CN108165054B - Preparation method of cationic carbon black - Google Patents

Abstract

The invention relates to a preparation method of cationic carbon black. The method comprises the steps of taking nano carbon black as a raw material, tetraethoxysilane as a precursor, strong ammonia water as a catalyst, ethanol aqueous solution as a solvent, epichlorohydrin and tertiary amine as modifiers, carrying out quaternization reaction under certain conditions, carrying out centrifugal washing, dispersing in aqueous solution to obtain a cationic carbon black dispersion, and drying to obtain cationic carbon black powder. The cationic carbon black is prepared by covalently grafting the cationic quaternary ammonium functional group on the surface of the carbon black, has small granularity and good dispersibility due to positive charges on the surface, and can be used in the production fields of fabric and hair coloring, ink-jet coating, rubber plastic filling and the like.

Description

A kind of preparation method of cationic carbon black

technical field

The invention relates to a preparation method of nanometer carbon black with covalently grafted cationic groups on the surface.

Background technique

Black dyes and pigments are widely used in textiles, cosmetics, coatings and other fields. At present, the black dyes widely used in the field of printing and dyeing are mostly azo dyes, which have good chemical stability and good color fastness, but reductive cracking will produce carcinogens that endanger human health.

Carbon black is a kind of amorphous carbon, light, loose and extremely fine black powder with particle size ranging from tens of nanometers to hundreds of nanometers. It has excellent reinforcement, coloring, light resistance, etc. It is widely used. Used in inks, paints, plastics and coatings and other fields. At the same time, carbon black has a natural black color, which can replace azo dyes as an ideal black pigment. At present, carbon black particles with a sufficiently small particle size are mostly used, and dispersant treatment or surface oxidation modification is used to prepare dispersed carbon black pigments. These modified carbon black dispersions have good dispersibility, and rely on intermolecular forces to achieve coloration. However, the special functional groups on the surface of carbon black itself are less, and the intermolecular force is weak, which limits its coloring performance to a certain extent.

Quaternary ammonium salts, also known as quaternary ammonium salts, are compounds in which four hydrogen atoms in ammonium ions are replaced by hydrocarbon groups, and the central nitrogen atom has a positive charge. In the textile printing and dyeing industry, it can be used as softener and antistatic agent, with excellent softening, antistatic, bactericidal and anti-yellowing properties, less dosage, good effect, convenient preparation, good compatibility, and high cost performance; In the water treatment industry, it is used as a flocculant, a demulsifier, and as a quaternary ammonium salt for an inorganic flocculant synergist; in the petroleum industry, it can be used as a drilling fluid, VES fracturing fluid, drag reducer, and thickener; As well as antibacterial agents, anionic synergists, etc.

Combined with the excellent properties of cationic quaternary ammonium salts, the present invention covalently grafts cationic quaternary ammonium functional groups on the surface of carbon black. The cationic groups can improve the chemical activity and water solubility of carbon black, and can be adsorbed on the surface of negatively charged substances through electrostatic action. , such as acrylic fibers, blended fabrics, etc. The hydrophobic long-chain aliphatic hydrocarbon in the quaternary ammonium component can increase the surface steric hindrance of carbon black, reduce the self-agglomeration of carbon black, and improve the performance of carbon black. In addition, covalent grafting of weak cationic amino acids on the surface of carbon black can improve the biocompatibility of carbon black, and can be used as a colorant for daily cosmetics.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a preparation method of cationic carbon black in order to improve the deficiencies of the prior art, and the surface performance of the carbon black is improved by covalently grafting quaternary ammonium functional groups on the surface of the carbon black.

The technical scheme adopted in the present invention is: a preparation method of cationic nanometer carbon black, and its concrete steps are as follows:

A) Mix and stir a certain amount of nano-carbon black, catalyst and solvent evenly, add tetraethyl orthosilicate ethanol solution dropwise at the temperature, and react for a certain period of time;

B) In the mixed solution of A), add epichlorohydrin, keep the temperature reaction, then add tertiary amine or amino acid and derivatives thereof, and carry out quaternization reaction under temperature control;

C) Take the cationic carbon black mixture prepared in step B) and wash it by centrifugation until the pH is neutral, and then disperse in water to obtain a modified cationic carbon black dispersion, which is dried to obtain cationic carbon black.

