Organopolysiloxane having reactive silicon-containing group, production method therefor, curable composition, and cured product

Abstract

To provide a reactive silicon group-containing organopolysiloxane which has good curability even when an amine-based compound is used as a curing catalyst, and yields a cured product having excellent yellowing resistance and heat resistance.SOLUTION: A reactive silicon group-containing organopolysiloxane includes, per molecule thereof, one or more groups represented by structural formula (1) and bonded to a silicon atom. (In the formula, R1 and R2 each independently represent a hydrogen atom, a C1-C10 aliphatic saturated hydrocarbon group, or a C6-C10 aryl group; R3 each independently represent a C1-C10 aliphatic saturated hydrocarbon group or a C6-C10 aryl group; and n is an integer of 2 to 12. A line with a wavy line represents a bond).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an organopolysiloxane having a reactive silicon-containing group, a method for producing the same, a curable composition, and a cured product. More specifically, the present invention relates to an organopolysiloxane having an organic silicon group capable of reacting to form a siloxane bond as a reactive silicon-containing group, a method for producing the same, a curable composition, and a cured product.

Background Art

[0002] Since a reactive silicon group, particularly an alkoxysilyl group, has the property of hydrolytic condensation in the presence of moisture, a compound having this reactive silicon group can be used as a curable composition that crosslinks and cures in the presence of moisture or humidity. Among these compounds, those having a silicon-containing organic group such as silicone in their main chain are generally known as terminal-reactive silicones. Further, a curable composition using this has a characteristic of being liquid at room temperature and becoming a rubber elastic body by curing, and is widely used as a coating agent, an adhesive, a building sealant, etc. by utilizing this characteristic.

[0003] Room temperature curable compositions containing terminal-reactive silicones are known in various types depending on the type of the reactive silicon group. Conventionally, those in which the reactive silicon group is an alkoxysilyl group, that is, a dealcoholization type that releases alcohol and cures, do not have an unpleasant odor and do not corrode metals, and thus are preferably used for the above applications. As a representative example of this dealcoholization type, a room temperature curable composition having an alkoxysilyl-terminated silicone oil as a main agent (base polymer) as disclosed in Patent Document 1 is known.

[0004] However, in the case of a dealcoholization-type room-temperature curable composition such as Patent Document 1, compared with other conventionally known curing types such as a deoxime type, a deacetic acid type, and a deacetone type, the reactivity with moisture in the air is low, and the curability is insufficient. Therefore, in order to ensure sufficient curability at room temperature, it is generally indispensable to add a catalyst such as an organotin-based compound. However, the organotin-based compound usually used as a catalyst raises concerns about toxicity to the human body and the environment. In addition, when an organometallic catalyst such as an organotin-based compound is used in a dealcoholization-type room-temperature curable composition, there is a problem that the main chain of the silicone oil is cleaved (cracked) by the generated alcohol, resulting in poor storage stability such as a decrease in curability or an increase in viscosity over time.

[0005] Therefore, Patent Document 2 discloses a room-temperature curable composition comprising an alkoxysilyl-terminated silicone oil containing a silylene group as a linking group between an alkoxysilyl group and a silicone oil main chain in order to improve storage stability. However, although the compound of Patent Document 2 has good storage stability, on the other hand, the curability is still insufficient. In addition, when an amine-based compound is used as a curing catalyst in order to make the compound free of an organotin-based compound with concerns about toxicity, there is also a problem that the reactivity is low and the curing takes a long time.

[0006] In addition, Patent Document 3 discloses an alkoxysilyl-terminated polymer obtained by reacting a polymer having a hydroxyl group at the terminal with an isocyanatosilane or the like in order to improve reactivity. However, although the compound of Patent Document 3 is excellent in reactivity, on the other hand, since it contains a urethane or urea bond in the molecule, coloring over time is remarkable, and the yellowing resistance and heat resistance are insufficient. In addition, when producing the terminal-blocked polymer, the use of a highly toxic low-boiling isocyanatosilane and the fact that the same low-boiling isocyanatosilane can be generated by thermal decomposition of the urethane or urea bond at high temperature are regarded as problems.

[0007] Furthermore, in Patent Document 4, by using a predetermined organopolysiloxane group-containing organosilicon compound having a sulfide-methylene bond as a linking group between an alkoxysilyl group and an organopolysiloxane main chain, even when an amine-based compound is used as a curing catalyst instead of an organotin compound, it has excellent rapid curability, excellent yellowing resistance, and since isocyanatosilane is not used, it can provide a cured product with low toxicity. However, although the compound of Patent Document 4 is excellent in reactivity when an amine catalyst is used, on the other hand, it has been regarded as a problem that the cured product softens due to cleavage of the sulfide-methylene-silicon bond at high temperatures.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0009] The present invention has been made in view of the above circumstances, and an object thereof is to provide a reactive silicon group-containing organopolysiloxane that gives a cured product having good curability, excellent yellowing resistance and heat resistance even when an amine-based compound is used as a curing catalyst, and a method for producing the same.

Means for Solving the Problems

[0010] As a result of intensive studies to solve the above problems, the inventors have found that an organopolysiloxane having an organoxymethyl group as a reactive silicon group and a silyl group to which two organoxy groups are bonded has good curability even when an amine compound is used as a curing catalyst, and gives a cured product excellent in yellowing resistance and heat resistance, thus completing the present invention.

