KR100514628B1 - Resin composition with excellent weatherability and dryness and paint composition containing it - Google Patents

Abstract

The present invention relates to a room temperature-curable resin composition comprising three components of a resin containing a carboxylic acid and a basic nitrogen atom at the same time, a resin or a compound containing an epoxide group and a hydrolyzable silyl group, and a partially esterified cellulose resin and a paint containing the same. The present invention relates to a composition, which can be cured at room temperature, has excellent weather resistance, and is resistant to contamination due to an antistatic effect by a hardening structure, and has excellent advantages in drying due to its excellent workability.

Description

Resin composition excellent in weatherability and dryness and coating composition containing same

The present invention relates to a room temperature-curable resin composition comprising three components of a resin containing a carboxylic acid and a basic nitrogen atom at the same time, a resin or a compound containing an epoxide group and a hydrolyzable silyl group, and a partially esterified cellulose resin and a paint containing the same. The present invention relates to a composition, which can be cured at room temperature, has excellent weather resistance, and is resistant to contamination due to an antistatic effect by a hardening structure, and has excellent advantages in drying due to its excellent workability.

In general, the room temperature curing system applied to the paint includes curing bisphenol-A epoxy resin with polyamine or polyamide, or a two-component curing system for reacting polyol and isocyanate, and oxidizing itself when exposed to air such as alkyd resin. The method of hardening etc. are widely known.

The coating film produced by such a curing system is macromolecularly formed by a chemical reaction to have a dense structure. Therefore, since it has high resistance to solvents and very good barrier against external substances such as water or gas, it has long-term durability compared to thermoplastic resins.

However, these paints have a number of problems, first of all, urethane is very sensitive to moisture, which is difficult to apply the coating conditions, and subsequent coatings or adhesion with the entire coating film has a disadvantage. In addition, the isocyanate used as a curing agent is harmful to the human body and its use is being avoided.

Bisphenol A type epoxy resin is one of the most used resins in the coating field. It has excellent properties such as adhesion and chemical resistance, and has excellent mechanical strength, relatively low price, and easy curing at room temperature. When used as a curing agent there are problems such as severe smell and toxicity. Because of this problem, polyamide resin is also used as a curing agent, but in this case, it is difficult to increase the degree of crosslinking as much as polyamines are used. In addition, bisphenol A type epoxy resin has poor weather resistance due to its inherent structure, and there is a yellowing phenomenon due to amine hardening, so it is difficult to apply to the external exposure site.

Therefore, various measures have been devised to solve the above problems. In particular, US Pat. No. 4,525,521 discloses a primary amine by reacting an acrylic resin containing a carboxyl group with an alkyleneamine, or an acrylic resin containing a glycidyl group with ammonia. This pendant acrylic resin is prepared, and then a method of curing it with an epoxy resin is introduced. Japanese Patent Laid-Open No. 63-30521 introduces a method of preparing a ketamine pendant resin by reacting a ketone with the acrylic resin. Doing. This method is characterized by introducing acrylic resin with excellent weather resistance and maintaining fast curing between amine and epoxy resin as it is, but it is not economical in practical application and has problems such as toxicity and handling of raw materials. Difficult to do

In addition, Japanese Patent Publication No. 63-10725 introduces a system for reacting an acrylic resin having a tertiary amine and a carboxylic acid at the same time with an epoxy. The resulting coating film has excellent weather resistance and particularly yellowing compared with epoxy-amine. There is an advantage to improve the phenomenon, but it is insufficient to ensure long-term weather resistance and has a disadvantage of somewhat slow curing.

Therefore, in the present invention, as a result of intensive studies to solve the problems of the prior art, a resin containing a carboxylic acid and a basic nitrogen atom at the same time, a resin or a compound containing an epoxide group and a hydrolyzable silyl group at the same time, and partially It has been developed a room temperature curing resin composition consisting of three components of the cellulose resin esterified with a carboxylic acid, basic nitrogen atom, epoxide group, hydrolyzable silyl group, and the durability by the complex curing reaction of the hydroxyl period It is improved and anti-fouling effect is improved by antistatic effect.

