JP2016190973A - Silicone resin, method for the production thereof, composition and coated article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silicone resin which can conveniently form a cured product having excellent flexibility, toughness and hardness, and can be used effectively as coating materials for various base materials.SOLUTION: The silicone resin is represented by formula (1) (X is H or an unsaturated polysiloxane group; Y is a C3-10 2-valent group having an alicyclic hydrocarbon ring; Z is a (meth) acryloyl group; R1 is a methyl group; R2 is a C1-4 aliphatic hydrocarbon group or phenyl group; R3 is H or a C1-4 aliphatic hydrocarbon group; l and m are an integer including 0; n is an integer of 2-100; 10≤l+m+n≤100).SELECTED DRAWING: None

Description

  The present invention relates to a silicone resin capable of forming a cured product excellent in flexibility, toughness, and hardness, a method for producing the same, a curable resin composition containing the same, and a silicone resin-coated article on which the cured coating is formed. It is suitably used as a surface coating material for the material.

  Silicone resins are applied as coating materials on the surface of various materials typified by plastics because their cured products are excellent in heat resistance, weather resistance, and scratch resistance. Conventionally, as a method for obtaining a cured product of a silicone resin, a method of polycondensing a silanol group contained in the silicone resin is known. However, since such a condensation reaction generally requires heating for a long time, the silicone resin is present in a powdered state for a long time. Therefore, when applying a silicone resin as a coating agent, it is necessary to hold it in a clean space in order to prevent the risk of foreign matter such as dust floating in the air adhering to the silicone resin. Deterioration is a problem.

Therefore, in Patent Document 1, as a silicone resin, a (meth) acryl group, which is a radical reactive group, is introduced into a silicone chain and rapidly cured by irradiation with ultraviolet rays. Methods have been proposed to increase efficiency.
However, since this silicone resin uses γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldimethoxysilane, or the like as a raw material for introducing (meth) acrylic groups, ) Since the acrylic group is close to the silicone main chain and the degree of freedom is small, there is a drawback that the resulting cured film has insufficient flexibility and toughness. In order to improve flexibility and toughness, it is necessary to add a silane compound together with the (meth) acrylic group, and the ratio of the acrylic cross-linked portion decreases and scratch resistance decreases. Becomes difficult.

Japanese Patent Laid-Open No. 11-60687

  Therefore, the objective of this invention is providing the silicone resin which can form easily the hardened | cured material excellent in the softness | flexibility, toughness, and hardness, and can be used effectively as a coating material of various base materials.

  Therefore, as a result of various studies to obtain a silicone resin capable of giving a cured product having high hardness, flexibility and toughness, the present inventors have found that a (meth) acrylate group is introduced via an alicyclic hydrocarbon. It was found that the object of the present invention can be achieved by introducing it into the silicone main chain. In addition, such a silicone resin is produced by a production method in which a dehydrocondensation reaction between a SiH group-containing polysiloxane and a hydroxy (meth) acrylate containing an alicyclic hydrocarbon group is carried out in the presence of a basic catalyst. It has been found that any number of (meth) acrylate groups can be introduced into the silicone chain via hydrogen groups.

（ここで、Xは水素原子または下記一般式（2）で表される1価の基であり、Yは脂環式炭化水素環を有する炭素数3〜10の2価の基であり、Zは（メタ）アクリロイル基であり、R1はメチル基であり、R2は炭素数1〜4の脂肪族炭化水素基またはフェニル基であり、R3は水素原子または炭素数1〜4の脂肪族炭化水素基であり、l、m、nはそれぞれ構造単位の平均値を示し、 lは0〜30の数、mは0〜80の数、nは2〜100の数であり、lとmとnの和が10〜100である。）で表されることを特徴とするシリコーン樹脂である。

（R1〜R3、Y、Z、ｌ、ｍ、nは一般式（１）と同意であり、oは構造単位の平均値を示し、0〜10の数である。） That is, the present invention provides the following general formula (1)

(Here, X is a hydrogen atom or a monovalent group represented by the following general formula (2), Y is a C 3-10 divalent group having an alicyclic hydrocarbon ring, and Z Is a (meth) acryloyl group, R1 is a methyl group, R2 is an aliphatic hydrocarbon group or phenyl group having 1 to 4 carbon atoms, and R3 is a hydrogen atom or an aliphatic hydrocarbon having 1 to 4 carbon atoms L, m and n each represent an average value of structural units, l is a number from 0 to 30, m is a number from 0 to 80, n is a number from 2 to 100, l, m and n Is a silicone resin characterized by being represented by the following formula.

