JP2007023224A - One-pack primer composition for modified silicone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a one-pack primer composition for modified silicones, which contains an acetate-based solvent as a main component and prevents the deterioration of curability after stored, when a reactive silyl group-containing copolymer and a curing catalyst are used as a one pack. <P>SOLUTION: This one pack composition is prepared by adding a dibasic acid dialkyl ester to a composition comprising a specific reactive silyl group-containing acrylic copolymer, a curing catalyst, and a solvent consisting mainly of an acetate-based compound. The one pack composition exhibits very high adhesiveness, greatly high elongation, and good crack followingness without lowering the curing of the composition after stored, even when exposed on an alkaline condition. When a specific amount of a ≥10C alkyl group-having alkyl (meth)acrylate monomer is further used as a copolymerization component, an adhesiveness-improving effect can be expected. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a one-component primer composition for modified silicone. More specifically, the present invention relates to a one-part primer composition for modified silicones which has improved storage stability and can be used for metals, ceramics, porcelain tiles, glass, concrete, ceramic moldings, plastics and the like.

In the field of paints and sealants, it is essential to use a primer in order to ensure adhesion to various substrates.
In particular, when used around ceramic moldings and concrete, there still remains a problem that peeling is likely to occur due to alkalinity transfer, causing a decrease in adhesiveness. In order to solve these problems, adhesion is improved by using a specific copolymer containing a reactive silyl group (see, for example, Patent Document 1).

  In recent years, in view of solvent emission regulations centering on the environment, xylene and toluene regulations are being studied by the PRTR method, and studies are being made on changing the solvent and using water. An acetate solvent can be used as a polymerization solvent or dilution solvent for a resin for a primer. However, when the resin is a reactive silyl group-containing copolymer, the curability decreases after storage when used as a one-part primer. There is.

Further, when modified silicone is used as a sealing material after applying the one-component primer composition, if the one-component primer composition has insufficient curability, there is a problem that adhesiveness after water resistance decreases. .
On the other hand, as for the sealing material, polypropylene glycol type has been studied from the viewpoint of environmental regulation of phthalate ester plasticizers such as dioctyl phthalate. When a polypropylene glycol plasticizer is blended in the sealing material, there is a problem that adhesion (also referred to as adhesiveness) decreases when the one-component primer composition is used as a primer.
: JP-A-11-209683

  As a result of intensive studies in view of the actual situation as described above, the present inventors have developed a composition comprising a specific reactive silyl group-containing acrylic copolymer, a curing catalyst, and a solvent mainly composed of an acetate ester system. By adding a fatty acid ester compound, it exhibits very high adhesion even when exposed to alkalinity without lowering the curability after storage of one liquid, and has very high elongation and follows cracks. Found that it is possible to do.

That is, the present invention is a one-component primer composition for a modified silicone containing an acetic ester solvent as a main component, wherein (A) the main chain is substantially composed of a vinyl copolymer chain, Or the side chain has the general formula (I):
R ² _a
｜
-Si- (OR ¹ ) _3-a (I)
Wherein R ¹ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 25 carbon atoms, and an aralkyl having 7 to 12 carbon atoms. A reactive silyl group-containing acrylic copolymer bonded to a carbon atom represented by a monovalent hydrocarbon group selected from a group, a represents an integer of 0 to 2, and (B) a curing catalyst, (C And 1) a one-component primer composition for modified silicones, characterized in that it comprises a dibasic acid dialkyl ester.

  In addition, the component (A) is a reactive silyl group-containing monomer (a), a (meth) acrylic acid alkyl ester monomer (b) having an alkyl group having 10 or more carbon atoms, and other copolymerizable monomers. The one-component primer composition for modified silicone according to claim 1, wherein the body (c) is copolymerized (claim 2).

  3. The modified silicone according to claim 1, wherein the (meth) acrylic acid alkyl ester monomer (b) having an alkyl group having 10 or more carbon atoms contains 2 to 50% by weight of the total amount of the polymerization components. The present invention relates to a one-component primer composition (claim 3).

  The reactive silyl group-containing acrylic copolymer (A) contains a copolymer having a glass transition temperature of 35 ° C or higher and a number average molecular weight of 6,000 or higher. It relates to the 1 component primer composition for modified silicones in any one of 1-3.

