JPH04110309A - Curable fluorine-containing copolymer and composition containing the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a curable fluorine-containing copolymer.

[Prior Art] The present applicant has discovered that fluoroolefins, cyclohexyl vinyl ethers, alkyl vinyl ethers, and hydroxyalkyl vinyl ether copolymers are cured with curing agents such as melamine and isocyanates, as shown in Japanese Patent Application Laid-Open No. 57-34107. It has already been found that curing is possible at room temperature and baking and provides a weather-resistant coating film with high gloss and excellent weather resistance. However, if the above copolymers are to be widely applied as solution-type paints, if a large amount of hydroxyalkyl vinyl ether is introduced in order to add hydroxyl groups, which are curing sites, the affinity for non-polar solvents will decrease, and the solution-type paints will However, the problem was that its adaptability as a device was restricted.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems.
It contains ~60.25~55.5~25.2~30 mol% and has an intrinsic viscosity of 0.2% as measured at 30°C in tetrahydrofuran. A curable fluorine-containing copolymer having an O of 1 to 2.0 dl/g.

a) (CF2-CFX) X is fluorine, chlorine, or a perfluoroalkyl or perfluoroalkoxy group having 1 to 3 carbon atoms.

b) -CH2-CR'- O-(C)l-R2 R' is hydrogen or methyl group, R' is unsubstituted or fluorine-substituted linear, branched or alicyclic alkyl having 1 to 12 carbon atoms group, 1 is O or 1°R3 is hydrogen or a methyl group, R4 is an unsubstituted or fluorine-substituted linear, branched or alicyclic alkyl group having a hydroxyl group.

d) -CF2'-CF- (m=2-9, n=O-2, p=1-2).

That is, by introducing an appropriate amount of polyfluorovinyl ether having a hydroxyl group, it is possible to increase the hydroxyl value while maintaining the amount of fluoroolefin within a range that does not reduce weather resistance, and likewise maintain solubility in non-polar solvents. Is possible.

The fluorine-containing copolymer of the present invention has formulas a) and b).

It is composed of polymerized units represented by c) and d').

a) (CFa-C:FX) X is fluorine, chlorine, or a perfluoroalkyl or perfluoroalkoxy group having 1 to 3 carbon atoms.

R+ is hydrogen or a methyl group, R2 is an unsubstituted or fluorine-substituted linear, branched or alicyclic alkyl group having 1 to 12 carbon atoms, l is O or 1°, R3 is hydrogen or a methyl group, R4 is a hydroxyl group An unsubstituted or fluorine-substituted linear, branched or alicyclic alkyl group having

d) -CF, -CF- (m=2-9, n=-0-2, p=1-2) Each polymerized unit has the formula a'L b'), c').

By copolymerizing the monomer represented by d'),
can be formed.

a') CF2”CFX: X is the same as above:
R', R2, 1 are the same as above d') CF2=CFO(CF2), (OCF2CF
2) □ (CH2), OH: m, n, p are the same as above, where the monomer represented by formula a') is tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, perfluoromethyl Examples include vinyl ether. Monomers represented by formula 1)') include ethyl vinyl ether, n-butyl vinyl ether, cyclohexyl vinyl ether, ethyl isopropenyl ether, n-butyl isopropenyl ether,
2.2.3.3 Vinyl ethers such as fluoropropyl vinyl ether, vinyl acetate, isopropenyl acetate, vinyl n-butyrate, isopropenyl n-butyrate, vinyl valerate, vinyl isovalerate, vinyl bivalate, Vinyl esters such as vinyl laurate are exemplified. Examples of the monomer represented by formula c') include ω-hydroxybutyl vinyl ether, ω-hydroxyethyl vinyl ether, ω-hydroxybutyl isoprobenyl ether, and monovinyl ether of cyclohexane dimetatool.

