CN1321164C - Lyophilic high-molecular antifogging coating and preparing method thereof - Google Patents

Abstract

The present invention relates to antifogging paint which is composed of hydrophilic polymer materials. In the prior art, the paint has the disadvantages of high cost, short antifogging service life, bad cohesive force of the paint and a base material, etc. The present invention uses the hydrophilic polymer materials, a solidifying agent and a curing accelerator to form the antifogging paint according to certain components; the antifogging paint has the advantage of convenient preparation and overcomes the disadvantages of the prior art. The hydrophilic polymer materials are obtained by the polymerization of a nonionic surface active agent (methyl) acrylic ester type monomer, an N-vinyl pyrrolidine, and (methyl) acrylic acid or/ and a (methyl) acrylic ester monomer.

Description

Hydrophilic polymer anti-fog coating and preparation method thereof

technical field

The invention relates to a hydrophilic polymer anti-fog coating and a preparation method thereof.

Background technique

The accumulation of fog on the transparent substrate has attracted more and more people's attention. It may cause inconvenience to people's life, or affect the normal operation of vehicles, and then affect industrial production and economic activities. At present, the research on this kind of anti-fog materials is increasing. In the past, simple anti-fog mirrors usually installed an electric heater on the back of the mirror to drive away the foggy moisture. If the fog cannot be effectively controlled, it will have very adverse consequences.

Zhang Chunxue and others reported that the coating composed of MMA, BMA, HEMA and a small amount of crosslinking agent, N, N-methylene dienamide polymerization has a good anti-fog effect. Li Xuefeng et al added a small amount of crosslinking agent (hexamethoxymethylmelamine, ethylene glycol vinyl dimethyl silane) and surfactant to hydroxyethyl methacrylate, polyethylene glycol methacrylate, and acrylate copolymer. Agents (polyoxyalkylene ethers, alkylbenzene sulfonic acids, etc.) constitute anti-fog coatings. After exploration, Nippon Oils & Oils Co., Ltd. first coats the surface of glass, resin, and plastic with an organic peroxide base layer, and then coats a high-density polymer with hydrophilic groups such as sulfonic acid groups or hydroxyl groups to form a strong chemical bond. A new technology of semi-permanent anti-fog processing has been realized.

The above-mentioned methods all have a certain anti-fog effect, but each method has certain deficiencies, and some methods are not permanent. After some hydrophilic polymers absorb water, not only the anti-fog performance decreases, but also the film cracks due to swelling and softening, so chemical crosslinking is necessary. For this market demand, low-cost, long-life anti-fog coatings suitable for substrates such as glass and transparent resins are developed.

Contents of the invention

The object of the present invention is to provide a low-cost, long-life anti-fog coating.

The purpose of the present invention is to provide a low-cost, long-life anti-fog coating preparation method.

The object of the present invention is to provide a low-cost, long-life curing method for the anti-fog coating.

Hydrophilic macromolecule anti-fog coating of the present invention is made up of hydrophilic macromolecule material, curing agent, curing accelerator, and their components are:

Hydrophilic polymer material: 15～60wt%

Curing agent: 2.0～20wt%

Curing accelerator: 0.1～5.0wt%

Solvent: 30～80wt%

In addition to the above components, you can also add appropriate amount of leveling agent, antioxidant, etc. according to the conventional coating components, and mix well at room temperature before use.

The above-mentioned hydrophilic macromolecular material is: (meth)acrylic acid ester monomer (I) and (meth)acrylic acid or (meth)acrylic acid ester of omega-hydroxyl terminal nonionic surfactant, and hydroxyl-containing (meth)acrylic acid ester (II) copolymer; I, the structural formula of II is as follows:

(I)

R ² = ^* _CH ₂ -CH ₂ -O_ _m R m = 1 to 40

    R″＝-C_nH_2n+1        n＝8～18

R″=-C _n H _2n+1 n=8～18

or R＝-C _n′ H _2n′+1 n′＝1～22

R ¹ is a hydrogen atom or a methyl group

R ³ is a hydrogen atom or a hydrocarbon group containing one to four carbons with a hydroxyl group.