[0011] That is, the present invention relates to 1. A reactive silicon group-containing organopolysiloxane having one or more groups represented by the following structural formula (1) bonded to a silicon atom,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Advantages of the Invention

[0012] The reactive silicon group-containing organopolysiloxane of the present invention has a silyl group in which an organoxymethyl group and two organoxy groups are bonded as specific reactive silicon groups at the molecular terminals. Therefore, even when an amine compound is used as a curing catalyst instead of an organotin compound, it has good curability and gives a cured product excellent in yellowing resistance and heat resistance. The reactive silicon group-containing organopolysiloxane of the present invention having such characteristics can be suitably used as a main component (base polymer) of a coating agent, an adhesive, a sealant, or the like.

Embodiments for Carrying Out the Invention

[0013] Hereinafter, the present invention will be specifically described. The reactive silicon group-containing organopolysiloxane of the present invention is an organopolysiloxane containing one or more groups represented by the following structural formula (1) bonded to silicon atoms in one molecule.

[0014]

Chemical formula

[0015] In formula (1), R 1 and R 2 each independently represent a hydrogen atom, an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and R 3 each independently represents an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms. R 1 , R 2 and R 3Examples of the aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms include linear, cyclic, and branched groups. Specific examples thereof include linear or branched alkyl groups such as methyl, ethyl, n-propyl, i-propyl, n-butyl, s-butyl, t-butyl, n-pentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; and cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups. R 1 、R 2 and R 3 Specific examples of the aryl group having 6 to 10 carbon atoms for R

[0016] Among these, R 1 、R 2 and R 3

[0017]

[0018]

[0019] In formula (1), n is an integer of 2 to 12, preferably 2 to 8, more preferably 2 to 3, and even more preferably 2, from the viewpoint of reactivity.

[0019] In the reactive silicon group-containing organopolysiloxane of the present invention, the number of reactive silicon-containing groups represented by the above structural formula (1) contained in one molecule is 1 or more. From the viewpoints of the curability and storage stability of the composition and the mechanical properties of the cured product, it is preferably 2 to 4, more preferably 2 (for example, one each at both ends of the molecular chain of the linear organopolysiloxane).

[0020] Therefore, as the reactive silicon group-containing organopolysiloxane of the present invention, those represented by the following formula (2) are preferable. By using such a compound, the mechanical properties of the obtained cured product and the storage stability of the composition are further improved.

[0021]

Chemical formula

[0022] In formula (2), R 4 each independently represents an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms. R 4 Examples of the aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms and the aryl group having 6 to 10 carbon atoms of R 1 , R 2 and R 3 are the same as the groups exemplified above. Among them, a methyl group, an ethyl group, and a phenyl group are preferable, and a methyl group is more preferable from the viewpoint of the yellowing resistance of the cured product.

[0023] In formula (2), p is a number from 1 to 2,000. From the viewpoints of the mechanical properties of the obtained cured product and the workability of the composition, 10 to 1,500 is preferable, and 100 to 1,000 is more preferable.

[0024] The number average molecular weight of the reactive silicon group-containing organopolysiloxane of the present invention is not particularly limited. However, considering improving the workability by setting the viscosity of the curable composition containing the compound within an appropriate range and imparting sufficient curability, the number average molecular weight is preferably from 200 to 100,000, more preferably from 500 to 50,000, and even more preferably from 1,000 to 20,000. In addition, the number average molecular weight in the present invention is a polystyrene equivalent value in gel permeation chromatography (GPC) analysis (hereinafter the same).

[0025] Further, the viscosity of the reactive silicon group-containing organopolysiloxane of the present invention is not particularly limited. However, considering improving the workability by setting the viscosity of the curable composition containing the compound within an appropriate range and imparting sufficient curability, the viscosity is preferably from 2 to 100,000 mPa·s, more preferably from 5 to 50,000 mPa·s, and particularly preferably from 10 to 20,000 mPa·s. Here, the viscosity is a measured value at 25 °C using a B-type rotational viscometer.

[0026] The reactive silicon group-containing organopolysiloxane of the present invention can be obtained by subjecting an organopolysiloxane containing an alkenyl group bonded to a silicon atom (hereinafter also referred to as "alkenyl group-containing organopolysiloxane") and a disiloxane compound represented by the following formula (3) to a hydrosilylation reaction in the presence of a platinum group metal catalyst in air or an inert gas such as nitrogen.

[0027] [Chemical formula] (In the formula, R 1 , R 2 and R 3 represent the same meaning as above.)

[0028] Specific examples of the disiloxane compound represented by the above formula (3) include, but are not limited to, those represented by the following structural formula. Among these, the disiloxane compound represented by formula (5) is preferred.

[0029]

Chem.

[0030] The disiloxane compound represented by the above formula (3) can be obtained, for example, by subjecting an organoxysilane represented by the following formula (6) and a disiloxane compound represented by the following formula (7) to an equilibration reaction in the presence of an acid and water.

[0031]

Chem.

[0032] The siloxane structural units of the alkenyl group-containing organopolysiloxane are not particularly limited, and may have a linear structure, a branched structure, a cyclic structure or a crosslinked structure in the siloxane skeleton. Specific examples of the alkenyl group-containing organopolysiloxane include 1,1-divinyltetramethyldisiloxane, 1,1,1-trivinyltrimethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-divinyltetraphenyldisiloxane, 1,3-diallyltetramethyldisiloxane, 1,1,3,3-tetravinyldimethyldisiloxane, hexavinyl disiloxane, 1,3,5,7-tetravinyltetramethylcyclotetrasiloxane, dimethylpolysiloxane containing vinyl groups at both ends, diphenylpolysiloxane containing vinyl groups at both ends, dimethylpolysiloxane / diphenylpolysiloxane copolymer containing vinyl groups at both ends, methyl silicone resin containing a terminal vinyl group, phenyl silicone resin containing a terminal vinyl group, methyl / phenyl silicone resin containing a terminal vinyl group, etc. From the viewpoints of the mechanical properties of the obtained cured product and the storage stability of the composition, an alkenyl group-containing organopolysiloxane having a linear structure is preferred.

