CN110527324B

CN110527324B - Visible light photocatalytic functional treatment liquid for wood lacquer coating surface and preparation method thereof

Info

Publication number: CN110527324B
Application number: CN201910772248.2A
Authority: CN
Inventors: 吴立新; 吴梓坚; 吕君; 毛文阳; 吴晗
Original assignee: Jiangyin Tianbang Quantum Coating Technology Co ltd
Current assignee: Jiangyin Tianbang Quantum Coating Technology Co ltd
Priority date: 2019-08-21
Filing date: 2019-08-21
Publication date: 2021-09-14
Anticipated expiration: 2039-08-21
Also published as: CN110527324A

Abstract

The invention discloses a visible light photocatalytic function treating fluid for a wood lacquer coating surface and a preparation method thereof, wherein the visible light photocatalytic function treating fluid comprises the following components in percentage by weight: 1-10% of silica sol, 0.1-2% of organic silicon modified waterborne alkyd emulsion, 1-10% of titanium dioxide quantum dots doped with noble metal ions, 0.02-1% of silicon nanoparticles, 0-0.5% of FeOOH nanoparticles, 0.1-1% of dispersing agent, 0.1-1% of thickening agent, 0.1-1% of defoaming agent, 0.01-0.3% of pH value regulator and the balance of water. Compared with the traditional photocatalytic coating, the visible light photocatalytic functional treatment liquid for the surface of the wood lacquer coating can obviously improve the photocatalytic effect, can continuously and efficiently remove harmful substances such as formaldehyde, benzene, ammonia, TVOC, PM2.5 and the like, and can kill bacteria, viruses, fungi, microorganisms and the like in a broad spectrum.

Description

Visible light photocatalytic functional treatment liquid for wood lacquer coating surface and preparation method thereof

Technical Field

The invention relates to the field of coatings, in particular to visible light photocatalytic functional treatment fluid for a wood lacquer coating surface and a preparation method thereof.

Background

Since the discovery of the photodecomposition phenomenon of titanium dioxide single crystal under ultraviolet irradiation in 1972 by Taeniculia of photochemistry, photocatalysis has gradually become a novel environment-friendly environmental pollution cleaning technology. The photocatalyst absorbs light, electrons on the surface of the photocatalyst absorb enough energy to be separated, positive holes are formed at the positions where the electrons are separated, the electrons and the holes react with oxygen, water and hydroxyl groups to generate superoxide ions with strong oxidizing property and hydroxyl radicals with strong reducing property, and the superoxide ions and the hydroxyl radicals oxidize and decompose organic pollutants and bacteria into harmless water and carbon dioxide, so that the aims of removing pollutants and reducing bacteria are fulfilled.

There are many photocatalyst materials, and titanium dioxide is currently the most important photocatalyst material because of its strong oxidizing ability, chemical stability and non-toxicity. The photocatalyst adopted by the anti-formaldehyde odor-removing full-effect environment-friendly water-based woodenware white paint disclosed in CN102146257B is nano titanium dioxide. However, the forbidden band width of the titanium dioxide is large, and the photocatalyst has higher catalytic activity only under the irradiation of ultraviolet light; for visible light with the most significant solar energy of 400-700nm, the titanium dioxide has weak responsiveness, does not have catalytic activity basically in the visible light range, and has low utilization rate for the visible light.

In order to improve the responsiveness of titanium dioxide to visible light, patent publication No. CN102277051B proposes a method of doping titanium dioxide with a nonmetal such as carbon in a coating, but the visible light-responsive photocatalyst obtained in this way has weak light absorption capability, low catalytic activity, easy loss of doping elements, and easy loss of catalytic activity. In this method, the photosensitive dye as an active component is an organic substance, and the chemical bond thereof is decomposed and isolated by photocatalysis, so that the responsiveness to visible light is not durable, and the lifetime of the photosensitive dye gradually decreases with the passage of time. The patent publication No. CN1013756376B proposes that a semiconductor with a narrow forbidden band width such as modified iron oxide is added to absorb visible light, the refractive index of the iron oxide material is high, generally 2.8-2.9, and the contrast refractive index is generally only about 1.4-1.6 for a coating substrate, and iron oxide particles scatter visible light strongly, so that the defect of low visible light catalytic activity exists. In addition, the document also proposes that semiconductors with narrow energy gap widths such as cadmium sulfide and tin dioxide are added, but the cadmium sulfide and the tin dioxide have certain toxicity and cannot meet the requirement of environmental protection.

