JPH0657208A - Chipping-resistant coating composition - Google Patents

Abstract

PURPOSE:To provide a cold-setting as well as thermosetting chipping-resistant coating compsn. excellent in heat deterioration resistance, cold resistance and weatherability, well bondable to a wide variety of adherends, and capable of forming a cured product having a rubber elasticity in a wide temp. range. and hence a good shape retention in the flexing test, etc., which product is little in a decrease in adhesion due to internal strain with the lapse of time, excellent in chipping resistance and rustproofness, and free of evolution of hydrochloric acid gas being causative of acid rain as one factor of environmental destruction even at the time of combustion thereof and hence little hazardous to the environ ment. CONSTITUTION:A chipping-resistant coating compsn. comprises as the indispensable components an acrylic ester polymer or copolymer and/or methacrylic ester polymer or copolymer having reactive silicon-contg. groups, an oxyalkylene polymer having reactive silicon-contg. groups, a curing accelerator for the polymers having reactive silicon-contg. groups, an epoxy resin, and a curing agent for the epoxy resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chipping-resistant coating composition which can be used in a wide temperature range from low temperature to high temperature, and more specifically, it has excellent durability, particularly heat deterioration resistance, cold resistance, weather resistance, and adhesion. The present invention relates to a novel chipping-resistant coating composition having a good curing property, a cured product having rubber elasticity, and curability at normal temperature to high temperature, which is less harmful to environment.

[0002]

2. Description of the Related Art A curable composition mainly composed of an oxyalkylene polymer having a reactive silicon group which is water-curable at room temperature has a main glass transition temperature of around -60.degree.
Although it is excellent in cold resistance, it is known that it is thermally deteriorated when exposed to high temperatures, especially 110 ° C. or higher for a long time.

In order to solve this problem, methods such as introduction of an epoxy resin and addition of a heat anti-aging agent have been tried, but they are not sufficient, and in the field of chipping resistant coatings, 12
In some cases, the environment may be 0 ° C. or higher, and such applications that require such heat deterioration resistance are not currently available.

[0004]

SUMMARY OF THE INVENTION The present invention has been invented in order to solve the above-mentioned problems of the prior art, and is excellent in heat deterioration resistance, cold resistance and weather resistance, and has a wide range of adherends. Adheres well to cured products, and the cured product is at low temperature (-60 ° C)
Since it has rubber elasticity from high temperature to high temperature (about 150 ° C), it has good followability to bending and the like, and there is little decrease in adhesive strength over time due to internal strain, and it has excellent chipping resistance and rust resistance. Also, even when burned, there is no generation of hydrochloric acid gas, which causes acid rain, which is one of the environmental damages, and there is little damage to the environment. It is intended to provide a chipping coating composition.

[0005]

Means for Solving the Problems The inventors of the present invention have completed the present invention as a result of intensive studies to solve the above problems. The chipping-resistant coating composition of the present invention,
(A) Acrylic ester polymer or copolymer and / or methacrylic acid ester polymer or copolymer having a reactive silicon group, (B) Oxyalkylene polymer having a reactive silicon group, (C) Reactivity Silicone group-containing polymer curing accelerator, (D) epoxy resin, (E) epoxy resin curing agent,
Is an essential component.

The respective components themselves in the above (A) and (B) are disclosed in JP-A-63-112642, in which the reactive silicon group is a silicon which can be crosslinked by forming a siloxane bond. It is a functional group contained, and its representative example is represented by the following general formula (I).

[0007]

[Chemical 1]

(In the formula, R ¹ is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms or a triorganosiloxane group, X is a hydroxyl group or a different or similar hydrolyzable group, and a is 0, 1 or An integer of 2, b is an integer of 0, 1, 2 or 3 and a = 2 and does not become b = 3, m is 0 to 1
8 integer)

A preferred reactive silicon group in terms of economy is a group represented by the following general formula (II).