[0033] The alkenyl group is preferably a linear or branched alkenyl group having 2 to 12 carbon atoms, more preferably 2 to 8 carbon atoms. Specific examples thereof include vinyl, 1-propenyl, allyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-2-propenyl, 2-methyl-1-propenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-methyl-3-butenyl, 2-methyl-3-butenyl, 3-methyl-3-butenyl, 1,1-dimethyl-2-propenyl, 1,2-dimethyl-2-propenyl, 3-methyl-2-butenyl, 2-methyl-2-butenyl, 1-ethyl-2-propenyl, 2-ethyl-2-propenyl, 1-methyl-4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, 1-heptenyl, 2-heptenyl, 3-heptenyl, 4-heptenyl, 5-heptenyl, 6-heptenyl, 1-methyl-6-heptenyl, 1-octenyl, 2-octenyl, 3-octenyl, 4-octenyl, 5-octenyl, 6-octenyl, 7-octenyl groups and the like. Among these, a vinyl group or an allyl group is preferable, and a vinyl group is more preferable.

[0034] In the alkenyl group-containing organopolysiloxane, the number of alkenyl groups contained in one molecule is 1 or more, but from the viewpoints of the curability and storage stability of the composition and the mechanical properties of the cured product, it is preferably 2 to 4, more preferably 2 (for example, one at each end of the molecular chain of the linear organopolysiloxane).

[0035] Therefore, as the alkenyl group-containing organopolysiloxane, those represented by the following formula (4) are preferable, and by using such an alkenyl group-containing organopolysiloxane, the mechanical properties of the obtained cured product and the storage stability of the composition become further better.

[0036]

Chemical formula

[0037] In formula (4), R 5 represents an alkenyl group having 2 to 12 carbon atoms. As the alkenyl group having 2 to 12 carbon atoms of R 5 the straight-chain or branched-chain alkenyl group having 2 to 8 carbon atoms exemplified above is preferable, a vinyl group or an allyl group is more preferable, and a vinyl group is even more preferable.

[0038] Regarding the reaction ratio of the alkenyl group-containing organopolysiloxane and the disiloxane compound represented by the above formula (3), considering suppression of by-products during the hydrosilylation reaction and the storage stability of the composition and the mechanical properties of the cured product, the ratio of 0.8 to 2.5 hydrosilyl groups of the disiloxane compound represented by the above formula (3) per 1 alkenyl group in the alkenyl group-containing organopolysiloxane is preferable, and the ratio of 0.9 to 2.0 is more preferable.

[0039] The platinum group metal catalyst used in the above hydrosilylation reaction is not particularly limited, and specific examples thereof include chloroplatinic acid, an alcohol solution of chloroplatinic acid, a toluene or xylene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex, tetrakistriphenylphosphine platinum, dichlorobis(triphenylphosphine) platinum, dichlorobis(acetonitrile) platinum, dichlorobis(benzonitrile) platinum, dichlorocyclooctadiene platinum, etc., and supported catalysts such as platinum-carbon, platinum-alumina, platinum-silica, etc. Among these, from the aspect of selectivity during hydrosilylation, a zero-valent platinum complex is preferable, and a toluene or xylene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex is more preferable.

[0040] The amount of the platinum group metal catalyst used is not particularly limited, but from the viewpoints of reactivity, productivity, etc., it is preferably 0.1 to 1,000 ppm, more preferably 0.3 to 100 ppm in terms of the mass of the platinum group metal relative to the total mass of the alkenyl group-containing organopolysiloxane and the disiloxane compound represented by the above formula (3).

[0041] The above hydrosilylation reaction can be carried out without a solvent, but a solvent can also be used as necessary within a range that does not inhibit the reaction. Specific examples of the solvent that can be used include hydrocarbon solvents such as pentane, hexane, cyclohexane, heptane, isooctane, benzene, toluene, and xylene; ether solvents such as diethyl ether, tetrahydrofuran, and dioxane; ester solvents such as ethyl acetate and butyl acetate; aprotic polar solvents such as N,N-dimethylformamide; chlorinated hydrocarbon solvents such as dichloromethane and chloroform, etc. These solvents may be used alone or in combination of two or more.

[0042] The reaction temperature in the above hydrosilylation reaction is not particularly limited, but it is preferably 0 to 200 °C, more preferably 40 to 110 °C, and even more preferably 60 to 100 °C. When a solvent is used, it is preferable to carry out the reaction in the range of 0 °C to the boiling point of the solvent. The reaction time is not particularly limited and is usually about 1 to 60 hours, but preferably 1 to 24 hours.

[0043] The curable composition of the present invention (hereinafter referred to as the composition) contains at least the above-mentioned (A) alkenyl group-containing organopolysiloxane having a reactive silicon group and (B) a curing catalyst. Since the composition of the present invention contains the above-mentioned alkenyl group-containing organopolysiloxane having a reactive silicon group of the present invention, it has excellent curability and gives a cured product having resistance to yellowing and heat resistance.

