JPS62197468A - High-solid resin composition having excellent low-temperature curability - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which does not cause lowering in MW and has excellent low-temperature curability, consisting of a specified modified acrylic copolymer having (beta-methyl) glycidyl groups, a reactive oligomer and a redox polymn. catalyst. CONSTITUTION:100pts.wt. acrylic copolymer having (beta-methyl) glycidyl groups, composed of 5-25wt% (beta-methyl) glycidyl (meth)acrylate and 95-75wt% other polymerizable vinyl monomer (e.g., styrene) is reacted with 5-60wt% drying oil fatty acid having an iodine value of 100 to 200 (e.g., cottonseed oil) to obtain a modified acrylic copolymer (A) having (beta-methyl) glycidyl groups. 100pts.wt. in total of 50-90wt% component A and 50-10wt% reactive oligomer (B) having at least two unsaturated groups (e.g., 1,3,7-octatriene) is blended with a redox polymn. catalyst (C) consisting of 0.2-5pts.wt. org. peroxide and 0.001-0.1pt.wt. org. metal salt or 0.01-1.0pt.wt. tert. amine compd.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a high solid content resin with excellent low temperature curability, which contains a specific modified acrylic comonomer, a specific reactive oligomer, and a redox polymerization catalyst. Regarding the composition.

[Prior art and problems to be solved by the invention] In recent years, the technology of baking and curing acrylic resin at low temperatures (80 to 100°C) has not only been used from the viewpoint of saving resources and energy, but also from the viewpoint of heat resistance as a coated object. Does not have plastic material,
Realization is required from the viewpoint of making it possible to paint wood etc., and it must also be accompanied by a reduction in the amount of volatile solvent.

At present, acrylic lacquer, which is a paint that dries at room temperature, cannot provide sufficient barrier performance because it involves a reduction in molecular weight in order to reduce volatile bath agents. In addition, the two-component type polyisocyanate crosslinking has a large amount of space in the spirituality of unreacted isocyanate during coating. Furthermore, it was found that the epoxy-amine curing type had a large increase in viscosity and was not suitable for high-solidification.

[Means for solving problems]

As a result of intensive research in view of the above-mentioned circumstances, the present inventors found that
A paint resin composition containing a specific acrylic copolymer, a specific reactive oligomer, and a redox polymerization catalyst does not have the above-mentioned drawbacks even if it has a high solids content (it has excellent low-temperature curability, He discovered this and got busy completing the invention.

That is, the present invention provides (Al) a (β-methyl)glycidyl group-containing acrylic copolymer modified with a drying oil fatty acid having an iodine value of 100 to 200 (hereinafter abbreviated as modified acrylic copolymer);
Low-temperature curing with IQ of containing a reactive oligomer containing two or more unsaturated groups in one molecule (hereinafter abbreviated as unsaturated group-containing reactive oligomer) and (C) a redox polymerization catalyst. The present invention provides a high solid content resin composition with excellent properties.

The modified acrylic copolymer (A) used in the present invention includes:
For example, (β-methyl)glycidyl (meth)acrylate is used as an essential component, and other copolymerizable vinyl monomers are copolymerized with this, and then the resulting (β-methyl)glycidyl group-containing acrylic copolymer is added with iodine. Value 1
00 to 200 drying oil fatty acids (Japanese Unexamined Patent Publication No. 59-100102), and is usually in the form of a solution dissolved in a known ammonium-containing agent such as xylene, toluene, or butyl acetate. used in The concentration of this solution is usually 50-80% by weight.

The drying oil fatty acid used here has an iodine value of 100.
〜200, and such fatty acids include &E
Examples of 1"l include 1111 folic acids of natural oils and fats such as cottonseed oil, soybean oil, rice sugar oil, dehydrated castor oil, linseed oil, tall oil, and Chinese tung oil, [Pamolin 200,300J (
There are synthetic drying oils such as 111R (produced by Percules, Inc., USA), and these can be used alone or in combination in any proportion. The amount of Akima used is usually in the range of 5 to 5 parts per 100 tf parts of the (β-methyl)glycidyl group-containing acrylic copolymer, and the density of crosslinking is particularly due to the combination with a reactive oligomer containing a non-transparent phase group. The range of 15 to 40 parts by weight is particularly preferable because a coating film with excellent physical properties, solvent resistance, flexibility, etc. can be obtained.

On the other hand, the (β-methyl)glycidyl group-containing acrylic copolymer contains (β-methyl)glycidyl (meth)acrylate and another vinyl monomer copolymerizable therewith in a weight ratio of 5: A copolymerized product with a ratio of 95 to 25 Nia5 is used, but since the glycidyl group reacts with the drying oil fatty acid, the amount used is determined mainly according to the usage line of the drying oil fatty acid. IIi', this drying oil 11M ribs 0 carboxyl groups per 1 month, (
The β-methyl)glycidyl group is used in a proportion such that tO ˜1.25 equivalents.

