Conductive titanium dioxide as well as preparation method and application thereof

Abstract

The invention relates to the technical field of pigment and filler preparation, and discloses conductive titanium dioxide as well as a preparation method and application thereof. The preparation method of the conductive titanium dioxide comprises the following steps: step 1, taking tantalum ethoxide, titanium tetraisopropoxide, isopropanol and a glycollic acid aqueous solution as raw materials, and reacting to prepare doped modified titanium dioxide; 2, coating the doped modified titanium dioxide with an organic monomer to obtain organic modified titanium dioxide; and step 3, coating the organic modified titanium dioxide with a metal oxide to obtain the conductive titanium dioxide. The conductive titanium dioxide disclosed by the invention not only has excellent conductivity and weather resistance, but also has the advantages of small particle size and easiness in dispersion, has very good formula applicability, and can be used in conductive coatings.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pigment preparation, in particular to a conductive titanium white powder and a preparation method and application thereof. BACKGROUND

[0002] Titanium white powder has high whiteness, hiding power, opacity and brightness, and is one of the inorganic white pigments with the best application effect, and is known as the "King of inorganic white pigments", which can be used in plastic, paint, water-based paint, rubber, ink, color master batch and decorative paper and many other fields.

[0003] At present, the preparation process of conductive paint is relatively mature, which is widely used in static elimination, and the conductive paint has the advantages of simple operation, less construction process and low cost. The main role of titanium white powder in general conductive paint is to improve the mechanical strength, optical performance and rheological performance of the paint, but titanium white powder is poor in improving the conductive performance of the paint, so the research on conductive titanium white powder is put forward.

[0004] For example, Chinese patent CN111040474B discloses a conductive titanium white powder and a preparation method, which solves the problem of poor conductivity of titanium white powder, but titanium dioxide has photochemical activity and poor weather resistance, and will gradually lose gloss and hiding power under light and climate change. Therefore, it is also important to improve the weather resistance of titanium white powder. SUMMARY

[0005] In order to solve the above technical problems, the present application provides a preparation method of conductive titanium white powder, comprising the following steps: Step one, using ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol and aqueous glycolic acid as raw materials, reacting to prepare doped modified titanium dioxide; Step two, coating the doped modified titanium dioxide with organic monomers to obtain organic modified titanium dioxide; Step three, coating the organic modified titanium dioxide with metal oxides to obtain conductive titanium white powder.

[0006] Preferably, in step one, the volume ratio of ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol and aqueous glycolic acid is (0.22-0.3):5:5:50; the average particle size of the doped modified titanium dioxide is 170nm.

[0007] Preferably, in step one, the reaction conditions are as follows: first stirring at a speed of 500r / min at 78-82℃ for 1.5-2.5h, and then hydrothermal reaction at a temperature of 195-205℃ and a pressure of 1.6MPa for 5-7h; In the above process, the modified rutile titanium dioxide containing metal tantalum is obtained by a traditional hydrothermal method, using tantalum ethoxide and titanium tetraisopropoxide as tantalum source and titanium source, isopropanol as solvent, and glycolic acid as an assistant to promote the formation of rutile titanium dioxide. Compared with anatase titanium dioxide, the rutile titanium dioxide has better stability and weather resistance, and the doping of tantalum improves the conductivity of the rutile titanium dioxide.

[0008] Preferably, in the step two, the preparation method of the organic modified titanium dioxide specifically comprises the following steps: The doped modified titanium dioxide is added into dimethylformamide and ultrasonically treated, then an organic monomer is added, and stirred at 23-28°C for 40-60 min, and then heated to 75-85°C, and ammonium persulfate is added, and stirred for 5-7 h, and then purified to obtain the organic modified titanium dioxide; wherein the mass ratio of the doped modified titanium dioxide, dimethylformamide, organic monomer, and ammonium persulfate is (5-9):(200-300):(6.6-17.2):(0.1-0.2). In the above process, the β-keto ester group in the organic monomer can coordinate with the metal ions in the doped modified titanium dioxide, and then under the initiation of ammonium persulfate, the carbon-carbon double bond and the thiophene part can both undergo self-polymerization, so as to form a dense and firm conductive organic layer on the surface of the doped modified titanium dioxide, which on the one hand improves the conductivity of the doped modified titanium dioxide, and on the other hand, coats the doped modified titanium dioxide to prevent its agglomeration, reduces the particle size, and reduces the photoactivity of the doped modified titanium dioxide, thereby improving the conductivity, dispersibility, and weather resistance of the doped modified titanium dioxide.

[0009] Preferably, the organic monomer in the step two is prepared by the following steps: In step S1, the intermediate product A, 1-amino-3-buten-2-ol, and ethanol are mixed in a mass ratio of (2.4-3.6):(1.3-2.5):(80-100), stirred until uniform, heated to 66-74°C, and stirred for 2-4 h, and then purified to obtain the intermediate product B. In step S2, the thienyl compound and ethanol are mixed in a mass ratio of (2.7-4):(20-30) to obtain a thienyl compound dispersion liquid; the intermediate product B and ethanol are mixed in a mass ratio of (4.2-6.2):(60-80), and the thienyl compound dispersion liquid is added dropwise in an ice water bath, and then reacted at 0°C for 2 h, and then reacted at 23-28°C for 3.5-4.5 h, and then purified to obtain the organic monomer.

[0010] Further, the intermediate product A in the step S1 is prepared by the following steps: Acetoacetylmethyl ethyl acrylate is added into ethanol, stirred, 3-mercapto-2-methyl-pentanal, azobisisobutyronitrile are added, heated to 60-70℃, stirred for 3-5h, purified to obtain intermediate product A; wherein, the mass ratio of acetoacetylmethyl ethyl acrylate, ethanol, 3-mercapto-2-methyl-pentanal, azobisisobutyronitrile is (2.5-4.5):(80-100):(1.3-2.6):(0.03-0.05).

[0011] Further, the thienyl compound in the step S2 is prepared by the following steps: 2,5-dicarboxylic acid-3,4-vinylenedithiophene, thionyl chloride are mixed in a mass ratio of (2.3-3.5):(5.9-11.8), stirred for 3-4h, then reacted at 76-84℃ for 20-30min, purified to obtain the thienyl compound; In the above process, acetoacetylmethyl ethyl acrylate contains β-keto ester group, which can rapidly coordinate with metal ions to form strong coordination bond, acetoacetylmethyl ethyl acrylate is combined with 3-mercapto-2-methyl-pentanal through the reaction between mercapto and carbon-carbon double bond to obtain intermediate product A containing β-keto ester group and aldehyde group; intermediate product A is combined with 1-amino-3-buten-2-ol through Schiff base reaction to obtain intermediate product B containing β-keto ester group, hydroxyl group and carbon-carbon double bond; next, 2,5-dicarboxylic acid-3,4-vinylenedithiophene, thionyl chloride are reacted to convert the carboxyl group of 2,5-dicarboxylic acid-3,4-vinylenedithiophene into acyl chloride to form thienyl compound, which is well known to be able to polymerize to form polythiophene with excellent conductivity; finally, the acyl chloride of thienyl compound reacts with the hydroxyl group of intermediate product B to obtain organic monomer, which contains β-keto ester group, carbon-carbon double bond and thienyl group.

[0012] Preferably, in the step three, the preparation method of the conductive titanium white powder specifically comprises: Stannum chloride pentahydrate is added into ethanol to prepare solution A; zinc chloride, citric acid are added into water to prepare solution B; solution A is added into solution B, stirred, then organic modified titanium dioxide is added, 4mol / L sodium hydroxide aqueous solution is added, ultrasonic treatment is carried out for 1-2h, filtration, washing, drying, the dried product is calcined at 590-610℃ for 100-150min in argon atmosphere to obtain conductive titanium white powder; wherein, the mass ratio of stannum chloride pentahydrate, zinc chloride, citric acid, organic modified titanium dioxide, 4mol / L sodium hydroxide aqueous solution is (1.4-2.8):(0.55-1.1):(0.84-1.68):(12-20):(55-110); In the above process, tin chloride pentahydrate and zinc chloride are used as metal precursors, citric acid is used as a reducing agent, and a zinc oxide doped tin oxide metal oxide layer is formed on the surface of the organic modified titanium dioxide. The beta-keto ester groups on the surface of the organic modified titanium dioxide are coordinated with zinc ions and tin ions, providing growth sites for the in-situ generation of zinc oxide and tin oxide. The strong coordination between the metal and the beta-keto ester group makes the metal oxide layer firmly coated on the surface of the organic modified titanium dioxide. The tin oxide in the metal oxide layer has excellent electrical conductivity. After doping with zinc oxide, not only the electrical conductivity of the metal oxide layer is improved, but also the weather resistance of the metal oxide layer is improved.