[0044] The curing catalyst (B) is a component that promotes the reaction in which the hydrolyzable groups contained in the (A) organopolysiloxane containing reactive silicon groups are hydrolytically condensed with moisture in the air, and promotes the curing of the composition, and is added to cure efficiently. The curing catalyst is not particularly limited as long as it is a curing catalyst used for curing general moisture condensation curing type compositions. Specific examples thereof include alkyl tin compounds such as dibutyltin oxide and dioctyltin oxide; alkyl tin ester compounds such as dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctoate, dioctyltin dioctoate, and dioctyltin divaldate; titanates and titanium chelate compounds such as tetraisopropoxytitanium, tetra-n-butoxytitanium, tetrakis(2-ethylhexoxy)titanium, dipropoxybis(acetylacetonato)titanium, titanium diisopropoxybis(ethylacetoacetate), and titanium isopropoxyoctylene glycol, and their partial hydrolyzates; organometallic compounds such as zinc naphthenate, zinc stearate, zinc-2-ethyloctoate, iron-2-ethylhexoate, cobalt-2-ethylhexoate, manganese-2-ethylhexoate, cobalt naphthenate, aluminum trihydroxide, aluminum alcoholate, aluminum acylate, salts of aluminum acylate, aluminosiloxy compounds, and aluminum chelate compounds; aminoalkyl group-substituted alkoxysilanes such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane, bis[3-(trimethoxysilyl)propyl]amine, bis[3-(triethoxysilyl)propyl]amine, N,N’-bis[3-(trimethoxysilyl)propyl]ethane-1,2-diamine, N,N’-bis[3-(triethoxysilyl)propyl]ethane-1,2-diamine, and N-phenyl-3-aminopropyltrimethoxysilane; amine compounds such as hexylamine and dodecylamine phosphate and their salts; quaternary ammonium salts such as benzyltriethylammonium acetate; lower fatty acid salts of alkali metals such as potassium acetate, sodium acetate, and lithium oxalate;Dialkylhydroxylamines such as dimethylhydroxylamine and diethylhydroxylamine; silanes and siloxanes containing a guanidino group such as 2-[3-(trimethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine, 2-[3-(methyldimethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine, 2-[3-(triethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine, 2-[3-(methyldiethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine, 2-[3-(tris(trimethylsiloxy)silyl)propyl]-1,1,3,3-tetramethylguanidine; silanes and siloxanes containing a phosphazene base such as N,N,N’,N’,N'',N''-hexamethyl-N'''-[3-(trimethoxysilyl)propyl]-phosphorimidic triamide, etc. These may be used alone or in combination of two or more.

[0045] Among these, dioctyltin dilaurate, dioctyltin dibutyrate, tetra isopropoxytitanium, tetra n-butoxytitanium, titanium diisopropoxybis(ethylacetoacetate), 3-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, bis[3-(trimethoxysilyl)propyl]amine, N,N’-bis[3-(trimethoxysilyl)propyl]ethane-1,2-diamine, 2-[3-(trimethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine are preferred because of their more excellent reactivity. Further, from the viewpoint of the curability of the composition, dioctyltin dilaurate, dioctyltin dibutyrate, 3-aminopropyltrimethoxysilane, 2-[3-(trimethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine are more preferred. Considering making it free of organotin compounds and having lower toxicity, 3-aminopropyltrimethoxysilane and 2-[3-(trimethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine are even more preferred. From the viewpoint of the curability of the composition, 2-[3-(trimethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine is particularly preferred.

[0046] Although the addition amount of the curing catalyst is not particularly limited, considering adjusting the curing rate to an appropriate range to improve workability, 0.01 to 15 parts by mass, preferably 0.1 to 5 parts by mass, is preferable with respect to 100 parts by mass of the organopolysiloxane containing a reactive silicon group (A).

[0047] Further, for the purpose of adjusting the viscosity of the composition of the present invention to improve workability, and for the purpose of adjusting the curability of the composition, the hardness of the obtained coating film, flexibility, etc., depending on the use purpose, optionally (A) other than the organopolysiloxane containing a reactive silicon group, a silane compound containing an alkoxysilyl group, a silicone alkoxy oligomer having an alkoxysilyl group and / or a silanol group in one molecule, and one or more compounds selected from silicone resins may be added.

[0048] The silane compound containing an alkoxysilyl group is not particularly limited, and specific examples thereof include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraoctoxysilane, trialkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, 3 - glycidoxypropyltrimethoxysilane, 3 - glycidoxypropyltriethoxysilane, 3 - methacryloxypropyltrimethoxysilane, 3 - acryloxypropyltrimethoxysilane, 3 - mercaptopropyltrimethoxysilane, 3 - mercaptopropyltriethoxysilane, nonafluorohexyltrimethoxysilane, tridecafluorooctyltrimethoxysilane, polyethylene glycol methyl - 3 - trimethoxysilylpropyl ether, dialkoxysilanes such as dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, 3 - glycidoxypropylmethyldimethoxysilane, 3 - glycidoxypropylmethyldiethoxysilane, Examples of monoalkoxysilanes include trimethylmethoxysilane, trimethylethoxysilane, vinyldimethylmethoxysilane, 3-methacryloxypropyldimethylmethoxysilane, 3-methacryloxypropyldimethylethoxysilane, 3-acryloxypropyldimethylmethoxysilane, 3-acryloxypropyldimethylethoxysilane, N-2-(aminoethyl)-3-aminopropyldimethylmethoxysilane, N-2-(aminoethyl)-3-aminopropyldimethylethoxysilane, and the like.

[0049] The silicone alkoxy oligomer having an alkoxysilyl group and / or a silanol group in one molecule is not particularly limited and may be a commercially available product. Specific examples thereof include X-40-9250, X-40-9246, X-40-9225, KR-500, KR-515, KC-89S, KR-401N, X-40-9227, KR-510, KR-9218, KR-400, X-40-2327, KR-401, etc., manufactured by Shin-Etsu Chemical Co., Ltd. The silicone resin is not particularly limited and may be a commercially available product. Specific examples thereof include KR-220L, KR-251, KR-112, KR-300, KR-311, KR-480, KR-216, etc., manufactured by Shin-Etsu Chemical Co., Ltd.