Typical examples of other vinyl monomers copolymerizable with (β-methyl)glycidyl (meth)acrylate include:
For example, styrene, alkyl (meth)acrylate having 1 to 18 carbon atoms, (meth)acrylonitrile, vinyl chloride,
Examples include vinyl acetate. 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate as a hydroxyl group-containing vinyl monomer,
4-hydroxybutyl (meth)acrylate, hydroxyethyl vinyl ether, etc. can also be used, but the amount used must be determined so as not to cause gelation.

The unsaturated group-containing reactive oligomer (B) used in the present invention has a molecular weight soo containing two or more unsaturated groups in one molecule.

Preferably, 300 to 1500 compounds are listed below.

Examples Eva, 1,5,7-octatriene, 1-phenyl-1゜4,9-decatriene, 1-methyl-2-vinyl-4,6-hebutashenyl, 1-methyl-2-vinyl-4 , 6-hebutashenyl-1,6-nonagenoate, 1,1-bis(1'-methyl-2'-vinyl-4
', 6'-hebutadienooxy)ethane, trimethylolpropane-trimethacrylate, pentaerythritol-tetramethacrylate, triallyl formal,
triallyl isocyanurate, triallyl formal (
1,3,5-)IJ acryloylhexahydro-8-triazine), bisphenol A-dicrycidyl ether diacrylate, epoxy resin [e.g. Shell Chemical-
Examples include a compound in which 2 moles of (meth)acrylic acid is added to Ebon 828], a compound in which 2 moles of allyl glycidyl ether is added to 1 mole of adipic acid, and the structure is not particularly limited.

The ratio of the modified acrylic copolymer (excluding organic solvents such as xylene) and the unsaturated reactive oligomer (B) is generally as follows: (A): (B) = 50: 50 to 90:
(A): (B) = 60: 40 to 85: (A): (B) = 60: 40 to 85: A range of 15 is particularly preferred.

As the redox polymerization catalyst (C) used in the present invention, any known redox polymerization catalyst such as one consisting of an organic peroxide and an organic metal salt or a tertiary amine compound can be used, and there is no particular limitation.

Examples of the organic peroxide used here include hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide, di-t-butyl peroxide,
Dialkyl peroxides such as dicumyl peroxide,
Examples include t-butyl peracetate, t-butyl perbenzoate, benzoyl peroxide, methyl ethyl ketone peroxide and the like.

Examples of organic metal salts include naphthenates and octenoates of cobalt, and examples of tertiary amine compounds include N,N-dimethylaniline, N,N-
Diethylaniline, N, N-dimethyl-p-toluidine, N.

Examples include N-diethyro-p-toluidine.

The amount of the redox polymerization catalyst (C) used is determined by the amount of the modified acrylic copolymer ((trans)) and the unsaturated group-containing reactive oligomer (B).
The organic peroxide is usually α
2 to 5 parts by weight, preferably [lL5 to 6 parts by weight, organometallic salt usually cL001 to [11 parts by weight, preferably α
003 to α07 parts by weight, the 6th class amine compound is usually CL
It ranges from OI to 1.0 parts by weight, preferably from 106 to CL5 parts by weight.

The resin composition of the present invention can also contain a polyisocyanate resin, melamine formaldehyde resin, etc., if necessary.

K for obtaining the resin composition of the present invention is a predetermined amount of a modified acrylic copolymer (A) and an unsaturated group-containing reactive oligomer (B).
It is sufficient to simply mix the redox catalyst (C) and an organic bath agent such as xylene, and the modified acrylic polymer (AX) is usually used in the form of an organic solvent solution.

[Effects of the Invention] When the resin composition of the present invention obtained in this manner is used, for example, as a clear paint, it usually has a content of 50 to 50% by weight,
Preferably 60 to 75 weight 1! It is possible to paint even at a high solids concentration of -%, and at normal temperatures to 100℃,
It cures preferably at a low temperature of 60 to 80°C, and has the effect of providing a coating film with excellent performance.

(Example) The present invention will be explained in more detail by showing Reference Examples, Examples, and Comparative Examples below. Note that parts and percentages in the examples are based on weight (excluding gloss).

Reference Example 1 (Synthesis of modified acrylic copolymer) 667 parts of xylene and 2% of di-1-butyl peroxide (DTBPO) were charged into a four-bottle flask equipped with a thermometer, reflux condenser, stirrer, and nitrogen gas inlet. The temperature was raised to 125℃, and at the same temperature, styrene (St) 350
part, methyl methacrylate (MMA) 400m, n
-butyl methacrylate) (n-HMA) 55 parts,
125 parts of glycidyl methacrylate (GMA), 70 parts of ethyl acrylate (F, A), 20 parts of azobisisobutyronitrile (AIBN), 10 parts of t-butyl peroctate (TBPO) and t-butyl perbenzoate (Tspa). A mixture consisting of 7 g was added dropwise over 6 hours, and the mixture was kept at the same temperature for 5 hours after the painting was completed. When the non-volatile content reached 54%, 50 parts of linseed oil fatty acid and soybean oil fatty acid (1 d130 iodine) were added. ) and 12 parts of 2-methylimidazole (2MIZ) were added to 164 parts at the same temperature.
By performing an addition reaction between glycidyl groups and carboxyl groups, the solid content is 617% and the viscosity (same as Gardner 2 and below)
is Z4. A xylene bath solution of a soybean oil fatty acid modified acrylic copolymer having a v value of 6.0 was obtained, and 400 parts of xylene was added to this solution to adjust the solid content to about 50%.

