JPH01247448A - Fluorinated copolymer composition - Google Patents

Abstract

PURPOSE:To improve the surface gloss and ultraviolet absorptivity of the obtained coating film, by mixing a specified fluorinated copolymer with, optionally, a curing agent. CONSTITUTION:A fluorinated copolymer having an intrinsic viscosity (in tetrahydrofuran at 30 deg.C) of 0.05-2.0dl/g, a content of fluorine atoms originating in a fluoroolefin >=10wt.%, a content of units derived from an alkyl vinyl ether or an alkyl vinyl ester of 70-30mol% and ultraviolet absorptivity is optionally mixed with a curing agent such as a polyisocyanate, aminoplast, polybasic acid anhydride, metal alkoxide or polyamine compound curing agent, a solvent, a synthetic resin, a curing catalyst, a heat stabilizer, a leveling agent, etc.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a fluorine-containing copolymer composition.

[Prior art] Conventionally, fluororesin paints whose main component is a solvent-soluble fluorine-containing copolymer have much better weather resistance than other general-purpose paints. It is widely used in various fields such as fiber, glass, and cement. Paint films based on fluororesin paints have excellent weather resistance and are extremely resistant to deterioration due to ultraviolet rays, etc., but when a clear film is applied to #,
There was a problem in that the base material deteriorated because ultraviolet rays were transmitted through it.

In order to solve this problem, a method has been implemented in which an ultraviolet absorber is added to the fluororesin paint. Further, for the purpose of reducing the amount of loss of the ultraviolet absorber that occurs during coating film baking, a set IA product containing a special ultraviolet absorber is also found in JP-A-60-3δCo-55. In addition, fluorine-containing copolymers having a group having an ultraviolet absorbing source are also
1:1229.

[Problems to be solved by the invention] Conventional fluorine-81 paints containing special ultraviolet absorbers are
During drying, some of the UV absorber is distilled off as the solvent evaporates, and 100% of the added UV absorber is not utilized.
In addition, there was a problem that unreacted ultraviolet absorber may bleed out.

Further, the fluorine-containing copolymer having an ultraviolet absorbing group is limited in the solvents in which it can be dissolved, for example, it is insoluble in nonpolar solvents. It had problems such as the paint film being difficult to get glossy.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems, and the present invention has been made to solve the above-mentioned problems. It has 70 to 30 mol% of
Contains a group with ultraviolet absorbing ability and has an intrinsic viscosity of 0.05 to 2.0 dl measured in tetrahydrofuran at 30°C
/ g of a fluorine-containing copolymer composition.

The composition of the present invention has a fluorine content of 10% by weight or more based on fluoroolefins, and contains 70 to 70% of units based on alkyl vinyl ether or alkyl vinyl ester.
It contains 30 mol% and has a group having ultraviolet absorbing ability (hereinafter referred to as UVAC), and has a 30°C content in tetrahydrofuran.
Intrinsic viscosity measured at C is 0.05-2.0 dl/g
Contains a fluorine-containing copolymer. In such a fluorine-containing copolymer, examples of the fluoroolefin include vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, pentafluoropropylene, and hexafluoropropylene. In particular, fluoroolefins having about 2 to 4 carbon atoms are preferred.

Further, as the alkyl vinyl ether or alkyl vinyl ester, a vinyl ether or vinyl ester having an alkyl group having about 1 to 15 carbon atoms is employed. Such alkyl groups may be straight, branched, or alicyclic. Examples of such alkyl vinyl ethers include ethyl vinyl ether, propyl vinyl ether, n-butyl vinyl ether, ter-butyl vinyl ether, hexyl vinyl ether, cyclohexyl vinyl ether, and octyl vinyl ether. Further, as the alkyl vinyl ester, ethyl vinyl ester, n-butyl vinyl ester, ter-
Examples include butyl vinyl ester, hexyl vinyl ester, octyl vinyl ester, and decyl vinyl ester. Various types of UVAC can be employed, but those having a basic structure of benzophenone, benzotriazole, or phenyl salicylate are preferred because they are easy to manufacture and have excellent ultraviolet absorption. Such 0VA(: may be included in the main chain of the fluorine-containing copolymer, or it is difficult to substantially introduce main chain IJVAc, and uvAc is usually introduced into the side chain. Introducing methods include epoxy groups,
UVAC is produced by reacting a reactive ultraviolet absorber with a vinyl intermediate having a reactive group such as an active hydrogen-containing group such as a hydroxyl group or a carboxylic acid group, or by bonding the ultraviolet absorber with a coupling agent. A method of copolymerizing a vinyl monomer with a fluoroolefin and an alkyl vinyl ether or an alkyl vinyl ester, There are methods such as reacting a reactive ultraviolet absorber with a polymer or binding the ultraviolet absorber using a linking agent. Here, the linking agent is a polyfunctional compound having a group that reacts with both the reactive group of the vinyl monomer or the fluorine-containing copolymer and the reactive group of the ultraviolet absorber. For example, if a vinyl monomer or a fluorine-containing copolymer has a hydroxyl group, and a UV absorber also has a hydroxyl group, it is difficult to react them directly, but compounds such as diisocyanates and polyhydric carboxylic acids can be used. By reacting, both can be easily combined.