[0050] Furthermore, the composition of the present invention preferably has a solvent-free form that substantially does not contain an organic solvent (which is often harmful to the human body and flammable), but a solvent can also be added and used from the viewpoints of its use and workability. Here, "substantially" means that the solvent contained in the composition is 1% by mass or less, particularly 0.1% by mass or less. The solvent is not particularly limited as long as it can dissolve the component (A). Specific examples thereof include hydrocarbon solvents such as pentane, hexane, heptane, octane, decane, and cyclohexane; aromatic solvents such as benzene, toluene, and xylene; amide solvents such as formamide, N,N-dimethylformamide, pyrrolidone, and N-methylpyrrolidone; ester solvents such as ethyl acetate, butyl acetate, γ-butyrolactone, and propylene glycol-1-monomethyl ether-2-acetate; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; and ether solvents such as diethyl ether, dibutyl ether, cyclopentyl methyl ether, tetrahydrofuran, and 1,4-dioxane. These may be used alone or in combination of two or more. Among these, from the viewpoints of solubility and volatility, etc., aromatic solvents such as toluene and xylene are preferred.

[0051] In addition, various additives such as an adhesion improver, inorganic and organic ultraviolet absorbers, a storage stability improver, a plasticizer, a filler, a pigment, and a fragrance can be added to the composition of the present invention according to the purpose of use.

[0052] By applying the composition of the present invention described above to the surface of a solid substrate and curing it to form a coating layer, a coated solid substrate can be obtained. Also, by applying the adhesive composition of the present invention to the surface of a solid substrate, further laminating another solid substrate thereon, and then curing the composition to form an adhesive layer, an adhesive laminate can be obtained. The coating method of the composition is not particularly limited, and specific examples thereof include known methods such as spray coating, spin coating, dip coating, roller coating, brush coating, bar coating, and flow coating, which can be appropriately selected and used.

[0053] The material and shape of the solid substrate are not particularly limited. Specific examples thereof include organic resin substrates such as epoxy resins, phenolic resins, polyimide resins, polycarbonate resins such as polycarbonates and polycarbonate blends, acrylic resins such as poly(methyl methacrylate), polyester resins such as poly(ethylene terephthalate), poly(butylene terephthalate), and unsaturated polyester resins, polyamide resins, acrylonitrile-styrene copolymer resins, styrene-acrylonitrile-butadiene copolymer resins, polyvinyl chloride resins, polystyrene resins, blends of polystyrene and polyphenylene ether, cellulose acetate butyrate, and polyethylene resins; metal substrates such as iron plates, copper plates, and steel plates; painted surfaces; glass; ceramics; concrete; slate plates; textiles; inorganic fillers such as wood, stone, tiles, (hollow) silica, titania, zirconia, and alumina; and glass fiber products such as glass cloth, glass tape, glass mat, and glass paper including glass fiber.

[0054] When the composition of the present invention comes into contact with moisture in the atmosphere, the hydrolysis and condensation reaction of (A) the organopolysiloxane containing a reactive silicon group proceeds. As an index of the moisture in the atmosphere, any humidity of 10 to 100% RH may be used. Generally, the higher the humidity, the faster the hydrolysis proceeds. Therefore, moisture may be added to the atmosphere if desired. The curing reaction temperature and time can be appropriately changed according to factors such as the substrate to be used, moisture concentration, catalyst concentration, and type of hydrolyzable group. The curing reaction temperature is usually preferably about 10°C to 40°C from the viewpoint of workability and the like. However, in order to accelerate the curing reaction, it may be cured by heating within a range not exceeding the heat-resistant temperature of the substrate to be used. The curing reaction time is usually about 1 minute to 1 week from the viewpoint of workability and the like.

Examples

[0055] Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In the following, the viscosity is the measured value at 25°C using a B-type rotational viscometer, and the molecular weight and degree of polymerization are the number-average molecular weight and number-average degree of polymerization in terms of polystyrene determined by GPC (gel permeation chromatography) measurement.

[0056] [1] Synthesis of disiloxane compound [Example 1-1] Synthesis of disiloxane compound a

Chemical formula

[0057] To a 300 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 200 g of trimethoxy(methoxymethyl)silane and 40.4 g of 1,1,3,3-tetramethyldisiloxane were added. While stirring at 7°C, 1.2 g of concentrated sulfuric acid (98% by mass) was added dropwise. After the addition was complete, the mixture was stirred at 25°C for 5 hours. Then, 6 g of Kyoward (registered trademark) 500SH (manufactured by Kyowa Chemical Industry Co., Ltd.) was added, and after stirring for 1 hour, the reaction solution was taken out by filtration. The reaction solution was distilled (distillation temperature 90°C, vacuum degree 17 kPa) to obtain disiloxane compound a. 1 1H-NMR (CDCl3): δ 4.46~4.61 ppm (s, 1H, -SiH), 3.41~3.34 ppm (s, 9H, -Si(OCH3)2, -OCH3), 3.15~3.13 ppm (s, 2H, -CH2-), 0.00~0.02 ppm (s, 6H, -SiCH3)