Further, these photocatalytic coatings have the following problems.

Firstly, the photocatalytic effect is limited because light absorption is basically concentrated on the surface of the coating; how to improve the photocatalytic efficiency of the coating is also an urgent problem to be solved.

And secondly, organic components in the coating are inevitably subjected to bond breaking under the photocatalysis. For example, for wood lacquer, the coating base material is organic polyester or polyurethane resin, the structure is mainly C-C bond, and bond breaking can occur under the photocatalysis. How to avoid the deterioration of the coating layer is extremely important for the long-term stable exertion of the photocatalytic effect.

Disclosure of Invention

The invention aims to overcome the defects and provide the visible light photocatalytic functional treatment liquid for the surface of the wood lacquer coating, which can protect the original wood lacquer coating, has high self photocatalytic efficiency, good visible light responsiveness and stable performance.

The invention also aims to provide a preparation method of the visible light photocatalytic functional treatment liquid for the surface of the wood lacquer coating, which is used for protecting the wood lacquer coating, has high self-photocatalytic efficiency, good visible light responsiveness and stable performance.

One of the objects of the invention is achieved by: the visible light photocatalysis function treating fluid for the surface of the wood lacquer coating comprises the following components in percentage by weight:

the titanium dioxide is doped with the noble metal ions, and the titanium dioxide particles are subjected to quantum dot formation, so that the titanium dioxide has responsiveness to visible light; the added silicon nanoparticles are used for converting ultraviolet light and low-wavelength visible light into high-wavelength visible light, so that titanium dioxide in a system can absorb natural light from the environment and can also receive self-generated visible light from the visible light photocatalytic function treatment liquid after the treatment liquid is cured into a film, the photocatalytic effect of the coating is limited to a light source absorbed by the surface of the coating, the light absorption efficiency is greatly improved, and the catalytic efficiency is greatly improved.

In addition, the surface of the wood lacquer coating is coated with the visible light photocatalytic functional treatment liquid, the silica sol with large bond energy and good weather resistance and high temperature resistance is selected as a base material, the silica sol has low viscosity and strong permeability, can be fully soaked and adhered to a wood lacquer base layer constructed by the silica sol, and seals pores of an original coating to protect the original wood lacquer coating from photodegradation. And a rigid microporous framework structure is formed after the silica sol is formed into a film, so that a microenvironment for adsorbing external toxic organic matters is formed, and the photocatalysis efficiency is improved; the brittleness of the coating after film forming can be reduced by a small amount of organic silicon modified waterborne alkyd resin, so that the coating has good usability; the water-based alkyd resin introduces an organic siloxane chain segment, so that the aging resistance and stability of the water-based alkyd resin are improved, and a coating formed by the visible light photocatalytic treatment solution after film formation is well bonded with a woodware paint base coating.

The further preferable technical scheme is that the particle size of the titanium dioxide quantum dots is 2-10 nm. Here, the noble metal is one of Pt, Au, and Pd.

In the formula, the silicon nanoparticles have rich resources, low price and no toxicity to human bodies, and Si-H bonds are arranged on the surfaces of the silicon nanoparticles and can generate Si-OH and Si-O-Si bonds which are well compatible with silica sol when meeting water. Bulk silicon can only fluoresce weakly. The preferable technical scheme is that the particle size of the silicon nano-particles is less than 8 nm. When the particle size of the silicon nano particles is less than 8nm, the fluorescence effect is enhanced, and the visible light photocatalysis treatment fluid has higher photocatalysis performance.

