JP2574157B2 - Room temperature curable resin composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a cold-setting resin composition, and more particularly, to a cold-setting resin composition which is particularly useful as a paint for providing a cured product having high hardness.

[Prior art] Conventionally, cold-setting paints are mainly used for woodworking and plastics. For example, for woodworking, a two-pack reaction type using acrylic polyol as a main component and a polyisocyanate prepolymer as a curing agent. Acrylic urethane paint.

Further, a composition comprising a vinyl resin having a hydrolyzed silyl group at a terminal or a side chain and a curing catalyst as a composition containing a silicon compound in a room temperature curing type (JP-A-57-172950,
JP-A-58-157810) is known.

Furthermore, a compound having an epoxy group and a hydrolyzable silyl group in one molecule as a curing agent and a hydrolyzable silyl group which does not contain an epoxy group are added to a vinyl polymer having a basic nitrogen atom as a curing agent. And a compound containing a silanol group and / or a compound containing
JP-A-61-225244) is also known.

[Problems to be Solved by the Invention] In recent years, in order to prevent the surface of luxury furniture from being damaged, there has been a demand for the development of a high-hardness woodwork paint. or,
In the field of plastics, there is a need for a cold-curable coating material that can provide higher hardness.

However, the cured product obtained by using the above-mentioned conventional composition has insufficient hardness (especially insufficient low-temperature curing), and the hardness is easily affected by humidity. However, there was a problem that was reduced.

The present inventors have made intensive studies to solve the drawbacks in the prior art as described above, and as a result, they contain a polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal and an epoxy group. By blending a hydrolyzable silane compound containing an amino group as a curing agent into a mixture comprising a hydrolyzable silane compound, the hardness is remarkably improved, and a cured product having high hardness can be obtained even under high humidity. As a result, the present invention has been completed.

[Means for Solving the Problems] (1) (A) A hydrolyzable silane compound containing an epoxy group and a linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal And a curing agent mixture comprising (B) a hydrolyzable silane compound containing an amino group as a main component.

(2) A polymer composition comprising (A) a linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal and a hydrolyzable silane compound containing an epoxy group as main components. And (B) a curing agent mixture containing a hydrolyzable silane compound containing an amino group as a main component. One or both of the above-mentioned (A) polymer composition and (B) curing agent mixture may be used as a hydrating agent as an alkoxysilane crosslinking agent. A room temperature curable resin composition obtained by mixing a decomposable silane compound.

(3) A polymer composition comprising (A) a linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal and a hydrolyzable silane compound containing an epoxy group as main components. And (B) a catalyst for accelerating hydrolysis and condensation of the hydrolyzable silane compound in a room temperature-curable resin composition comprising a curing agent mixture containing a hydrolyzable silane compound containing an amino group as a main component. A room temperature curable resin composition obtained by mixing.

A polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal, which is a main element constituting the composition of the present invention, synthesizes a polymer having a free carbon-carbon double bond. It can also be adjusted by introducing a silicon atom having a hydrolyzable group into the polymer by a hydrosilylation reaction of this with a silane compound having a hydrogen atom bonded to silicon and a hydrolyzable group. It is convenient and preferable to adjust the content by copolymerizing a compound having a polymerizable double bond and having no silicon atom with a silane compound having a polymerizable double bond and a hydrolyzable group.

Typical examples of the compound having a polymerizable double bond and having no silicon atom include glycidyl methacrylate,
Glycidyl acrylate, methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-butyl methacrylate, n-butyl acrylate, 2-ethylhexyl methacrylate, 2-ethylhexyl acrylate, lauryl methacrylate, lauryl acrylate, cyclohexyl methacrylate,
In addition to methacrylic esters and acrylic esters such as cyclohexyl acrylate, 2-hydroxyethyl methacrylate and 2-hydroxyethyl acrylate, methacrylic acid, acrylic acid, acrylonitrile,
Examples include fumaric anhydride, aromatic vinyl monomers such as styrene and vinyltoluene.

