S1, after mixing lithium hydroxide solid and sodium silicate solution, stirring until uniform and clear, pouring into a plastic container and sealing for 24 h to obtain an alkali activator;

[0086] S2, metakaolin, fly ash, slag and grinding aid are mixed and ground in proportion for 40 min to obtain geopolymer powder;

[0087] S3, gamma-methacryloxypropyltrimethoxysilane (KH-570), polypropylene fiber, alkali activator obtained in step S1 and deionized water are mixed and dispersed by 70 Hz ultrasonic for 60 min to obtain a fiber solution;

[0088] S4, preparation of fluorinated silicon dioxide: 4 parts of nano-silicon dioxide powder are added to 28 parts of ethanol, ultrasonic oscillation for 10 min to mix uniformly, then 2 parts of perfluorodecyltrimethoxysilane are added dropwise under stirring at room temperature, and the stirring is continued for 6 h. Then the suspension is centrifuged at 2000 r / min for 2.5 min, and the precipitate filtered out is dried at 65°C for 3 h to obtain fluorinated silicon dioxide powder.

[0089] S5, 8 parts of polyvinylidene hexafluoropropylene, geopolymer powder obtained in steps S2-S4, fiber solution, and fluorinated silicon dioxide powder are mixed and stirred at a speed of 800 r / min for 20 min to obtain an organic geopolymer slurry;

[0090] S6, the geopolymer slurry obtained in step S5 is poured into a mold and cured, first in a curing box at 40°C for 48 h, then after demolding, it is naturally cured at room temperature for 21 days to obtain the final modified geopolymer surface layer material.

[0091] Comparative Example 2

[0092] The modified geopolymer surface layer material comprises the following components by weight fraction: metakaolin 65 parts, fly ash 20 parts, slag 15 parts, lithium hydroxide solid 30 parts, sodium silicate solution 55 parts, modified silicone-acrylate emulsion solution 15 parts, gamma-aminopropyl triethoxysilane (KH550) 0.2 parts, deionized water 13 parts, grinding aid 1.5 parts, polyvinylidene fluoride-hexafluoropropylene 6.5 parts, nano-silicon dioxide 4 parts, perfluorodecyltrimethoxysilane 1.5 parts, and ethanol 30 parts.

[0093] The water content of the sodium silicate solution is 60%, and the molar mass ratio of SiO2 to Na2O is 4.5:1; the water content of the modified silicone-acrylate emulsion solution is 60%.

[0094] The preparation method of the material comprises the following steps:

[0095] S1, mix the lithium hydroxide solid, sodium silicate solution and modified silicone-acrylate emulsion, stir until uniform and clear, pour into a plastic container and seal for 24 h to obtain an organic alkali activator;

[0096] S2, mix metakaolin, fly ash, slag and grinding aid in proportion, stir and grind for 40 min to obtain geopolymer powder;

[0097] S3, mix gamma-aminopropyl triethoxysilane (KH550), the organic alkali activator obtained in step S1 and deionized water, and then disperse by ultrasonic at 65 Hz for 60 min to obtain a defiber solution;

[0098] S4, preparation of fluorinated silicon dioxide: add 4 parts of nano-silicon dioxide powder to 30 parts of ethanol, ultrasonic oscillation for 10 min to mix uniformly, then add 1.5 parts of perfluorodecyltrimethoxysilane dropwise under stirring at room temperature, continue stirring for 6 h, then centrifuge the suspension at 2000 r / min for 2.5 min, then dry the precipitate filtered out at 65°C for 3 h to obtain fluorinated silicon dioxide powder.

[0099] S5, mix 6.5 parts of polyvinylidene fluoride-hexafluoropropylene, geopolymer powder obtained in steps S2-S4, defiber solution and fluorinated silicon dioxide powder, and stir at a speed of 700 r / min for 20 min to obtain an organic geopolymer slurry;

[0100] S6, pour the geopolymer slurry obtained in step S5 into a mold and cure, first in a curing box at 35°C for 36 h, then after demolding, naturally cure at room temperature for 14 days to obtain the final modified geopolymer surface layer material.