[0013] The conductive titanium white powder prepared by the preparation method of the conductive titanium white powder.

[0014] The application of the conductive titanium white powder in conductive coatings.

[0015] Compared with the prior art, the conductive titanium white powder has the following advantages: 1. The conductive titanium white powder is obtained by coating an organic layer and a metal oxide layer on the surface of the doped modified titanium dioxide. It not only has excellent electrical conductivity and weather resistance, but also has the advantages of small particle size and easy dispersion, and has good formula applicability, and can be used in conductive coatings.

[0016] 2. The existence of the organic layer in the conductive titanium white powder improves the electrical conductivity of the doped modified titanium dioxide, and forms a dense and firm coating layer on the surface of the doped modified titanium dioxide, preventing agglomeration and reducing particle size, reducing the photoactivity of the doped modified titanium dioxide, and improving the electrical conductivity, dispersibility and weather resistance of the doped modified titanium dioxide. Further, the existence of the organic layer provides growth sites for the coating of the metal oxide layer, improving the coating effect of the metal oxide layer.

[0017] 3. The outermost layer of the conductive titanium white powder is a zinc oxide doped tin oxide metal oxide layer. Under the joint action of tin oxide and zinc oxide, the electrical conductivity and weather resistance of the titanium white powder are further improved.

[0018] 4. In the process of preparing the doped modified titanium dioxide, glycolic acid is used as an auxiliary agent to promote the formation of rutile titanium dioxide. Rutile titanium dioxide has better stability and weather resistance than anatase titanium dioxide, and the doping of metallic tantalum in titanium dioxide can effectively improve the electrical conductivity of rutile titanium dioxide. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a comparison chart of volume resistivity tests of the conductive titanium white powder prepared in Examples 2-6 and Comparative Examples 1-5 of the present application; Figure 2is a comparison chart of methylene blue degradation rate tests of the conductive titanium white powder prepared in the embodiments 2-6 of the present application and the comparative examples 1-5. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0021] Embodiment 1 The present embodiment discloses a preparation method of an organic monomer, comprising the following steps: Step S1, 3.5g acetoacetyl methyl methacrylate is added into 90g ethanol, stirred for 15min, then 1.9g 3-mercapto-2-methyl-pentanal, 0.04g azobisisobutyronitrile are added, heated to 65℃, stirred for 4h, after the reaction is completed, the solvent and unreacted acetoacetyl methyl methacrylate are removed by rotary evaporation, to obtain an intermediate product A; 3g intermediate product A, 1.9g 1-amino-3-buten-2-ol are added into 90g ethanol, stirred until uniform, heated to 70℃, stirred for 3h, after the reaction is completed, the solvent and unreacted 1-amino-3-buten-2-ol are removed by rotary evaporation, to obtain an intermediate product B; Step S2, 3g 2,5-dicarboxylic acid-3,4-ethylenedioxythiophene is mixed with 8.9g thionyl chloride, stirred for 3.5h, then reacted at 80℃ for 25min, the excess thionyl chloride is removed by distillation, to obtain a thiophene-based compound; 3.4g thiophene-based compound is added into 25g ethanol, stirred for 30min, to obtain a thiophene-based compound dispersion; 5.2g intermediate product B is added into 70g ethanol, in an ice water bath, the above-mentioned thiophene-based compound dispersion is added dropwise at a rate of 1.5mL / min while stirring, first reacted at 0℃ for 2h, then reacted at 25℃ for 4h, after the reaction is completed, the solvent is evaporated, to obtain an organic monomer.