[0010]

[Chemical 2]

(Wherein R ¹ is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms or a triorganosiloxane group, X is a hydroxyl group or a different or similar hydrolyzable group, and n is 0, 1 or 2 integer)

A preferred specific example of the component (A) in the present invention is that it has a reactive silicon group and its molecular chain is substantially
Acrylic acid alkyl ester monomer unit and / or methacrylic acid alkyl ester monomer unit having an alkyl group having 1 to 8 carbon atoms, and acrylic acid alkyl ester monomer unit having an alkyl group having 10 or more carbon atoms and /
Alternatively, a copolymer composed of a methacrylic acid alkyl ester monomer unit can be mentioned.

The abundance ratio of the monomer unit to the above monomer unit is preferably 95: 5 to 40:60 by weight day, and 9
0:10 to 60:40 is more preferable.

The copolymer as the component (A) preferably has a number average molecular weight of 500 to 100,000 from the viewpoint of easy handling.

Polymer or copolymer (A) in the present invention
And the oxyalkylene polymer (B), the amount of the polymer or copolymer (A) is the oxyalkylene polymer (B).
A range of 5 to 5000 parts is preferable, and a range of 5 to 2000 parts is more preferable for 100 parts (parts by weight, the same applies hereinafter).

In the anti-chipping coating composition of the present invention, the curing accelerator for the reactive silicon group-containing polymer (C) is 0.1 to 100 parts (A) and (B).
It is preferably about 10 parts.

Examples of the curing accelerator include organic tin compounds, acidic phosphoric acid esters, reaction products of acidic phosphoric acid esters and amines, saturated or unsaturated polyvalent carboxylic acids, acid anhydrides thereof, and aluminum chelates. Compound,
Known silanol condensation catalysts such as organic titanate compounds may be mentioned, and one kind or two or more kinds may be used as necessary.

Specific examples of the organic tin compound include, for example, dibutyltin dilaurate, dioctyltin malate, dibutyltin acetate, dibutyltin naphthalate, stannous octylate, dibutyltin methoxide,
Examples thereof include dibutyltin diacetylacetonate and dibutyltin versatate.

Examples of the organic titanate compound include titanic acid esters such as tetrabutyl titanate, tetraisopropyl titanate and triethanolamine titanate.

In the chipping-resistant coating composition of the present invention, the epoxy resin of (D) is the same as (A) (B) 1.
It is preferably 10 to 1000 parts with respect to 00 parts.

Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin and the like, the above hydrogenated epoxy resin, novolac type epoxy resin, glycidyl ester type epoxy resin, urethane modified. Epoxy resin, nitrogen-containing epoxy resin, epoxy resin derived from alcohols, rubber modified epoxy resin derived from polybutadiene, NBR, terminal carboxyl group NBR, etc., flame-retardant epoxy resin containing bromine, alicyclic epoxy resin However, the epoxy resin is not limited to this, and any generally known epoxy resin can be used. It is also possible to use mixtures of the epoxy resins mentioned above and mixtures with monoepoxy compounds for reducing the viscosity of the epoxy resins.

In the anti-chipping coating composition of the present invention, the compounding amount of the (E) epoxy resin curing agent varies depending on the type thereof and the combination with the (D) epoxy resin. Therefore, the preferable blending amount may be determined by checking the performance each time.

As the curing agent, a polyamine compound,
Decomposition when a known overt curing agent such as modified polyamine compound, acid anhydride, polyphenol, tertiary amine compound, etc. and high melting point active hydrogen compound, tertiary amine salt, imidazole salt, Lewis acid salt, Bronsted salt, water are encountered. Known latent hardeners such as ketimine that generate an amine compound can be mentioned, but the present invention is not limited thereto, and any known hardener can be used. Further, if necessary, one kind or two or more kinds may be used, and particularly when a latent curing agent is used, one liquefaction can be performed.

