Carboxylation modified nano titanium dioxide ultraviolet screening agent and preparation method thereof

[0038] The carboxylated modified nano TiO of the present invention 2 The preparation method of the ultraviolet shield, including the steps of: 8 to 10 copies of TiO according to the mass fraction 2 -NH 2 Add to 100 to 120 parts of anhydrous ethanol, ultrasonic dispersion of 30 min, pour the suspension into the three flasks, stir the stirred and warmed to 60 ° C, the rotation speed is 400 r / min, add 4 ~ 8 aldehyde substances and 3 to 5 parts. Acrylic acid, 60 ° C magnetic stirring reaction for 5 h, cooled, centrifugally, remove the upper cleaner, after washing the resulting lower white precipitol, 0.0 ° C under vacuum ovens for 5 hours to obtain carboxylated modified nano TiO 2 Ultraviolet shield. Among them, TIO 2 -NH 2 Is γ-aminopropyltriethoxysilane with nano TiO 2 Reaction, in nano TiO 2 The surface is introduced into an amino group.

[0039] Specifically, the carboxylated modified nano TiO of the present invention 2 The preparation method of the ultraviolet shield, including the following steps:

[0040] Step 1: TIO 2 -NH 2 Preparation

[0041] According to the number of parts, 7 ~ 12 nano TiO will 2 Dry from 40 to 80 ° C for 2 to 6 hours; 1 to 4 γ-aminopropyltriethoxysilanes were added to a beaker equipped with 20 to 80 parts of anhydrous ethanol and ultrapoprosis, magnetic stirring , Pre-hydrolysis 30 ~ 60min; will dry the nano TiO 2 Add the ultrasound dispersed from 1 to 2 h in a beaker with 70 ~ 120 parts of anhydrous ethanol and ultrapocyst mixed solution, nano TiO 2 The dispersion was poured into a three flask, stirring the water bath, and the water bath temperature of the reaction system was 30 to 45 ° C, and the neutralizing agent was adjusted to neutral, stirred at 30 to 60 min; reacting the reaction system The water bath temperature rose to 60 ~ 80 ° C, slowly dropped the gamma-aminopropyltriethoxysilane prehydly to the three flasks, after the dropping, the insulation reaction was 4 ~ 6 h; the reaction was centrifuged after the reaction was completed. , Take solid wash, put it in an oven at 50 ~ 80 ° C for 4 to 8 h, to obtain TiO 2 -NH 2.

[0042] Step 2: Carboxylated modified nano TiO 2 Preparation of ultraviolet mask

[0043] According to the mass fraction, 8 ~ 10 copies of TIO 2 -NH 2 Add to 100 to 120 parts of anhydrous ethanol, ultrasonic dispersion of 30 min, pour the suspension into the three flasks, stir the stirred and warmed to 60 ° C, the rotation speed is 400 r / min, add 4 ~ 8 aldehyde substances and 3 to 5 parts. Acrylic acid, 60 ° C magnetic stirring reaction reaction for 5 h, cooled, centrifuged, alcohol, dried in a vacuum oven at 40 ° C for 5 h to obtain carboxylated nano TiO 2 Ultraviolet shield.

[0044] Step one medium nanometer TiO 2 And the mass ratio of γ-aminopropyltriethoxysilane is (7 to 12): (1 to 4); γ-aminopropyltriethoxysilane prehydrolysis quality of water mixed solution The ratio is (0.5 ~ 1.2): (5 ~ 12); γ-aminopropyltriethoxysilane's pre-hydraulic solution is 30 to 60 min; the neutralizing agent is one of sodium hydroxide, ammonia water; stirring speed 200 ~ 400R / min; product centrifugation speed is 2000 ~ 3000R / min;

[0045] The second Mid Manni reaction is polymerized with solution, and the solvent used is anhydrous ethanol; the aldehyde substance is one of formaldehyde, methaldehyde and glutaraldehyde; TIO 2 -NH 2 , The mass ratio of aldehyde substance and acrylic acid is (8 ~ 10): (4 to 8): (3 to 5); reaction stirring speed is 300 to 450 r / min.

[0046] The present invention will be described in detail below in conjunction with specific embodiments. These examples are only the features and advantages of the present invention, not the claims of the invention.

[0047] A man-based modified nano-TiO based on Manni reaction according to the present invention 2 UV shield and preparation method thereof, TIO 2 -NH 2 For the raw material, the aldehyde substance is a crosslinking agent, acrylic acid is a modifier, and ultraviolet shielding agents for the preparation of dispersibility, reaction activity, and ultraviolet shielding performance by Manni Reaction.