The linking agent is a compound that acts in the same way as diisocyanate, polycarboxylic acid, etc. in this case.

Examples of reactive ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy4-(2-hydroxyethoxy)benzophenone, and 2-hydroxy-4-(2-hydroxybenzophenone).
-hydroxypropoxy)benzophenone, 2-(2°
-Hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-
5-chlorobenzotriazole, 4-carboxylic phenyl salicylate, 2-hydroxy-4-(2'-
Examples include ethyl succinate) benzophenone and 2-(2'-hydroxy-3'-aminomethyl) benzotriazole.

In the present invention, the fluorine-containing copolymer has a fluorine content of 10 parts [11% or more] based on the fluoroolefin. If the fluorine content is too low, good weather resistance is not achieved and is not preferred;
Contains ~70 mol%. If the proportion of units based on alkyl vinyl ether or alkyl vinyl ester is less than the above ratio, the solubility in non-polar solvents will be extremely low, and gloss will not be obtained when formed into a coating, which is undesirable. Weather resistance decreases, which is undesirable.
The Iil of UVAC is determined as appropriate depending on the purpose, but usually the polymerized unit containing υVAC is 0 relative to the total polymerized units.
．． Those containing 5 mol% or more are preferably employed. If the amount of UVAC is too small, a sufficient ultraviolet shielding effect cannot be achieved, and if it is too large, the solubility in solvents will decrease and the physical properties of the coating film will deteriorate, which is undesirable. It is less than mol%. When UVAC is introduced into the reactive groups of the fluorine-containing copolymer, if the reactive groups are the same as the curing reaction sites described below, 0VA (: may be introduced into all of the reactive groups. In order to ensure the curability of the fluorine copolymer, it is preferable to leave reactive groups.

The remaining amount is preferably 50% or more of the total reactive groups.

In the present invention, the fluorine-containing copolymer may be one in which a copolymerizable monomer is copolymerized in addition to the above three types of components. , allyl compounds, acryloyl compounds, methacryloyl compounds, olefins, fluorine-containing vinyl compounds, and the like. Moreover, it is preferable that the fluorine-containing copolymer has a curing reactive site.

Such curing reactive sites include active hydrogen-containing groups such as hydroxyl groups, carboxylic acid groups, acid amide groups, amino groups and mercapto groups, epoxy groups, unsaturated groups, active halogen-containing groups such as iodine and bromine, hydrolyzable silyl groups, etc. Examples include groups. Among these, active hydrogen-containing groups or epoxy groups are preferably employed because of their excellent reactivity with the curing agent described below.

Methods for introducing such a curing-reactive site include copolymerizing a 7mer having a curing-reactive site, converting a part of the fluorine-containing copolymer into a curing-reactive site, and causing the fluorine-containing copolymer to undergo a curing reaction. Examples of methods include reacting a compound that has a reactive site or provides a curing reactive site. Here, examples of the polymer having a curing reactive site include hydroxyalkyl vinyl ether, hydroxyalkyl allyl ether, hydroxyalkyl vinyl ester, hydroxyalkyl allyl ester, glycidyl vinyl ether, chrycidyl allyl ether, aminoalkyl vinyl ether, aminoalkyl allyl ether , aminoalkyl vinyl ester, aminoalkyl allyl ether, acrylic acid, methacrylic acid, allyl vinyl ether, and the like.