(R1 to R3, Y, Z, l, m, and n are the same as those in the general formula (1), and o represents an average value of the structural units and is a number of 0 to 10)

（ここで、R1、R2は一般式（１）と同意であり、R4は水素原子または炭素数1〜4の脂肪族炭化水素基であって、ｐ個あるR4のうちの少なくとも2 つは水素原子であり、ｐは平均値を示し、10〜100の数である。Y、Zは一般式（１）と同意である。） The present invention also provides a basic composition comprising a SiH group-containing siloxane resin represented by the following general formula (3) and an alicyclic hydrocarbon group-containing (meth) acrylate monomer represented by the following general formula (4). The above-mentioned silicone resin obtained by dehydrogenative condensation in a solvent in the presence of a catalyst.

(Wherein R1 and R2 are the same as those in the general formula (1), R4 is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and at least two of p4 R4 are hydrogen. (It is an atom, p represents an average value and is a number of 10 to 100. Y and Z are the same as those in the general formula (1).)

（ここで、R1、R2は一般式（１）と同意であり、R4は水素原子または炭素数1〜4の脂肪族炭化水素基であって、ｐ個あるR4のうちの少なくとも2 つは水素原子であり、ｐは繰返し単位数を示し、10〜100の数である。Y、Zは一般式（１）と同意である。） The present invention also provides a basic catalyst comprising a SiH group-containing siloxane resin represented by the following general formula (3) and an alicyclic hydrocarbon group-containing (meth) acrylate monomer represented by the general formula (4). The method for producing a silicone resin according to claim 1, wherein dehydrogenative condensation is carried out in a solvent in the presence of.

(Wherein R1 and R2 are the same as those in the general formula (1), R4 is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and at least two of p4 R4 are hydrogen. (It is an atom, p represents the number of repeating units and is a number of 10 to 100. Y and Z are the same as those in the general formula (1).)

  Furthermore, this invention is a curable resin composition characterized by including a radical photopolymerization initiator in the silicone resin represented by the general formula (1).

  Furthermore, the present invention is a resin-coated article characterized in that a part of or the entire surface of the film obtained by curing the curable resin composition is coated.

  According to the present invention, a silicone resin in which (meth) acrylate is introduced into a silicone main chain via an alicyclic hydrocarbon group is a resin composition containing a radical polymerization initiator, which is radically polymerized. It is possible to form a cured film that cures in a short time and that is excellent in scratch resistance, crack resistance and weather resistance.

  Hereinafter, the present invention will be described in more detail.

The silicone resin of the present invention is represented by the above general formula (1), and a (meth) acryloyl group is bonded to the silicone main chain via a divalent group having an alicyclic hydrocarbon ring.
In the general formula (1), Y is a C 3-10 divalent group having an alicyclic hydrocarbon ring, and examples of the alicyclic hydrocarbon ring include cyclopropane, cyclobutane, cyclopentane, cyclohexane, Cycloheptane, cyclooctane, cyclononane, cyclodecane, decalin, norbonane, adamantane, dicyclopentadiene and the like can be mentioned, and a cyclohexane skeleton is recommended from the viewpoint of easy reaction and availability.
X is a hydrogen atom or a monovalent group represented by the general formula (2). That is, when a part of unreacted SiH of the SiH group-containing siloxane resin represented by the general formula (3) as a raw material is converted into SiOH and does not participate in dehydration condensation, it becomes a hydrogen atom, When SiOH reacts with unreacted SiH to form a multimer such as a dimer or trimer, it becomes a monovalent group represented by the general formula (2). l and m are 0 (zero), that is, all of SiH is converted to a (meth) acryloyl group via a divalent group having an alicyclic hydrocarbon ring, and there may be no structural unit containing SiH and SiOX . In the general formula (2), m-1 means that one of the m structural units was used for crosslinking, as is clear from the comparison with the general formula (1). When m-1 is 0, that is, when there is no SiOH, the terminal structure is represented.
l, m and n each represent the number of structural units (average value), l is 0 to 30, preferably 0 to 25, m is 0 to 80, preferably 0 to 50, and n is 2 to 100, preferably 10 to 100, and the sum of l, m, and n is 10 to 10.
In the general formula (2), o represents the number of structural units (average value) and is 0 to 10.