Representative examples of the silane compound having a polymerizable double bond and a hydrolyzable group include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, and 3-methacryloxypropyltrimethoxysilane. Can be mentioned.

Examples of the hydrolyzable silane compound containing an epoxy group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. Is a typical example,
From the viewpoint of curability and the like, 3-glycidoxypropyltrimethoxysilane is particularly desirable. Examples of the hydrolyzable silane compound having an amino group include N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, Aminopropyltriethoxysilane and the like can be mentioned.

The room-temperature-curable resin composition of the present invention can also contain an appropriate amount of a hydrolyzable silane compound as an alkoxysilane crosslinking agent.

The silane compound can be mixed with either the polymer composition (A) or the curing agent mixture (B). Representative examples of the hydrolyzable silane compound as the alkoxysilane crosslinking agent include alkyl silicates such as ethyl silicate and methyl silicate, and partially hydrolyzed condensates of the alkyl silicates, or methyltrimethoxysilane. Alkenyl trialkoxy silanes represented by alkyltrialkoxy silanes, phenyl trialkoxy silanes represented by phenyl trimethoxy silane, and the like, and partial hydrolysis condensates of the trialkoxy silanes. .

Next, a method for producing the cold-setting resin composition of the present invention will be described.

First, the polymer composition (A) is preferably a compound having a polymerizable double bond and having no silicon atom (hereinafter referred to as a "vinyl monomer") and a polymerizable double bond and a hydrolyzable compound. A chain copolymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal is obtained by copolymerizing a silane compound having a group (hereinafter referred to as “polymerizable silane compound”). The copolymer is obtained by mixing a hydrolyzable silane compound containing an epoxy group with the copolymer. In the copolymerization, the ratio of the polymerizable silane compound to all the monomers (that is, the total amount of the vinyl monomer and the polymerizable silane compound) is 1 to 30% by weight, preferably 5 to 20%.
The mixing ratio of the hydrolyzable silane compound containing an epoxy group to the copolymer is preferably 0.1 to 1.0, and more preferably 0.3 to 0.5 by weight.
Under conditions outside these ranges, the stability of the resin composition of the present invention or the hardness of a cured product of the composition may be reduced, regardless of the range below the lower limit or the range exceeding the upper limit, or It is not preferable because the appearance of the coating film such as whitening tends to be deteriorated.

In the copolymerization of the vinyl monomer and the polymerizable silane compound, any conventionally known polymerization method can be applied, but the simplest and easiest is a radical polymerization method in an organic solvent. As the organic solvent used at this time, an organic solvent which is inert as long as it does not affect the stability of each compound used in the present invention or each reaction in producing the composition of the present invention, is a copolymerization reaction. This is advantageous in that it is easy and smooth to control Such solvents include, for example, toluene, xylene, cyclohexane, n-
Various hydrocarbons such as hexane or a high-boiling aromatic hydrocarbon solvent such as "Swazol" (trade name, manufactured by Maruzen Oil Co., Ltd.), methanol, ethanol, isopropanol,
n-propanol, n-butanol, isobutanol,
alcohols such as s-butanol and ethylene glycol monomethyl ether; methyl acetate; ethyl acetate;
And esters such as -butyl and ethyl cellosolve acetate, which can be used alone or in combination.

Next, the curing agent mixture (B) is prepared by adding a hydrolyzable silane compound having an amino group as an essential component, and optionally adding and mixing the above-mentioned organic solvents. At this time, ethyl silicate, alkyl silicates such as methyl silicate, or a partially hydrolyzed condensate of the alkyl silicate,
Or an alkyltrialkoxysilane represented by methyltrimethoxysilane, an alkenyltrialkoxysilane represented by vinyltrimethoxysilane, a phenyltrialkoxysilane represented by phenyltrimethoxysilane, or the trialkoxysilane Hydrolyzable alkoxysilanes, such as partially hydrolyzed condensates, can be added as an alkoxysilane crosslinking agent.
The amount used at this time is not limited, but is preferably 1 / weight ratio to the hydrolyzable silane compound containing an amino group.
It is easy to implement 10 to 1/2.