[0022] Embodiment 2

[0023] The present embodiment discloses a preparation method of a conductive titanium white powder, comprising the following steps: Step one, ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution are mixed in a volume ratio of 0.22:5:5:50, first stirred at 78℃ at a speed of 500r / min for 2.5h, then hydrothermally reacted at a temperature of 195℃ and a pressure of 1.6MPa for 7h, after the reaction is completed, cooled to room temperature, centrifuged, washed, and dried, to obtain doped modified titanium dioxide; Step two, 5g of doped modified titanium dioxide is added into 200g of dimethylformamide, ultrasonic treatment for 20min, then 6.6g of organic monomer is added, stirring at 23℃ for 60min under nitrogen atmosphere, then heated to 75℃, 0.1g of ammonium persulfate is added, stirring for 7h, after the reaction, centrifugal, washing, drying, to get organic modified titanium dioxide; Step three, 1.4g of tin chloride pentahydrate is added into 24g of ethanol to prepare solution A; 0.55g of zinc chloride, 0.84g of citric acid is added into 100g of water to prepare solution B; solution A is added into solution B, stirring for 10min, then 12g of organic modified titanium dioxide is added, then 55g of 4mol / L sodium hydroxide aqueous solution is added, ultrasonic treatment for 1h, filtration, washing, drying, the dried product is calcined at 590℃ for 150min under argon atmosphere, to get conductive titanium white powder.

[0024] Example 3

[0025] The embodiment discloses a preparation method of conductive titanium white powder, comprising the following steps: Step one, ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution are mixed in a volume ratio of 0.3:5:5:50, stirring at 82℃ and a rotating speed of 500r / min for 2.5h, then hydrothermal reaction is carried out at a temperature of 205℃ and a pressure of 1.6MPa for 5h, after the reaction, cooling to room temperature, centrifugal, washing, drying, to get doped modified titanium dioxide; Step two, 9g of doped modified titanium dioxide is added into 300g of dimethylformamide, ultrasonic treatment for 40min, then 17.2g of organic monomer is added, stirring at 28℃ for 40min under nitrogen atmosphere, then heated to 85℃, 0.2g of ammonium persulfate is added, stirring for 5h, after the reaction, centrifugal, washing, drying, to get organic modified titanium dioxide; Step three, 2.8g of tin chloride pentahydrate is added into 24g of ethanol to prepare solution A; 1.1g of zinc chloride, 1.68g of citric acid is added into 100g of water to prepare solution B; solution A is added into solution B, stirring for 20min, then 20g of organic modified titanium dioxide is added, then 110g of 4mol / L sodium hydroxide aqueous solution is added, ultrasonic treatment for 2h, filtration, washing, drying, the dried product is calcined at 610℃ for 100min under argon atmosphere, to get conductive titanium white powder.

[0026] Example 4 The embodiment discloses a preparation method of conductive titanium white powder, comprising the following steps: Step one, the tantalum ethoxide, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution is mixed with a volume ratio of 0.26:5:5:50, first stirred at 80℃ with a speed of 500r / min for 2h, then hydrothermal reaction is carried out at a temperature of 200℃ and a pressure of 1.6MPa for 6h, after the reaction, the product is cooled to room temperature, centrifuged, washed and dried to obtain the doped modified titanium dioxide; Step two, 7g of the doped modified titanium dioxide is added into 250g of dimethylformamide, ultrasonic treatment is carried out for 30min, then 11.9g of the organic monomer is added, stirring is carried out at 25℃ for 50min in a nitrogen atmosphere, then the temperature is increased to 80℃, 0.15g of ammonium persulfate is added, and stirring reaction is carried out for 6h, after the reaction, the product is centrifuged, washed and dried to obtain the organic modified titanium dioxide; Step three, 2.1g of tin chloride pentahydrate is added into 24g of ethanol to prepare solution A; 0.83g of zinc chloride and 1.26g of citric acid are added into 100g of water to prepare solution B; solution A is added into solution B, stirring is carried out for 15min, then 16g of the organic modified titanium dioxide is added, 82.5g of 4mol / L sodium hydroxide aqueous solution is added, ultrasonic treatment is carried out for 1.5h, the product is filtered, washed and dried, and the dried product is calcined at 600℃ for 125min in an argon atmosphere to obtain the conductive titanium white powder.

[0027] Example 5 The embodiment discloses a preparation method of a conductive titanium white powder, comprising the following steps: Step one, the tantalum ethoxide, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution is mixed with a volume ratio of 0.24:5:5:50, first stirred at 79℃ with a speed of 500r / min for 1.8h, then hydrothermal reaction is carried out at a temperature of 198℃ and a pressure of 1.6MPa for 5.5h, after the reaction, the product is cooled to room temperature, centrifuged, washed and dried to obtain the doped modified titanium dioxide; Step two, 6g of the doped modified titanium dioxide is added into 225g of dimethylformamide, ultrasonic treatment is carried out for 25min, then 9.3g of the organic monomer is added, stirring is carried out at 24℃ for 55min in a nitrogen atmosphere, then the temperature is increased to 78℃, 0.13g of ammonium persulfate is added, and stirring reaction is carried out for 5.5h, after the reaction, the product is centrifuged, washed and dried to obtain the organic modified titanium dioxide; Step three, 2.5g tin chloride pentahydrate was added into 24g ethanol to prepare solution A; 0.97g zinc chloride, 1.47g citric acid were added into 100g water to prepare solution B; solution A was added into solution B, stirred for 15min, then 18g organic modified titanium dioxide was added, followed by 96.3g 4mol / L sodium hydroxide aqueous solution, ultrasonic treatment for 1.8h, filtration, washing, drying, the dried product was calcined in argon atmosphere at 605℃ for 115min to obtain conductive titanium dioxide.

[0028] Example 6 The present example discloses a method for preparing conductive titanium dioxide, comprising the following steps: Step one, ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution were mixed at a volume ratio of 0.28:5:5:50, first stirred at 81℃ at a speed of 500r / min for 2.3h, then hydrothermal reaction was carried out at a temperature of 203℃ and a pressure of 1.6MPa for 6.5h, after the reaction, the mixture was cooled to room temperature, centrifuged, washed and dried to obtain doped modified titanium dioxide; Step two, 8g doped modified titanium dioxide was added into 275g dimethylformamide, ultrasonic treatment for 35min, then 14.6g organic monomer was added, stirring at 27℃ for 55min, then the temperature was increased to 83℃, 0.18g ammonium persulfate was added, and the mixture was stirred for 6.5h, after the reaction, the mixture was centrifuged, washed and dried to obtain organic modified titanium dioxide; Step three, 2.5g tin chloride pentahydrate was added into 24g ethanol to prepare solution A; 0.97g zinc chloride, 1.47g citric acid were added into 100g water to prepare solution B; solution A was added into solution B, stirred for 15min, then 18g organic modified titanium dioxide was added, followed by 96.3g 4mol / L sodium hydroxide aqueous solution, ultrasonic treatment for 1.8h, filtration, washing, drying, the dried product was calcined in argon atmosphere at 605℃ for 115min to obtain conductive titanium dioxide.

[0029] The organic monomer used in the above examples 2-6 is the organic monomer prepared in example 1.

[0030] Comparative example 1 The present example discloses a method for preparing conductive titanium dioxide, comprising the following steps: Step one, ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution were mixed at a volume ratio of 0.26:5:5:50, first stirred at 80℃ at a speed of 500r / min for 2h, then hydrothermal reaction was carried out at a temperature of 200℃ and a pressure of 1.6MPa for 6h, after the reaction, the mixture was cooled to room temperature, centrifuged, washed and dried to obtain doped modified titanium dioxide; Step two, 7g of doped modified titanium dioxide was added into 250g of dimethylformamide, ultrasonic treatment for 30min, then 11.9g of intermediate product B prepared in example 1 was added, stirring at 25℃ for 50min under nitrogen atmosphere, then heated to 80℃, 0.15g of ammonium persulfate was added, stirring for 6h, after the reaction, centrifugation, washing, drying, to obtain organically modified titanium dioxide; Step three, 2.1g of tin chloride pentahydrate was added into 24g of ethanol to prepare solution A; 0.83g of zinc chloride and 1.26g of citric acid were added into 100g of water to prepare solution B; solution A was added into solution B, stirring for 15min, then 16g of organically modified titanium dioxide was added, 82.5g of 4mol / L sodium hydroxide aqueous solution was added, ultrasonic treatment for 1.5h, filtration, washing, drying, the dried product was calcined at 600℃ for 125min under argon atmosphere, to obtain conductive titanium white powder.