（ここで、R⁵は水素原子または炭素数1〜4のアルキル基を示す。）
なお、一般式（１）〜（４）において、特に断りがない限り、同一の記号は同じ意味を有する。 As shown in the following reaction formula, the silicone resin of the present invention is obtained by adding a basic catalyst, preferably a hydroxylamine compound (5), to an SiH group-containing siloxane resin (3), followed by an alcoholic hydroxyl group and an alicyclic hydrocarbon. It is produced by mixing and reacting a (meth) acrylate monomer (4) having a group.

(Here, R ⁵ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)
In general formulas (1) to (4), the same symbols have the same meanings unless otherwise specified.

In the general formula (3), when R2 is an aliphatic hydrocarbon group having 1 to 4 carbon atoms, a part or all of the hydrogen atoms may be substituted with a halogen atom or a cyano group. Considering removal of by-product R ⁵ ₂ NOH as described later, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, and a propyl group is preferable.

R4 is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and may be a group in which a part or all of the hydrogen atoms are substituted with a halogen atom, a cyano group, or the like. Considering removal of by-product R ⁵ ₂ NOH, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, and a propyl group is preferable.

  And at least two of p R4 are hydrogen atoms. When the number of hydrogen atoms is 1 or less, the hardness of the cured product decreases. In particular, the ratio (molar ratio) of hydrogen atoms in p R4 is preferably 0.33 to 1. That is, 33 to 100% of R4 is preferably a hydrogen atom.

  The SiH group-containing siloxane resin represented by the general formula (3) can be produced by a known method. For example, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, or both, and a compound containing a triorganosilyl group that can be a terminal group, in the presence of an acid catalyst such as sulfuric acid, trifluoromethanesulfonic acid, or methanesulfonic acid. Therefore, it can be easily obtained by reacting at a temperature of about −10 to 40 ° C. Examples of the compound containing a triorganosilyl group include hexamethyldisiloxane.

  Moreover, as a basic catalyst used when obtaining the silicone resin of this invention, there exist hydroxylamine etc., As hydrosilamine, what is shown by the said General formula (5) can be used.

  The hydroxylamine compound functions as a catalyst in the reaction between the SiH group-containing siloxane resin represented by the formula (3) and the alicyclic hydrocarbon group-containing (meth) acrylate monomer represented by the formula (4). Is removed from the system. Therefore, below, a mixture ratio and reaction conditions are shown on the basis of SiH group of SiH group content siloxane resin denoted by a general formula (3).

  The ratio when the hydroxylamine compound (5) as a catalyst is first mixed with the SiH group-containing siloxane resin (3) is such that the ratio (k) of the hydroxyamine compound to the SiH group of the SiH group-containing siloxane resin (3). A range of 0.1 to 1 is preferable. When the ratio k exceeds 1, the hydroxylamine compound remains excessively in the reaction system, and there remains a problem in stability over time. This mixing is preferably carried out with stirring at 0 to 110 ° C, preferably 80 to 110 ° C for about 1 to 10 minutes. When the mixture is stirred at a higher temperature or for a longer time, gelation proceeds. In addition, the hydroxylamine compound after completion | finish of reaction is removed out of a system by neutralizing and washing with water.

  The alicyclic hydrocarbon group-containing (meth) acrylate monomer represented by the general formula (4) is added to a solution obtained by mixing the hydroxylamine compound (5) as a catalyst with the SiH group-containing siloxane resin (3). Thereby, the silicone resin which has an alicyclic hydrocarbon group containing (meth) acrylate group of this invention represented by the said General formula (1) can be obtained.