In order to improve the photocatalytic effect, the preferable technical scheme is that the weight percentage of the FeOOH nano particles is 0.02-0.5%. The FeOOH nano particles can absorb visible light to generate photoproduction electrons and photoproduction holes, and can endow the photoproduction electrons with higher reduction capability by matching with the noble metal ions doped with the titanium dioxide quantum dots, widen the absorption wavelength range of the visible light and improve the photocatalytic activity. It is preferred here that the FeOOH nanoparticles have a particle size of less than 20 nm.

The preferable technical scheme is that the silica sol is alkaline silica sol, and the particle size is 5-100 nm. The alkaline silica sol is more suitable for being used as a coating and has the advantages of good caking property, low shrinkage and the like.

In order to improve the coalescence property of the coating, facilitate construction and improve film-forming property, the preferable technical proposal is that the pH value regulator is 2-amino-2-methyl-1-propanol; the dispersing agent is polyethylene glycol octyl phenyl ether; the thickening agent is a modified polyurethane thickening agent; the defoaming agent is a polyether modified polysiloxane defoaming agent. The nonionic auxiliary agent is not easy to change the pH value of the system, does not influence the condensation of silica sol, and is beneficial to improving the stability of the coating.

The second purpose of the invention is realized by the following steps: a preparation method of visible light photocatalytic functional treatment fluid for the surface of a wood lacquer coating comprises the following steps:

a) adding the silicon nano-particles into water for activation and then stirring for later use; adding titanium dioxide quantum dots doped with noble metal ions and FeOOH nano particles according to the proportion, and ball-milling uniformly by using a ball mill to form a suspension;

b) adding silica sol into the suspension obtained in the step a), and ball-milling uniformly by using a ball mill; and adding a dispersing agent, a thickening agent, a defoaming agent, a pH value regulator and the organic silicon modified water-based alkyd emulsion, uniformly ball-milling to obtain visible light photocatalytic functional treatment liquid for the surface of the wood paint coating, and packaging.

The process disperses silicon nano particles in water to form Si-OH and Si-O-Si bonds compatible with silica sol, then mixes the silicon nano particles with titanium dioxide quantum dots doped with noble metal ions and FeOOH nano particles, and then mixes the silicon nano particles with organic components; based on similar compatibility, the periphery of the photocatalytic active component is surrounded by silica sol, so that the organic components in the coating are isolated and protected, and the performance of the coating is more stable.

The visible light photocatalytic treatment liquid can be directly constructed on the surface of the original wood lacquer coating to form a protective coating capable of protecting the original wood lacquer coating, and the visible light photocatalytic treatment liquid is matched with the protective coating to play a role in isolating and protecting the wood lacquer coating, so that the damage of a photocatalytic degradation process to the latex paint coating is avoided, and the visible light photocatalytic treatment liquid has a good photocatalytic effect.

Compared with the traditional photocatalytic coating, the visible light photocatalytic functional treatment liquid for the surface of the wood lacquer coating has the following advantages.

(1) The photocatalysis effect can be obviously improved. Because the noble metal ions are doped with titanium dioxide quantum dots, silicon nanoparticles and the like, the photocatalytic reaction activity is improved, the photodecomposition capability is greatly enhanced, the photocatalytic efficiency is improved, the coating is decomposed when light is emitted, and the coating has multispectral responsiveness, so that harmful substances such as formaldehyde, benzene, ammonia, TVOC (total volatile organic compound), PM (particulate matter) 2.5 and the like can be continuously and efficiently removed, the indoor air environment is purified, the haze is removed outdoors, the removal rate of volatile organic compounds can reach more than 90%, bacteria, viruses, fungi, microorganisms and the like can be killed in a broad spectrum, and the killing rate of virus protobacteria such as cold viruses and the like can reach more than 90%.