(III)

The monomer of the hydrophilic macromolecular material of the present invention includes: (meth)acrylate of nonionic surfactant, N-vinylpyrrolidone, (meth)acrylic acid or, and hydroxyl-containing (meth)acrylate , curing agent, curing accelerator, and solvent are used to prepare and cure the coating.

Monomers and other components are listed below:

ω-hydroxyl-terminated nonionic surfactant (meth)acrylate (I), such as ω-hydroxyl-terminated dodecyl alcohol ethoxy (n=4) methacrylate, ω-hydroxyl-terminated modification Alkylphenol ethoxy (n=9) acrylate, ω-hydroxyl-terminated polyethylene oxide addition oleyl alcohol (n=20) acrylate, etc.

(Meth)acrylic acid or, and hydroxyl-containing (meth)acrylate (II), such as methacrylic acid, acrylic acid, (2-hydroxyethyl)methacrylate, (2-hydroxyethyl)acrylate, (3-hydroxypropyl) acrylate, (3-hydroxypropyl) methacrylate, etc.

A hydrophilic monomer (IV), such as (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylate or the like.

(Meth)acrylate (V), such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, etc.

Curing agents such as melamine and etherified derivatives, amino alcohol, hexamethylenetetramine, urea, etc., such as tributoxymethyl melamine, hexabutoxymethyl melamine, trimethoxymethyl melamine, hexamethoxy One or more of methylmelamine, amino alcohol, hexamethylenetetramine, urea, etc.

The curing accelerator is an acid or a salt of an acid, such as one or more of acids or ammonium salts of acids such as sulfuric acid, hydrochloric acid, chlorosulfonic acid, p-toluenesulfonic acid, hydrobromic acid, and perchloric acid.

Solvent refers to a solvent that can dissolve the above-mentioned copolymer, and general ether solvents are acceptable, such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether, Diethylene glycol monoethyl ether, etc.

The above-mentioned copolymer, curing agent, and curing accelerator are used to form a coating solution, which is cured after heating to form an excellent anti-fog and anti-frost coating with a certain bonding strength, and the coating can also produce good antistatic effect.

The hydrophilic macromolecular material of the present invention can also be (meth)acrylic acid ester monomer I and

(Meth)acrylic acid or, and hydroxyl-containing (meth)acrylate monomer II and N-vinylpyrrolidone III copolymer.

The present invention can also be above-mentioned monomer I, II and hydrophilic monomer IV copolymer, the structure of hydrophilic monomer IV is as follows:

(IV)

R ¹ is a hydrogen atom or a methyl group

R ⁴ is an amino group, or a hydrocarbon group with one to four carbons containing an amino group

The addition of hydrophilic monomer IV such as (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylate or the like can increase the anti-fog and anti-frost life.

The present invention can also be the copolymer of above-mentioned monomer II, III and (meth)acrylate monomer V, (meth)acrylate monomer such as: (meth)acrylic acid formic acid, (meth)acrylate ethyl ester, Butyl (meth)acrylate, etc., can choose any one or a combination of several. The addition of monomer V can increase the adhesion of the paint. The structure of (meth)acrylate monomer V is as follows:

R ¹ is a hydrogen atom or a methyl group

R ⁵ is an alkyl group of one to four carbons.

The hydrophilic polymer material is a quaternary combination of monomer II and any three monomers of monomers I, III, IV, and V, namely: I+II+III+IV, II+III+IV+V, etc.

Among the present invention, the (meth)acrylic acid ester of nonionic surfactant is ω--hydroxyl terminal nonionic surfactant, such as ω-hydroxyl terminal dodecanol ethoxyl group (n=4) methacrylate wait.