By connecting the (meth) acrylic group and the silicone main chain with an alicyclic hydrocarbon group that is more rigid than the straight chain hydrocarbon group, a cured film excellent in flexibility and toughness can be obtained while maintaining hardness. Examples of the skeleton structure of the alicyclic hydrocarbon group include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, decalin, norbonane, adamantane, dicyclopentadiene, etc. A cyclohexane skeleton is recommended from the viewpoint of ease of use and availability.
Here, as a specific example of the (meth) acrylate monomer containing the alcoholic hydroxyl group and alicyclic hydrocarbon group represented by the general formula (4), 4-hydroxycyclohexyl (meth) acrylate, 2-hydroxycyclohexyl ( Examples include (meth) acrylate, 3-hydroxy-1-adamantyl- (meth) acrylate, 1,4-cyclohexanedimethanol monoacrylate (CHDMMA), 1,4-cyclohexanedimethanol monomethacrylate (CHDMMMA), and the like.

  The ratio of mixing the SiH group-containing siloxane resin (3) and the alicyclic hydrocarbon group-containing (meth) acrylate monomer (4) having an alcoholic hydroxyl group is not particularly limited. A range in which the ratio (molar ratio) between the SiH group of the SiH group-containing siloxane resin (3) and the hydroxyl group of the (meth) acrylate monomer (4) is 0.2 or more, particularly 0.3 or more and 1 or less is preferable.

  The above reaction is performed at 0 to 110 ° C., preferably 80 to 110 ° C. for about 1 to 5 hours while confirming the decrease in the amount of the alicyclic hydrocarbon group-containing (meth) acrylate monomer (4) by GPC. Is preferred. If it is stirred at a higher temperature or for a longer time, it will gel. On the other hand, when the stirring reaction is performed at a lower temperature or in a shorter time, there is a concern that the progress of the reaction is insufficient and the hardness of the cured resin composition is lowered.

  In this way, the silicone resin represented by the general formula (1) can be obtained. The weight average molecular weight (Mw) of the obtained silicone resin is preferably in the range of 3000 to 50000, more preferably 4000 to 42000. If the molecular weight is lower, the hardness of the cured resin composition tends to decrease, and if it is higher, the viscosity becomes too high and the handling is hindered.

  The above reaction is preferably carried out in an organic solvent having no active hydrogen such as toluene, benzene, hexane or the like. Use of a solvent having active hydrogen such as alcohol is not preferable because it causes a side reaction with the SiH group-containing siloxane resin (3).

  The obtained silicone resin (1), that is, a silicone resin in which a (meth) acrylate group is introduced into a silicone main chain via an alicyclic hydrocarbon, has characteristics of a silicone resin excellent in heat resistance, weather resistance, etc. In order to combine the properties of an acrylate resin with excellent curability, the present invention can be cured in a short time by using a silicone resin composition containing a radical polymerization initiator that generates radicals by light as described below. The curable resin composition can be obtained.

  Photopolymerization initiators that generate radicals by light include, for example, biacetylacetophenone, benzophenone, benzyl, benzoylisobutyl ether, benzyldimethyl ketal, (1-hydroxycyclohexyl) phenylketone, (1-hydroxy-1-methylethyl) Examples include phenyl ketone, (α-hydroxyisopropyl) (p-isopropylphenyl) ketone, diethylthioxanthone, ethyl anthraquinone, bis (diethylamino) benzophenone and the like.

  The blending amount of the radical polymerization initiator is not particularly limited as long as it is an effective amount capable of exhibiting the radical polymerization effect, but is usually 0.01 to 20.0 weights with respect to 100 parts by weight of the total amount of the polymerizable components. Part, preferably about 0.1 to 10.0 parts by weight. Here, in addition to the silicone resin of the present invention described above, the polymerizable component is a component copolymerizable with a silicone resin added as necessary as described below, that is, polymerizable unsaturated at the terminal. Compounds having groups are also included.