Furthermore, as the monomer represented by d), 3-oxa-
],, ],, 2.4.4.5.5.6.6-Nonafluorophyloxy 1-heptene, 3-oxa-
1, 1, 2, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8
-1□Lidecafluoro 9-hi 1 to waxy 1-nonene, 3,7-thioxer 1. l, 2.4.4.5.5
．． 6.6.8.9.9-dogakafluoro8-trifluoromedyl-10-hydroxy-1-decene, 3-oxa-1,l, 2.4.4.5.5.6.6-nonafluoro-8 -Hydroxy-1-octene and the like are exemplified.

Furthermore, the polymerized units represented by a), l:l), c), and d) may each be a single unit, or may be in the form of a mixture of two or more types.

The fluorine-containing copolymer of the present invention has the above formula a).

The polymerized units represented by b), c), and d) are each 3
0 to 60 mol%, 25 to 55 mol%, 5 to 25 mol%,
It is 2-30%. Too low amounts of polymerized units represented by formulas a) and (1) are unfavorable from the viewpoint of weather resistance.

Furthermore, polymer units represented by formulas a) and d) with too low l or too high l are difficult to manufacture.

If the number of polymerized units represented by formula b) is too high, it is unfavorable from the viewpoint of weather resistance, and if it is too low, the solubility in solvents decreases, making it unsuitable as a solution-type paint base. In addition, it is important that the polymerized units represented by formula C) be contained in a proportion within the above range so as not to impair various useful properties as a paint base (especially important from the perspective of improving curability). In other words, if the content of polymerized units represented by formula C) is too high, the solubility of the copolymer changes and it becomes soluble only in specific substances such as alcohols, making it difficult to use as a solution-made paint base. Not only does it limit the adaptability, but it also reduces the fragility of the cured paint film and reduces the gelation time (bot life) in the presence of a hardening agent, significantly impairing the workability of the paint. In addition, if the content is too low, the effect of improving curability is lost, resulting in an increase in curing time and a decrease in solvent resistance, stain resistance, etc. of the cured oil film, and further, This is undesirable because it causes disadvantages such as profiteering and loss of adhesion with the brimer.

The copolymer of the present invention has an intrinsic viscosity of 001 to 2.0 d measured in tetrahy]herofuran at 30°C in an uncured state.
1. It is important that the amount is 0.02 to 1.0 dl/g, preferably 0.02 to 1.0 dl/g. If the viscosity is too low, the mechanical strength will decrease, while if the viscosity is too high, when applied as a solution-type paint, the temperature of the hot liquid will have to be lowered due to the viscosity, resulting in poor workability. Both are undesirable because they cannot be damaged.

In the above-mentioned method for producing a fluorine-containing copolymer, a water-soluble or oil-soluble initiator can be used as the polymerization initiator, depending on the polymerization type or polymerization medium.

Specifically, the water-soluble initiator includes a redox initiator consisting of a persulfate such as potassium persulfate, hydrogen peroxide, or a combination of these with a reducing agent such as sodium bisulfite or sulfur thiosulfate; Furthermore, inorganic initiators such as systems in which small amounts of iron, ferrous salts, silver nitrate, etc. are coexisting, or dibasic acid peroxides such as disuccinic acid peroxide, diglutaric acid peroxide, monosuccinic acid peroxide, azo Organic initiators such as bisisobutyramidine dihydrochloride, and oil-soluble initiators such as t
-Peroxyester type peroxides such as butyl peroxyisobutyrate and t-butyl peroxyacetate, dialkyl peroxydicarbonates such as diisopropyl peroxydicarbonate, benzoisperoxide, azobisisobutyronitrile, etc. exemplified,
The amount of the polymerization initiator used can be changed as appropriate depending on the type, copolymerization reaction conditions, etc., but it is usually 0.005 to 5% by weight, especially 0.005 to 5% by weight, based on the monomer to be copolymerized. 005
About 0.5% by weight is adopted.