The present invention relates to a vinyl-based resin comprising (A) at least two carboxylic acids and basic nitrogen atoms simultaneously in one molecule and (B) at least one epoxide group and a hydrolyzable silyl group in one molecule at the same time. A resin composition comprising three components of a compound having both an intramolecular epoxide group and a hydrolyzable silyl group and (C) partially esterified cellulose resin, wherein the vinyl resins of components (A) and (B) A vinyl monomer having a functional group can be obtained by copolymerization with other monomers, and the compound of component (B) and component (C) can also be used in commercial products.

In more detail, component (A) is prepared by introducing carboxylic acid and basic nitrogen atom which are essential curing sites of the present invention and copolymerizing monomer having carboxylic acid or basic nitrogen atom with other copolymerizable monomers.

Monomers containing carboxylic acids include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, maleic acid monoesters, fumaric acid monoesters, itaconic acid monoesters, and the like, but are not limited thereto.

As monomers containing basic nitrogen atoms, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminopropyl (meth) acrylate, N, N -Dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, t-butylaminoethyl (meth) acrylate, t- Butylaminopropyl (meth) acrylate, and the like, but is not limited thereto.

Other monomers are used for the purpose of maintaining the main chain of the copolymer, and specific examples of the monomers which are generally highly reactive include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, normal butyl ( Meta) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, amyl (meth) acrylate, lauryl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) Methacrylic acid or acrylic acid esters, such as acrylate and butoxyethyl (meth) acrylate, dialkyl esters of unsaturated dicarboxylic acids such as itaconic acid, fumaric acid and maleic acid, styrene, α-methylstyrene, and vinyl toluene Aromatic unsaturated hydrocarbons such as ethyl vinyl ether, butyl vinyl ether, vinyl acetate, vinyl butyrate, vinyl benzoate, arc Rylonitrile, methacrylonitrile, and the like, but are not limited thereto.

In the copolymer consisting of one or two or more monomers containing the carboxylic acid, one or two or more monomers containing a basic nitrogen atom, and one or two or more other monomers, Based on the solid content, it is possible to have an acid value of 1-200, an amine value of 1-200, and an acid value of 5-80 and an amine value of 5-80 are most suitable.

As a method for producing the copolymer, various known polymerization methods are possible, and among them, solution polymerization is particularly suitable. As a polymerization initiator, azo compounds, such as azobisisobutyronitrile, azobismethylbutyronitrile, and triphenyl azobenzene, and peroxides, such as benzoyl peroxide, dietary butyl peroxide, and dietary butyl perbenzoate, are used alone or in combination. can do. The amount of the polymerization initiator is adjusted so that the number average molecular weight of the polymer is in the range of 1,000-10,000, and a chain transfer agent such as mecaptans can be used for molecular weight control as necessary.

The solid content in the solution polymerization is 30-80 parts by weight is suitable, and as a solvent, aromatic hydrocarbons such as xylene and toluene, ketones such as methyl isobutyl ketone, acetates such as butyl acetate, alcohols such as butanol may be used. The synthesis temperature is in the range of 50-200 ° C. and can be determined by the choice of initiator and solvent.

Component (B) is prepared by introducing an epoxide group and a hydrolyzable silyl group, which are essential curing sites of the present invention, and copolymerizing a monomer having an epoxide group or a hydrolyzable silyl group with other copolymerizable monomers.

Monomers containing an epoxide group include, but are not limited to, glycidyl (meth) acrylate, methylglycidyl (meth) acrylate, allyl glycidyl ether, and the like.

As monomers containing a hydrolyzable silyl group, γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropylmethyldimethoxysilane, and γ- (meth) acryloyloxypropyltri Minoxyoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyl (tri-β-methoxyethoxysilane), vinyltriacetoxysilane, and the like, but are not limited thereto.

Other monomers are used for the purpose of maintaining the main chain of the copolymer and representative examples thereof are as in component (A) above.