The above-mentioned nonionic surfactant (meth)acrylate is preferably ω-hydroxyl-terminated dodecyl alcohol ethoxy (n=4) methacrylate.

(Meth)acrylic acid or, and hydroxyl-containing (meth)acrylate II monomers, such as: acrylic acid, (2-hydroxyethyl) methacrylate, (3-hydroxypropyl) acrylate, etc. Acrylic acid or the combination of acrylic acid and hydroxyl-containing acrylate is preferred.

The curing agent is melamine and etherified derivatives, such as tributoxymethyl melamine, etc., preferably tributoxy melamine.

The curing accelerator is an acid or a salt of an acid, such as p-toluenesulfonic acid, etc., preferably p-toluenesulfonic acid.

The preparation method of hydrophilic polymer material is as follows:

In a reaction vessel equipped with a stirrer thermometer, put in solvent and comonomer, the weight ratio of monomer to solvent is 1: (2-5), under nitrogen, add monomer amount of 0.1 to 3.0wt% free radical polymerization Initiator, polymerize at 60-80°C for 6-10 hours, cool for later use. Add the curing agent and the curing accelerator etc. of the present invention component amount when using, promptly become the anti-fog coating of the present invention. The addition amount of various monomers is:

I: 20～80wt%

II: 20～80wt%

III: 20-80wt%

When the copolymerization mode of the present invention is I+II+III, the addition amount of various monomers is:

I: 10～80wt%

II: 10～80wt%

III: 10 to 80 wt%.

If the copolymerization mode of the present invention is I+II+IV (or V), during II+III+IV (or V), the addition of various monomers is:

I: 10-80wt%;

II: 10-80wt%;

III: 10-80 wt%.

IV: 10-20wt%;

V: 10-20wt%.

According to the content of the present invention, the copolymerization mode of the above-mentioned monomers is: I+II, II+III, I+II+III, I+II+IV (or V), II+III+IV (or V).

The addition amount of the above-mentioned initiator is more preferably 0.1-0.5 wt%. The initiator is an initiator used in the prior art, such as: ketone peroxide, diacyl peroxide, azo compound, hydroperoxide, peracid alkyl ester, etc.

The preparation of the monomer ω--hydroxyl-terminated nonionic surfactant (meth)acrylate is obtained by esterifying the omega--hydroxyl-terminated nonionic surfactant with an acrylic derivative of equal molar weight. This reaction is prior art.

The anti-fog and anti-frost composition of the present invention can be coated on a transparent substrate as a base, such as synthetic resin or glass, and dried with hot air to remove the solvent and cure the coating. The matrix of the resin is for example polymethacrylate, polycarbonate, polyethylene terephthalate, polystyrene and the like.

Place the coated glass and plastic products in an oven and heat at 50-120°C for 30-180 minutes to cure the coating, and adjust the curing conditions within the above range according to the end use and characteristics of the glass and plastic products.

The method of coating can be brushing, spraying or dipping according to the shape of the substrate to be coated.

The thickness of the coating is preferably 1-30 μm.

Preferred solvent in the composition of the present invention is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, adjusts the viscosity of composition at 25 ℃ with solvent at about 100cps (centipoise), so that coating has satisfactory surface characteristics . If the viscosity of the anti-fog coating used is too high, the disadvantages shown are wrinkling or fish eyes on the coating surface.

The anti-fog principle of the present invention is to use the resin coating to form a highly hydrophilic surface, so that the contact angle to water becomes smaller, and spreads on the surface as an extremely thin water film without forming tiny water droplets, so as to prevent diffuse radiation to achieve anti-fogging. fog effect.

The coating film of the present invention is tested as follows:

Coating film adhesion test, according to the national standard GB1720-79 of the People's Republic of China National Standard GB1720-79 Coating Film Adhesion Determination Relevant Items Determination of coating film adhesion. It is expressed in grades according to the evaluation of the completeness of the coating film within the scope of the rolling scratches.