[0031] Comparative example 2 The present comparative example discloses a preparation method of conductive titanium white powder, comprising the following steps: Step one, ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution were mixed in a volume ratio of 0.26:5:5:50, first stirring at 80℃ for 2h at a speed of 500r / min, then hydrothermal reaction at a temperature of 200℃ and a pressure of 1.6MPa for 6h, after the reaction, cooling to room temperature, centrifugation, washing, drying, to obtain doped modified titanium dioxide; Step two, 2.1g of tin chloride pentahydrate was added into 24g of ethanol to prepare solution A; 0.83g of zinc chloride and 1.26g of citric acid were added into 100g of water to prepare solution B; solution A was added into solution B, stirring for 15min, then 16g of organically modified titanium dioxide was added, 82.5g of 4mol / L sodium hydroxide aqueous solution was added, ultrasonic treatment for 1.5h, filtration, washing, drying, the dried product was calcined at 600℃ for 125min under argon atmosphere, to obtain conductive titanium white powder.

[0032] Comparative example 3 The present comparative example discloses a preparation method of conductive titanium white powder, comprising the following steps: Step one, titanium tetraisopropoxide, isopropyl alcohol, 1.6mol / L glycolic acid aqueous solution were mixed in a volume ratio of 5:5:50, first stirring at 80℃ for 2h at a speed of 500r / min, then hydrothermal reaction at a temperature of 200℃ and a pressure of 1.6MPa for 6h, after the reaction, cooling to room temperature, centrifugation, washing, drying, to obtain nano titanium dioxide; Step two, 7g nano-titanium dioxide was added into 250g dimethylformamide, and ultrasonic treatment was performed for 30min, 11.9g organic monomer prepared in Example 1 was added, stirring was performed at 25℃ for 50min under nitrogen atmosphere, then temperature was increased to 80℃, 0.15g ammonium persulfate was added, stirring reaction was performed for 6h, after reaction was completed, centrifugal separation was performed, washing was performed, and drying was performed, to obtain organically modified titanium dioxide; Step three, 2.1g tin chloride pentahydrate was added into 24g ethanol to prepare solution A; 0.83g zinc chloride and 1.26g citric acid were added into 100g water to prepare solution B; solution A was added into solution B, stirring was performed for 15min, then 16g organically modified titanium dioxide was added, 82.5g 4mol / L sodium hydroxide aqueous solution was added, ultrasonic treatment was performed for 1.5h, filtration was performed, washing was performed, and drying was performed, the dried product was calcined at 600℃ for 125min under argon atmosphere, to obtain conductive titanium white powder.

[0033] Comparative Example 4 The present comparative example discloses a preparation method of conductive titanium white powder, comprising the following steps: Step one, ethanol tantalum, titanium tetraisopropoxide, isopropyl alcohol, and 1.6mol / L glycolic acid aqueous solution were mixed in a volume ratio of 0.26:5:5:50, stirring was performed at 80℃ and a rotating speed of 500r / min for 2h, then hydrothermal reaction was performed at a temperature of 200℃ and a pressure of 1.6MPa for 6h, after reaction was completed, cooling was performed to room temperature, centrifugal separation was performed, washing was performed, and drying was performed, to obtain doped modified titanium dioxide; Step two, 7g doped modified titanium dioxide was added into 250g dimethylformamide, and ultrasonic treatment was performed for 30min, 11.9g organic monomer prepared in Example 1 was added, stirring was performed at 25℃ for 50min under nitrogen atmosphere, then temperature was increased to 80℃, 0.15g ammonium persulfate was added, stirring reaction was performed for 6h, after reaction was completed, centrifugal separation was performed, washing was performed, and drying was performed, to obtain organically modified titanium dioxide; Step three, 2.1g tin chloride pentahydrate was added into 24g ethanol to prepare solution A; 0.83g zinc chloride and 1.26g citric acid were added into 100g water to prepare solution B; solution A was added into solution B, stirring was performed for 15min, then 16g organically modified titanium dioxide was added, 82.5g 4mol / L sodium hydroxide aqueous solution was added, ultrasonic treatment was performed for 1.5h, filtration was performed, washing was performed, and drying was performed, the dried product was calcined at 600℃ for 125min under argon atmosphere, to obtain conductive titanium white powder.