  Furthermore, the one-component composition contains (D) an aminosilane compound and / or a reaction product thereof, and relates to the one-component primer composition for modified silicone according to any one of claims 1 to 4 (claim 5). .

  Further, the component (D) is a reaction product of an aminosilane compound and an epoxysilane compound or an epoxy resin. The present invention relates to the one-component primer composition for modified silicone according to any one of claims 1 to 5.

  The one-component primer composition for modified silicones of the present invention is particularly excellent in curability after storage, excellent in bendability, adhesion to inorganic base materials, water resistance, alkali resistance, and adhesion to modified silicones. It has high strength and elongation.

  The one-component primer composition for modified silicone of the present invention is a copolymer comprising a reactive silyl group-containing monomer and other copolymerizable monomer as a resin having curability at room temperature in the presence of moisture. An acrylic copolymer is contained.

  An acrylic copolymer is a copolymer whose main chain is substantially composed of a main chain copolymerized with an acrylic monomer (hereinafter, the main chain is also substantially composed of an acrylic copolymer chain). In addition, since the reactive silyl group is contained in a form bonded to a carbon atom, the obtained one-component composition of the present invention has excellent adhesion to various substrates, particularly inorganic substrates, and has water resistance. It has excellent adhesion even when exposed to properties and alkali resistance.

  In the acrylic copolymer (A), the number of reactive silyl groups bonded to the carbon atom represented by the general formula (I) is one or more, preferably 1 per molecule of the acrylic copolymer (A). -15, more preferably 2-10 is preferable from the viewpoint that the primer formed from the composition of the present invention is excellent in adhesive strength, alkali resistance, durability and the like. When the number of reactive silyl groups is less than 1, the adhesive strength tends to be low.

  The reactive silyl group represented by the general formula (I) may be bonded to the end of the main chain of the acrylic copolymer (A), may be bonded to the side chain, You may couple | bond with the terminal and the side chain.

In the general formula (I), R ¹ is a hydrogen atom or a carbon number of 1 to 10, preferably, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, etc. It is a C1-C4 alkyl group. When the number of carbon atoms of the alkyl group exceeds 10, the reactivity of the reactive silyl group is lowered. Also, when the above is a group other than an alkyl group such as a phenyl group and a benzyl group, the reactivity of the reactive silyl group is lowered.

In the general formula (I), R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms exemplified in the above R ¹ , for example, a phenyl group, preferably a carbon number. A monovalent hydrocarbon group selected from 6 to 25 aryl groups and preferably an aralkyl group having 7 to 12 carbon atoms such as a benzyl group. In these, a C1-C4 alkyl group is preferable from the point that the composition of this invention is excellent in sclerosis | hardenability.
In the general formula (I), (R ¹ O) _3-a is selected so that 3-a is 1 or more and 3 or less, that is, a is 0 to 2, but an acrylic copolymer ( From the viewpoint that the curability of A) becomes good, a is preferably 0 or 1.

When the number of (R ¹ O) _3-a or R ² a present in general formula (I) is 2 or more, R ¹ or R ² contained in two or more may be the same or different. It may be. Moreover, as an acrylic copolymer (A), what was synthesize | combined using the monomer unit containing the reactive silyl group couple | bonded with the carbon atom represented by general formula (I) in the molecule | numerator is preferable. . The content ratio of the monomer unit in the acrylic copolymer (A) is such that the one-component primer composition for modified silicone of the present invention is excellent in curability, bendability, adhesion, and durability. 1 to 30% by weight, more preferably 2 to 20% by weight, and particularly preferably 2 to 15% by weight.

  When the amount used is less than 1% by weight, the curability tends to be insufficient, and when it exceeds 30% by weight, the storage stability tends to decrease.

  The number average molecular weight of the acrylic copolymer is preferably 2000 or more, more preferably 6000 or more, particularly preferably 10,000 or more, and more preferably 50000 or less, further preferably 25000 or less, from the viewpoint of excellent physical properties such as adhesion and durability. .

