Safe and environment-friendly Paris green substitute pigment as well as preparation method and application thereof

Abstract

The invention discloses a safe and environment-friendly Paris green substitute pigment as well as a preparation method and application thereof, and belongs to the technical field of materials. And weighing 12.5-18.6 parts of modified nano titanium dioxide, 46.5-62.5 parts of art green, 21.9-27.9 parts of peacock blue and 3.1-7.0 parts of fluorescent green 3G, respectively sieving by a 200-mesh sieve, and uniformly stirring to obtain the substitute pigment. The pigment obtained by mixing the modified nano titanium dioxide with other raw materials is similar to the Paris green in color, and can be used as a safe and environment-friendly pigment for replacing the Paris green. The modified nano titanium dioxide contains a benzophenone structure, a quaternary ammonium salt antibacterial structure and a sulfonamide group, so that the modified nano titanium dioxide has excellent ultraviolet resistance and antibacterial activity, and when the modified nano titanium dioxide is added into the pigment, the pigment can be prevented from being damaged by microorganisms and is not prone to decay, mildew and blackening; meanwhile, the weather resistance of the pigment is greatly enhanced, the color stability of the pigment is maintained, and the service life of the pigment is prolonged.

Description

Technical Field

[0001] The present invention belongs to the field of material technology, and in particular, relates to a safe and environmentally friendly Paris green alternative pigment and a preparation method and application thereof. Background Art

[0002] Paris green, with the molecular formula of Cu(C2H3O2)2·3Cu(AsO2)2, is blue in color, rich in hue, and magnificent. It is the main pigment for painting green in large quantities. However, Paris green is expensive and highly toxic. The use of the pigment will cause dust, which can cause acute local effects and chronic poisoning caused by arsenic if inhaled through the respiratory tract or ingested through the mouth. Therefore, Paris green seriously threatens the health of construction workers in actual use, and there is an urgent need to prepare a safe and environmentally friendly Paris green alternative pigment.

[0003] During use, pigments are exposed to the air for a long time and are easily contaminated by microorganisms such as bacteria, fungi, mold, and yeast, which can cause the pigments to become corrupt, moldy, and thin, which not only affects the appearance and quality of the pigments, but may also affect their use and life. In addition, long-term ultraviolet radiation can also seriously affect the performance and service life of the pigments. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a safe and environmentally friendly Paris green alternative pigment and a preparation method and application thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A safe and environmentally friendly Paris green alternative pigment comprises the following raw materials in parts by weight: 12.5-18.6 parts of modified nano titanium dioxide, 46.5-62.5 parts of art green, 21.9-27.9 parts of peacock blue, and 3.1-7.0 parts of fluorescent green 3G.

[0007] Furthermore, the safe and environmentally friendly Paris green alternative pigment comprises the following raw materials in parts by weight: 16.4 parts of modified nano titanium dioxide, 54.8 parts of art green, 23.3 parts of peacock blue, and 5.5 parts of fluorescent green 3G.

[0008] Furthermore, the modified nano titanium dioxide is prepared by the following steps:

[0009] S1. Under nitrogen protection, 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid, thionyl chloride and carbon tetrachloride were added to a dry three-necked flask, stirred and heated to 65°C, and kept warm for 1 hour. After the reaction was completed, it was cooled to room temperature, allowed to stand for stratification, and the lower layer of liquid was taken out. Crystals were precipitated with ice water, filtered, and washed with deionized water until the filtrate was neutral. The filter residue was dried at 80°C for 12 hours to obtain intermediate 1; the dosage ratio of 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid, thionyl chloride and carbon tetrachloride was 24.7g:6.4mL:120mL;

[0010] Under heating conditions, the molar ratio of 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid and thionyl chloride is controlled to be 1:1.1-1.2, then 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid and thionyl chloride undergo a chlorination reaction, and the reaction process is as follows:

[0011]