[0058] [Example 1-2] Synthesis of disiloxane compound b

Chemical formula

[0059] In a 300 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 268 g of triethoxy(ethoxymethyl)silane and 40.4 g of 1,1,3,3-tetramethyldisiloxane were added. While stirring at 7 °C, 1.2 g of concentrated sulfuric acid (98% by mass) was added dropwise. After the addition was complete, the mixture was stirred at 25 °C for 5 hours. Then, 6 g of KYOWARD (registered trademark) 500SH (manufactured by Kyowa Chemical Industry Co., Ltd.) was added and stirred for 1 hour. After that, the reaction solution was taken out by filtration, and the reaction solution was distilled (distillation temperature 90 °C, vacuum degree 17 kPa) to obtain a disiloxane compound b. 1 H-NMR (CDCl3): δ 4.46~4.61 ppm (s, 1H, -SiH), 3.85~3.63 ppm (m, 6H, -OCH2-), 1.41~1.34 ppm (m, 9H, -CH3), 0.00~0.02 ppm (s, 6H, -SiCH3)

[0060] [Example 1-3] Synthesis of disiloxane compound c

Chemical formula

[0061] In a 300 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 200 g of trimethoxy(methoxymethyl)silane and 115 g of 1,1,3,3-tetraphenyldisiloxane were added. While stirring at 7 °C, 1.2 g of concentrated sulfuric acid (98% by mass) was added dropwise. After the addition was complete, the mixture was stirred at 25 °C for 5 hours. Then, 6 g of KYOWARD (registered trademark) 500SH (manufactured by Kyowa Chemical Industry Co., Ltd.) was added and stirred for 1 hour. After that, the reaction solution was taken out by filtration, and the reaction solution was distilled (distillation temperature 90 °C, vacuum degree 17 kPa) to obtain a disiloxane compound c. 1 H-NMR (CDCl3): δ 7.58~7.32 ppm (m, 10H, -SiC6H5), 4.46~4.61 ppm (s, 1H, -SiH), 3.41~3.34 ppm (s, 9H, -Si(OCH3)2, -OCH3), 3.15~3.13 ppm (s, 2H, -CH2-)

[0062] [2] Synthesis of reactive silicon group-containing organopolysiloxane [Example 2-1] Synthesis of organopolysiloxane A-1 containing reactive silicon group Into a 200 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 100 g (0.015 mol in terms of vinyl groups) of dimethylpolysiloxane blocked with vinyl dimethylsiloxy groups at both ends having a number average molecular weight of 13,600 and a toluene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (50 ppm as platinum) were added, and the mixture was heated to 60°C. 7.36 g (0.030 mol in terms of hydrosilyl groups) of the disiloxane compound a was added thereto, and the mixture was stirred at 60°C for 2 hours. 1 It was confirmed by 1H-NMR measurement that the peak derived from the vinyl group of the raw material completely disappeared and the peak derived from the target product was detected, and the reaction was terminated. After the reaction was completed, the solvent was distilled off at 100°C and a vacuum degree of 1.3 kPa for 3 hours to obtain a reactive silicon group-containing organopolysiloxane A-1. The obtained reactive silicon group-containing organopolysiloxane A-1 was a colorless transparent liquid, having a number average molecular weight of 15,000 and a viscosity of 610 mPa·s.

[0063] [Example 2-2] Synthesis of organopolysiloxane A-2 containing reactive silicon group Into a 200 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 100 g (0.0051 mol in terms of vinyl groups) of dimethylpolysiloxane blocked with vinyl dimethylsiloxy groups at both ends having a number average molecular weight of 39,900 and a toluene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (50 ppm as platinum) were added, and the mixture was heated to 60°C. 2.50 g (0.03 mol in terms of hydrosilyl groups) of the disiloxane compound a was added thereto, and the mixture was stirred at 60°C for 2 hours. 1 It was confirmed by 1H-NMR measurement that the peak derived from the vinyl group of the raw material completely disappeared and the peak derived from the target product was detected, and the reaction was terminated. After the reaction was completed, the solvent was distilled off at 100°C and a vacuum degree of 1.3 kPa for 3 hours to obtain a reactive silicon group-containing organopolysiloxane A-2. The obtained reactive silicon group-containing organopolysiloxane A-2 was a colorless transparent liquid, having a number average molecular weight of 41,500 and a viscosity of 11,000 mPa·s.

[0064] [Example 2-3] Synthesis of organopolysiloxane A-3 containing reactive silicon group Into a 200 mL separable flask equipped with a stirrer, a reflux condenser and a thermometer, 100 g (0.015 mol in terms of vinyl group) of a dimethylpolysiloxane blocked with vinyl dimethylsiloxy groups at both ends with a number average molecular weight of 13,600 and a toluene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (50 ppm in terms of platinum) were added and heated to 60°C. 9.00 g (0.030 mol in terms of hydrosilyl group) of the disiloxane compound b was added thereto and stirred at 60°C for 2 hours. 1 By 1H-NMR measurement, it was confirmed that the peak derived from the vinyl group of the raw material completely disappeared and the peak derived from the target product was detected, and the reaction was terminated. After the reaction was completed, the solvent was distilled off at 100°C and a vacuum degree of 1.3 kPa for 3 hours to obtain a reactive silicon group-containing organopolysiloxane A-3. The obtained reactive silicon group-containing organopolysiloxane A-3 was a colorless transparent liquid, having a number average molecular weight of 15,200 and a viscosity of 620 mPa·s.

[0065] [Example 2-4] Synthesis of organopolysiloxane A-4 containing reactive silicon group Into a 200 mL separable flask equipped with a stirrer, a reflux condenser and a thermometer, 100 g (0.015 mol in terms of vinyl group) of a dimethylpolysiloxane blocked with vinyl dimethylsiloxy groups at both ends with a number average molecular weight of 13,600 and a toluene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (50 ppm in terms of platinum) were added and heated to 60°C. 9.70 g (0.030 mol in terms of hydrosilyl group) of the disiloxane compound c was added thereto and stirred at 60°C for 2 hours. 1 By 1H-NMR measurement, it was confirmed that the peak derived from the vinyl group of the raw material completely disappeared and the peak derived from the target product was detected, and the reaction was terminated. After the reaction was completed, the solvent was distilled off at 100°C and a vacuum degree of 1.3 kPa for 3 hours to obtain a reactive silicon group-containing organopolysiloxane A-4. The obtained reactive silicon group-containing organopolysiloxane A-4 was a colorless transparent liquid, having a number average molecular weight of 15,500 and a viscosity of 620 mPa·s.