  The glass transition temperature of the acrylic copolymer is preferably 20 ° C. or higher, more preferably 35 ° C. or higher, from the viewpoint of excellent physical properties such as dryness to the touch and dust adhesion. The above is particularly preferable. If it is less than 20 degreeC, the dryness at the time of low temperature will worsen, and adhesiveness will also fall. The acrylic copolymers as described above may be used alone or in combination of two or more.

Next, an example of a method for producing an acrylic copolymer will be described.
Acrylic copolymers include, for example, monomers containing a polymerizable double bond and a reactive silyl group bonded to a carbon atom, (meth) acrylic acid and / or derivatives thereof, and other monomers used as necessary It can manufacture by polymerizing what contains. Specific examples of the monomer include, for example,

General formula (II) such as:
R ³ R ² a
｜ ｜
_{CH 2 = C-Si- (OR} 1) 3-a
(Wherein R ¹ , R ² and a are the same as above, R ³ represents a hydrogen atom or a methyl group);

General formula (III) such as:
R ³ R ² _a
｜ ｜
_{CH 2 = C-COO (CH} 2) n -Si- (OR 1) 3-a
(Wherein R ¹ , R ² , R ³ and a are the same as described above, n represents an integer of 1 to 12);
_{CH 2 = CH-CH 2 OCO} (o-C 6 H 4) COO (CH 2) 3 Si (OCH 3) 3
_{CH 2 = CH-CH 2 OCO} (o-C 6 H 4) COO (CH 2) 3 Si (CH 3) (OCH 3) 2
General formula (IV) such as:

Wherein R ¹ , R ² , R ³ , a and n are as defined above;

General formula (V):

(Wherein R ¹ , R ² , R ³ and a are the same as described above, m represents an integer of 1 to 14);

General formula (VI) such as (wherein p represents an integer of 0 to 20):

(Wherein R ¹ , R ² , R ³ , a and p are the same as above).
Etc. can be illustrated.

  Specific examples of the (meth) acrylic acid alkyl ester monomer (b) having an alkyl group having 10 or more carbon atoms include lauryl (meth) acrylate, tridecyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) ) Acrylate, docosanyl (meth) acrylate, behenyl (meth) acrylate and the like.

  The amount of the monomer (b) used is preferably 2 to 50% by weight, more preferably 5 to 25% by weight, and particularly preferably 5 to 22% by weight, based on the total amount of the polymerization components used normally. When the amount used is less than 2% by weight, the adhesion to the base material and the modified silicone is hardly exhibited, and when it exceeds 50% by weight, the drying property is lowered.

  Specific examples of the other copolymerizable monomer (c) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, benzyl (meth) ) Acrylate, cyclohexyl (meth) acrylate, trifluoroethyl (meth) acrylate, pentafluoropropyl (meth) acrylate, perfluorocyclohexyl (meth) acrylate, (meth) acrylonitrile, glycidyl (meth) acrylate, dimethylaminoethyl (meth) Acrylate, diethylaminoethyl (meth) acrylate, (meth) acrylamide, α-ethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide N-methyl (meth) acrylamide (meth) acryloylmorpholine, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, N-methylol (meth) acrylamide, Aronics M-5700, AS-macromonomer 6, compounds such as AN-6, AA-6, AB-6, AK-5 (above, manufactured by Toa Synthetic Chemical Industry Co., Ltd.), Placcel FA-1, Placcel FA-4, Placcel FM-1, Placcel FM -4 (manufactured by Daicel Chemical Industries, Ltd.), phosphate ester group-containing (meth) acrylic compounds such as condensation products of hydroxyalkyl esters of (meth) acrylic acid and phosphoric acid or phosphate esters , (Meth) acrylates containing urethane bonds and siloxane bonds, etc. And the like.

These monomers (c) may be used alone or in combination of two or more.
The amount of the monomer (c) used is preferably 5 to 95% by weight, more preferably 30 to 90% by weight, and particularly preferably 40 to 85% by weight based on the total amount of the polymerization components to be used.

  In the present invention, for the purpose of further improving the adhesion of the primer formed from the composition of the present invention obtained, for example, the segment formed by urethane bond or siloxane bond in the main chain exceeds 50% by weight. It may be introduced at the time of production of the acrylic copolymer as long as it is not present.