[0034] Comparative Example 4 The present comparative example discloses a preparation method of conductive titanium white powder, comprising the following steps: Step one, mixing the tantalum ethoxide, titanium tetraisopropoxide, isopropyl alcohol, 1.6 mol / L glycolic acid aqueous solution with the volume ratio of 0.26:5:5:50, stirring at 500 r / min for 2 h at 80℃, then hydrothermal reaction at 200℃ and 1.6 MPa for 6 h, cooling to room temperature, centrifuging, washing, and drying to obtain the doped modified titanium dioxide; Step two, adding 7 g of the doped modified titanium dioxide into 250 g of dimethylformamide, ultrasonic treatment for 30 min, then adding 11.9 g of the organic monomer prepared in Example 1, stirring at 25℃ for 50 min under nitrogen atmosphere, then increasing the temperature to 80℃, adding 0.15 g of ammonium persulfate, stirring for 6 h, then centrifuging, washing, and drying to obtain the conductive titanium white powder.

[0035] Experimental example I. Conductivity test: weighing 2.0 g of the conductive titanium white powder samples prepared in Examples 2-6 and Comparative Examples 1-5, pressing the samples into powder sheets with a diameter of 0.4 cm and a thickness of 0.2 cm under a pressure of 20 MPa, measuring the resistance of each group of powder sheets, and calculating the volume resistivity according to the following formula: ; In the formula, R is the resistance of the powder sheet (Ω), S is the cross-sectional area of the powder sheet (cm2), and L is the height of the powder sheet (cm).

[0036] II. Weather resistance test: weighing 100 mg of the conductive titanium white powder samples prepared in Examples 2-6 and Comparative Examples 1-5, respectively, adding into 100 mL of 10 g / L methylene blue solution, irradiating and stirring in a dark room with an ultraviolet lamp (395 nm). Taking samples every 1 h, and measuring the absorbance of methylene blue at 664 nm with an ultraviolet-visible spectrophotometer. Calculating the degradation rate of methylene blue after 5 h using (1-A t / A0) (wherein At is the concentration of the methylene blue solution after a certain period of reaction, and A0 is the initial concentration of the methylene blue solution). The higher the degradation rate of methylene blue, the stronger the photocatalytic activity of the titanium white powder, and the worse the weather resistance; on the contrary, the better the weather resistance of the titanium white powder.

[0037] The test results are shown in Table 1: Table 1 Volume resistivity / (Ω-cm) Degradation rate of methylene blue / % Example 2 17.6 3.53 Example 3 11.2 2.28 Example 4 14.9 2.91 Example 5 16.3 3.29 Example 6 12.7 2.65 Comparative Example 1 19.1 2.90 Comparative Example 2 27.5 3.83 Comparative Example 3 19.6 2.91 Comparative Example 4 22.2 3.66 Comparative Example 5 26.3 4.01 From the test results of Table 1, it can be seen that the conductive titanium dioxide powder prepared in Examples 2-6 has excellent conductivity and weather resistance. From the comparison between Comparative Example 1 and Example 4, it can be seen that the presence of the thiophene moiety in the organic layer of the conductive titanium dioxide powder has a significant influence on the conductivity of the titanium dioxide powder. From the comparison between Comparative Example 2 and Example 4, it can be seen that the presence of the organic layer in the conductive titanium dioxide powder of the present application improves the conductivity of the doped modified titanium dioxide on the one hand, and on the other hand, forms a dense and firm coating layer on the surface of the doped modified titanium dioxide, prevents its agglomeration, thereby reducing the particle size, reduces the photoactivity of the doped modified titanium dioxide, and further, the presence of the organic layer provides growth sites for the coating of the metal oxide layer, improves the coating effect of the metal oxide layer, and thereby improves the conductivity and weather resistance of the doped modified titanium dioxide. From the comparison between Comparative Example 3 and Example 4, it can be seen that the doping of metal tantalum in the titanium dioxide can effectively improve its conductivity. From the comparison between Comparative Examples 4-5 and Example 4, it can be seen that under the joint action of tin oxide and zinc oxide, the conductivity and weather resistance of the titanium dioxide powder are further improved.

[0038] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for producing an electrically conductive titanium white pigment, characterized by, The method comprises the following steps: Step one, using tantalum ethoxide, titanium tetraisopropoxide, isopropyl alcohol, aqueous glycolic acid as raw materials, reacting to prepare doped modified titanium dioxide; Step two, coating the doped modified titanium dioxide with organic monomers to obtain organically modified titanium dioxide; Step three, coating the organically modified titanium dioxide with metal oxides to obtain conductive titanium white powder.