Preferably, the particle size of the nano-carbon black in step A) is 15-50 nm. Preferably, in step A), the solvent is an aqueous ethanol solution with a volume concentration of 80 to 100%.

Preferably, the volume ratio of tetraethyl orthosilicate and ethanol in the tetraethyl orthosilicate ethanol solution described in step A) is 1: (2.5~5).

Preferably, the catalyst described in step A) is concentrated ammonia water, and the mass concentration of the concentration is 25-28%; the mass-volume ratio of the nano-carbon black powder and the catalyst is 1: (1-4) g/mL.

Preferably, the mass-volume ratio of the nano-carbon black powder and tetraethyl orthosilicate described in step A) is 1: (2~4) g/mL.

Preferably, in step A), the temperature at which the temperature of the tetraethyl orthosilicate ethanol solution is added dropwise is 40 ^oC ~ 60 ^oC ; the reaction time is 1 ~ 3h.

Preferably, the tertiary amine described in step B) is the one in dodecyl tertiary amine, dodecyl tetradecyl tertiary amine, hexadecyl tertiary amine or 3-dimethylaminopropylamine; the mol ratio of tertiary amine and epichlorohydrin is 1: (1~1.1).

Preferably, the amino acid and its derivative described in step B) are a kind of arginine, arginine hydrochloride or arginine ethyl ester hydrochloride, and the mol ratio of amino acid and its derivative to epichlorohydrin is 1: (1~1.1).

Preferably, in step B), the temperature for maintaining the temperature reaction is 40 ^oC to 60 ^oC , and the reaction time is 1 to 3h; the quaternization reaction temperature is 50 to 70 ^oC ; and the reaction time is 1 to 3h.

Preferably, the molar ratio of tetraethyl orthosilicate in step A) and epichlorohydrin in step B) is 1:(0.5~3).

Beneficial effects:

1. The average particle size of the cationic carbon black particles prepared by the present invention is small (30-70nm), and the surface is covalently grafted with cationic functional groups, which can have certain characteristics and good dispersibility of quaternary ammonium salts, and the zeta potential shows that the surface has a positive charge .

2. Cationic carbon black can be used as pigment carbon black for fabric coloring, which can save the pretreatment of fabric, and its coloring performance is better than that of pure carbon black.

3. Amino acid-modified cationic carbon black improves the biocompatibility of carbon black and can be used as a black colorant for daily cosmetics.

4. The coloring process of cationic carbon black pigment is safe and will not produce harmful substances like organic dyes.

Description of drawings

Fig. 1 is the infrared spectrum of the CB@SiO2 core-shell structure composite material, epichlorohydrin covalently modified CB@SiO2 composite material, and cationic carbon black prepared in Example 1.

2 is a TEM image of the cationic carbon black prepared in Example 18.

3 is a thermogravimetric analysis diagram of the cationic carbon black prepared in Example 1, Example 17, Example 18, and Example 19.

Figure 4 is a comparison chart of Example 18 and pure carbon black on the coloration of wool fabrics.

Detailed ways

The embodiments of the present invention are described in detail below. This embodiment is implemented on the premise of the technical solution of the invention, and provides a detailed embodiment and a specific operation process, but the protection scope of the present invention is not limited to the following implementation. example. The experimental programs without specific conditions in the examples are usually implemented in accordance with the conventional conditions or the conditions suggested by the manufacturer.

Example 1

A kind of cationic carbon black, its concrete preparation process is as follows:

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add a certain amount of epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add dodecyl tertiary amine, stop heating after quaternization at 50 ^oC for 2 hours, and obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and dodecyl tertiary amine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed in water to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +40.0mv.

Fig. 1 is the infrared spectrum of the intermediate product CB@SiO2 composite prepared in this example 1, the CB@SiO2 composite covalently modified by epichlorohydrin and the final product cationic carbon black. It can be seen from the comparison that epichlorohydrin The characteristic peak of the three-membered ring does not appear in the infrared of the modified complex, but the characteristic peak of -CH2- appears, and the hydroxyl peak is strengthened, indicating that epichlorohydrin undergoes a ring-opening reaction and is covalently grafted to the complex. surface. The -CH2- peak of cationic carbon black was strengthened, and the C-N peak appeared at the same time, indicating that the tertiary amine was involved in the quaternization reaction.