  If the silicone resin composition of the present invention is within the range not impairing the effects of the present invention, a compound having a polymerizable unsaturated group at the terminal is used as a (meth) acrylate monomer, for example, methyl (meth) acrylate. Monoesters such as 2-hydroxyethyl (meth) acrylate, diesters such as 1,6-hexanediol di (meth) acrylate and 1,9-nonanediol di (meth) acrylate, and trimethylolpropane tri (meth) A curable resin composition may be obtained by using a triester such as acrylate, urethane acrylates or the like in combination.

  As long as the effects of the present invention are not impaired, resins other than silicone resins, such as polyamide, polyamideimide, polyurethane, polybutadiene, polychloroprene, polyether, polyester, styrene-butadiene-styrene block copolymer, petroleum resin, xylene resin , Epoxy resins, ketone resins, cellulose resins, fluorine-based oligomers, silicone-based oligomers, polysulfide-based oligomers, acrylic rubber, silicone rubber, and other resins, silica, alumina, glass beads, styrene-based polymer particles, divinylbenzene-based polymers Particles, methacrylate polymer particles, ethylene polymer particles, propylene polymer particles, and other fillers may be added. Furthermore, polymerization initiation aids, anti-aging agents, leveling agents, wettability improvements , Surfactants, plasticizers, modifiers may be added such as an ultraviolet absorber.

  A solvent may be used for the purpose of adjusting the viscosity of the silicone resin composition. Specific examples include alcohols such as ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, propylene glycol monoethyl ether, and ketones such as methyl ethyl ketone and methyl isobutyl ketone.

  In order to make the silicone resin composition of the present invention into a cured film, the curable resin composition of the present invention is first applied to a substrate and cured. Further, after providing a primer layer on the substrate, the silicone resin composition of the present invention may be applied on the primer layer and cured.

  Although it does not specifically limit as a base material, As a specific example, thermoplastic resin moldings, such as a polycarbonate, a polymethylmethacrylate, a polyethylene terephthalate, a cycloolefin polymer, are mentioned.

  The material used for the primer layer may be a normal curable resin and is not particularly limited, but specific examples include radically polymerizable (meth) acrylates. Adhesion is further improved by the radical reaction of the (meth) acrylate of the silicone resin composition of the present invention with the (meth) acrylate as a primer.

  The method of applying the silicone resin composition of the present invention on the substrate or primer layer can be appropriately selected from known application methods. For example, a casting method, a spin coating method, a spray coating method, a dip coating method, a flow coating method and the like can be mentioned.

  Next, the silicone resin composition of the present invention applied on the base material or primer layer is irradiated with UV light having a wavelength of 10 to 400 nm or visible light having a wavelength of 400 to 700 nm to be cured, thereby obtaining a silicone resin coating product. it can. In addition, before this process, you may add the process of removing volatile components, such as a solution, from a coating film by air-drying or heat-drying for a short time. The wavelength of the light to be used is not particularly limited, but near ultraviolet light having a wavelength of 200 to 400 nm is particularly preferably used. Examples of the lamp used as the ultraviolet ray generation source include a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a pulse xenon lamp, and an electrodeless discharge lamp. Each of these ultraviolet lamps is characterized by its spectral distribution, and may be selected according to the type of photoinitiator used.

  The obtained silicone resin coating of the present invention is excellent in scratch resistance, crack resistance and weather resistance.

  Hereinafter, the present invention will be described in more detail with reference to examples and the like, but the present invention is not limited thereto.

（式中、Rはメチル基であり、q= 30、r = 0である。）で表されるオルガノハイドロジェンポリシロキサン14.8 gを投入した。一方、滴下ロートにトルエン28.2 gと1,4-シクロヘキサンジメタノールモノアクリレート（CHDMMA）15.6 gの混合液を準備した。
反応容器を110℃まで昇温し、N,N−ジエチルヒドロキシルアミン89ｇを加えた後、滴下ロートからCHDMMAとトルエン混合液を30分かけて滴下した。滴下終了後、110℃で5時間攪拌した。攪拌が終了したら室温まで冷却し、クエン酸水溶液および水で中性になるまで水洗した後、無水硫酸マグネシウムを用いて脱水した。無水硫酸マグネシウムをろ別除去し、濃縮することによって、脂環式炭化水素基を介してアクリレートがシリコーン主鎖に結合したシリコーン樹脂27ｇ（回収率91％）を得た。なお、得られた樹脂をシリコーン樹脂Aとする。 Example 1
In a reaction vessel, 28.2 g of toluene and the following structural formula (i)