A method for converting a part of a fluorine-containing copolymer into a curing reactive site is to copolymerize a hexamer having an ester bond that can be hydrolyzed after polymerization, and then hydrolyze it to form a carboxylic acid group or There is a method of converting it into a hydroxyl group. In addition, methods for introducing a curing site by reacting a compound into a fluorine-containing copolymer include a method in which a polyhydric carboxylic acid anhydride is reacted with a fluorine-containing copolymer having a hydroxyl group to introduce a carboxylic acid group; A method of introducing an unsaturated group into a fluorine-containing copolymer having an epoxy group by reacting an isocyanate group-containing acryloyl compound or methacryloyl compound or a compound such as acrylic acid chloride; Examples include a method of reacting a carboxylic acid anhydride to introduce a hydroxyl group and a carboxylic acid group, and a method of reacting a phenol to introduce a hydroxyl group.

The fluorine-containing copolymer in the present invention has an intrinsic viscosity of 0.05 to 2.0 as measured at 30°C in tetrahydrofuran.
dl/g. If the intrinsic viscosity is too small,
It is not preferable because the physical properties of the coating film cannot be sufficiently obtained, and the coating film thickness cannot be obtained sufficiently.

Further, a material having an excessively high intrinsic viscosity is not preferable because it reduces workability.

It is preferable that the composition of the present invention contains a curing agent in addition to the fluorine-containing copolymer because a tough coating film with excellent solvent resistance can be obtained. As such a curing agent, a compound that acts on a group capable of reacting with the curing reactive site of the fluorine-containing copolymer and reacts with the fluorine-containing copolymer to give a good cured product is employed. . Examples of such curing agents include polyisocyanates, aminoplasts, polybasic acid anhydride metal alkoxides, and polyvalent amine compounds. Polyisocyanate compounds include polyisocyanate compounds such as hexamethylene diisocyanate, silyl isocyanate compounds such as methylsilyl triisocyanate, partial condensates and polymers of these, and isocyanate groups with blocks such as phenol. Examples include blocked polyisocyanate compounds blocked with a curing agent.

In particular, a non-yellowing type is preferably employed. As the aminoblast, melamine resin, guanamine resin, urea resin, etc. are used.

Among them, melamine that has been at least partially etherified with one or more lower alcohols such as methanol, ethanol, propatool, and butanol is preferably employed. Examples of polybasic acid anhydrides include aromatic polycarboxylic acid anhydrides such as phthalic anhydride and pyromellitic anhydride, and aliphatic polycarboxylic acid anhydrides such as maleic anhydride and succinic anhydride.

In addition to the above-mentioned components, the composition of the present invention may contain various additives as necessary. Examples of such additives include a solvent, a synthetic resin, a curing catalyst, a heat stabilizer, a leveling agent, and a lubricant. , pigments, dyes, viscosity modifiers, dispersion stabilizers, anti-gelling agents, etc. In particular, when used for coating such as paint, each component is preferably dispersed or dissolved in an appropriate solvent. As such solvents, both polar and non-polar solvents can be used, including aromatic hydrocarbons such as xylene and toluene, alcohols such as n-butanol, esters such as butyl acetate, ketones such as methyl isobutyl ketone, In addition to glycol ethers such as ethyl cellosolve, various thinners for reprinting can also be employed, and these can also be used by mixing them in various proportions. Further, as the synthetic resin, acrylic resin, phenol resin, epoxy resin, polyimide resin, polyamide resin, polyether resin, silicone resin, etc., and elastomer materials such as polyurethane and acrylic elastomer are used. Moreover, these precursors may be blended. Preferably, it has a group similar to or capable of reacting with the curing reactive site of the fluorine-containing copolymer.

[Examples] The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples in any way.

Synthesis Example 1 Tetrafluoroethylene, ethyl vinyl ether, and glycidyl vinyl ether were 50.40 and 10.0, respectively. Fluorine-containing copolymer 10 (1 part by weight, 50 parts by weight of xylene, 50 parts by weight of methyl isobutyl ketone, 3 parts by weight of 2,4-dihydroxybenzophenone)
6 parts by weight and 1 part by weight of triphenylphosphine were added and the reaction was carried out at 120°C for 6 hours to obtain UVAC fluorine-containing copolymer A-1. The intrinsic viscosity of this fluorine-containing copolymer measured in tetrahydrofuran at 30°C is 0.
It was 22 dl/g.

Synthesis Examples 2 to 8 A fluorine-containing copolymer having #, (mol%) in the copolymer set shown in Table 1 was reacted with 2,4-dihydroxybenzophenone in the same manner as in Synthesis Example 1 to produce UVAC. Fluorine-containing copolymers A-2 to A-8 were obtained.