[0066] [Comparative Example 2-1] Synthesis of organopolysiloxane A'-5 containing reactive silicon group In a 200 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 100 g (0.015 mol in terms of vinyl groups) of a dimethylpolysiloxane blocked with vinyl dimethylsiloxy groups at both ends having a number average molecular weight of 13,600 and a toluene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (50 ppm as platinum) were placed and heated to 60°C. 3.18 g (0.030 mol in terms of hydrosilyl groups) of methyldimethoxysilane was added thereto, and the mixture was stirred at 60°C for 2 hours. 1 It was confirmed by 1H-NMR measurement that the peak derived from the vinyl group of the raw material completely disappeared and the peak derived from the target product was detected, and the reaction was terminated. After the reaction was completed, the solvent was distilled off at 100°C and 1.3 kPa for 3 hours to obtain a reactive silicon group-containing organopolysiloxane A'-5. The obtained reactive silicon group-containing organopolysiloxane A'-5 was a colorless transparent liquid, having a number average molecular weight of 15,500 and a viscosity of 620 mPa·s.

[0067] [Comparative Example 2-2] Synthesis of organopolysiloxane A'-6 containing reactive silicon group In a 200 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 100 g (0.015 mol in terms of vinyl groups) of a dimethylpolysiloxane blocked with vinyl dimethylsiloxy groups at both ends having a number average molecular weight of 13,600 and 2.54 g (0.015 mol in terms of mercapto groups) of mercaptomethyltrimethoxysilane were placed and heated to 90°C. 0.1 g of 2,2'-azobis-2-methylbutyronitrile was added thereto, and the mixture was stirred at 90°C for 3 hours. 1 It was confirmed by 1H-NMR measurement that the peaks derived from the vinyl group and the mercapto group of the raw material completely disappeared and the peak derived from the target product was detected, and the reaction was terminated. The obtained reactive silicon group-containing organopolysiloxane A'-6 was a colorless transparent liquid, having a number average molecular weight of 15,900 and a viscosity of 550 mPa·s.

[0068] [Comparative Example 2-3] Synthesis of organopolysiloxane A'-7 containing reactive silicon group Into a 200 mL separable flask equipped with a stirrer, a reflux condenser, and a thermometer, 100 g (0.040 mol in terms of hydroxyl groups) of a polypropylene glycol having hydroxyl groups at both ends with a number average molecular weight of 7,600 and 7.1 g (0.040 mol in terms of isocyanato groups) of isocyanatomethyltrimethoxysilane were placed and heated to 80°C. 0.1 g of dioctyltin dilaurate was added thereto, and the mixture was stirred at 80°C for 3 hours. It was confirmed by IR measurement that the absorption peak derived from the isocyanato group of the raw material completely disappeared and the absorption peak derived from the urethane bond was detected, and the reaction was terminated. The obtained reactive silicon group-containing organopolysiloxane A'-7 was a pale yellow transparent liquid, having a number average molecular weight of 8,000 and a viscosity of 3,700 mPa·s.

[0069] [3] Preparation of Composition and Cured Film [Example 3-1] 100 parts by mass of the reactive silicon group-containing organopolysiloxane A-1 obtained in Example 2-1 above and 0.5 part by mass of a curing catalyst B-1 (2-[3-(trimethoxysilyl)propyl]-1,1,3,3-tetramethylguanidine) were uniformly mixed using a stirrer under moisture shielding to prepare a composition. The obtained composition was applied to a glass plate using a bar coater No. 14 under air at 25°C and 50% RH, and dried and cured for 1 day under air at 25°C and 50% RH to prepare a cured film.

[0070] [Examples 3-2 to 3-4 and Comparative Examples 3-1 to 3-3] In Example 3-1, except that the reactive silicon group-containing organopolysiloxane A-1 was changed to the reactive silicon group-containing organopolysiloxanes A-2 to A-4 obtained in Examples 2-2 to 2-4 and the reactive silicon group-containing organopolysiloxanes A'-5 to A'-7 obtained in Comparative Examples 2-1 to 2-3, respectively, a composition and a cured film were prepared in the same manner as in Example 3-1.

[0071] [Example 3-5] In Example 3-1, a composition and a cured film were prepared in the same manner as in Example 3-1, except that the curing catalyst B-1 was changed to 5 parts by mass of curing catalyst B-2 (3-aminopropyltrimethoxysilane).

[0072] [Example 3-6] In Example 3-1, a composition and a cured film were prepared in the same manner as in Example 3-1, except that the curing catalyst B-1 was changed to 5 parts by mass of curing catalyst B-3 (dioctyltin dibutyrate).

[0073] [Example 3-7] In Example 3-1, a composition and a cured film were prepared in the same manner as in Example 3-1, except that the curing catalyst B-1 was changed to 2 parts by mass of curing catalyst B-4 (titanium diisopropoxybis(ethylacetoacetate)).

[0074] [Comparative Example 3-4] In Comparative Example 3-1, a composition and a cured film were prepared in the same manner as in Comparative Example 3-1, except that the curing catalyst B-1 was changed to 5 parts by mass of curing catalyst B-2 (3-aminopropyltrimethoxysilane).