(In the formula, R is a methyl group, q = 30, and r = 0) 14.8 g of an organohydrogenpolysiloxane represented by the following formula was added. Meanwhile, a mixture of 28.2 g of toluene and 15.6 g of 1,4-cyclohexanedimethanol monoacrylate (CHDMMA) was prepared in a dropping funnel.
The temperature of the reaction vessel was raised to 110 ° C., 89 g of N, N-diethylhydroxylamine was added, and then a CHDMMA and toluene mixed solution was added dropwise from a dropping funnel over 30 minutes. After completion of dropping, the mixture was stirred at 110 ° C. for 5 hours. After stirring, the mixture was cooled to room temperature, washed with a citric acid aqueous solution and water until neutral, and then dehydrated using anhydrous magnesium sulfate. The anhydrous magnesium sulfate was removed by filtration and concentrated to obtain 27 g of a silicone resin (91% recovery rate) in which the acrylate was bonded to the silicone main chain via the alicyclic hydrocarbon group. The obtained resin is referred to as silicone resin A.

The obtained silicone resin A was a colorless viscous liquid that was soluble in an alcohol-based organic solvent such as propylene glycol monomethyl ether. From the GPC chart of silicone resin A, it was found that the peak of CHDMMA as a raw material was consumed by 97% compared to that before the reaction, and a resin having a weight average molecular weight (M _W ) of 40513 was obtained. From the IR analysis of silicone resin A, an acrylic group-derived peak was confirmed. Table 1 shows the number of repeats (q, r) in the formula (i) of the organohydrogenpolysiloxane used in the synthesis, the molar equivalent of CHDMMA added to the organohydrogenpolysiloxane, and the consumption of CHDMMA after the reaction. Indicates the rate. The estimated structure of the obtained silicone resin A is represented by the following structural formula (ii). In the formula (ii), o in the general formula (2) is 9, 8 is a repeating structure, and 1 is a terminal structure in which m-1 is 0.

（式中Meはメチル基を示す。以下同じ。）

(In the formula, Me represents a methyl group. The same shall apply hereinafter.)

Example 2
To the reaction vessel, 28.2 g of toluene and 14.8 g of organohydrogenpolysiloxane represented by the above structural formula (i) (wherein R is a methyl group, q = 30, r = 0) were charged. . On the other hand, a mixed solution of 28.2 g of toluene and 7.8 g of CHDMMA was prepared in a dropping funnel.
The temperature of the reaction vessel was raised to 110 ° C., 89 g of N, N-diethylhydroxylamine was added, and then a CHDMMA and toluene mixed solution was added dropwise from a dropping funnel over 15 minutes. Thereafter, in the same manner as in Example 1, 20 g of a silicone resin (recovery rate: 93%) in which an acrylate was bonded to the silicone main chain via an alicyclic hydrocarbon group was obtained. The obtained resin is designated as silicone resin B.

The obtained silicone resin B was a colorless viscous liquid that was soluble in an alcohol-based organic solvent such as propylene glycol monomethyl ether. From the GPC chart of silicone resin B, it was found that the peak of CHDMMA as a raw material was consumed by 99% compared to that before the reaction, and a resin having a weight average molecular weight (M _W ) of 30503 was obtained. From the IR analysis of silicone resin B, an acrylic group-derived peak was confirmed. Table 1 shows the number of repeats (q, r) in formula (i) of the organohydrogenpolysiloxane used, the molar equivalent of CHDMMA added to the organohydrogenpolysiloxane, and the consumption rate of CHDMMA after the reaction. Show. The estimated structure of the obtained silicone resin B is represented by the following structural formula (iii). In the formula (iii), o in the general formula (2) is 9, 8 is a repeating structure, and 1 is a terminal structure in which m-1 is 0.