Coating film water resistance test, water immersion test method. Immerse the sample coated with anti-fog coating in distilled water at a temperature of 40C, take it out after soaking for 240 hours, and dry it with filter paper. If the coating film peels off and wrinkles, it is unqualified.

Anti-fog performance: After placing a sample coated with anti-fog coating above 80C water vapor for 10 seconds, observe the fogging of the coating with naked eyes.

The above-mentioned test results all meet the existing standards, and some indicators exceed the existing standards, which fully demonstrates that the coating of the present invention has the characteristics of convenient preparation, low cost, long service life, and excellent anti-fog and anti-frost performance.

Detailed ways

Example 1

In 120g ethylene glycol monomethyl ether, add 18g omega-hydroxyl terminal dodecyl alcohol ethoxyl group (n=4) methacrylate, 6g methacrylate (2-hydroxyethyl) ester, 6g methacrylic acid and 0.15g of benzoyl peroxide, stir to dissolve completely, polymerize at 60C for 6 hours. After cooling, add 4.5g of tributoxymethyl melamine, 0.3g of p-toluenesulfonic acid and 0.6g of leveling agent, stir well and set aside.

Add 0.3g of p-toluenesulfonic acid to the above coating and mix well. The coating composition was sprayed onto the surface of the polycarbonate plate, pre-baked in an oven at 50°C for 0.5 hour, and then cured at 120°C for 1 hour to cure the coating.

Example 2-Example 6 uses example 1 method, different composition, component, obtained the anti-fogging coating of good performance, see the table below.

1 2 3 4 5 6 7 Composition of coating solution Copolymer Composition ω-HDEMAHEMANVPMAAAAMMAMEBPO 186 12 12 3 96 6 9 9 9918 12 9 15 663 333 3120 120 120 120 1200.15 0.15 0.15 0.15 0.15 0.15 BMCN leveling agent TPS 4.5 4.5 4.5 4.5 4.5 4.5 4.50.6 0.6 0.6 0.6 0.6 0.6 0.60.3 0.3 0.3 0.3 0.3 0.3 nature Transparency Adhesion Water Resistance Anti-Fog Effect Good, good, good, good, good, good, good, good, good, level 3 level 2 level 1 level 1 level 1 1 <240H <240H> 240H> 240H <240H <240H> 240H> 10S ＞ 10S ＞ 10S ＞ 10S ＞ 10S ＞ 10S

The abbreviated names in the table are as follows:

ω-HDEMA: ω-Hydroxy-terminated dodecyl alcohol ethoxy (n=4) methacrylate

NVP: N-Vinylpyrrolidone

HEMA: (2-Hydroxyethyl) methacrylate

MAA: methacrylic acid

AA: Acrylamide

MMA: methyl (meth)acrylate

ME: Ethylene glycol monomethyl ether

BPO: Benzoyl Peroxide

BMCN: Tributoxymethylmelamine

TPS: p-toluenesulfonic acid

Leveling agent: acrylate copolymer

Claims (15)

1. hydrophilic macromolecule anti-fog coating by hydrophilic macromolecule, solidifying agent, curing catalyst, solvent composition, is characterized in that their component is:

Hydrophilic high molecular material: 15～60wt%;

Solidifying agent: 2.0～20w

Curing catalyst: 0.1～5.0wt%;

Solvent: 30～80wt%;

Above-mentioned hydrophilic high molecular material is: the acrylate of ω-terminal hydroxy group nonionogenic tenside or methyl acrylic ester monomer (I) and (methyl) vinylformic acid or, with the acrylate of hydroxyl or the multipolymer of methacrylic ester (II), I, the structural formula of II is as follows:

(I)

R ²＝ ^*_CH ₂-GH ₂-O_ m＝1～40

R″＝-C _nH _2n+1 n＝8～18

Or R=-C _n' H _{2n '+1}N '=1～22

R ¹Be hydrogen atom or methyl;

R ³For hydrogen atom or hydroxyl contain a alkyl to four carbon.