The resin solution thus obtained is a transparent bath liquid with a nonvolatile content of 5 cL 1%, a viscosity of U-■, a color number (Gardner 2 or less) of 5, and a number average molecular weight of 6500 by gel permeation chromatography (GPC). Obtained. Below, this is a modified acrylic copolymer! - [Referred to as (I).

Reference Example 2 (same as above) 1000 g of toluene and 5 parts of DTBPo were charged in a flask similar to Reference Example 1, and the temperature was raised to 120°C. When the temperature reached the same temperature, 400 g of MMA, 254 m of EA,
A mixture consisting of 160 parts of GMA, 18 parts of AIBN, and 12s of TBPO was heated for 5 hours, and then heated to the same temperature for 10 minutes.
After holding the time and continuing Togane, the solid content was 45.1 f.
A transparent resin bath solution of o was obtained. In addition, dehydrated castor oil fatty acids (
When 216 parts of iodine value (150) was added and reacted at 120°C until the acid value was approximately 1, the solid content was 512%.
Viscosity is 2-2. A transparent toluene bath solution of a dehydrated castor oil-modified acrylic copolymer having an acid value of 1.0, a color number of 2, and a number average molecular weight of 6,500 was obtained. Hereinafter, this will be referred to as the injected acrylic melon coalescence bath solution ([).

Reference Example 6 (same as above) In a flask similar to Reference Example 1, xylene 1075m and "Pecosol J-571J [Dainippon Ink Chemical Co., Ltd. +, I
3125 parts of long oil alkyd resin manufactured by N. Co., Ltd. and 1) TBPo 4
When the temperature reached the same temperature, St 400 parts, HMA 200 parts, GMA 50 parts, H
EMA 100 copies, AN 50 copies, BA 100 copies, TBP
A mixture consisting of 18 parts of 0.018 parts and 6 parts of TBPB was applied over 5 hours, and the polymerization was continued for 12 hours.The temperature was then raised to 150°C, and 100 ttb of dehydrated castor oil was added to continue the addition reaction until the acid value was around 1. , solid content 5 cL 1%, viscosity Y, acid value t4, color number 5-6, average molecular weight.

Reference Example 4 (Synthesis of high solid content lacquer type acrylic co-container) 800s of xylene was charged in the same flask as in Reference Example 1 and heated to 1259CK4, and when the temperature reached the same temperature, 5t
350 copies, MMA 400 copies, n-BMA 2001B,
A mixture consisting of 50 parts of EA, 6 parts of AIBN, 00 parts of TBPOl, and 200 parts of xylene was added dropwise over 10 hours, and after the addition was completed, the same temperature was maintained for 5 hours to reduce the solid content to 50 parts.
%, and an acrylic copolymer with a viscosity of F was obtained. Hereinafter, this will be referred to as an acrylic copolymer (tV).

Examples 1 to 5 and Comparative Examples 1 to 2 After blending each component in the composition ratio shown in Table 1, it was diluted with xylene to obtain a resin composition for spray painting with a viscosity of Taka 4 and a Ford cup spray coating of 20 seconds. , and its solid content concentration was measured.

Next, these &4 fat compositions were placed on an iron plate that had been coated with a primer in advance so that the film thickness after drying was approximately 30 μm.
After setting for 10 minutes, force drying at 80℃ for 3 hours and leaving it for 24 hours to obtain test samples. Gopa/Coating film performance such as visibility, water resistance, and gasoline resistance was measured.

In addition, white paint film (acrylic/melamine Jugetsu 150'C)
These resin compositions were spray-painted onto the reed film (baked for 30 minutes) and dried at 80° C. for 30 minutes to obtain yellowing resistance test samples, which were used to evaluate yellowing resistance.

These results are shown in Table-1. The solid fraction measurement, water resistance test, gasoline resistance test, and yellowing resistance test were conducted as follows.

The amount of non-volatile matter produced after drying at 0 solid fraction = 105° C. for 1 hour was defined as the solid content, and the concentration was calculated.

O Water resistance: After the sample was immersed in VC water at 50° C. for 10 days, changes in the surface of the coating film were visually observed, and when there was almost no change, it was evaluated as good.

O Gasoline resistance: The degree of softening of the coating film was observed after being immersed in 8 stone silver gasoline for 1 hour. It was evaluated as good when there was almost no softening, and 90 yellowing resistance: Δb values were calculated before and after irradiation with a Sunshine Weather-Ometer for 200 hours. The smaller the Δb value, the worse the yellowing resistance Ki.

Claims (1)

[Scope of Claims] (A) A (β-methyl)glycidyl group-containing acrylic copolymer modified with a drying oil fatty acid having an iodine value of 100 to 200, and (B) containing two or more unsaturated groups in one molecule. A high-solids resin composition having excellent low-temperature curability, characterized by containing a reactive oligomer having the following properties and (C) a redox polymerization catalyst.