In the copolymer consisting of one or two or more monomers including the epoxide group, one or two or more monomers including a hydrolyzable silyl group, and one or two or more other monomers, the epoxy equivalent of the resin is based on solid content. This is possible in the 100-2,000 range, with the 150-1,000 range being the most suitable. The content of the hydrolyzable silyl group may be in the range of 0.1-10 parts by weight of silicon atoms on a solid basis, and particularly in the range of 0.5-5 parts by weight.

The manufacturing method of the said component (B) copolymer is the same as the manufacturing method of the said component (A). However, chain transfer agents of mecaptans may react with epoxide groups, so be careful to use them, and alcohol solvents may delay the curing of silyl groups.

In addition, as the component (B), a compound having an epoxide group and a hydrolyzable silyl group in one molecule can be used. These compounds are widely used commercially. Representative examples thereof include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethoxydiethoxysilane, γ-glycidoxypropyltriiminooxysilane, and the like. However, it is not limited thereto.

Component (C) is a partially esterified cellulose resin, and the esterification of the resin is carried out to have a carbon number of 1 to 18 carbon atoms such as acetic acid, propionic acid, butyric acid, caproic acid, enantiic acid, caric acid, lactic acid, stearic acid, and the like. Saturated fatty acids are most suitable, one or two or more may be used, and compatibility with components (A) and (B) should be considered first. The non-esterified hydroxyl group participates in the curing reaction to improve the overall coating durability. The hydroxyl group is 0.1-30 parts by weight and 0.5-10 is most suitable. The molecular weight of component (C) resin can range from 1,000 to 100,000, but generally, the smaller the molecular weight, the better the compatibility.

The curing reaction of components (A), (B) and (C) can be further accelerated when using a catalyst. Typical catalysts that can be used include Lewis bases such as triphenylphosphine, triphenylantimony, triethylamine, and tributylamine, metal compounds such as dibutyltin dirorate, dibutyltin diacetate, tetraisopropyl titanate, and the like. It is not limited thereto.

A cured coating film can be produced by mix | blending the component (A), (B), and (C) manufactured by the said method. At this time, the compounding ratio is suitably in the range that the epoxy equivalent of component (B) is 0.1-10 to 1 equivalent of component (A) functional group, and component (C) is 1 per 100 parts by weight of the sum of components (A) and (B). -50 parts by weight is suitable. The composition is curable at room temperature but can be heat cured in the range of 50-200 ° C. if necessary.

The paints using the compositions of the present invention are curable at room temperature and are particularly excellent in weather resistance, and exhibit excellent adhesion to most materials such as iron, aluminum, concrete, and strong durability against long-term outdoor exposure. It can be widely applied to automobile repair painting.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the scope of the present invention is not limited to the following Examples.

Production Example

(1) Preparation of component (A)

60 parts by weight of xylene and 35 parts by weight of butanol were added while supplying nitrogen to a reaction tank equipped with a condenser and capable of supplying and stirring the temperature of the contents to 118 ° C.

When the temperature of the contents is kept constant, 1 part by weight of azobisisobutyronitrile and 0.5 part by weight of butterybutylperbenzoate are dissolved in the monomer mixture of Table 1 below, and then the mixed solution is uniformly used for 4 hours using a dropping apparatus. After the dropwise addition, the holding reaction is carried out for 2 hours. Thereafter, 0.2 parts by weight of a mixed solution of tertiary butyl perbenzoate was slowly added dropwise to 5 parts by weight of xylene over 20 minutes, followed by a holding reaction for 2 hours to complete the reaction to obtain components A-1 to A-3.

The resulting polymer had a solids content of 49-51% and a number average molecular weight of 10,000-2,000.

(2) Preparation of Comparative Component (A ")

Comparative components A ″ -1 to A ″ -2 are polymerized in the same manner as in the preparation of component (A). At this time, the composition ratio of the monomer is shown in Table 1 below.