Figure 3b is the thermogravimetric curve of the cationic carbon black of Example 1. The weight loss of the cationic components on the surface of the cationic carbon black is between 120 and 530 ^o C. It can be seen that the proportion of the cationic components is relatively large.

Example 2

A kind of cationic carbon black, its concrete preparation process is as follows:

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: adding epichlorohydrin to the above reaction solution, stirring at 50 ^oC for 2 hours, then adding 3-dimethylaminopropylamine, quaternizing at 50 ^oC for 2 hours, and stopping heating to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and 3-dimethylaminopropylamine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed in water to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +52.0mv.

Example 3

A kind of cationic carbon black, its concrete preparation process is as follows:

Step 1: Take 1g of nano-carbon black (average particle size 24nm) and 3ml of concentrated ammonia water (25% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: adding epichlorohydrin to the above reaction solution, stirring at 50 ^° C for 2h, then adding dodecyl tertiary amine, quaternizing reaction at 50 ^°C for 2h, and stopping heating to obtain a cationic carbon black suspension. The molar ratio of tetraethylorthosilicate, epichlorohydrin and dodecyltetradecylamine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed in water to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +46.4mv.

Example 4

A kind of cationic carbon black, its concrete preparation process is as follows:

Step 1: Take 1g of nano-carbon black (average particle size 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add epichlorohydrin to the above reaction solution, stir at 50 ^° C for 2h, then add hexadecyl tertiary amine, stop heating after quaternization at 50 ^°C for 2h to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and hexadecyl tertiary amine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +43.8mv.

Example 5

A kind of cationic carbon black, its concrete preparation process is as follows:

The first step: take 1g of nano-carbon black (average particle size 16nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of absolute ethanol, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3ml of tetraethyl orthosilicate in 10ml of anhydrous ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2h.

The second step: add epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add dodecyl tertiary amine, stop heating after quaternization reaction at 50 ^oC for 2 hours, and obtain a cationic carbon black suspension. The molar ratio of tetraethylorthosilicate, epichlorohydrin and dodecyltetradecylamine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed in water to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +47.9mv.

Example 6

A kind of cationic carbon black, its concrete preparation process is as follows:

Step 1: Take 1g of nano-carbon black (average particle size 30nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of absolute ethanol, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of anhydrous ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add dodecyl tertiary amine, stop heating after quaternization reaction at 50 ^oC for 2 hours, and obtain a cationic carbon black suspension. The molar ratio of tetraethylorthosilicate, epichlorohydrin and dodecyltetradecylamine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +41.4mv.

Example 7

A kind of cationic carbon black, its concrete preparation process is as follows:

The first step: take 1g of nano-carbon black (average particle size 45nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of absolute ethanol, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 4 ml of tetraethyl orthosilicate in 10 ml of anhydrous ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add dodecyl tertiary amine, stop heating after quaternization reaction at 50 ^oC for 2 hours, and obtain a cationic carbon black suspension. The molar ratio of tetraethylorthosilicate, epichlorohydrin and dodecyltetradecylamine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +56.2mv.

Example 8

A kind of cationic carbon black, its concrete preparation process is as follows:

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 4ml of concentrated ammonia water (25% by mass) in 40ml of 80% ethanol aqueous solution, stir well for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of anhydrous ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 1 h.

The second step: add epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add dodecyl tertiary amine, stop heating after quaternization reaction at 60 ^oC for 2 hours, and obtain a cationic carbon black suspension. The molar ratio of tetraethylorthosilicate, epichlorohydrin and dodecyltetradecylamine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed in water to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +37.0mv.

Example 9

A kind of cationic carbon black, its concrete preparation process is as follows:

The first step: take 1g of nano-carbon black (average particle size 24nm) and 1ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 2 ml of tetraethyl orthosilicate in 10 ml of anhydrous ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 3 hours.

The second step: add epichlorohydrin to the above reaction solution, stir at 50 ^oC for 2 hours, then add dodecyl tertiary amine amine, stop heating after quaternization at 70 ^oC for 1 hour, and obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and dodecyl tertiary amine is 1:2:2.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed in water to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +48.0mv.

Example 10

A kind of cationic carbon black, its concrete preparation process is as follows:

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of absolute ethanol, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of anhydrous ethanol solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add epichlorohydrin to above-mentioned reaction solution, 50^oCStir the reaction for 1h, then add dodecyl tertiary amine, 50 ^oCAfter the quaternization reaction for 1 h, the heating was stopped to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and dodecyl tertiary amine is 1:1.5:1.5.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed in water to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +35.5mv.