2. The method for preparing conductive titanium dioxide according to claim 1, characterized in that, In step one, the volume ratio of the tantalum ethoxide, titanium tetraisopropoxide, isopropyl alcohol, and aqueous glycolic acid is (0.22-0.3):5:5:50; the average particle size of the doped modified titanium dioxide is 170 nm.

3. The method for preparing conductive titanium dioxide according to claim 1, characterized in that, In step one, the reaction conditions are as follows: first stirring at a speed of 500 r / min at 78-82℃ for 1.5-2.5h, and then hydrothermal reaction at a temperature of 195-205℃ and a pressure of 1.6MPa for 5-7h.

4. The method for preparing conductive titanium dioxide according to claim 1, characterized in that, In step two, the preparation method of the organically modified titanium dioxide specifically comprises: adding the doped modified titanium dioxide into dimethylformamide, ultrasonic, then adding organic monomers, stirring at 23-28℃ for 40-60min, then increasing the temperature to 75-85℃, adding ammonium persulfate, stirring and reacting for 5-7h, and then purifying to obtain the organically modified titanium dioxide; wherein the mass ratio of the doped modified titanium dioxide, dimethylformamide, organic monomers, and ammonium persulfate is (5-9):(200-300):(6.6-17.2):(0.1-0.2).

5. The method for preparing conductive titanium dioxide according to claim 1, characterized in that, The organic monomers in step two are prepared by the following steps: Step S1, mixing the intermediate product A, 1-amino-3-buten-2-ol, and ethanol with a mass ratio of (2.4-3.6):(1.3-2.5):(80-100), stirring, heating to 66-74℃, stirring and reacting for 2-4h, and then purifying to obtain the intermediate product B; Step S2, mixing the thiophene-based compound and ethanol with a mass ratio of (2.7-4):(20-30), stirring to obtain a thiophene-based compound dispersion liquid; mixing the intermediate product B and ethanol with a mass ratio of (4.2-6.2):(60-80), adding the thiophene-based compound dispersion liquid dropwise in an ice water bath, first reacting at 0℃ for 2h, then reacting at 23-28℃ for 3.5-4.5h, and then purifying to obtain the organic monomers.

6. The method for preparing conductive titanium dioxide according to claim 5, characterized in that, The intermediate product A in step S1 is prepared by the following steps: adding acetoacetoxy ethyl methacrylate into ethanol, stirring, then adding 3-mercapto-2-methyl-pentanal and azobisisobutyronitrile, heating to 60-70℃, stirring and reacting for 3-5h, and then purifying to obtain the intermediate product A; wherein the mass ratio of acetoacetoxy ethyl methacrylate, ethanol, 3-mercapto-2-methyl-pentanal, and azobisisobutyronitrile is (2.5-4.5):(80-100):(1.3-2.6):(0.03-0.05).

7. The method for preparing conductive titanium dioxide according to claim 5, characterized in that, The thiophene-based compound in step S2 is prepared by the following steps: Mixing 2,5-dicarboxylic acid-3,4-vinylenedithiophene and thionyl chloride in a mass ratio of (2.3-3.5):(5.9-11.8), stirring for 3-4 hours, then reacting at 76-84℃ for 20-30 minutes, purifying to obtain a thienyl compound.

8. The method for preparing conductive titanium dioxide according to claim 1, characterized in that, In the step three, the preparation method of the conductive titanium white powder specifically comprises: SnCl2.5H2O is added into ethanol to prepare solution A; ZnCl2 and citric acid are added into water to prepare solution B; solution A is added into solution B, stirring, then adding organic modified titanium dioxide, adding 4 mol / L NaOH aqueous solution, ultrasonic treatment for 1-2 hours, filtering, washing, drying, calcining the dried product in argon atmosphere at 590-610℃ for 100-150 minutes to obtain the conductive titanium white powder; wherein the mass ratio of SnCl2.5H2O, ZnCl2, citric acid, organic modified titanium dioxide and 4 mol / L NaOH aqueous solution is (1.4-2.8):(0.55-1.1):(0.84-1.68):(12-20):(55-110).

9. The conductive titanium white powder prepared by the preparation method of the conductive titanium white powder according to any one of claims 1-8.

10. The conductive titanium white powder according to claim 9 in the application of conductive coating.

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