[0075] [Comparative Example 3-5] In Comparative Example 3-1, a composition and a cured film were prepared in the same manner as in Comparative Example 3-1, except that the curing catalyst B-1 was changed to 5 parts by mass of curing catalyst B-3 (dioctyltin dibutyrate).

[0076] [Comparative Example 3-6] In Comparative Example 3-2, a composition and a cured film were prepared in the same manner as in Comparative Example 3-2, except that the curing catalyst B-1 was changed to 5 parts by mass of curing catalyst B-2 (3-aminopropyltrimethoxysilane).

[0077] [Comparative Example 3-7] In Comparative Example 3-2, a composition and a cured film were prepared in the same manner as in Comparative Example 3-2, except that the curing catalyst B-1 was changed to 5 parts by mass of curing catalyst B-3 (dioctyltin dibutyrate).

[0078] For the cured films prepared in Examples 3-1 to 3-7 and Comparative Examples 3-1 to 2-7 above, the following physical properties were evaluated. The results are shown in Tables 1 and 2. 〔Touch-dry time〕 A test piece obtained by applying the composition to a glass plate by the above coating method was left in air at 25°C and 50% RH. As moisture curing progressed, the time until the coating film no longer adhered to the finger when the coated surface was pressed with the finger was measured. A smaller value indicates better curability. 〔Yellowing resistance〕 A test piece with a cured film formed on a glass plate by the above coating method was irradiated with ultraviolet light for 2 weeks (integrated irradiation dose: 26,000 mJ / cm 3 ) using a germicidal lamp in air at 25°C and 50% RH. The degree of yellowing of the cured film at that time was evaluated by ΔYI (degree of yellowing = change width of yellowness YI) using a color difference meter based on JIS K 7373. A smaller value indicates better yellowing resistance. When ΔYI was less than 0.5, it was evaluated as "○" indicating excellent yellowing resistance. When ΔYI was 0.5 or more, it was evaluated as "×". 〔Heat resistance〕 A test piece with a cured film formed on a glass plate by the above coating method was left standing in a dryer at 150°C for 2 weeks. Thereafter, if no fingerprint mark was left on the coating film when the coating film surface was pressed with the finger, it was evaluated as "○". If a fingerprint mark was left on the coating film when the coating film surface was pressed with the finger, it was evaluated as "×".

[0079]

Table 1

[0080]

Table 2

[0081] As shown in Table 1, it can be seen that the cured films prepared in Examples 3-1 to 3-7 using the reactive silicon group-containing organopolysiloxanes A-1 to A-4 obtained in Examples 2-1 to 2-4 are excellent in curability, yellowing resistance, and heat resistance. On the other hand, as shown in Table 2, Comparative Examples 3-1, 3-4, and 3-5 using organopolysiloxane A'-5 having no group represented by the above structural formula (1) were inferior in curability, and Comparative Examples 3-2, 3-6, and 3-7 using organopolysiloxane A'-6 having a sulfide-methylene-silicon bond were low in heat resistance. It can be seen that Comparative Example 3-3 using organopolysiloxane A'-7 having a urethane bond was inferior in yellowing resistance.

Claims

1. A reactive silicon group-containing organopolysiloxane having one or more groups represented by the following structural formula (1) bonded to a silicon atom in one molecule. 【Chemical 1】 (wherein, R 1 and R 2 each independently represents a hydrogen atom, an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, and R 3 each independently represents an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, and n is an integer of 2 to 12. The wavy line represents a bond.)

2. The reactive silicon group-containing organopolysiloxane according to Claim 1, represented by the following formula (2). 【Chemical 2】 (wherein R 1 , R 2 , R 3 and n represent the same meanings as described above, and R 4 each independently represents an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, and p is an integer of 1 to 2,000.)

3. A disiloxane compound represented by the following formula (3). 【Chemical Formula 3】 (wherein R 1 and R 2 are each independently a hydrogen atom, an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, and R 3 are each independently an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms.)

4. A method for producing a reactive silicon group-containing organopolysiloxane according to Claim 1, comprising subjecting an organopolysiloxane containing an alkenyl group bonded to a silicon atom and a disiloxane compound represented by the following formula (3) to a hydrosilylation reaction. 【Chemical 4】 (wherein R 1 , R 2 and R 3 represent the same meaning as described above.)

5. The method for producing a reactive silicon group-containing organopolysiloxane according to Claim 4, wherein the organopolysiloxane containing an alkenyl group bonded to the silicon atom is represented by the following formula (4). 【Chemical Formula 5】 (In the formula, R 4 each independently represents an aliphatic saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, and R 5 represents an alkenyl group having 2 to 12 carbon atoms, and p is an integer of 1 to 2000.)

6. A curable composition containing (A) the reactive silicon group-containing organopolysiloxane according to Claim 1 and (B) a curing catalyst.

7. The curable composition according to Claim 6, wherein the (B) curing catalyst is an amine compound.

8. A cured product obtained by curing the curable composition according to Claim 6 or 7.

9. A coating agent composition containing (A) the reactive silicon group-containing organopolysiloxane according to Claim 1 and (B) a curing catalyst.

10. The coating agent composition according to Claim 9, wherein the (B) curing catalyst is an amine compound.

11. An article having a coating layer obtained by curing the coating agent composition according to Claim 9 or 10.

12. An adhesive composition containing (A) the reactive silicon group-containing organopolysiloxane according to Claim 1 and (B) a curing catalyst.

13. The adhesive composition according to Claim 12, wherein the (B) curing catalyst is an amine compound.

14. An article having an adhesive layer obtained by curing the adhesive composition according to Claim 12 or 13.

Images