Example 11

A kind of cationic carbon black, its concrete preparation process is as follows:

The first step: take 1g of nano-carbon black (average particle size of 16nm) and 3ml of concentrated ammonia water (27% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 4 ml of tetraethyl orthosilicate in 10 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 3 hours, then add dodecyl tertiary amine, stop heating after quaternization reaction at 50 ^oC for 3 hours, and obtain a cationic carbon black suspension. The molar ratio of tetraethylorthosilicate, epichlorohydrin and dodecyltetradecylamine is 1:1.1:1.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +24.6mv.

Example 12

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add a certain amount of epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add arginine ethyl ester hydrochloride, and stop heating after 50 ^oC reaction for 3 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and ethyl arginine hydrochloride is 1:1.1:1.

The third step: the above suspension is centrifuged and washed until the pH is neutral, and then dispersed in water to adjust the pH of the solution to 4-5 to obtain a cationic carbon black dispersion, which is dried to obtain a cationic carbon black powder. The dispersibility of cationic carbon black is weakly cationic, and the zeta potential is +23.4mv.

Example 13

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add a certain amount of epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add arginine, and stop heating after 50 ^oC reaction for 3 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and arginine is 1:1.1:1.

The third step: the above suspension is centrifuged and washed until the pH is neutral, and then dispersed in water to adjust the pH of the solution to 4-5 to obtain a cationic carbon black dispersion, which is dried to obtain a cationic carbon black powder. The dispersibility of cationic carbon black is weakly cationic, and the zeta potential is +26.8mv.

Example 14

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: add a certain amount of epichlorohydrin to the above reaction solution, stir and react at 50 ^oC for 2 hours, then add arginine hydrochloride, and stop heating after 50 ^oC reaction for 3 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and arginine is 1:1.1:1.

The third step: the above suspension is centrifuged and washed until the pH is neutral, and then dispersed in water to adjust the pH of the solution to 4-5 to obtain a cationic carbon black dispersion, which is dried to obtain a cationic carbon black powder. The dispersibility of cationic carbon black is weakly cationic, and the zeta potential is +25.3mv.

Example 15

Step 1: Take 1g of nano-carbon black (average particle size 24nm) and 3ml of concentrated ammonia water (25% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: adding a certain amount of epichlorohydrin to the above reaction solution, stirring and reacting for 2 hours, then adding dodecyl tertiary amine, and stopping heating after reacting for 2 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and dodecyl tertiary amine is 1:0.55:0.5.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +18.1mv.

Example 16

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: adding a certain amount of epichlorohydrin to the above reaction solution, stirring and reacting for 2 hours, then adding dodecyl tertiary amine, and stopping heating after reacting for 2 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and dodecyl tertiary amine is 1:1.1:1.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +23.5mv.

Example 17

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: adding a certain amount of epichlorohydrin to the above reaction solution, stirring and reacting for 2 hours, then adding dodecyl tertiary amine, and stopping heating after reacting for 2 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate, epichlorohydrin and dodecyl tertiary amine is 1:1.5:1.5.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +30.5mv.

Figure 3a is the thermogravimetric curve of the cationic carbon black of this example, the weight loss of the cationic components on the surface of the cationic carbon black is between 120-530 ^o C, and it can be seen that the proportion of the cationic components is relatively large.

Example 18

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: adding a certain amount of epichlorohydrin to the above reaction solution, stirring and reacting for 2 hours, then adding dodecyl tertiary amine, and stopping heating after reacting for 2 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate and epichlorohydrin is 1:2.5:2.5.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +60.2mv.

Figure 2 is the TEM image of the cationic carbon black of this example, and it can be seen that the average particle size of the cations is 45 nm.

Figure 3c is the thermogravimetric curve of the cationic carbon black of this example, the weight loss of the cationic components on the surface of the cationic carbon black is between 120 and 530 ^o C, and it can be seen that the proportion of the cationic components is relatively large.