[0101] Comparative Example 3

[0102] The modified geopolymer surface layer material comprises the following components by weight fraction: metakaolin 65 parts, fly ash 20 parts, slag 10 parts, sodium hydroxide solid 30 parts, sodium silicate solution 55 parts, modified silicone-acrylate emulsion solution 15 parts, gamma-aminopropyl triethoxysilane (KH550) 0.2 parts, polypropylene fiber 2.55 parts, deionized water 15 parts, grinding aid 2 parts, polyvinylidene fluoride-hexafluoropropylene 4 parts, nano-silicon dioxide 0.5 parts, perfluorodecyltrimethoxysilane 1.5 parts, and ethanol 29 parts.

[0103] The water content of the sodium silicate solution is 60%, and the molar mass ratio of SiO2 to Na2O is 4.5:1; the water content of the modified silicone-acrylate emulsion solution is 65%; the average diameter of the polypropylene fiber is 20μm, and the length is 6mm.

[0104] The material preparation method comprises the following steps:

[0105] S1, mix the sodium hydroxide solid, sodium silicate solution and modified silicone-acrylate emulsion, stir until uniform and clear, pour into a plastic container and seal for 24h to obtain an alkali activator;

[0106] S2, mix the metakaolin, fly ash, slag and grinding aid in proportion, stir and grind for 40min to obtain a geopolymer powder;

[0107] S3, mix the gamma-aminopropyl triethoxysilane (KH550), polypropylene fiber, alkali activator obtained in step S1 and deionized water, then disperse by 70Hz ultrasonic for 60min to obtain a fiber solution;

[0108] S4, preparation of fluorinated silicon dioxide: add 0.5 parts of nano-silicon dioxide powder to 29 parts of ethanol, ultrasonically shake for 10min to mix uniformly, then add 1.5 parts of perfluorodecyltrimethoxysilane dropwise under stirring at room temperature, continue stirring for 6h, then centrifuge the suspension at 2000r / min for 2.5min, then dry the precipitate filtered out at 65℃ for 3h to obtain fluorinated silicon dioxide powder.

[0109] S5, mix 4 parts of polyvinylidene fluoride-hexafluoropropylene, geopolymer powder obtained in steps S2-S4, fiber solution and fluorinated silicon dioxide powder, mix and stir at a speed of 800r / min for 15min to obtain an organic geopolymer slurry;

[0110] S6, pour the geopolymer slurry obtained in step S5 into a mold and cure, first in a curing box at 30℃ for 48h, then after demolding, naturally cure at room temperature for 21 days to obtain the final modified geopolymer surface layer material.

[0111] In order to verify the mechanical properties and corrosion resistance of the geopolymer surface layer material of the present application, viscosity, compressive strength, flexural strength, contact angle, water absorption and impermeability tests are carried out, and the specific methods and results are as follows:

[0112] ①Viscosity test: the fluorosilicon modified geopolymer oil and water repellent surface layer material prepared in the examples and comparative examples is taken as the test sample, and the viscosity of the just mixed slurry is determined by NDJ-8S digital viscosity tester.

[0113] ②Mechanical strength test: the fluorosilicon modified geopolymer oil and water repellent surface layer material prepared in the examples and comparative examples is taken as the test sample, and its compressive strength and flexural strength are tested according to GB / T 17671-1999 "Cement mortar strength test method (ISO method)".

[0114] ③Contact angle test: the fluorosilicon modified geopolymer oil and water repellent surface layer material prepared in the examples and comparative examples is taken as the test sample, and after natural drying, it is cut open to test the hydrophobic and oleophobic contact angles of its surface and interior, respectively.

[0115] ④Impermeability test: the fluorosilicon modified geopolymer oil and water repellent surface layer material prepared in the examples and comparative examples is taken as the sample, and according to T0568-2005 "Cement concrete impermeability test method", the sample is placed on the permeameter, the water pressure starts from 0.1 MPa, and increases by 0.1 MPa every 8 hours, until 3 out of 6 test pieces show water seepage, and the water pressure at this time is recorded, and the test is stopped. When the pressure reaches the design impermeability level, and after 8 hours, the third test piece still does not seep water, indicating that the concrete has met the design requirements, and the test can be stopped.