[0012] S2. Under nitrogen protection, add intermediate 1, 1,3-propylenediamine and DMSO (dimethyl sulfoxide) to a dry three-necked flask, stir and dissolve, cool the system to 10°C in an ice bath, slowly add triethylamine, raise the temperature to 50°C and stir to react for 6h after the addition is complete, cool to room temperature after the reaction is completed, and distill under reduced pressure to obtain intermediate 2; the usage ratio of intermediate 1, 1,3-propylenediamine, triethylamine and DMSO is 24.5g:6.7mL:12.5mL:180mL;

[0013] The molar ratio of intermediate 1 and 1,3-propylenediamine is controlled to be 1:1.05-1.1. Under heating, the sulfonyl chloride of intermediate 1 and the amino group of 1,3-propylenediamine undergo amidation reaction to generate intermediate 2 containing a sulfonamide group. Triethylamine is an acid binding agent and promotes the forward reaction. The reaction process is shown below:

[0014]

[0015] S3, under nitrogen protection, add intermediate 2, tetradecane bromide and DMSO (dimethyl sulfoxide) into a dry three-necked flask, stir and dissolve, then add pyridine, after adding, heat to 70°C and react for 3h, cool to room temperature after the reaction, and distill under reduced pressure to obtain intermediate 3; the amount ratio of intermediate 2, tetradecane bromide, pyridine and DMSO is 23.7g:40.8mL:11.6mL:200mL;

[0016] The molar ratio of intermediate 2 and tetradecane bromide is controlled to be 1:2.1-2.2. Under heating, -NH2 of intermediate 2 and -Br of tetradecane bromide undergo nucleophilic substitution reaction, and pyridine is an acid binding agent. The reaction process is as follows:

[0017]

[0018] S4, nitrogen was blown into a dry three-necked flask for 30 minutes to expel air and moisture in the flask, and then intermediate 3, chloropropyltrimethoxysilane and DMF (N,N-dimethylformamide) were added, and triethylamine was slowly added after stirring to dissolve. After the addition was completed, the temperature was raised to 80°C and stirred for reaction for 3 hours. After the reaction was completed, it was cooled to room temperature and distilled under reduced pressure to obtain intermediate 4; the amount ratio of intermediate 3, chloropropyltrimethoxysilane, triethylamine and DMSO was 30.3 g:7.9 mL:7.2 mL:200 mL;

[0019] The molar ratio of intermediate 3 and chloropropyltrimethoxysilane is controlled to be 1:1.05-1.1. Under heating, the tertiary amine of intermediate 3 and -Cl of chloropropyltrimethoxysilane undergo nucleophilic substitution reaction, and triethylamine is an acid binding agent. The reaction process is as follows:

[0020]

[0021] S5. Add nano titanium dioxide and deionized water into a three-necked flask, stir evenly, slowly add concentrated hydrochloric acid, adjust the pH value to 5, heat to 65°C, slowly add the mixed solution of intermediate 4 and DMF, react at 65°C for 10h after the addition, cool to room temperature after the reaction, filter, wash with anhydrous ethanol 5 times, and vacuum dry at 80°C for 12h to obtain modified nano titanium dioxide. The mass ratio of nano titanium dioxide to intermediate 4 is 15:1.

[0022] The trimethoxysilane on the intermediate 4 can be hydrolyzed and then condensed to form Si-O-Si and Si-OH; the hydroxyl group in the silanol group can form a hydrogen bond with the hydroxyl group on the surface of the nano-titanium dioxide, and then dehydrate and condense to form a covalent bond, thereby forming a chemical bond between the intermediate 4 and the nano-titanium dioxide, and the intermediate 4 is firmly present on the surface of the nano-titanium dioxide.

[0023] The intermediate 4 has a benzophenone structure, a quaternary ammonium salt antibacterial structure (containing two long carbon chains with 14 carbon atoms) and a sulfonamide group. Therefore, the modified nano-titanium dioxide also has these structures or groups.

[0024] Benzophenone structures can strongly absorb 290-400nm ultraviolet light and release the absorbed energy in the form of heat or low-energy radiation to prevent ultraviolet damage to the pigment. This structure has the advantages of high ultraviolet absorption rate, non-toxicity, no teratogenicity, and good light and heat stability.