And the hydrolyzable alkoxysilanes as the alkoxysilane crosslinking agent are not the curing agent mixture (B),
By adding during the copolymerization of the vinyl monomer and the polymerizable silane compound or during the mixing with the hydrolyzable silane compound containing an epoxy group after the copolymerization, the polymer composition (A) is added. Or it may be used by adding to both the polymer composition (A) and the curing agent mixture (B).

Incidentally, the room temperature curable resin composition of the present invention has good curability without adding a curing catalyst, but by using a catalyst for hydrolytic condensation of each of the above hydrolyzable silane compounds, It is possible to accelerate the curing reaction and further improve the low-temperature curability. Typical examples of such a hydrolysis-condensation catalyst (C) include basic compounds such as sodium hydroxide, potassium hydroxide, sodium methylate or tetramethylammonium hydride, tetraisopropyl titanate, aluminum acetylacetone, octyl. Metal salts of organic acids such as tin acid, zinc octylate, calcium octylate, lead naphthenate, dibutyltin diacetate, dibutyltin dilaurate, or dibutyltin dimaleate;
-Acidic compounds such as toluenesulfonic acid, trichloroacetic acid and phosphoric acid.

The room-temperature-curable resin composition of the present invention comprises the polymer composition (A) and the curing agent mixture (B) prepared as described above, wherein the proportion of amino groups and epoxy groups contained in both components is epoxy group. Are mixed so as to have a molar ratio of amino group to 0.5 to 3, and if necessary, a hydrolysis-condensation catalyst as the component (C) is mixed with the polymer composition (A) and the curing agent mixture (B). It is manufactured by adding about 0.001 to 1% by weight to the total weight including the solvent.

The room-temperature-curable resin composition of the present invention further includes an organic or inorganic dye region including a pigment, a matting agent,
It is also possible to blend various additives such as ultraviolet absorbers, fillers, flow regulators, as long as these additives do not interfere with the curing reaction of the room temperature curable resin composition of the present invention. There is no problem at all.

In addition, the room temperature curable resin composition of the present invention is applied to various substrates, and then gives a cured product of high hardness by being dried at room temperature, but when it is necessary to further increase the curing speed. It does not prevent warming, nor does it reduce the benefits obtained.

The cold-curable resin composition of the present invention obtained as described above can be widely used as a paint, a surface modifier, a filler, and the like for woodwork products and various plastic products.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to only these Examples.

In the following examples, all parts and percentages are by weight unless otherwise specified.

(Preparation of Polymer Composition (A)) Preparation Example 1 100 parts of xylene and 50 parts of n-butanol were charged into a reactor equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, and were charged under a nitrogen atmosphere. After the temperature was raised to 30 ° C, 30 parts of methyl methacrylate, 10 parts of n-butyl methacrylate, 40 parts of glycidyl methacrylate, 15 parts of cyclohexyl methacrylate, 5 parts of 3-methacryloxypropyltrimethoxysilane (hereinafter abbreviated as MPOS-M) and 5 parts A mixed solution composed of 2.5 parts of an oxide catalyst (product of Nippon Oil & Fats Co., Ltd., trade name "Niper BMT" (peroxide 20%)) was added dropwise over 3 hours. The temperature was maintained at the same temperature for 3 hours after the completion of the dropwise addition to obtain a solution of the polymer composition (A-1) containing 40% of the resin component. To 100 parts of the solution of the polymer (A-1) was mixed 12 parts of 3-glycidoxypropyltrimethoxysilane (hereinafter abbreviated as GPS-M) to obtain a solution of the polymer composition (A). . This solution is referred to as a polymer composition (1A).

Preparation Examples 2 to 6 Polymers (A-2) to (A-) were prepared in the same manner as in Preparation Example 1 except that the amounts (parts) of the vinyl monomer and the polymerizable silane compound used were changed as shown in Table 1. 6) got. GPS-M was mixed with 100 parts of each of the solutions of the weight materials (A-2) to (A-6) as shown in Table 2 to obtain polymer compositions (2A) to (6A).