[0048] Example 1:

[0049] Step 1: TIO 2 -NH 2 Preparation

[0050] 1G nanometer TiO 2 Put it in an oven at 60 ° C for 4 h to give a dry nanometer TiO 2 0.5 g of the aminoopropyltriethoxysilane is added to a beaker equipped with 150 g of anhydrous ethanol and ultrapoprophy water mixing solution (absolute ethanol and ultrapure water), magnetic stirring, pre- Hydrolysis 50min, gave gamma-aminopropyltriethoxysilane prehydrolyzed; the dry nano TiO 2 Add 80 g of anhydrous ethanol and ultrapure water mixed solution (absolute ethanol and ultrapure water mass ratio of 4: 1), ultrasonic dispersion for 1 h, to obtain nano TiO 2 Dispersion, will nano TiO 2 The dispersion was poured into a three flask, stirring the water bath, and the water bath temperature of the reaction system was 40 ° C, the stirring speed was 300 r / min, and the ammonia water was adjusted to neutral, stirred for 40 min, resulting in neutrality Nano Tio 2 Dispersion; raised the water bath temperature of the reaction system to 65 ° C, slowly drop the γ-aminopropyltriethoxysilane prehydrolysis to the neutral nano TiO of three flasks 2 In the dispersion, after the dropwise addition, the insulation reaction was 5 h; after the reaction was completed, the product was centrifuged, washed, and then dried in an oven at 60 ° C for 6 h, resulting in TiO2 -NH 2.

[0051] Step two: carboxylated modified nano TiO 2 Preparation

[0052] The 1g TiO 2 -NH 2 Was added to 100g of anhydrous ethanol, ultrasonic dispersion 30min, to obtain a reaction system (suspension), the suspension was poured into a three-necked flask, the water bath set temperature of the reaction system was 45 ℃, stirring the reaction speed of 400r / min, was added 0.4g glyoxal and 0.3g of acrylic acid, 5h the reaction, the product was cooled, centrifuged, washed alcohols, carboxyl modification of TiO to give after vacuum drying oven at 40 ℃ 5h 2 Ultraviolet shield.

[0053] Example 2:

[0054] Step a: TiO 2 -NH 2 Preparation

[0055] Weigh 1g of TiO 2 Placed in an oven dried 4h at 60 ℃, to give after drying of TiO 2; The 0.5gγ- aminopropyl triethoxysilane was added with 150g of anhydrous ethanol, and ultrapure water mixed solution (ethanol, and ultrapure water in a mass ratio of 9: 1) in a beaker, with magnetic stirring, a pre- hydrolysis 50min, to give γ- aminopropyl triethoxysilane pre-hydrolyzate; after the drying of TiO 2 80g of anhydrous ethanol was added with ultrapure water and a mixed solution (ethanol, and ultrapure water in a mass ratio of 4: 1) in an ultrasonic dispersion beaker 1h, to give Nanocrystalline TiO 2 Dispersion, nano-TiO 2 Dispersion was poured into a three-necked flask, heated water bath with stirring, the water bath set temperature of the reaction system was 40 ℃, stirring speed of 300r / min, and the sodium hydroxide the pH of the reaction system was adjusted to neutral, the reaction was stirred for 40min, to give neutral Nanocrystalline TiO 2 Dispersion; bath temperature the reaction system was increased to 65 ℃, the γ- aminopropyl triethoxysilane prehydrolysis was slowly added dropwise into a three-necked flask neutral Nanocrystalline TiO 2 Dispersion, after the addition was complete, the reaction was kept 5H; The product was centrifuged and washed after the completion of the reaction, placed in an oven dried for 6h at 60 ℃, to obtain TiO 2 -NH 2.

[0056] Step two: carboxylated modified nano TiO 2 Preparation

[0057] The 1.2g TiO 2 -NH 2 Was added to 100g of anhydrous ethanol, ultrasonic dispersion 30min, to obtain a reaction system (suspension), the suspension was poured into a three-necked flask, the water bath set temperature of the reaction system was 45 ℃, stirring the reaction speed of 400r / min, was added 0.65g glutaraldehyde and 0.5g of acrylic acid, 5h the reaction, the product was cooled, centrifuged, washed alcohol, to give after carboxy modification of TiO 5h 40 ℃ dried in a vacuum oven 2 Ultraviolet shield.