[0025] The quaternary ammonium salt structure dissociates into a positively charged quaternary ammonium salt cation in aqueous solution—N +Ions can be adsorbed onto the cell walls of negatively charged bacteria, thereby destroying bacterial cell membranes and denaturing their proteins, hindering DNA replication and reproduction, etc., thereby achieving antibacterial effects. In addition, when the number of carbon atoms in the alkyl chain of the quaternary ammonium salt structure is 10-16, especially when the number of carbon atoms is 14, the antibacterial effect is the best. The sulfonamide structure is the pharmacophore of antibacterial compounds, so the sulfonamide structure enhances the antibacterial activity of quaternary ammonium salts.

[0026] Therefore, the modified nano titanium dioxide of the present invention has excellent UV resistance and antibacterial activity. Adding it to the pigment can protect the pigment from microbial invasion, and is not easy to corrupt, mold and blacken. At the same time, it greatly enhances the weather resistance of the pigment, maintains the color stability of the pigment and prolongs the service life of the pigment.

[0027] A method for preparing a safe and environmentally friendly Paris green alternative pigment comprises the following steps:

[0028] Weigh each raw material by weight and pass them through a 200-mesh sieve respectively, then add all the raw materials into a blender and stir, and after mixing evenly, a safe and environmentally friendly Paris green alternative pigment can be obtained.

[0029] The invention also discloses the use of a safe and environmentally friendly Paris green alternative pigment in the coloring of wallpapers and ancient buildings.

[0030] The invention has the beneficial effects that the pigment obtained by mixing the modified nano titanium dioxide with other raw materials is similar to Paris green in color and can be used as a safe and environmentally friendly pigment to replace Paris green. The modified nano titanium dioxide has a benzophenone structure, a quaternary ammonium salt antibacterial structure and a sulfonamide group, so the modified nano titanium dioxide has excellent ultraviolet resistance and antibacterial activity. Adding the modified nano titanium dioxide to the pigment can protect the pigment from microbial damage, prevent corruption, mildew and blackening, and greatly enhance the weather resistance of the pigment, maintain the color stability of the pigment and extend the service life of the pigment. DETAILED DESCRIPTION

[0031] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Example 1

[0033] The specific steps for preparing modified nano titanium dioxide are as follows:

[0034] S1. Under nitrogen protection, add 24.7 g of 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid, 6.4 mL of thionyl chloride and 120 mL of carbon tetrachloride into a 250 mL dry three-necked flask, stir and heat to 65 ° C, keep warm for 1 hour, cool to room temperature after the reaction, stand and separate, take the lower layer of liquid, use ice water to precipitate crystals, then filter, wash with deionized water until the filtrate is neutral, and dry the residue at 80 ° C for 12 hours to obtain intermediate 1;

[0035] S2, under nitrogen protection, add 24.5g of intermediate 1, 6.7mL of 1,3-propylenediamine and 180mL of DMSO into a 500mL dry three-necked flask, stir to dissolve, cool the system to 10°C in an ice bath, and then slowly add 12.5mL of triethylamine. After the addition is complete, heat to 50°C and stir to react for 6h. After the reaction is completed, cool to room temperature and distill under reduced pressure to obtain intermediate 2;

[0036] S3, under nitrogen protection, add 23.7 g of intermediate 2, 40.8 mL of tetradecane bromide and 200 mL of DMSO into a 500 mL dry three-necked flask, stir to dissolve, then add 11.6 mL of pyridine, after adding, heat to 70°C and react for 3 h, after the reaction is completed, cool to room temperature, and distill under reduced pressure to obtain intermediate 3;

[0037] S4, nitrogen was blown into a 500 mL dry three-necked flask for 30 min to expel air and moisture in the flask, then 30.3 g of intermediate 3, 7.9 mL of chloropropyltrimethoxysilane and 200 mL of DMF were added, and 7.2 mL of triethylamine was slowly added after stirring to dissolve. After the addition was completed, the temperature was raised to 80 ° C and stirred for reaction for 3 h. After the reaction was completed, the mixture was cooled to room temperature and distilled under reduced pressure to obtain intermediate 4;

[0038] S5. Add 45g of nano titanium dioxide and 200mL of deionized water into a 500mL three-necked flask, stir well, then slowly add concentrated hydrochloric acid, adjust the pH value to 5, heat to 65°C, and then slowly add a mixed solution of 3g of intermediate 4 and 20mL of DMF. After the addition is completed, react at 65°C for 10h. After the reaction is completed, cool to room temperature, filter, wash with anhydrous ethanol 5 times, and vacuum dry at 80°C for 12h to obtain modified nano titanium dioxide.