Examples 1-4, Comparative Examples 1 and 2, Polymer Compositions (1A)-(6A) Obtained in Preparation Examples 1-6
Was diluted with a 1: 1 mixed solvent of toluene and butyl acetate to an active ingredient concentration of 35%, and 100 parts of the diluted solution was diluted with 3-aminopropyltriethoxysilane (APS-
E) A curing agent mixture (B) consisting of 60%, 20% ethyl silicate partial hydrolyzate (ES-40 manufactured by Nippon Colcoat Co., Ltd.) and 20% ethyl cellosolve was added in the amounts shown in Table 3, and the catalyst (C) was further added. And 1 part of dibutyltin diacetate was added and mixed to prepare a curable resin composition.

Next, this curable resin composition was applied to a glass plate with a bar coater so that the dry film thickness was about 10 μm, and the relative humidity was 79 ° C. with a saturated solution of NH ₄ Cl under normal temperature and normal humidity and high humidity conditions.
Cured in a desiccator at 25 ° C.
Each cured coating film was obtained. The pencil hardness was measured to evaluate the surface scratch resistance of each of the coating films thus obtained.
The results are shown in Table 3.

Here, Comparative Example 1 is an example in which the polymer composition (A) lacks a hydrolyzable silane compound containing an epoxy group, and Comparative Example 2 is the same as the polymer composition (A). This is an example in which the polymer lacks a silicon atom bonded to a hydrolyzable group, and each has a defect that the hardness of the coating film is low or the appearance of the coating film is poor.

[Effects of the Invention] As is clear from the above examples, the present invention makes it possible to obtain a cured product having a high hardness even at a normal temperature and under a high humidity. This makes it possible to develop high-hardness paints for woodworking or plastics, and the industrial benefits are immense.

Claims (8)

(57) [Claims] 1. A polymer mainly comprising (A) a linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal and a hydrolyzable silane compound containing an epoxy group. A room-temperature curable resin composition comprising the composition and (B) a curing agent mixture containing a hydrolyzable silane compound containing an amino group as a main component. 2. A linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a terminal of a chain molecule is a compound having a polymerizable double bond and having no silicon atom. The cold-curable resin composition according to claim 1, which is obtained by copolymerization with a silane compound having a heavy bond and a hydrolyzable group. 3. A polymer mainly comprising (A) a linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal and a hydrolyzable silane compound containing an epoxy group. A curing agent mixture containing a composition and (B) a hydrolyzable silane compound containing an amino group as a main component. Either or both of the above (A) polymer composition and (B) curing agent mixture as an alkoxysilane crosslinking agent. A room temperature curable resin composition obtained by mixing a hydrolyzable silane compound of the formula (1). 4. A linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal is a compound having a polymerizable double bond and having no silicon atom. The cold-setting resin composition according to claim 3, which is obtained by copolymerization with a silane compound having a heavy bond and a hydrolyzable group. 5. The cold-setting resin composition according to claim 3, wherein the hydrolyzable silane compound as the alkoxysilane crosslinking agent is ethyl silicate or a partially hydrolyzed condensate thereof. 6. A polymer mainly composed of (A) a linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a chain molecular terminal and a hydrolyzable silane compound containing an epoxy group. Catalyst for promoting hydrolysis / condensation of the hydrolyzable silane compound to a room temperature curable resin mixture comprising a composition and (B) a curing agent mixture containing an amino group-containing hydrolyzable silane compound as a main component A room temperature curable resin composition obtained by mixing 7. A linear polymer having a silicon atom bonded to a hydrolyzable group at a side chain or a terminal of a chain molecule is a polymer having a polymerizable double bond and having no silicon atom. The cold-curable resin composition according to claim (6), which is obtained by copolymerization with a silane compound having a double bond and a hydrolyzable group. 8. The cold-setting resin composition according to claim 6, wherein the hydrolyzable silane compound as the alkoxysilane crosslinking agent is ethyl silicate or a partially hydrolyzed condensate thereof.