In the above copolymerization reaction, the reaction format is not particularly limited, and suspension polymerization, emulsion polymerization, solution polymerization, etc. can be adopted, but stability of the polymerization reaction operation, ease of classification of the produced copolymers, etc. Emulsion polymerization in an aqueous medium or solution polymerization using alcohols such as t-butanol, esters, aromatic compounds such as xylene, saturated herogenated hydrocarbons containing one or more fluorine atoms, etc. as a solvent, etc. is preferably adopted. In addition, when carrying out the copolymerization reaction in an aqueous medium, a basic buffer is added to reduce the pH of the liquid during matching.
It is preferred that the H value does not fall below 4, preferably 5. Addition of a basic substance is also effective in solution polymerization.

In this copolymerization reaction, the copolymerization reaction temperature is 0°C.
The optimum value can be appropriately selected within the range of ~+150°C depending on the type of polymerization initiator, polymerization medium, etc.; however, when carrying out the copolymerization reaction in an aqueous medium, the temperature is between 0°C and +100°C.
, preferably about 10°C to 90°C. In addition, the reaction pressure can be selected as appropriate, but is usually 1 to 10
It is desirable to adopt 0 kg/cm2, especially about 2 to 50 kg/cm2.

Furthermore, in order to suppress the intrinsic viscosity of the resulting copolymer within the above range, the copolymerization reaction may be carried out in the presence of an appropriate chain transfer agent.

The copolymer of the present invention contains hydroxyl groups based on polymerized units represented by formulas C) and d) as curing sites, and contains melamine curing agents such as those used in ordinary thermosetting acrylic paints, and urea. It can be cured by heating using a resin curing agent, a polybasic acid curing agent, or the like. Examples of the melamine curing agent include butylated melamine, methylated melamine, epoxy-modified melamine, etc., and various degrees of modification from 0 to 6 can be used depending on the purpose, and the degree of self-condensation can also be selected as appropriate. . Examples of urea resin include methylated urea,
Examples include butylated urea. Further, as the polybasic acid curing agent, long-chain aliphatic dicarboxylic acids, aromatic polycarboxylic acids or their anhydrides, block polyvalent isocyanates, etc. are useful. When using melamine or urea hardeners, curing can be accelerated by adding an acidic catalyst.

The copolymer of the present invention can also be cured at room temperature using polyvalent isocyanates. As the polyvalent incyanate, non-yellowing diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate, and adducts thereof are particularly useful. When curing is carried out at room temperature using isocyanates, it is also possible to accelerate curing by adding a known catalyst such as dibutyltin dilaurate.

In making the copolymer of the present invention into a solution-type coating, various solvents can be used, including aromatic hydrocarbons such as xylene and toluene, alcohols such as n-butanol, esters such as butyl acetate, In addition to ketones such as methyl isobutyl ketone, glycol ethers such as ethyl cellosolve, and the like, various commercially available thinners can also be employed.

Mixing with such a copolymer can be carried out using various equipment commonly used for forming paints, such as a ball mill, a paint shaker, a sand mill, a jet mill, a three-roll mill, a kneader, and the like. At this time, pigments, branching stabilizers, viscosity modifiers, leveling agents, anti-gelling agents, ultraviolet absorbers, etc. can also be added.

When the copolymer of the present invention is used as a heat-curable so-called baking paint, melamine, urea resin,
A curing agent such as a polybasic acid or its anhydride or a blocked polyvalent isocyanate is also mixed at the same time and used as a -wave type paint.

On the other hand, in the case of using a cold-curing type compound using non-flocked polyvalent inocyanates, the curing agent components are prepared separately and a two-component type compound is used. In this case, by adjusting the type and amount of isocyaners 1 to 1 and the catalyst, as well as the copolymer concentration and the content based on C) and d) of the copolymer, it is possible to have time, several hours ~
A paint that cures at room temperature in a few days and provides a coating film with good physical properties can be obtained.