Specific examples of the polyamine compound as the explicit curing agent include aliphatic polyamines such as diethylaminopropylamine, alicyclic polyamines such as polyamidoamine and isophoronediamine, and aromatic polyamines such as metaxylenediamine. .

Examples of the high melting point active hydrogen compound of the latent curing agent include dicyandiamide, organic acid hydrazides such as adipic acid dihydrazide, diaminomaleonitrile, and melamine.

The chipping-resistant coating composition also contains
Diluent (phthalic acid ester such as dibutyl phthalate, dioctyl phthalate, etc., adipic acid ester such as di2-ethylhexyl adipate, alkylbenzyl phthalate such as butylbenzyl phthalate, trimellitic acid ester, phosphoric acid ester as necessary. , Benzoic acid ester, phthalic acid polyester, adipic acid polyester, plasticizer such as epoxidized soybean oil, solvent such as methanol, ethanol, toluene, high boiling point solvent, reactive diluent, etc., filler (heavy calcium carbonate) , Light calcium carbonate, colloidal calcium carbonate, kaolin, talc, silica, titanium oxide,
Aluminum silicate, magnesium oxide, zinc oxide, carbon black, glass balloons, plastic balloons, etc.), adhesion-imparting agents (silane coupling agents such as aminosilane and epoxysilane), anti-sag agents, colorants, preservatives, UV absorption Agent, light stabilizer, heat anti-aging agent, water absorbent, foaming agent, polymer of the above (A) or (B) or (D)
It is possible to add even a slight compatible resin or the like to the epoxy resin.

[0027]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited thereto.

Synthesis Examples 1 to 5 (Meth) acrylic acid ester-based polymers shown in Table 1 were obtained according to Synthesis Examples 1 to 5 described in JP-A-63-112642. In addition, in each Example, a curable composition using the polymers of Synthesis Examples 2 to 5 instead of the polymer of Synthesis Example 1 was prepared and evaluated, and almost the same results as in each Example were obtained. .

[0029]

[Table 1]

The notes in Table 1 are as follows. * 1: Acryester S manufactured by Mitsubishi Rayon Co., Ltd. * 2: C ₁₂ and C ₁₃ mixed alkyl methacrylate manufactured by Mitsubishi Rayon Co., Ltd. * 3: γ-methacryloxypropyltrimethoxysilane * 4: γ-mercaptopropyltri Methoxysilane * 5: Azobisisobutyronitrile * 6: γ-methacryloxypropylmethyldimethoxysilane * 7: γ-mercaptopropylmethyldimethoxysilane * 8: By GPC measurement.

Synthesis Examples 6 and 7 According to Synthesis Examples 8 and 9 of JP-A-63-112642, polyoxypropylene having a group represented by the following general formula (III) at the molecular end was obtained.

[0032]

[Chemical 3]

Example 1 100 parts of a composition of the polymer of Synthesis Example 1 and the polymer of Synthesis Example 7 (a mixture of 50 parts of an acrylic polymer having a terminal silyl group and 50 parts of a polyether having a terminal silyl group),
Epoxy resin [bisphenol A with an epoxy equivalent of 190
Type epoxy resin, manufactured by Yuka Shell Epoxy Co., Ltd., trade name Epicoat 828] 50 parts, heavy calcium carbonate 50
Part, water absorbent 0.5 part, latent curing agent [tertiary amine salt, Ajinomoto Co., Inc., trade name Amicure PN-23] 1
0 part, curing accelerator [reaction product of dibutyltin oxide and dioctyl phthalate, manufactured by Sansha Kisei Co., Ltd., trade name N
o. 918] 2 parts were stirred using a Dalton type mixer and defoamed under reduced pressure to obtain a sample of one-component curable composition. The performance of the obtained sample was tested, and the results are shown in Table 2.