Specific examples of monomers other than the above monomers include aromatic hydrocarbon vinyl compounds such as styrene, α-methylstyrene, chlorostyrene, styrenesulfonic acid, 4-hydroxystyrene, vinyltoluene; maleic acid, fumaric acid , Unsaturated carboxylic acids such as itaconic acid and (meth) acrylic acid, salts thereof such as alkali metal salts, ammonium salts and amine salts; acid anhydrides of unsaturated carboxylic acids such as maleic anhydride, and these acid anhydrides Esters of unsaturated carboxylic acids such as diesters or half esters with linear or branched alcohols or amines having 1 to 20 carbon atoms; vinyl esters or allyl compounds such as vinyl acetate, vinyl propionate, diallyl phthalate; vinyl Amino group-containing vinyl such as pyridine and aminoethyl vinyl ether Amide group compounds: Itaconic acid diamide, crotonic acid amide, maleic acid diamide, fumaric acid diamide, amide group-containing vinyl compounds such as N-vinylpyrrolidone; 2-hydroxyethyl vinyl ether, methyl vinyl ether, cyclohexyl vinyl ether, vinyl chloride, vinylidene chloride , Other vinyl compounds such as chloroprene, propylene, butadiene, isoprene, fluoroolefin maleimide, N-vinylimidazole, and vinyl sulfonic acid.
These may be used alone or in combination of two or more.

  Examples of the acrylic copolymer include a hydrosilylation method or a solution polymerization method using a monomer containing a reactive silyl group described in JP-A-54-36395 and JP-A-57-55954. Azo radical polymerization such as 2,2'-azobis (2-methylbutyronitrile) using a monomer containing a reactive silyl group from the viewpoint of ease of synthesis. It is particularly preferable to produce by a solution polymerization method using an initiator.

  The solvent used in the solution polymerization method is not particularly limited as long as it is a non-aqueous solvent, but is mainly composed of acetates such as ethyl acetate and butyl acetate, preferably 75% by weight in the total solvent. % Or more, particularly 50% by weight or more, there is no particular limitation. In addition to acetates, alcohols such as methanol, isopropyl alcohol, n-butanol, isobutanol, hexanol and octanol; aliphatic hydrocarbons such as n-hexane and cyclohexane; cellosolves such as ethyl cellosolve and butyl cellosorb; cellosolve acetate and the like Ether esters such as methyl ethyl ketone, ethyl acetoacetate, acetylacetone, methyl isobutyl ketone, acetone and the like can also be used in combination.

  It is preferable not to use an aromatic solvent such as xylene, but it is preferably 15% by weight or less, more preferably 10% by weight or less in the total solvent.

In the solution polymerization, for example, n-dodecyl mercaptan, t-dodecyl mercaptan, n-butyl mercaptan, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, (CH ₃₎ O) ₃ Si—S—S—Si (OCH ₃ ) ₃ , (CH ₃ O) ₃ Si—S ₈ —Si (OCH ₃ ) ₃ or other chain transfer agents are used alone or in combination of two or more. The molecular weight of the acrylic copolymer (A) to be produced may be adjusted. In particular, when a chain transfer agent having an alkoxysilyl group in the molecule, such as γ-mercaptopropyltrimethoxysilane, is used, a reactive silyl group can be introduced at the end of the acrylic copolymer. The amount of the chain transfer agent used is preferably 0.05 to 10% by weight, more preferably 0.1 to 8% by weight, based on the total amount of the polymerization components used.

  Storage stability can be improved by further blending the component (A) with a dehydrating agent or alcohol.

  Specific examples of the dehydrating agent include, for example, methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, trimethyl orthopropionate, triethyl orthopropionate, trimethyl orthoisopropionate, triethyl orthoisopropionate, ortho Examples thereof include hydrolysable ester compounds such as trimethyl butyrate, triethyl orthobutyrate, trimethyl orthoisobutyrate, triethyl orthoisobutyrate, and the like. Among these, methyl orthoacetate is preferable from the viewpoint of dehydration effect. These may be used alone or in combination of two or more.