[Example] Example] Inside @v! A 260 cc stainless autoclave with a stirrer (pressure resistance 25 kg/cm2) was heated to 65 liters/ton.
9g, tert-butyl alcohol 186g, cyclohexyl vinyl ether (hereinafter abbreviated as CHV E)
165 g, ethyl vinyl ether (hereinafter abbreviated as EVE) 94 g, hydroxybutyl vinyl ether (hereinafter abbreviated as ) I B VE) 218 g, 3-oxa-1,], 2.4.4.5.5 .6.6-Nonafluorophyloxyl-heptene (CF2=CFO
(CF2) 3CH20H, hereinafter abbreviated as 0HFVE-1), 18 g of potassium carbonate, and 0.2 g of azobisisobutyronitrile (AIBN) were charged, solidified with liquid nitrogen, and dissolved air was removed by degassing.

However, chlorotrifluoroethylene (hereinafter referred to as c
40.6 g of F r (abbreviated as r F r) was introduced into an autoclave, and the temperature was gradually raised. in an autoclave)
When the crystallinity reaches 65℃, the pressure is 13.1kg/cm.
Indicates G.

Afterwards, the reaction was continued under stirring for 24 hours, at a pressure of -0.2k.
g/cm"G, cool the Autora 1 node with water to stop the reaction. After reaching room temperature, purge unreacted monomers and open the autoclave. Pour the resulting polymer solution into water. After precipitating the polymer, it is washed and dried to recover the polymer.The polymer yield is]
, 02.1 g, the polymer concentration was 53.3%, and the monomer reaction rate was 92.0%. Intrinsic viscosity of the obtained polymer (in tetrahydrofuran, 30'C) ([nm)
is 0. ], 8d1. /g. ' ``As a result of compositional analysis by C-nmr, CTFE/CHVE/HVE/HBV
E1011FV [-1= 39.5/1.5.0/16
．． I]/1.9.0/1.0.5.

Further, the hydroxyl value of the polymer was 130.

When 5 g of Suwasol 310 manufactured by Maruzen Petrochemical Co., Ltd. was added to 10 g of polymer and dissolved, a transparent solution was obtained.

Comparative Example 1 A polymer with a hydroxyl value of 3D was synthesized in the same manner as in Example without adding OHF V E-1. The composition ratio of the obtained polymer is G T F E / C H V I
E / E ~ l E / HB VE =51.0/
It was 1.5.0/7.21/26.8.

When a solubility test similar to Example] was carried out, the solution became slightly cloudy.

Example 2 Polymerization was carried out under the same conditions as in Example 1. The conditions and results are shown in Table 1.

G Table 1 ii,] 0tIFVE-1; CF2=CFO(C
Fz)3CH20110HFVE-2; CF, =CF
OFCF,)5C)1201-10HFVE-3;CF
2=CFO(CF2)3fJ12CH20H*2 Evaluated by the same method as in Example 1 [Effects of the invention] The copolymer of the present invention is characterized by having high affinity for nonpolar solvents and maintaining a high hydroxyl value. It can be widely used as a base for solution-based paints. By introducing a monomer having an alcoholic hydroxyl group that is poorly soluble in water, the effect of improving latex stability during emulsion polymerization is expected.

The monomer component represented by formula d) has a high fluorine content, and the polymer is effective as a coating material having high water repellency.

Claims (1)

[Scope of Claims] 1) Contains 30 to 60, 25 to 55, 5 to 25, and 2 to 30 mol% of monomer units represented by the following formulas a) to d), respectively, and is measured at 30°C in tetrahydrofuran. A curable fluorine-containing copolymer having an intrinsic viscosity of 0.01 to 2.0 dl/g. a) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ X is fluorine, chlorine, or perfluoroalkyl or perfluoroalkoxy group having 1 to 3 carbon atoms. b) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ R^1 is hydrogen or a methyl group, R^2 is an unsubstituted or fluorine-substituted linear, branched, or alicyclic alkyl group with 1 to 12 carbon atoms, l is 0 or 1. c) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ R^3 is hydrogen or a methyl group, and R^4 is an unsubstituted or fluorine-substituted linear, branched, or alicyclic alkyl group having a hydroxyl group. d) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (m=2-9, n=0-2, p=1-2)