[0034]

[Table 2]

Various tests and evaluations in Table 2 were conducted as follows. (1) Curability: A sample was applied on a mild steel plate with a thickness of 300 μm in an atmosphere of 20 ° C. and 65% RH, and after one day, the cured state was confirmed by touching with a finger. Evaluation ◯: cured, ×: uncured A sample was applied on a mild steel plate in a thickness of 300 μm, dried in a hot air dryer atmosphere at 140 ° C. for 30 minutes, taken out and returned to room temperature, and then cured by finger touch. Evaluation ○: cured, ×: uncured

(2) Adhesiveness: Mild steel plates adhere to each other,
After curing at 0 ° C for 30 minutes, curing at 20 ° C and 65% RH for 7 days, and then performing a tensile shear test. Evaluation: Cohesive failure at 40 Kg / cm ² or more C: Cohesive failure at 20 Kg / cm ² or more

(3) Cold bending resistance: A sample was placed on a mild steel sheet for 30 minutes.
Apply 0μ thick and cure at 140 ° C for 30 minutes, then at 20 ° C ・ 6
After curing at 5% RH for 7 days, bending test is performed in an atmosphere of -40 ° C. Evaluation: No change in cured film, x: Cracking in cured film

(4) Chipping resistance: A sample was coated on a mild steel plate in a thickness of 300 μm, cured at 140 ° C. for 30 minutes, and then at 20 ° C.
・ Cured at 65% RH for 7 days and then tested for chipping resistance by dropping nuts. Evaluation: Falling nut weight 60 kg or more ×: Falling nut weight 20 kg or less

(5) Heat deterioration resistance: Mild steel plates adhere to each other,
After curing at 140 ° C. for 30 minutes, curing at 20 ° C. and 65% RH for 7 days, and then exposing at 120 ° C. for 10 days, a tensile shear test is conducted. Evaluation ○: Cohesive failure at 40 Kg / cm ² or more ×: 20 Kg / cm Interface failure at ² or less (degradation and discoloration due to heat on the adhesive surface)

(6) Anticorrosion: 300 μ of the sample on a mild steel plate
Apply thickly and cure at 140 ℃ for 30 minutes, then at 20 ℃ ・ 65%
After curing at RH for 7 days, put a knife cross cut on the cured film and conduct a salt spray test. Evaluation ◯: Rust generation width is 2 mm or less from the cut portion even after exposure for 10 days

(7) Amount of hydrogen chloride gas generated: The sample was set in a hermetically sealed volume, and dry air was sent,
Measured by heating at 210 ° C for 20 minutes and sucking the internal air into the gas detector tube.

As is clear from Table 2, the curability, adhesiveness, cold bending resistance, chipping resistance of a thin film of this composition,
Both the heat deterioration resistance and the rust prevention were good. Furthermore, no harmful hydrochloric acid gas is generated during heating.

Example 2 As a latent curing agent, an aminosilane compound [γ-aminopropyltriethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.,
Product of dehydration reaction of trade name KBE903] and carbonyl compound (methyl isobutyl ketone) (JP-A-3-2634).
21 obtained in accordance with Synthesis Example 1 of Japanese Patent Publication No. 21).
A sample of the one-component curable composition was obtained with the same composition and the same procedure as in Example 1. The performance of the obtained sample was tested, and the results are shown in Table 2.

As is clear from Table 2, the curability, adhesiveness, cold bending resistance, chipping resistance of a thin film of this composition,
Both the heat deterioration resistance and the rust prevention were good. Furthermore, no harmful hydrochloric acid gas is generated during heating.

Example 3 Using the same composition and procedure as in Example 1 except that ketimine [trade name Epicure H-5S manufactured by Yuka Shell Epoxy Co., Ltd.] was used as a latent curing agent, 1 A sample of the curable composition was obtained. The performance of the obtained sample was tested, and the results are shown in Table 2.

As is clear from Table 2, the curability, adhesiveness, cold bending resistance, chipping resistance of a thin film of this composition,
Both the heat deterioration resistance and the rust prevention were good. Furthermore, no harmful hydrochloric acid gas is generated during heating.