In addition, specific examples of the pre-alkyl alcohol include lower alcohols having 1 to 4 carbon atoms such as methanol and ethanol.
The dehydrating agent and alkyl alcohol may be added, for example, to the component before the acrylic copolymer (A) is polymerized, or may be added during the polymerization of the acrylic copolymer (A), and may be obtained. The acrylic copolymer (A) and other components may be added at the time of mixing with no particular limitation.

  The blending amount of the dehydrating agent is not particularly limited, but the dehydrating agent is usually about 0.5 to 20 parts by weight, more preferably 1 to 10 parts by weight based on 100 parts by weight of the acrylic copolymer (A) resin solid content. It is preferable that it is about a part.

  The curing catalyst which is component (B) of the present invention is a carboxylic acid type organic tin compound such as tin octylate, dibutyltin dilaurate, dioctyltin malate, sulfide type such as monobutyltin sulfide, dioctyltin mercaptide, mercaptide type organic tin compound, Organotin oxide such as dioctyltin oxide or dibutyltin oxide, organic tin oxide and ethyl silicate, ethyl silicate by weight partial hydrolysis condensate, reaction product with ester compound such as dimethyl maleate, dioctyl phthalate, etc .; Acid, monomethyl phosphate, monoethyl phosphate, monobutyl phosphate, monooctyl phosphate, monodecyl phosphate, dimethyl phosphate, diethyl phosphate, dibutyl phosphate, didecyl phosphate Hexene oxide, glycidyl methacrylate, glycidol, acrylic glycidyl ether, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, Cardura E manufactured by Yuka Shell Epoxy Co., Ltd., Yuka Shell Epoxy Co., Ltd. Reaction product of an epoxy compound such as Epicoat 828 and Epicoat 1001 made from phosphoric acid and / or monoacidic phosphate ester; organic titanate compound, organoaluminum compound; maleic acid, adipic acid, azelaic acid, sebacic acid, itacone Acid, citric acid, succinic acid, phthalic acid, trimellitic acid, pyromellitic acid, acid anhydrides thereof, acidic compounds such as p-toluenesulfonic acid, hexylamine, di-2-ethylhexylamine, N, N-dimethyl Dodecylamine Amines such as dodecylamine; amines such as these and acidic amines, N, N-dimethyldodecylamine, dodecylamine, etc .; mixtures or reactants of these amines and acidic phosphates; sodium hydroxide, Examples include alkaline compounds such as potassium hydroxide.

  Of these, organotin compounds, and reaction products of organotin compounds with ethyl silicate or ethyl silicate by weight partial hydrolysis condensate are preferable in terms of curability and adhesion.

  These curing catalysts are 0.01-20 weight part with respect to 100 weight part of acrylic copolymers (A), Preferably it is 0.1-10 weight part. When the amount used is less than 0.01 parts by weight, the curability tends to decrease, and when it exceeds 20 parts by weight, the water resistance tends to decrease.

Examples of the dibasic acid dialkyl ester as component (C) of the present invention include dimethyl malonate, dimethyl succinate, dimethyl maleate, dimethyl glutarate, dimethyl adipate, dibutyl adipate, diethyl malonate, diethyl succinate and the like. It is done.
These dibasic acid dialkyl esters are 0.5 to 100 parts by weight, preferably 2 to 50 parts by weight, and more preferably 4.5 to 30 parts by weight with respect to 100 parts by weight of the acrylic copolymer (A). If it is less than 0.5 part by weight, the effect of improving curability and the effect of improving bendability after storage is small, and if it is 100 parts by weight or more, the hardness and weather resistance tend to decrease.

  Examples of the aminosilane compound as component (D) of the present invention include aminoethylaminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyldimethoxysilane, γ-aminopropyltriethoxysilane, and γ-aminopropyl. Aminosilane compounds such as diethoxysilane; reaction products of these aminosilane compounds with epoxy compounds such as Epicoat 828 and Epicoat 1001 (above, manufactured by Yuka Shell Epoxy Co., Ltd.) and γ-glycidoxypropyltrimethoxysilane Is mentioned. These may be used alone or in combination of two or more. Among these, a combination of a reaction product of γ-aminopropyltriethoxysilane and an epoxy compound and another aminosilane compound is preferable from the viewpoint of adhesion.