[0039] Example 2

[0040] Preparation of Paris Green Alternative Pigment, the specific steps are as follows:

[0041] Weigh each raw material by weight and pass them through a 200-mesh sieve respectively. Then add 12.5 parts of the modified nano titanium dioxide prepared in Example 1, 62.5 parts of art green, 21.9 parts of peacock blue and 3.1 parts of fluorescent green 3G into a blender and stir. After mixing evenly, the Paris green alternative pigment can be obtained.

[0042] Example 3

[0043] Preparation of Paris Green Alternative Pigment, the specific steps are as follows:

[0044] Weigh each raw material by weight and pass them through a 200-mesh sieve respectively. Then add 18.6 parts of the modified nano titanium dioxide prepared in Example 1, 46.5 parts of art green, 27.9 parts of peacock blue and 7.0 parts of fluorescent green 3G into a blender and stir. After mixing evenly, the Paris green alternative pigment can be obtained.

[0045] Example 4

[0046] Preparation of Paris Green Alternative Pigment, the specific steps are as follows:

[0047] Weigh each raw material by weight and pass them through a 200-mesh sieve respectively. Then add 16.4 parts of the modified nano titanium dioxide prepared in Example 1, 54.8 parts of art green, 23.3 parts of peacock blue, and 5.5 parts of fluorescent green 3G into a blender and stir. After mixing evenly, the Paris green alternative pigment can be obtained.

[0048] Comparative Example 1

[0049] Preparation of Paris Green Alternative Pigment, the specific steps are as follows:

[0050] The remaining steps remain unchanged, only the modified nano titanium dioxide in Example 4 is replaced by nano titanium dioxide without any treatment, so as to prepare the Paris green alternative pigment.

[0051] Comparative Example 2

[0052] Preparation of Paris Green Alternative Pigment, the specific steps are as follows:

[0053] The remaining steps remain unchanged, except that the modified nano titanium dioxide in Example 4 is replaced by 15.4 parts of untreated nano titanium dioxide, 0.5 parts of ultraviolet absorber UV-531 and 0.5 parts of didodecyl dimethyl ammonium chloride, thereby preparing a Paris green alternative pigment.

[0054] Performance Testing

[0055] The size of the ΔE value reflects the degree of color change (ΔE represents the color difference value, unit NBS). The larger the ΔE value, the greater the color change, and vice versa.

[0056] Table 1 Color difference value and color change comparison table

[0057] ΔE / NBS Color Change 0-0.5 Trace 0.5-1.5 Slight Change 1.5-3.0 Visible changes 3.0-6.0 Obvious changes 6.0-12.0 Big changes 12.0 or above A lot of changes

[0058] The color difference between the Paris green substitute pigments and the Paris green pigment prepared in Examples 2-4 and Comparative Examples 1-2 was tested, and the test results are shown in Table 2 below:

[0059] Table 2

[0060] Test items ΔE / NBS Color Change Example 2 1.22 Slight Change Example 3 1.21 Slight Change Example 4 1.19 Slight Change Comparative Example 1 1.23 Slight Change Comparative Example 2 1.22 Slight Change

[0061] The Paris green substitute pigments prepared in Examples 2-4 and Comparative Examples 1-2 were aged in dry heat, wet heat, and UV aging boxes for 120 hours, respectively, and the color difference between the substitute pigments after aging and before aging was measured. The test conditions are as follows: dry heat aging at 105°C for 120 hours; wet heat aging at 80°C and 60% humidity for 120 hours; UV aging at room temperature, vertical irradiation distance of 20 cm, and 30W UV lamp for 120 hours; the test results are shown in Table 3 below:

[0062] Table 3

[0063]

[0064] The antibacterial property test was carried out according to GB / T21866-2008 "Determination of antibacterial property and antibacterial effect of antibacterial coatings (paint films)". The test results are shown in Table 4 below:

[0065] Table 4

[0066]

[0067] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0068] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A safe and environmentally friendly Paris green alternative pigment, characterized in that: The method comprises the following raw materials in parts by weight: 12.5-18.6 parts of modified nano titanium dioxide, 46.5-62.5 parts of art green, 21.9-27.9 parts of peacock blue, and 3.1-7.0 parts of fluorescent green 3G; Wherein, the modified nano titanium dioxide is prepared by the following steps: S1. Add 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid, thionyl chloride and carbon tetrachloride into a flask under nitrogen protection, react at 65°C for 1 hour, cool, stand and separate, take the lower layer of liquid, use ice water to precipitate crystals, filter, wash and dry to obtain intermediate 1; S2. Under nitrogen protection, add intermediate 1, 1,3-propylenediamine and DMSO into a flask, cool to 10°C, add triethylamine, react at 50°C for 6h, cool, and distill under reduced pressure to obtain intermediate 2; S3, under nitrogen protection, add intermediate 2, tetradecane bromide and DMSO into a flask, stir, add pyridine, react at 70°C for 3h, cool, and distill under reduced pressure to obtain intermediate 3; S4, after nitrogen blowing into the flask, add intermediate 3, chloropropyltrimethoxysilane and DMF, stir, add triethylamine, react at 80°C for 3h, cool, and distill under reduced pressure to obtain intermediate 4; S5. Add nano titanium dioxide and deionized water into a flask, stir, adjust the pH value to 5, heat to 65°C, add intermediate 4 and DMF, react at 65°C for 10 hours, cool, filter, wash, and dry to obtain modified nano titanium dioxide.

2. A safe and environmentally friendly Paris green alternative pigment according to claim 1, characterized in that: The usage ratio of 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid, thionyl chloride and carbon tetrachloride in step S1 is 24.7 g:6.4 mL:120 mL.

3. A safe and environmentally friendly Paris green alternative pigment according to claim 1, characterized in that: The usage ratio of intermediate 1, 1,3-propylenediamine, triethylamine and DMSO in step S2 is 24.5 g: 6.7 mL: 12.5 mL: 180 mL.

4. A safe and environmentally friendly Paris green alternative pigment according to claim 1, characterized in that: The usage ratio of intermediate 2, tetradecane bromide, pyridine and DMSO in step S3 is 23.7 g:40.8 mL:11.6 mL:200 mL.

5. A safe and environmentally friendly Paris green alternative pigment according to claim 1, characterized in that: The usage ratio of intermediate 3, chloropropyltrimethoxysilane, triethylamine and DMSO in step S4 is 30.3 g:7.9 mL:7.2 mL:200 mL.

6. A safe and environmentally friendly Paris green alternative pigment according to claim 1, characterized in that: The mass ratio of nano-titanium dioxide to intermediate 4 in step S5 is 15:

1.

7. A safe and environmentally friendly Paris green alternative pigment according to claim 1, characterized in that: The safe and environmentally friendly Paris green alternative pigment comprises the following raw materials in parts by weight: 16.4 parts of modified nano titanium dioxide, 54.8 parts of art green, 23.3 parts of peacock blue, and 5.5 parts of fluorescent green 3G.

8. The method for preparing a safe and environmentally friendly Paris green alternative pigment according to claim 1, characterized in that: The following steps are involved: Weigh each raw material by weight and pass them through a 200-mesh sieve respectively, then add all the raw materials into a blender and stir, and after mixing evenly, a safe and environmentally friendly Paris green alternative pigment can be obtained.

9. Use of the safe and environmentally friendly Paris green alternative pigment according to claim 1 in coloring wallpapers and ancient buildings.

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