[0116] Table 1, test results of fluorosilicon modified geopolymer oil and water repellent surface layer material

[0117]

[0118]

[0119] The test results of examples 1-3 show that the fluorosilicon modified geopolymer oil and water repellent surface layer material of the present application has a compressive strength greater than 45 MPa and a viscosity greater than 12500 MPa·s. Under the combined action of raw materials, nano-particle materials and organic fibers, the material has high mechanical strength; the surface of the material is hydrophobic, the contact angle of water droplets and oil droplets is greater than 145°, and the interior also has good hydrophobic performance, the contact angle is greater than 140°, indicating that the material has been well modified by hydrophobicity under the action of nano-particle materials and organic fibers, and has strong impermeability, with an impermeability level of P12, indicating that the material can be applied to most engineering environments.

[0120] The test results of Comparative Example 1 show that for the waterproof material without adding modified silicone-acrylate emulsion, the surface and internal hydrophobic angle is less than 55°, the rolling angle is close to 15°, and the impermeability grade is only P6, which barely meets the grade requirement of impermeable concrete P6. This shows that the geopolymer has capillary pores inside without modification, which is easily permeated by water, and the surface hydrophobicity is greatly reduced due to the lack of hydrophobic groups provided by the modified silicone-acrylate emulsion; the modified silicone-acrylate emulsion can significantly improve the hydrophobicity of the material; although it can weaken the strength of the waterproof material by about 10%, in general, it is indispensable to the waterproof performance of the material itself. At the same time, it can be seen from the decrease of about 15% in oil-repellent contact angle that although the modified silicone-acrylate emulsion has little effect on the oil-repellent performance of the material, it can form a small amount of micron-level protrusions on the surface of the material, which has a certain positive effect on the construction of nano-micro dual structure.

[0121] The test results of Comparative Example 2 show that for the fluorosilicon modified geopolymer oil-water dual-repellent surface layer material without adding organic fibers, the viscosity decreases by about 45%, the strength decreases by about 33%, the oil-repellent and water-repellent contact angles both decrease by about 15%, and the maximum impermeable water pressure decreases by about 30%. This shows that the organic fibers not only increase the viscosity of the material and improve its mechanical properties, but also inhibit the generation of pores, increase the density and roughness of the material surface, and thus improve the hydrophobic and oil-repellent performance of the material.

[0122] The test results of Comparative Example 3 show that for the fluorosilicon modified geopolymer oil-water dual-repellent surface layer material with only 0.5 parts of nano-silicon dioxide added, the compressive strength and shear strength decrease by about 15% and 7% respectively, the water droplet contact angle decreases slightly, the oil droplet contact angle decreases by about 60%, and the maximum impermeable water pressure decreases by about 15%. This shows that the nano-micro dual structure provided by nano-silicon dioxide is of great significance to the oil-repellent performance of the material, and can improve the hydrophobicity of the material; at the same time, the reduction of polyvinylidene hexafluoropropylene leads to a decrease of about 15% in the strength of the material, which shows that the flexibility, impact resistance and high strength of polyvinylidene hexafluoropropylene can play an important role in the material.

[0123] The above is only a preferred embodiment of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application, and any skilled person in the art can make some changes or modifications to the above-mentioned technical content without departing from the scope of the technical solution of the present application to obtain equivalent embodiments with equivalent changes. Any simple modification, equivalent change and modification of the above embodiments made in accordance with the technical essence of the present application are still within the scope of the present application.

Claims

1. A fluorosilicon-modified polymeric oil-water dual-repellent surface layer material, characterized by, By weight parts including the following components: silicate mineral raw material 80-115 parts, modified silicone acrylic emulsion 15-25 parts, fluorine-containing polymer 15-25 parts, sodium silicate solution 55-70 parts, solid caustic alkali 25-30 parts, deionized water 10-20 parts, organic fiber 2-3 parts, grinding aid 1.5-2 parts, water reducing agent 0.25-0.3 parts, silane coupling agent 0.1-0.2 parts; the fluorine-containing polymer includes polyvinylidene fluoride-hexafluoropropylene 8-14 parts and fluorinated silicon dioxide 7-11 parts; the fluorinated silicon dioxide is a functionalized nanomaterial after treating nanosilica with perfluorodecyltrimethoxysilane and ethanol; wherein the average particle size of the nanosilica is 20 nm, and the purity is greater than 98%; the silicate mineral raw material includes metakaolin 65-75 parts, fly ash 15-25 parts, and slag 10-20 parts.