Example 4 A combination of the latent curing agents of Example 1 and Example 2 (10 parts each)
A sample of the one-component curable composition was obtained by the same composition and the same procedure as in Example 1 except for the above. The performance of the obtained sample was tested, and the results are shown in Table 2.

As is clear from Table 2, the curability, adhesiveness, cold bending resistance, chipping resistance of a thin film of this composition,
Both the heat deterioration resistance and the rust prevention were good. Furthermore, no harmful hydrochloric acid gas is generated during heating.

Example 5 The latent hardeners of Example 1 and Example 3 were used in combination (10 parts each).
A sample of the one-component curable composition was obtained by the same composition and the same procedure as in Example 1 except for the above. The performance of the obtained sample was tested, and the results are shown in Table 2.

As is clear from Table 2, the curability, adhesiveness, cold bending resistance, chipping resistance of a thin film of this composition,
Both the heat deterioration resistance and the rust prevention were good. Furthermore, no harmful hydrochloric acid gas is generated during heating.

Example 6 Using the latent curing agents of Examples 2 and 3 together (10 parts each)
A sample of the one-component curable composition was obtained by the same composition and the same procedure as in Example 1 except for the above. The performance of the obtained sample was tested, and the results are shown in Table 2.

As is clear from Table 2, the curability, adhesiveness, cold bending resistance, chipping resistance of a thin film of this composition,
Both the heat deterioration resistance and the rust prevention were good. Furthermore, no harmful hydrochloric acid gas is generated during heating.

Comparative Example 1 The same composition and the same composition as in Example 1 were used except that a polyether having a terminal silyl group [Kanefuchi Chemical Co., Ltd., trade name S-203] was used as the polymer composition. A sample of one-component curable composition was obtained in the procedure. The performance of the obtained sample was tested, and the results are shown in Table 2.

As is clear from Table 2, no harmful hydrochloric acid gas is generated during heating, but the thin film has low chipping resistance and poor heat deterioration resistance.

Comparative Example 2 23 parts of vinyl chloride resin, 28 parts of phthalic acid ester, 21 parts of heavy calcium carbonate, 15 parts of surface-treated calcium carbonate
Parts, blocked isocyanate 7 parts, polyamide resin 2
Parts and 4 parts of calcium oxide were mixed and dispersed using a kneader mixer. Subsequently, defoaming and stirring was performed under reduced pressure to obtain a sample. This sample is a conventional vinyl chloride plastisol-based anti-chipping coating composition. The performance of the obtained sample was tested, and the results are shown in Table 2.

As is clear from Table 2, this sample generates harmful hydrochloric acid gas when heated, and its adhesion performance and chipping resistance in a thin film are not so high, and the cold bending resistance and heat deterioration resistance are inferior. .

[0057]

As described above, the chipping-resistant coating composition of the present invention is excellent in heat deterioration resistance, cold resistance and weather resistance, adheres well to a wide range of adherends, and has a cured product at a low temperature (-60 ° C). Since it has rubber elasticity from high temperature (about 150 degrees Celsius) to high temperature (about 150 degrees Celsius), it has good followability to bending and the like, and there is little decrease in adhesive strength over time due to internal strain.
Excellent chipping resistance and rust resistance, at room temperature to high temperature (150
It has a curability of about (° C.), does not generate hydrochloric acid gas or the like that causes acid rain, which is one of the environmental damages, even when it burns, and has an effect of being less harmful to the environment. The curable composition of the present invention can also be applied to applications such as adhesives, casting materials and sealing materials.

Claims (1)

[Claims] 1. (A) Acrylic acid ester polymer or copolymer and / or methacrylic acid ester polymer or copolymer having a reactive silicon group, (B) Oxyalkylene polymer having a reactive silicon group, A chipping resistant coating composition comprising (C) a curing accelerator for a reactive silicon group-containing polymer, (D) an epoxy resin, and (E) an epoxy resin curing agent as essential components.