  The amount of the aminosilane compound used as the component (D) of the present invention is preferably 0.1 to 50 parts by weight, more preferably 0.1 to 30 parts by weight, particularly preferably 100 parts by weight of the component (A). The range is 0.5 to 20 parts by weight. When the amount used is within these ranges, the strength at break and the elongation at break tend to increase, or the retention of these properties after the water resistance test tends to increase.

  The one-component primer composition for modified silicone of the present invention was dehydrated in advance using a dehydrating agent by adding a diluting solvent to the acrylic polymer as component (A) and dibasic acid dialkyl ester as component (C). It is preferable from the viewpoint of storage stability that a curing catalyst as the component (B) and an aminosilane compound as the component (D) are blended later.

The one-component primer composition for modified silicone of the present invention can be directly applied to various adherends, or can be applied on an old coating film or for joining a deteriorated sealing material. After applying the one-component primer composition for modified silicone, the modified silicone can be applied thereon. The method for applying the one-component primer composition for modified silicone is not particularly limited, and conventionally known application means such as application by brush, application by roll, application by spray, etc. can be widely employed. The coating amount is usually about 50 to 300 g, preferably about 50 to 150 g per portion corresponding to 1 m ² area of the adherend. In order to form a coating film on an adherend, it may be dried at room temperature after coating, or may be heated at a temperature of about 50 to 120 ° C.

Further, the one-component primer composition for modified silicone of the present invention includes, for example, titanium oxide, ultramarine blue, bitumen, zinc white, bengara, yellow lead, white lead, carbon black, transparent iron oxide, barium sulfate, talc, mica, carbonic acid. Inorganic pigments such as calcium and aluminum powder, extender pigments, azo pigments, triphenylmethane pigments, quinoline pigments, anthraquinone pigments, organic pigments such as phthalocyanine pigments; diluents, ultraviolet absorbers, light stability Additives such as additives, sagging inhibitors, leveling agents; fiber elements such as nitrocellulose and cellulose acetate butyrate; epoxy resins, melamine resins, vinyl chloride resins, urethane resins, fluororesins, chlorinated polypropylene, chlorinated rubber, polyvinyl butyral A resin such as polysiloxane may be added as appropriate.

As the modified silicone applied to the primer composition of the present invention, for example, a modified silicone sold as an MS polymer from Kaneka Corporation and marketed as a sealing material using a modified silicone resin can be used.

  Next, although the curable resin composition for coating materials of this invention is demonstrated in detail based on an Example, this invention is not limited only to this Example.

Production Example 1 (Production of acrylic copolymer (A-1))
A reaction vessel equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping funnel was charged with 50 parts by weight of butyl acetate and heated to 110 ° C. while introducing nitrogen gas. Thereafter, 6.6 parts by weight of γ-methacryloxypropyltrimethoxysilane, 14 parts by weight of stearyl methacrylate, 73 parts by weight of methyl methacrylate, 5.4 parts by weight of n-butyl acrylate, 1 part by weight of acrylamide, 18 parts by weight of butyl acetate and A mixture consisting of 0.8 parts by weight of 2,2′-azobis (2-methylbutyronitrile) was dropped at a constant rate with a dropping funnel over 5 hours.

After completion of the dropwise addition, 0.1 part by weight of 2,2′-azobis (2-methylbutyronitrile) and 13 parts by weight of butyl acetate were dropped at a constant rate over 1 hour, and then aged at 110 ° C. for 2 hours. After cooling, butyl acetate was added to the resin solution to obtain an acrylic copolymer (A) -1 having a resin solid content concentration of 40% by weight.
The number average molecular weight of the obtained acrylic copolymer (A) -1 was 16000.
The calculated glass transition temperature was 52 ° C.