2. The fluorosilicon-modified polymeric oil-water dual-repellent surface coating material according to claim 1, characterized in that: The modified silicone acrylic emulsion comprises monomers, emulsifiers, buffers and initiators, the monomers including at least one of methyl methacrylate, butyl acrylate and acrylic acid; the emulsifier is a compound of sodium dodecyl sulfate and dodecyl phenol polyoxyethylene ether at a ratio of 1:1 to 3:1; the buffer is sodium bicarbonate, and the initiator is potassium persulfate.

3. The fluorosilicon-modified polymeric oil-water dual-repellent surface coating material according to claim 1, characterized in that: The sodium silicate solution is a mixed solution of sodium silicate and deionized water, and the water content is 60%-75% by mass fraction; the molar mass ratio of SiO2 to Na2O in the sodium silicate is 3.5-4.5:

1.

4. The fluorosilicon-modified polymeric oil-water dual-repellent surface coating material according to claim 1, characterized in that: The solid caustic alkali includes at least one of sodium hydroxide solid, potassium hydroxide solid and lithium hydroxide solid.

5. The fluorosilicon-modified polymeric oil-water dual-repellent surface coating material according to claim 1, characterized in that: The organic fiber includes at least one of polyvinyl alcohol fiber, polypropylene fiber and polyester fiber.

6. The fluorosilicon-modified polymeric oil-water dual-repellent surface coating material according to claim 1, wherein The water reducing agent includes at least one of calcium lignosulfonate, tannin, amine sulfonate and sodium polycarboxylate.

7. The fluorosilicon-modified polymeric oil-water dual-repellent surface coating material according to claim 1, wherein The effective component of the silane coupling agent is greater than 95%, and includes at least one of γ-aminopropyl triethoxysilane, γ-propyl trimethoxysilane, γ-methacryloyloxy propyl trimethoxysilane and vinyl trimethoxysilane.

8. A method for producing a fluorosilicone-modified geopolymer oil-and-water repellent coating material, for producing the fluorosilicone-modified geopolymer oil-and-water repellent coating material according to any one of claims 1 to 7, characterized by, The method comprises the following steps: S1, preparation of an organic alkali activator: mixing the solid caustic alkali, the sodium silicate solution and the modified silicone acrylic emulsion, stirring until uniform and clear, and sealing and storing for 12-24 hours to obtain the organic alkali activator; S2, preparation of a geopolymer powder: mixing and grinding the silicate mineral raw material, the water reducing agent and the grinding aid for 40-60 minutes to obtain the geopolymer powder; S3, preparation of a fiber-alkali activator mixed solution: mixing the organic fiber, the organic alkali activator obtained in step S1, the silane coupling agent and the deionized water, and ultrasonically dispersing for 60-90 minutes at 60-75 Hz to obtain the fiber-alkali activator mixed solution; S4, preparation of fluorinated silicon dioxide: adding nanosilica into ethanol, ultrasonically oscillating for 10 minutes to uniformly mix, then adding perfluorodecyltrimethoxysilane drop by drop under stirring at room temperature, continuously stirring for 6 hours, then centrifuging the suspension at 2000 r / min for 2.5 minutes, then drying the precipitate filtered out at 65°C for 3 hours to finally obtain fluorinated silicon dioxide powder; S5, preparation of geopolymer slurry: polyvinylidene fluoride-hexafluoropropylene mixed and geopolymer powder obtained in steps S2-S4, fiber-alkali activator mixed solution, fluorinated silica powder were mixed at a speed of 600-900 r / min for 15-30 min to obtain a geopolymer slurry; S6, the geopolymer slurry obtained in step S5 was poured into a mold for curing, first water curing in a vacuum drying oven at 20-65°C for 24-48h, after demolding treatment, natural curing at room temperature for 3-14 days to obtain a fluorosilicon modified geopolymer oil and water repellent surface layer material.

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