Example 3
To the reaction vessel, 28.2 g of toluene and 14.7 g of organohydrogenpolysiloxane represented by the above structural formula (i) (wherein R is a methyl group, q = 10, r = 20) were charged. . On the other hand, a mixed solution of 28.2 g of toluene and 15.6 g of CHDMMA was prepared in a dropping funnel.
The temperature of the reaction vessel was raised to 110 ° C., 89 g of N, N-diethylhydroxylamine was added, and then a CHDMMA and toluene mixed solution was added dropwise from a dropping funnel over 30 minutes. In the same manner as in Example 1, 26 g (recovery rate: 96%) of a silicone resin in which an acrylate was bonded to the silicone main chain via an alicyclic hydrocarbon group was obtained. The obtained resin is designated as silicone resin C.

The obtained silicone resin C was a colorless viscous liquid soluble in an alcoholic organic solvent such as propylene glycol monomethyl ether. From the GPC chart of silicone resin C, it was found that the peak of CHDMMA as a raw material was consumed by 96% compared to that before the reaction, and a resin having a weight average molecular weight (M _W ) of 4250 was obtained. From the IR analysis of silicone resin C, an acrylic group-derived peak was confirmed. Table 1 shows the number of repetitions (m, n) in formula (i) of the organohydrogenpolysiloxane used, the molar equivalent of CHDMMA added to the organohydrogenpolysiloxane, and the consumption rate of CHDMMA after the reaction. Show. The estimated structure of the obtained silicone resin C is represented by the following structural formula (iv).

Comparative Example 1
To a reaction vessel, 28.2 g of toluene and 14.8 g of organohydrogenpolysiloxane represented by the above structural formula (i) (wherein R is a methyl group, q = 30, r = 0) were charged. . Meanwhile, 28.2 g of toluene and 11.4 g of 2-hydroxyethyl methacrylate were prepared in a dropping funnel. The temperature of the reaction vessel was raised to 110 ° C., 89 g of N, N-diethylhydroxylamine was added, and then a mixture of 2-hydroxyethyl methacrylate and toluene in the dropping funnel was added dropwise over 30 minutes. Thereafter, in the same manner as in Example 1, 22.3 g (recovery rate 97%) of a silicone resin bonded with acrylate was obtained. The obtained resin is referred to as silicone resin D.

The obtained silicone resin D was a colorless viscous liquid soluble in an alcohol-based organic solvent such as propylene glycol monomethyl ether. From the GPC chart of Silicone Resin D, it was found that 99% of the peak of 2-hydroxyethyl methacrylate, the raw material, was consumed compared to before the reaction, and a resin with a weight average molecular weight (M _W ) of 33512 was obtained. It was. From the IR analysis of silicone resin D, an acrylic group-derived peak was confirmed. Table 1 shows the number of repeating structural units (m, n) of the organohydrogenpolysiloxane used, the molar equivalent of 2-hydroxyethyl methacrylate added to the organohydrogenpolysiloxane, and the methacrylic acid after the reaction. The consumption rate of 2-hydroxyethyl is shown.

Comparative Example 2
To a reaction vessel, 28.2 g of toluene and 14.8 g of organohydrogenpolysiloxane represented by the above structural formula (i) (wherein R is a methyl group, q = 30, r = 0) were charged. . Meanwhile, 28.2 g of toluene and 5.7 g of 2-hydroxyethyl methacrylate were prepared in a dropping funnel. The temperature of the reaction vessel was raised to 110 ° C., 89 g of N, N-diethylhydroxylamine was added, and then a mixture of 2-hydroxyethyl methacrylate and toluene in the dropping funnel was added dropwise over 30 minutes. In the same manner as in Example 1, 17.4 g (recovery rate 95%) of a silicone resin bonded with acrylate was obtained. The obtained resin is referred to as silicone resin E.

  The obtained silicone resin E was a colorless viscous liquid soluble in an alcohol-based organic solvent such as propylene glycol monomethyl ether. From the GPC chart of silicone resin E, it was found that the peak of 2-hydroxyethyl methacrylate as a raw material was consumed by 97% compared to before the reaction, and a resin having a molecular weight (MW) of 24,500 was obtained. From the IR analysis of silicone resin E, an acrylic group-derived peak was confirmed. Table 1 shows the number of repeating structural units (m, n) of the organohydrogenpolysiloxane used, the molar equivalent of 2-hydroxyethyl methacrylate added to the organohydrogenpolysiloxane, and the methacrylic acid after the reaction. The consumption rate of 2-hydroxyethyl is shown.