Table 1 Binino μ Stell Note that in Table 1, the numbers for the fluorine-containing copolymer composition are mol%.
It is.

Synthesis Example 9 5 units each based on tetrafluoroethylene, ethyl vinyl ether, and hydroxybutyl vinyl ether
Fluorine-containing copolymer 1 contained at 0.30.20 mol%
00 parts by weight, 100 parts by weight of xylene 2-(2'-
Hydroxy-3',5'-di-t-butylquenyl)-
Add 1 part by weight of 5-chlorobenzotriazole and react at 140°C for 7 hours to form an IJV
A fluorine-containing copolymer A-9 having AC was obtained. The intrinsic viscosity of this fluorine-containing copolymer measured in tetrahydrofuran at 30°C was 0.16 dl/g.

Synthesis Example 10 46 parts by weight of glycidyl vinyl ether and 2.4-
A vinyl monomer having UVAC was obtained by reacting 214 parts by weight of dihydroxybenzophenone in xylene in the presence of triphenylphosphine at 120°C for 5 hours.

In the autoclave, in the presence of methyl isobutyl ketone,
Chlorotrifluoroethylene, hydroxybutyl vinyl ether, cyclohexyl vinyl ether, and the above vinyl monomer having UVAC were each mixed with 40,
15. : 15.10 mol was charged, and polymerization was carried out at 70° C. for 10 hours in the presence of azoisobutyronitrile to obtain a fluorine-containing copolymer A-10 having UVAC. The intrinsic viscosity of this fluorine-containing copolymer measured in tetrahydrofuran at 30°C was 0.2: ldl/g.

Examples 1 to 9 Comparative Example 1 The solubility of the UVAC-containing fluorine-containing copolymers A-1 to A-10 obtained in Synthesis Examples 1 to 10 above in xylene and methyl ethyl ketone (○, - part dissolved) △
, insoluble was marked as x) and 100 parts by weight of the fluorine-containing copolymer having each IJVAC, Tsurpets 1501
00 parts by weight, 25 parts of cyclohexanone, Evomate B-002 (hardening agent for epoxy manufactured by Yuka Shell Co., Ltd.) 10
The paint containing the parts by weight was applied to a film thickness of 25 tiles on a glass plate and cured at 200°C for 80 seconds to obtain a test piece.

The surface gloss of this test piece, the absorption rate of light with a wavelength of 350 mm,
Table 2 shows the surface condition after 250 hours of duty cycle and the absorption rate of light at a wavelength of 350 cm.

Comparative Example 2 Fluorine-containing copolymer A-11 100 parts by weight, in which chlorotrifluoroethylene, cyclohexyl vinyl ether, ethyl vinyl ether, and glycidyl vinyl ether were copolymerized in proportions of 50, 15, 15° and 20 mol%, respectively,
Tsurpez 150 100 parts by weight, cyclohexanone, 2
A paint containing 5 parts by weight, Coronate 2507 (manufactured by Nippon Polyurethane Co., Ltd.; blocked isocyaner), 1s part by weight, 0.03 parts by weight of dibutyltin dilaure), and 20 parts by weight of 2,4-dihydroxybenzophenone was applied on a glass plate. It was applied to a film thickness of 25 μl and cured at 200° C. for 60 seconds to obtain a test piece. The surface gloss of this specimen, (
60℃ gloss), absorption rate of light at wavelength 350cm.

Surface condition after due cycle/250 hours, wavelength 350
Table 2 shows the light absorption rate of III11.

The surface conditions in Table 2 are those with no change and those with O1 whitening etc.
.

Severe cases such as bleaching were marked with an X.

[Effects of the Invention] The composition of the present invention is soluble in various solvents and provides a coating film with excellent surface gloss and excellent ultraviolet absorption properties, so it can be used in various protective coatings, especially outdoor synthetic resins. Extremely useful as a coating paint. Furthermore, by forming a cured coating film using a curing agent, a coating film with even better solvent resistance can be obtained, and the surface of the coating film can also be cleaned using a solvent.

Claims (1)

[Claims] 1.The fluorine content based on the fluoroolefin is 10% by weight or more, has 70 to 30 mol% of units based on alkyl vinyl ether or alkyl vinyl ester, has a group having ultraviolet absorbing ability, and is heated at 30°C in tetrahydrofuran. Measured intrinsic viscosity is 0.05 to 2.0 dl
/g of a fluorine-containing copolymer composition.