2. hydrophilic macromolecule anti-fog coating according to claim 1 is characterized in that hydrophilic high molecular material is monomer (I) and the multipolymer of monomer (II) with N-vinyl pyrrolidone (III), and the structural formula of III is as follows:

(III)

3. hydrophilic macromolecule anti-fog coating according to claim 1 is characterized in that hydrophilic high molecular material is the multipolymer of monomer I, II and hydrophilic monomer (IV), and the structure of hydrophilic monomer (IV) is as follows:

(IV)

R ¹Be hydrogen atom or methyl;

R ⁴For amino or contain an amino alkyl to four carbon.

4. hydrophilic macromolecule anti-fog coating according to claim 1, it is characterized in that hydrophilic high molecular material is the multipolymer of monomer I, II and acrylate or methacrylate monomer (V), the structure of acrylate or methacrylate monomer (V) is as follows:

R ¹Be hydrogen atom or methyl;

R ⁵It is a alkyl to four carbon.

5. according to claim 1 or 2 or 3 or 4 described hydrophilic macromolecule anti-fog coatings, it is characterized in that (methyl) vinylformic acid or and the acrylate of hydroxyl or the acrylate that methacrylate monomer (II) is vinylformic acid or vinylformic acid and hydroxyl share.

6. hydrophilic macromolecule anti-fog coating according to claim 5 is characterized in that the acrylate of ω one terminal hydroxy group nonionogenic tenside or methacrylic ester are ω one terminal hydroxy group dodecanol oxyethyl group n=4 methacrylic esters.

7. hydrophilic macromolecule anti-fog coating according to claim 1 is characterized in that solidifying agent is trimeric cyanamide and etherification derivative.

8. hydrophilic macromolecule anti-fog coating according to claim 1 is characterized in that curing catalyst is acid or sour salt.

9. hydrophilic macromolecule anti-fog coating according to claim 2, the preparation method who it is characterized in that hydrophilic high molecular material in this anti-fog coating is in thermometric reactor is arranged, drop into monomer and solvent, drop into monomeric logical simultaneously nitrogen, and adding radical initiator, under the 60-80 ℃ of temperature polymerization 6-10 hour, cooling got final product; The weight ratio of monomer and solvent is 1: (2-5), the add-on of initiator is the 0.1-3.0wt% of amount of monomer, and various monomeric add-ons are as follows:

I：20-80wt％；

II：20-80wt％；

III:20-80wt%; Each monomer add-on sum is 100%.

10. hydrophilic macromolecule anti-fog coating according to claim 2 is characterized in that various monomeric add-ons are as follows:

I：10-80wt％；

II：10-80wt％；

III:10-80wt%; Each monomer add-on sum is 100%.

11. hydrophilic macromolecule anti-fog coating according to claim 6 is characterized in that the ω-terminal hydroxy group nonionogenic tenside monomer of gram molecular weights such as the ω-acrylate of terminal hydroxy group nonionogenic tenside or the preparation method of methacrylic ester are and acrylic acid derivative esterification obtain.

12. hydrophilic macromolecule anti-fog coating according to claim 1, the solvent that it is characterized in that this coating are ethylene glycol monomethyl ether or ethylene glycol monoethyl ether.

13., it is characterized in that this coating is to be coated on the transparent substrate after the drying when using according to the using method of claim 1 hydrophilic macromolecule anti-fog coating, be positioned over 50-120 ℃ of heating 30-180 minute down, coating curing is got final product.

14. the using method of hydrophilic macromolecule anti-fog coating according to claim 1, the coating method that it is characterized in that this coating are brushings, or spraying, or dip-coating.

15. the using method of hydrophilic macromolecule anti-fog coating according to claim 1 is characterized in that the thickness that anti-fog coating is coated on the residuite is 1-30um.