  Table 1 shows the physical property values of the cured silicone resin films obtained in Examples 1 to 3 and Comparative Examples 1 and 2. Concerning the curing treatment of silicone resin, it consists of a radically polymerizable (meth) acrylic compound on one side of a polycarbonate (PC) resin plate (Carboglass Polish Clear, Asahi Glass) 10 cm wide x 10 cm long x 3 mm thick as a base material A primer layer is provided, and a silicone resin composition in which a photopolymerization initiator (5 wt% with respect to the silicone resin) and a solvent (400 wt% with respect to the silicone resin) are blended with the silicone resins A to E on the primer layer is flow-coated. It was applied with. Subsequently, heating was performed in an atmosphere at 80 ° C. to remove the solvent, and an ultraviolet curing treatment was performed to form a cured silicone resin film. UV curing was performed under the conditions of a lamp intensity of 230 mw and 2700 mJ.

(Abrasion resistance)
Taber abrasion test JIS R 3212 (Taper abrasion tester: Yasuda Seiki Seisakusho, wear wheel: CS10-F, 500 g, 100 revolutions), the haze (%) of the cured film was measured with a haze meter, and the initial film haze The measurement was performed according to the following criteria.
○: 10 or less ×: 10 or more

(Crack resistance)
The cured film was heated and cooled in an atmosphere of 120 ° C. for 40 minutes, and then the presence or absence of cracks was visually determined.
○: No crack ×: There is a crack

(Weatherability)
After repeating 40 cycles in the weathering accelerated weathering test, the presence or absence of cracks and peeling was visually confirmed.
○: No crack or peeling ×: Crack or peeling

From the results of Table 1, Comparative Examples 1 and 2 have insufficient toughness as a cured silicone resin film because the cured silicone resin film has cracks and peeling compared to Examples 1 to 3. It is guessed.

Claims (5)

The following general formula (1)

(Here, X is a hydrogen atom or a monovalent group represented by the following general formula (2), Y is a C 3-10 divalent group having an alicyclic hydrocarbon ring, and Z Is a (meth) acryloyl group, R1 is a methyl group, R2 is an aliphatic hydrocarbon group or phenyl group having 1 to 4 carbon atoms, and R3 is a hydrogen atom or an aliphatic hydrocarbon having 1 to 4 carbon atoms L, m and n each represent an average value of structural units, l is a number from 0 to 30, m is a number from 0 to 80, n is a number from 2 to 100, l, m and n Is a silicone resin characterized by being represented by the following formula:

(R1 to R3, Y, Z, l, m, and n are the same as those in the general formula (1), and o represents an average value of the structural units and is a number of 0 to 10) A solvent containing a SiH group-containing siloxane resin represented by the following general formula (3) and an alicyclic hydrocarbon group-containing (meth) acrylate monomer represented by the following general formula (4) in the presence of a basic catalyst: The silicone resin according to claim 1, which is obtained by dehydrogenative condensation therein.

(Wherein R1 and R2 are the same as those in the general formula (1), R4 is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and at least two of p4 R4 are hydrogen. (It is an atom, p represents an average value and is a number of 10 to 100. Y and Z are the same as those in the general formula (1).) A solvent containing a SiH group-containing siloxane resin represented by the following general formula (3) and an alicyclic hydrocarbon group-containing (meth) acrylate monomer represented by the following general formula (4) in the presence of a basic catalyst: 2. The method for producing a silicone resin according to claim 1, wherein the dehydrogenative condensation is carried out in the inside.

(Wherein R1 and R2 are the same as those in the general formula (1), R4 is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and at least two of p4 R4 are hydrogen. (It is an atom, p represents the number of repeating units and is a number of 10 to 100. Y and Z are the same as those in the general formula (1).)   2. A silicone resin composition comprising the silicone resin according to claim 1 and a radical photopolymerization initiator. 4. A silicone resin-coated article obtained by forming a film obtained by curing the curable resin composition according to claim 3 on a part of or the entire surface of a substrate.