TABLE 1

(3) Preparation of component (B)

32 parts by weight of xylene and 5 parts by weight of butyl acetate are added while supplying nitrogen to the reaction tank where the condenser is attached and capable of supplying and stirring the nitrogen, and the temperature of the contents is raised to 120 ° C. When the temperature of the contents is kept constant, 3 parts by weight of azobismethylbutyronitrile is dissolved in the monomer mixture of Table 2 below, and then the mixed solution is added dropwise uniformly for 4 hours using a dropping apparatus, followed by a maintenance reaction for 2 hours. Do it. Thereafter, 0.2 parts by weight of azobismethylbutyronitrile mixed solution was slowly added dropwise to 5.86 parts of xylene over 20 minutes, followed by a holding reaction for 2 hours to complete the reaction to obtain components B-1 to B-2. .

The resulting polymer had a solids content of 69-71% and a number average molecular weight of 5,000-10,000.

(4) Preparation of Comparative Component (B ")

The comparative component (B ″) is polymerized in the same manner as in the preparation of component (B), wherein the composition ratio of monomers is shown in Table 2 below.

TABLE 2

Examples and Comparative Examples

Using the components (A) and (B) and commercially available components (B) and (C) synthesized in the preparation example, the coating material was prepared as described below and subjected to the coating film temperature test. Xylene and methyl isobutyl ketone were added to component (A) at a weight ratio of 50 to 50 so that the volume part of the paint solid was 50 to 100 parts by volume of the total paint, and then mixed at a speed of 1,500 rpm using a high speed stirrer for 5 minutes. Titanium dioxide is added to the mixture so that the volume of titanium oxide is 20 to 100 parts by volume of the paint solid, and then stirred at 2,000 rpm for 1 hour using a high speed stirrer. After stirring, add 3 parts by weight of amide thickener, 0.5 parts by weight of UV stabilizer, and component (C) to 100 parts by weight of the total paint as shown in Table 3 below. Mixing was performed for a minute to prepare a paint.

The component (B) is mixed with the paint prepared as described in Table 3 below, and the sand blasted 150 × 300 × 2 mm iron specimen is coated by an air spray method such that a dry coating film is 50 ± 10 μm. The coated specimens are tested after drying for 10 days at 25 ℃ relative humidity 50% constant temperature and humidity conditions.

Table 3 below shows the weight ratios of the components (A), (B) and (C) in the Examples and Comparative Examples and the coating film properties after drying.

* 1 CAB 531-1 ': Eastmansa cellulose acetate butyrate resin

* 2 Curing time is based on ASTM 1640.

* 3 The weatherability of discoloration and gloss retention is 300 hours under UV irradiation in accordance with ASTM D2244 and D523.

* 4 Pollution resistance during outdoor exposure is determined as follows after one year of exposure.

◎ Very good ○ Excellent △ Normal X bad

As can be seen from the results of Table 3, the coating material applied to the resin composition for coating according to the present invention has excellent dryness and excellent workability, particularly excellent weather resistance, and has excellent physical properties that are not contaminated by the external environment even during long-term outdoor exposure. It can be seen that.

The resin composition according to the present invention is curable at room temperature, has excellent weather resistance, and is resistant to contamination due to the antistatic effect of the hardened structure, and has excellent advantages in drying due to its excellent workability.

Claims (3)

Room temperature curable resin composition comprising the following components as essential components: (A) a vinyl resin containing two or more carboxylic acids and basic nitrogen atoms in a molecule at the same time; (B) a vinyl-based resin containing at least one epoxide group and a hydrolyzable silyl group in one molecule or a compound having an epoxide group and a hydrolyzable silyl group in one molecule at the same time, wherein the epoxy equivalent in the component (B) is 100- 2,000, the content of silicon atoms is 0.1-10 parts by weight based on 100 parts by weight of the component (B); And (C) partially esterified cellulose resin. Here, the said (C) component contains 0.1-30 weight part of hydroxyl groups with respect to 100 weight part of said resin compositions. The resin composition according to claim 1, wherein an acid value and an amine value of the copolymer represented by component (A) are each 1-200. 1-50 with respect to 100 weight part of the sum total of component (B) and component (A) and (B) whose epoxy equivalent is 0.1-10 with respect to 1 equivalent of component (A) and component (A) functional group of Claim 1. A two-component coating composition comprising a resin composition composed of parts by weight of component (C).