The coloring properties of cationic carbon black synthesized under optimized process conditions and pure carbon black were compared:

The synthetic cationic carbon black and the unmodified pure carbon black were respectively formulated into black pigments with a mass fraction of 2% to color wool fabrics respectively. The dye-to-bath ratio was 1:50, the amount of pigment was 10% owf., the pH of the dye solution was adjusted to 9 with ammonia, and the temperature was raised to 80 ^o C for 30 minutes at 45 ^oC for coloring for 30 minutes. Cool, wash and dry with tap water for several times, then wash and dry with 5% soap solution, and observe the color change.

Figure 4 illustrates that the coloring properties of cationic carbon blacks are superior to those of unmodified pure carbon blacks. A is wool dyed with cationic carbon black, and B is wool dyed with pure carbon black, in which (a)-(d) in A are pure wool, wool dyed with cationic carbon black, and wool samples after washing several times , Wool samples after soaping; (a)-(d) in B are pure wool, wool colored by pure carbon black, wool samples after washing several times, and wool samples after soaping. .

Example 19

Step 1: Take 1g of nano-carbon black (average particle size: 24nm) and 3ml of concentrated ammonia water (28% by mass) in 40ml of 95% ethanol aqueous solution, fully stir for 1h, and heat up to 50 ^oC after mixing evenly. Dissolve 3 ml of tetraethyl orthosilicate in 8 ml of 95% ethanol aqueous solution, shake and mix evenly, then add the above carbon black suspension dropwise, and react for 2 hours.

The second step: adding a certain amount of epichlorohydrin to the above reaction solution, stirring and reacting for 2 hours, then adding dodecyl tertiary amine, and stopping heating after reacting for 2 hours to obtain a cationic carbon black suspension. The molar ratio of tetraethyl orthosilicate and epichlorohydrin is 1:3:3.

The third step: the above suspension is centrifuged and washed until the pH is neutral, then dispersed to obtain a cationic carbon black dispersion, and dried to obtain a cationic carbon black powder. The zeta potential of the cationic carbon black dispersion was +46.0mv.

Figure 3d is the thermogravimetric curve of the cationic carbon black of this example, the weight loss of the cationic components on the surface of the cationic carbon black is between 120 and 530 ^o C, and it can be seen that the proportion of the cationic components is relatively large.

The above content is only the preferred embodiment of the present invention. For those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific embodiment and application scope. limits.

Claims (5)

1. A preparation method of cation nano carbon black comprises the following specific steps:

A) mixing and stirring a certain amount of nano carbon black, a catalyst and a solvent uniformly, heating and dropwise adding an ethanol solution of tetraethyl orthosilicate for reacting for a certain time; wherein the particle size of the nano carbon black is 15-50 nm; the mass volume ratio of the nano carbon black to the tetraethyl orthosilicate is 1: (2-4) g/mL; wherein the temperature of heating and dripping tetraethyl orthosilicate ethanol solution is 40^oC~60^{o C}(ii) a Reacting for 1-3 h; the molar ratio of tetraethylorthosilicate to epichlorohydrin in step B) is 1: (0.5 to 3);

B) adding epoxy chloropropane into the mixed solution A), keeping the temperature for reaction, then adding tertiary amine or amino acid, and controlling the temperature for quaternization; wherein the molar ratio of the tertiary amine to the epichlorohydrin is 1: (1-1.1); the mol ratio of the amino acid to the epichlorohydrin is 1: (1-1.1); wherein the temperature of the reaction is maintained at 40 deg.C^oC~60^{o C}The reaction time is 1-3 h; the quaternization reaction temperature is 50-70^oC; the reaction time is 1-3 h;

C) and C) centrifuging and washing the cation carbon black mixed solution prepared in the step B) until the pH value is neutral, dispersing in water to obtain a modified cation carbon black dispersion solution, and drying to obtain the cation carbon black.

2. The method according to claim 1, wherein the solvent in step A) is an aqueous ethanol solution having a volume concentration of 80 to 100%.

3. The method according to claim 1, wherein the volume ratio of tetraethyl orthosilicate to ethanol in the tetraethyl orthosilicate ethanol solution in step a) is 1: (2.5-5).

4. The preparation method according to claim 1, wherein the catalyst in step A) is concentrated ammonia water, and the mass concentration of the concentrated ammonia water is 25-28%; the mass volume ratio of the nano carbon black powder to the catalyst is 1: (1-4) g/mL.

5. The method of claim 1, wherein the tertiary amine in step B) is one of dodecyltertiary amine, hexadecyltertiary amine, and 3-dimethylaminopropylamine.

Images