Production Example 2 (Production of acrylic copolymer (A-2))
A reaction vessel equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping funnel was charged with 50 parts by weight of butyl acetate and heated to 110 ° C. while introducing nitrogen gas. Thereafter, 3.3 parts by weight of γ-methacryloxypropyltrimethoxysilane, 20 parts by weight of stearyl methacrylate, 70.7 parts by weight of methyl methacrylate, 5 parts by weight of n-butyl acrylate, 1 part by weight of acrylamide, 18 parts by weight of butyl acetate and A mixture consisting of 0.5 parts by weight of 2,2′-azobis (2-methylbutyronitrile) was dropped at a constant rate with a dropping funnel over 5 hours.

After completion of the dropwise addition, 0.1 part by weight of 2,2′-azobis (2-methylbutyronitrile) and 13 parts by weight of butyl acetate were dropped at a constant rate over 1 hour, and then aged at 110 ° C. for 2 hours. After cooling, butyl acetate was added to the resin solution to obtain an acrylic copolymer (A) -2 having a resin solid content concentration of 40% by weight.
The number average molecular weight of the obtained acrylic copolymer was 21,000.
The calculated glass transition temperature was 41 ° C.

Production Example 3 (Production of acrylic copolymer (A-3))
The same procedure as in Production Example 1 was conducted except that butyl acetate in Production Example 1 was changed to xylene.
The number average molecular weight of the obtained acrylic copolymer (A) -1 was 16000.
The calculated glass transition temperature was 52 ° C.
Various additives shown in Table 1 are blended with 100 parts by weight of the resin solid content of the acrylic copolymer (A) obtained in Production Examples 1 to 3 to obtain a one-component primer composition for modified silicone. It was. The compounding amount in Table 1 represents parts by weight.

Examples 1-6, Comparative Examples 1-2
The test was carried out in accordance with the ceramics siding sealing material testing method of the Japan Ceramics Exterior Material Association (NYG). A type I test piece was prepared using a ceramic siding material (AG-WALL (manufactured by Asahi Glass Co., Ltd.)) as a base material. The one-component primer composition obtained in Table 1 was applied to the substrate by brushing (applied amount: about 100 g / m ² ), allowed to stand at room temperature for 30 minutes, and then modified silicone (POS Seal LM (produced by Cemedine Co., Ltd.)) ) And cured at 23 ° C. for 7 days and further at 35 ° C. for 7 days (initial value: normal state). Further, the test piece immersed in water at 23 ° C. for 7 days was regarded as water resistant. These test pieces were subjected to a tensile test using an autograph manufactured by Shimadzu Corporation at a tensile speed of 5 mm / min, and the breaking strength and breaking elongation were measured. The results are shown in Table 1.

Claims (6)

A one-component primer composition for modified silicones mainly composed of an acetate solvent,
(A) The main chain is substantially composed of a vinyl copolymer chain, and the general formula (I):
R ² _a
｜
-Si- (OR ¹ ) _3-a (I)
Wherein R ¹ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 25 carbon atoms, and an aralkyl having 7 to 12 carbon atoms. A reactive silyl group-containing acrylic copolymer bonded to a carbon atom represented by a monovalent hydrocarbon group selected from a group, a represents an integer of 0 to 2, and (B) a curing catalyst, (C 1) A one-component primer composition for modified silicone, which comprises a dibasic acid dialkyl ester. Component (A) is a reactive silyl group-containing monomer (a), a (meth) acrylic acid alkyl ester monomer (b) having an alkyl group having 10 or more carbon atoms, other copolymerizable monomers ( The one-component primer composition for modified silicone according to claim 1, wherein c) is copolymerized. The 1 liquid for modified silicones in any one of Claim 1 and 2 in which the (meth) acrylic-acid alkylester monomer (b) which has a C10 or more alkyl group contains 2-50 weight% of superposition | polymerization component whole quantity. Primer composition. The reactive silyl group-containing acrylic copolymer (A) contains a copolymer having a glass transition temperature of 35 ° C or higher and a number average molecular weight of 6,000 or higher. 3. One-component primer composition for modified silicone according to any one of 3 above. The one-component primer composition for modified silicone according to any one of claims 1 to 4, wherein the one-component composition comprises (D) an aminosilane compound and / or a reaction product thereof. The component (D) is a reaction product of an aminosilane compound and an epoxysilane compound or an epoxy resin. The one-component primer composition for modified silicone according to any one of claims 1 to 5.