(2) The visible light photocatalytic functional treatment liquid has long photocatalytic service life and stable coating performance, is coated once and used for the whole life, and can also protect the original wood lacquer coating from photodegradation to a great extent.

(3) And (3) food-grade safety: the coating can decompose harmful substances to clean air purely by means of sunlight or illumination, can realize active air purification without any energy consumption, has no secondary pollution, is nontoxic and tasteless, and does not contain substances harmful to the environment.

(4) The coating also has a long-acting self-cleaning effect. The coating has small contact angle and good self-cleaning effect.

Detailed Description

The following further describes the embodiments of the present invention with reference to the accompanying examples. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

Example 1

A visible light photocatalysis function treating fluid for the surface of a wood lacquer coating comprises the following components in percentage by weight:

the preparation method comprises the following steps:

c) adding the silicon nano-particles into water for activation and then stirring for later use; adding titanium dioxide quantum dots doped with noble metal ions according to the proportion, and ball-milling for 0.25-1 hour by using a ball mill at the speed of 70-1500 rpm until the mixture is uniform to form a suspension;

d) adding silica sol into the suspension obtained in the step a), and ball-milling for 0.25-1 hour by using a ball mill until the mixture is uniform; and adding a dispersing agent, a thickening agent, a defoaming agent, a pH value regulator and the organic silicon modified water-based alkyd emulsion, ball-milling for 0.5-6 hours by using a ball mill until the mixture is uniform to obtain visible light photocatalytic functional treatment liquid for the surface of a wood paint coating, filling the visible light photocatalytic functional treatment liquid into a packaging container, and filling nitrogen with the pressure of 0.10-0.13MPa for packaging.

Example 2

The formulation and preparation method in this example are similar to example 1, except that instead of using silicon nanoparticles with a particle size of less than 8nm, silicon nanoparticles with a particle size of 20-200nm are used, and the rest is the same as example 1.

Example 3

the preparation method comprises the following steps:

a) adding the silicon nano-particles into water for activation and then stirring for later use; adding titanium dioxide quantum dots doped with noble metal ions and FeOOH nano particles according to the proportion, and ball-milling for 0.25-1 hour by using a ball mill at the speed of 70-1500 rpm until the mixture is uniform to form a suspension;

b) adding silica sol into the suspension obtained in the step a), and ball-milling for 0.25-1 hour by using a ball mill until the mixture is uniform; and adding a dispersing agent, a thickening agent, a defoaming agent, a pH value regulator and the organic silicon modified water-based alkyd emulsion, ball-milling for 0.5-6 hours by using a ball mill until the mixture is uniform to obtain visible light photocatalytic functional treatment liquid for the surface of a wood paint coating, filling the visible light photocatalytic functional treatment liquid into a packaging container, and filling nitrogen with the pressure of 0.10-0.13MPa for packaging.

Example 4

the preparation method of this example is the same as that of example 3, and is not described herein again.

Example 5

Example 6

Example 7

Comparative example 1

Comparative example 1 is similar to the formulation and preparation method of example 1, except that the formulation of comparative example 1 does not contain silicon nanoparticles. During preparation, the titanium dioxide quantum dots doped with noble metal ions and water are ball-milled for 0.25 to 1 hour by a ball mill at the speed of 70 to 1500 revolutions per minute until the mixture is uniform, so as to form a suspension; adding silica sol into the suspension, and ball-milling for 0.25-1 h by using a ball mill until the mixture is uniform; and adding a dispersing agent, a thickening agent, a defoaming agent, a pH value regulator and the organic silicon modified water-based alkyd emulsion, and ball-milling for 0.5-6 hours by using a ball mill until the mixture is uniform to obtain a photocatalytic functional treatment solution, and packaging.

Comparative example 2

Comparative example 2 is similar to the formulation and preparation method of example 1, and the only difference is that the formulation in comparative example 2 does not contain titanium dioxide quantum dots not containing Au ions. During preparation, after the silicon nano particles are added into water for activation, the silicon nano particles are ball-milled for 0.25 to 1 hour by a ball mill at the speed of 70 to 1500 revolutions per minute until the silicon nano particles are uniform, and a suspension is formed; adding silica sol into the suspension, and ball-milling for 0.25-1 h by using a ball mill until the mixture is uniform; and adding a dispersing agent, a thickening agent, a defoaming agent, a pH value regulator and the organic silicon modified water-based alkyd emulsion, and ball-milling for 0.5-6 hours by using a ball mill until the mixture is uniform to obtain a photocatalytic functional treatment solution, and packaging.

The preparation of the paint film sample plate is carried out according to the GB1727 specification, the material is selected from base paper (inert material is required), and the weight is 80g/m²The preparation method generally adopts a spraying method. And (3) measuring the photolysis index, wherein a light source is LED visible light, the illumination intensity is 145 multiplied by 100LUX, and the methyl blue removal rate is performed according to the GB/T30452-2013. The results are shown in Table 1.

TABLE 1 methyl blue removal rate of coatings obtained in examples 1-7 and comparative examples 1-2

Group of	Methyl blue removal rate (%)
		Example 1	90.9
Example 2	89.9
		Example 3	93.2
Example 4	94.3
		Example 5	89.1
Example 6	93.4
		Example 7	93.7
Comparative example 1	45.7
		Comparative example 2	8.1

As can be seen from table 1, compared with comparative examples 1 and 2 in which only silicon nanoparticles are added to the photocatalytic functional treatment solution, or only titanium dioxide quantum dots doped with noble metal ions are added to the photocatalytic functional treatment solution, the photocatalytic degradation efficiency of examples 1 to 7 of the present invention is significantly improved. Comparing examples 1-3, it can be seen that adding FeOOH nanoparticles, reducing the particle size of the silicon nanoparticles can further improve the photocatalytic degradation efficiency.

The visible light photocatalytic functional treatment liquid for the surface of the wood lacquer coating has good construction performance, can isolate and protect the wood lacquer coating after being coated and formed on the surface of the wood lacquer coating, has the functions of efficiently degrading toxic organic matters and bacteria in the environment by photocatalysis, can efficiently purify indoor air, and has significant and remarkable application prospect in the field of household coating.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The visible light photocatalytic function treatment liquid for the surface of the wood lacquer coating is characterized by comprising the following components in percentage by weight:

2. the visible light photocatalytic functional treatment solution for the wood lacquer coating surface according to claim 1, wherein the particle size of the titanium dioxide quantum dots is 2-10 nm.

3. The visible light photocatalytic functional treatment solution for the wood lacquer coating surface according to claim 1, wherein the noble metal is one of Pt, Au and Pd.

4. The visible light photocatalytic functional treatment solution for the wood lacquer coating surface according to claim 1, wherein the particle size of the silicon nanoparticles is less than 8 nm.

5. The visible light photocatalytic functional treatment fluid for the wood lacquer coating surface according to claim 1, wherein the weight percentage of the FeOOH nanoparticles is 0.02-0.5%.

6. The visible light photocatalytic functional treatment solution for the wood lacquer coating surface according to claim 1, wherein the particle size of the FeOOH nanoparticles is less than 20 nm.

7. The visible light photocatalytic functional treatment solution for the wood lacquer coating surface according to claim 1, wherein the silica sol is an alkaline silica sol, and the particle size is 5-100 nm.

8. The visible light photocatalytic functional treatment solution for the wood lacquer coating surface according to claim 1, wherein the pH regulator is 2-amino-2-methyl-1-propanol; the dispersing agent is polyethylene glycol octyl phenyl ether; the thickening agent is a modified polyurethane thickening agent; the defoaming agent is a polyether modified polysiloxane defoaming agent.

9. The method for preparing the visible light photocatalytic functional treatment fluid for the wood lacquer coating surface according to any one of claims 1 to 8, characterized in that the method comprises the following steps: