Organopolysiloxane containing reactive silicon groups and surface treatment agent

Abstract

An organopolysiloxane containing a reactive silicon group, which contains one group represented by the following structural formula (1) bonded to a silicon atom at the end of a linear organopolysiloxane in one molecule, gives a film excellent in water repellency, water slipperiness, and durability. In the formula, R 1 and R 2 each independently represents a hydrogen atom, an aliphatic saturated hydrocarbon group having a carbon number of 1 to 10, or an aromatic group having a carbon number of 6 to 10, R 3 each independently represents an aliphatic saturated hydrocarbon group having a carbon number of 1 to 10 or an aromatic group having a carbon number of 6 to 10, and Z represents an oxygen atom, an alkylene group having a carbon number of 2 to 12, or an alkylene arylene group having a carbon number of 8 to 12, and the line with a wavy line represents a bonding end.

Description

Technical Field

[0001] The present invention relates to organopolysiloxanes containing reactive silicon groups and surface treatment agents, and more specifically, to organopolysiloxanes having organosilicone groups as reactive silicon groups that can react to form siloxane bonds, and cured products containing the same. Background Technology

[0002] Previously, surface treatment agents that blend fluoroalkyl silanes and amino-modified polysiloxanes were proposed as water-repellent agents for glass (see Patent Documents 1-6).

[0003] While the water-repellent film composed of these surface treatment agents has excellent water repellency, the water droplets on the film surface are not sufficiently repellent. For example, in the case of automotive windows, the repellency needs to be improved to ensure good visibility during rainfall.

[0004] In this regard, as a composition for providing a water-repellent coating that combines water-repellency and hydrophobicity, Patent Document 7 proposes a surface treatment agent comprising a linear organopolysiloxane having a reactive group at one end and an organosilicon compound containing an alkoxy group.

[0005] However, the water-repellent film formed by the surface treatment agent of Patent Document 7 is not durable enough against impact and abrasion, and it is difficult to maintain water repellency.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2012-224668

[0009] Patent Document 2: Japanese Patent Application Publication No. 2009-137775

[0010] Patent Document 3: Japanese Patent Application Publication No. 2009-173491

[0011] Patent Document 4: Japanese Patent Application Publication No. 10-102046

[0012] Patent Document 5: Japanese Patent Application Publication No. 2003-160361

[0013] Patent Document 6: Japanese Patent Application Publication No. 09-176622

[0014] Patent Document 7: Japanese Patent Application Publication No. 11-315276 Summary of the Invention

[0015] The problem that the invention aims to solve

[0016] The present invention was made in view of the above-mentioned actual situation, and its object is to provide an organopolysiloxane containing a reactive silicon group and a surface treatment agent containing the same, which can form a film with excellent water repellency, hydrophobicity and durability.

[0017] Methods for solving problems

[0018] In order to solve the above-mentioned problems, the inventors conducted in-depth research and found that a linear organopolysiloxane with a silane group containing an organic methyl group and two organic oxygen groups at the single end of the molecular chain as a reactive silicon group can provide a coating with excellent water repellency, hydrophobicity and durability, thus completing the present invention.

[0019] That is, the present invention provides:

[0020] 1. An organopolysiloxane containing a reactive silicon group, wherein each molecule contains a group represented by the following structural formula (1) bonded to a silicon atom at the end of a linear organopolysiloxane.

[0021] [Chemistry 1]

[0022]

[0023] In the formula, 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; R 3 Each group independently represents an aliphatic saturated hydrocarbon group with 1 to 10 carbon atoms or an aryl group with 6 to 10 carbon atoms. Z represents an oxygen atom, an alkylene group with 2 to 12 carbon atoms, or an alkylene arylene group with 8 to 12 carbon atoms. The line with a wavy line represents the bonding end.

[0024] 2. The organopolysiloxane containing reactive silicon groups according to claim 1, which is represented by the following formula (2),

[0025] [Chemistry 2]

[0026]

[0027] 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, R 5 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; R 1 R 2 R 3 Z represents the same meaning as above, m represents an integer from 0 to 2, and n is an integer from 1 to 100;

[0028] 3. A surface treatment agent comprising an organopolysiloxane containing a reactive silicon group according to 1 or 2, its hydrolytic condensate, or both;

[0029] 4. The surface treatment agent according to claim 3, further comprising an acid catalyst;

[0030] 5. An article formed by the adhesion of the surface treatment agent according to 3.

[0031] The effects of the invention

[0032] The organopolysiloxane containing reactive silicon groups of the present invention can form a coating with excellent water repellency, hydrophobicity and durability, and is therefore suitable as a surface treatment agent for use in water-repellent treatment of fiber products, glass of conveyors and vehicle bodies. Detailed Implementation

[0033] The present invention will now be described in detail.

[0034] The reactive silicon-containing organopolysiloxane of the present invention is an organopolysiloxane containing a reactive silicon-containing group in one molecule that is bonded to a silicon atom at the end of a linear organopolysiloxane and represented by the following structural formula (1).

[0035] [Chemistry 3]

[0036]

[0037] In equation (1), 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; R 3 Each can independently represent an aliphatic saturated hydrocarbon group with 1 to 10 carbon atoms or an aryl group with 6 to 10 carbon atoms.

[0038] As R 1 R 2 and R 3 It refers to aliphatic saturated hydrocarbon groups with 1 to 10 carbon atoms, which can be straight-chain, cyclic, or branched. Specific examples include straight-chain or branched alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; and cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl.

[0039] As R 1 R 2 and R 3 Specific examples of aryl groups with 6 to 10 carbon atoms include phenyl, tolyl, xylyl, α-naphthyl, β-naphthyl, etc.

[0040] In addition, some or all of the hydrogen atoms in these groups can be replaced by halogen atoms such as F, Cl, Br, or cyano groups. Specific examples include 3-chloropropyl, 3,3,3-trifluoropropyl, and 2-cyanoethyl.

[0041] Among these, as R 1 R 2 and R 3 Methyl, ethyl, and phenyl are preferred, with methyl being more preferred in terms of curability, productivity, and cost.

[0042] In formula (1), the alkylene group having 2 to 12 carbon atoms as Z is preferably an alkylene group having 2 to 8 carbon atoms, and the alkylarylene group having 8 to 12 carbon atoms is preferably an alkylarylene group having 8 to 10 carbon atoms. Specific examples of preferred Z include groups represented by the following structural formulas, but are not limited to these.

[0043] [Chemistry 4]

[0044]

[0045] (In the formula, the line with a wavy line indicates the joint end.)

[0046] The siloxane structural units (M unit, D unit, T unit and Q unit) of the organopolysiloxane containing reactive silicon groups of the present invention are not particularly limited. The siloxane backbone may have a linear structure, a branched structure, a cyclic structure or a cross-linked structure. From the viewpoint of the mechanical properties of the obtained film and the preservation stability of the surface treatment agent, a linear structure is preferred.

[0047] As the organopolysiloxane containing reactive silicon groups of the present invention, the organopolysiloxane represented by the following formula (2) is preferred.

[0048] [Chemistry 5]

[0049]

[0050] (where R) 1 R 2 R 3 (Z represents the same meaning as above.)

[0051] In equation (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 5 Each can independently represent a hydrogen atom, an aliphatic saturated hydrocarbon group with 1 to 10 carbon atoms, or an aryl group with 6 to 10 carbon atoms.

[0052] As R 4 and R 5Aliphatic saturated hydrocarbon groups with 1 to 10 carbon atoms and aryl groups with 6 to 10 carbon atoms can be listed as examples of those related to the above-mentioned R. 1 R 2 and R 3 The same group as the group illustrated herein, wherein methyl, ethyl, and phenyl are preferred, and methyl is more preferred from the perspective of curability, productivity and cost.

[0053] In equation (2), m is an integer from 0 to 2. From the perspective of improving the durability of the coating, 2 is preferred.

[0054] n is an integer from 1 to 100. From the viewpoint of improving the water repellency and hydrophobicity of the coating, an integer from 5 to 50 is preferred. Furthermore, if n exceeds 100, the durability of the resulting coating may sometimes decrease.

[0055] Specific examples of the organopolysiloxanes containing reactive silicon groups of the present invention include the following compounds, but are not limited to these.

[0056] [Chemistry 6]

[0057]

[0058] The organopolysiloxane containing reactive silicon groups, where Z is an oxygen atom in formula (1) above, can be obtained by ring-opening polymerization of cyclic trisiloxane compounds such as hexamethylcyclotrisiloxane in the presence of a five-coordinate silicon catalyst using trimethylsilanol or other triorganosilanol compounds as initiators, followed by end-capping by reacting an organooxysilane represented by formula (6) below.

[0059] In addition, the organopolysiloxane containing a reactive silicon group, in which Z in formula (1) is an alkylene group with 2 to 12 carbon atoms or an alkylene arylene group with 8 to 12 carbon atoms, can be obtained by performing a hydrosilylation reaction between a linear organopolysiloxane containing an alkenyl group at a single end (hereinafter also referred to as "linear organopolysiloxane containing an alkenyl group at a single end") and a disiloxane compound represented by formula (3) in the presence of a platinum group metal catalyst, in the atmosphere or in an inactive gas such as nitrogen.

[0060] As a linear organopolysiloxane containing a single-terminal alkenyl group, a linear organopolysiloxane represented by the following formula (4) is preferred.

[0061] [Chemistry 7]

[0062]

[0063] (where R) 4 R 5 (m and n represent the same meaning as above.)

[0064] In equation (4), R6 It represents an alkenyl group with 2 to 12 carbon atoms or an alkenylaryl group with 8 to 12 carbon atoms.

[0065] As R 6 The alkenyl group having 2 to 12 carbon atoms, preferably an alkenyl group having 2 to 8 carbon atoms, includes vinyl, allyl, 3-butenyl, 5-hexenyl, 7-octenyl, etc. As for alkenyl aryl groups having 8 to 12 carbon atoms, preferably alkenyl aryl groups having 8 to 10 carbon atoms, p-vinylphenyl, p-allylphenyl, etc.

[0066] [Chemistry 8]

[0067]

[0068] (where R) 1 R 2 and R 3 This indicates the same meaning as above.

[0069] As specific examples of disiloxane compounds represented by the above formula (3), examples represented by the following structural formulas can be listed, but are not limited to these. Among these, disiloxane compounds represented by formula (5) are preferred.

[0070] [Chemistry 9]

[0071]

[0072] The disiloxane compound represented by the above formula (3) is obtained, for example, by equilibrating an organooxysilane represented by the following formula (6) with a disiloxane compound represented by the following formula (7) in the presence of acid and water.

[0073] [Chemistry 10]

[0074]

[0075] (where R) 1 R 2 and R 3 This indicates the same meaning as above.

[0076] The reaction ratio of the linear organopolysiloxane containing a single-terminal alkenyl group to the disiloxane compound represented by the above formula (3) is preferably 0.8 to 2.5 of the hydrosilyl group of the disiloxane compound represented by the above formula (3), and more preferably 0.9 to 2.0 of the alkenyl group, relative to 1 alkenyl group in the organopolysiloxane containing an alkenyl group.

[0077] There are no particular limitations on the platinum group metal catalysts used in the above-mentioned hydrosilylation reaction. Specific examples include chloroplatinic acid, alcoholic solutions of chloroplatinic acid, toluene or xylene solutions of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complexes, tetra(triphenylphosphine)platinum, dichlorobis(triphenylphosphine)platinum, dichlorobis(acetonitrile)platinum, dichlorobis(benzonitrile)platinum, dichlorocyclooctadieneplatinum, platinum-carbon, platinum-alumina, platinum-silica, and other supported catalysts.

[0078] Among these, from the perspective of selectivity during hydrosilylation, a platinum complex with zero valence is preferred, and a toluene or xylene solution of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex is more preferred.

[0079] There is no particular limitation on the amount of platinum group metal catalyst used. From the perspective of reactivity and productivity, the preferred amount is 0.1 to 1000 ppm, more preferably 0.3 to 100 ppm, relative to the total mass of the linear organopolysiloxane containing a single-terminal alkenyl group and the disiloxane compound represented by the above formula (3) in terms of the mass conversion of platinum group metals.

[0080] The above-mentioned hydrosilylation reaction can also be carried out in the absence of solvent, or, to the extent that it does not hinder the reaction, a solvent can be used as needed.

[0081] Specific examples of solvents 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; nonprotic polar solvents such as N,N-dimethylformamide; and chlorinated hydrocarbon solvents such as dichloromethane and chloroform. These solvents can be used alone or in combination.

[0082] The reaction temperature in the above-mentioned hydrosilylation reaction is not particularly limited, but 0–200°C is preferred, more preferably 40–110°C, and even more preferably 60–100°C. Furthermore, when using a solvent, the reaction is preferably carried out within the range of 0°C to the boiling point of the solvent. The reaction time is not particularly limited, but is typically about 1–60 hours, preferably 1–24 hours.

[0083] The surface treatment agent of the present invention comprises the above-mentioned organopolysiloxane containing reactive silicon groups, its hydrolysis condensate, or both.

[0084] The surface treatment agent of the present invention can also be used with solvents depending on the application and workability. Specific examples of usable organic solvents include esters such as ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, and isobutyl acetate; hydrocarbons such as hexane, cyclohexane, heptane, octane, decane, dodecane, toluene, and xylene; halogenated hydrocarbons such as dichloromethane, 1,1-dichloroethane, and 1,2-dichloroethane; ketones such as methyl ethyl ketone, 2-pentanone, and methyl isobutyl ketone; ethers such as diethylene glycol monomethyl ether and dipropylene glycol monomethyl ether; and alcohols such as ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and isobutanol. These can be used alone or in combination of two or more.

[0085] The concentration of the reactive silicon-based organopolysiloxane of the present invention contained in the surface treatment agent is not particularly limited, but is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and even more preferably 0.5 to 5.0% by mass, relative to the total surface treatment agent. By such a range, the coating film can be given uniform and excellent water repellency and hydrophobicity.

[0086] In addition, the surface treatment agent of the present invention may contain a hydrolysis catalyst for the purpose of promoting the reaction of the hydrolytic groups of the organopolysiloxane containing reactive silicon groups with water and promoting the generation of silanol groups.

[0087] Specific examples of hydrolysis catalysts include organic acids such as acetic acid, formic acid, methanesulfonic acid, and p-toluenesulfonic acid; and inorganic acids such as hydrochloric acid, nitric acid, and sulfuric acid. These can be used alone or in combination of two or more.

[0088] Among these, methanesulfonic acid, p-toluenesulfonic acid, and sulfuric acid are preferred, with sulfuric acid being particularly preferred.

[0089] The amount of hydrolysis catalyst added is preferably 0.1 to 15.0% by mass relative to the organopolysiloxane containing reactive silicon groups, more preferably 1.0 to 10.0% by mass.

[0090] Furthermore, the surface treatment agent of the present invention may include a curing catalyst.

[0091] Specific examples of solidification catalysts include titanium catalysts such as tetraisopropoxytitanium, tetra-n-butoxytitanium, tetra-2-ethylhexyloxytitanium, and tetraacetylacetonatetitanium; tin catalysts such as dibutyltin dilaurate, dibutyltin diacetate, and dioctyltin diacetate; aluminum catalysts such as aluminum sec-butoxide, aluminum triacetylacetonate, aluminum diacetate, monoacetate, and aluminum triacetate; and zirconium catalysts such as n-propyl zirconate, n-butyl zirconate, zirconium tetraacetylacetonate, zirconium tetraacetylacetonate, zirconium monoacetylacetonate, and zirconium tetraacetylacetonate.

[0092] The amount of curing catalyst added is preferably 0.1 to 15.0% by mass relative to the organopolysiloxane containing reactive silicon groups, and more preferably 1.0 to 10.0% by mass.

[0093] The surface treatment agent of the present invention may further comprise other organosilicon compounds, their hydrolytic condensates, or mixtures thereof, other than the organopolysiloxanes containing reactive silicon groups of the present invention described above, having hydroxyl or hydrolytic groups bonded to Si atoms.

[0094] Examples of hydrolyzable groups include alkoxy groups, halogen atoms, acyloxy groups, and isocyanate groups.

[0095] Specific examples of other organosilicon compounds, as silane compounds having an alkoxysilane group, include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, diphenyldimethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane, trifluoropropyltrimethoxysilane, hexamethyldisilazane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidylsilane, etc. Examples of silane compounds containing halogenated silyl groups include oleoxypropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(triethoxysilylpropyl)tetrasulfide, and 3-isocyanate-propyltriethoxysilane. Other examples of silane compounds with halogenated silyl groups include methyltrichlorosilane, ethyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, and trifluoroethyltrichlorosilane.

[0096] There are no particular limitations on the amount of other organosilicon compounds added, as long as they do not affect the water repellency and hydrophobicity of the resulting cured film. Preferably, it is 20% by mass or less relative to the organopolysiloxane containing reactive silicon groups of the present invention.

[0097] Furthermore, in addition to the components described above, various additives can be added to the surface treatment agent of the present invention.

[0098] As additives, examples include metal oxides, resins, dyes, pigments, ultraviolet absorbers, and antioxidants. Specifically, examples include silica sol, titanium dioxide sol, and alumina sol.

[0099] There is no particular limitation on the amount of additive added, as long as it does not affect the water repellency and hydrophobicity of the resulting cured film. It is preferably 30% by mass or less relative to the organopolysiloxane containing reactive silicon groups of the present invention.

[0100] By applying the surface treatment agent of the present invention described above to a substrate and drying it, a water-repellent film can be formed on the substrate.

[0101] There are no particular limitations on the material and shape of the substrate. Specific examples include: epoxy resin, phenolic resin, polyimide resin, polycarbonate and polycarbonate blends, acrylic resins such as poly(methyl methacrylate), polyethylene terephthalate, polybutylene terephthalate, unsaturated polyester resins, polyamide resin, acrylonitrile-styrene copolymer resin, styrene-acrylonitrile-butadiene copolymer resin, polyvinyl chloride resin, polystyrene resin, blends of polystyrene and polyphenylene ether, cellulose acetate butyrate, polyethylene resin, and other organic resin substrates; metal substrates such as iron plates, copper plates, and steel plates; coating surfaces; glass; ceramics; concrete; stone slabs; fabrics; wood, stone, tiles; inorganic fillers such as (hollow) silica, titanium dioxide, zirconium oxide, and alumina; and glass fiber products such as glass cloth, glass tape, glass mat, and glass paper, mainly made of glass fiber.

[0102] There are no particular limitations on the application method of the surface treatment agent. As specific examples, well-known methods such as spraying, spin coating, dip coating, roller coating, brush coating, bar coating, and flow coating can be appropriately selected. In addition, it is preferable to treat the surface film surface by wiping it with water after applying the surface treatment agent to the substrate.

[0103] The drying method after coating can be either natural drying or heat drying, preferably carried out in a temperature range of 5–150°C, more preferably near room temperature (5–35°C). If the temperature is above 5°C, the reaction rate of the organopolysiloxane containing reactive silicon groups of the present invention increases, thus enabling the acquisition of a sufficiently durable water-repellent film in a short time. If the temperature is below 150°C, the modification and thermal decomposition of the organopolysiloxane containing reactive silicon groups of the present invention can be suppressed.

[0104] There is no particular limitation on the thickness of the water-repellent membrane, but if transparency and mechanical strength of the membrane are taken into account, a thickness of less than 100 nm is preferred.

[0105] In addition, the water-repellent membrane is preferably made of 2 μl water droplets and has a water contact angle of 100° or more, especially 103° or more, and preferably has a roll-off angle of 45° or less, especially 30° or less. Furthermore, the haze value (haze) is preferably 5 or less, more preferably 1 or less, and even more preferably 0.5 or less.

[0106] The surface treatment agent of the present invention can also be directly coated on the surface of a substrate to form a water-repellent film (cured film). Preferably, a base layer formed by the hydrolysis product of a silicon compound having hydrolyzable groups, other than the organopolysiloxane containing reactive silicon groups of the present invention, is present between the substrate surface and the water-repellent film. By providing such a base layer, the bond between the water-repellent film and the substrate becomes stronger, and the durability of the water-repellent film of the present invention is improved.

[0107] As an organosilicon compound for forming a substrate, considering its high hydrolyticity and ability to form a substrate on a substrate at around room temperature (5 to 35°C), an isocyanate-based silane compound represented by the following general formula (8) is preferred.

[0108] [Chemistry 11]

[0109]

[0110] (In the formula, k represents 0 or 1.)

[0111] The water-repellent film formed by the surface treatment agent of the present invention described above is suitable for water-repellent treatment of fiber products, conveyor glass, and vehicle bodies due to its excellent water repellency, hydrophobicity, and durability. In particular, when applied to window glass and reflectors, it can effectively prevent the reduction of visibility caused by water droplets adhering to the surface during rainy weather.

[0112] Example

[0113] The following examples of synthesis, embodiments and comparative examples are listed to illustrate the present invention in more detail, but the present invention is not limited to these embodiments.

[0114] [1] Synthesis of disiloxane compounds

[0115] [Synthetic Example 1] Synthesis of disiloxane compound (5)

[0116] [Chemistry 12]

[0117]

[0118] In a 300 mL detachable flask equipped with a stirrer, reflux condenser, and thermometer, 200 g of trimethoxy(methoxymethyl)silane and 40.4 g of 1,1,3,3-tetramethyldisiloxane were added. 1.2 g of concentrated sulfuric acid (98% by mass) was added dropwise while stirring at 7°C. After the addition was complete, the mixture was stirred at 25°C for 5 hours. Then, 6 g of Kyowo Chemical Industry Co., Ltd. (registered trademark) 500SH was added, and the mixture was stirred for 1 hour. After filtration, the reaction solution was collected and distilled (distillation temperature 90°C, vacuum 17 kPa) to obtain the disiloxane compound (5).

[0119] 1 H-NMR (CDCl3): δ4.46~4.61ppm (s, 1H, -SiH), 3.41~3.34ppm (s, 9H, -Si(OCH3)2, -OCH3), 3.15~3.13ppm (s, 2H, -CH2-), 0.00~0.02ppm (s, 6H, -SiCH3)

[0120] [2] Synthesis of organopolysiloxanes containing reactive silicon groups

[0121] [Example 1-1] Synthesis of organopolysiloxane a containing reactive silicon groups

[0122] In a 2000 mL detachable flask equipped with a stirrer, thermometer, and Jim Roth condenser, 403 g of hexamethylcyclotrisiloxane, 120 g of acetonitrile, and 18 g of trimethylsilanol were placed. While stirring at 60 °C, 0.14 g of the compound represented by the following structural formula (9) was added, and the reaction was carried out at 60 °C for 2 hours. Next, while stirring at 50 °C, 180 g of vinyltrimethoxysilane and 4 g of tert-butylamine were added, and the reaction was carried out for 5 hours. After the reaction was completed, the solvent was distilled off at 120 °C and a vacuum of 1.3 kPa for 3 hours to obtain a linear organopolysiloxane (10) containing a single-terminal alkenyl group.

[0123] [Chemistry 13]

[0124]

[0125] Next, in a 200 mL detachable flask equipped with a stirrer, thermometer, ester adapter, and Jim Roth condenser, 136 g of a linear organopolysiloxane (10) containing a single-terminal alkenyl group and a toluene solution (50 ppm by mass) of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex were added. Then, while stirring at 60 °C, 68.3 g of disiloxane compound (5) was added dropwise, and the reaction was carried out at 60 °C for 3 hours. 1 ¹H-NMR analysis confirmed the complete disappearance of the vinyl peak from the raw material, and the detection of the peak from the target compound marked the end of the reaction. After the reaction, the solvent was distilled off at 100°C and a vacuum of 1.3 kPa for 3 hours to obtain an organopolysiloxane a containing reactive silicon groups.

[0126] [Chemistry 14]

[0127]

[0128] [Examples 1-2] Synthesis of organopolysiloxane b containing reactive silicon groups

[0129] In a 2000 mL detachable flask equipped with a stirrer, thermometer, and Jim Roth condenser, 443 g of hexamethylcyclotrisiloxane, 148 g of acetonitrile, and 20 g of trimethylsilanol were placed. While stirring at 60 °C, 0.16 g of the compound represented by the following structural formula (9) was added, and the reaction was carried out at 60 °C for 2 hours. Next, while stirring at 50 °C, 311 g of 7-octenyltrimethoxysilane and 5 g of tert-butylamine were added, and the reaction was carried out for 5 hours. After the reaction was completed, the solvent was distilled off at 120 °C and a vacuum of 1.3 kPa for 3 hours to obtain a linear organopolysiloxane (11) containing a single-terminal alkenyl group.

[0130] Next, in a 200 mL detachable flask equipped with a stirrer, thermometer, ester adapter, and Jim Roth condenser, 163 g of a linear organopolysiloxane (11) containing a single-terminal alkenyl group and a toluene solution (50 ppm by mass) of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex were added. Then, while stirring at 60 °C, 82.8 g of disiloxane compound (5) was added dropwise, and the reaction was carried out at 60 °C for 3 hours. 1 ¹H-NMR analysis confirmed the complete disappearance of the vinyl peak from the raw material, and the detection of the peak from the target compound marked the end of the reaction. After the reaction, the solvent was distilled off at 100°C and a vacuum of 1.3 kPa for 3 hours to obtain organopolysiloxane b containing reactive silicon groups.

[0131] [Chemistry 15]

[0132]

[0133] [Examples 1-3] Synthesis of organopolysiloxanes C containing reactive silicon groups

[0134] In a 2000 mL detachable flask equipped with a stirrer, thermometer, and Jim Roth condenser, 443 g of hexamethylcyclotrisiloxane, 148 g of acetonitrile, and 20 g of trimethylsilanol were placed. While stirring at 60 °C, 0.16 g of the compound represented by the above structural formula (9) was added, and the reaction was carried out at 60 °C for 2 hours. Next, while stirring at 50 °C, 300 g of p-styrenetrimethoxysilane and 5 g of tert-butylamine were added, and the reaction was carried out for 5 hours. After the reaction was completed, the solvent was distilled off at 120 °C and a vacuum of 1.3 kPa for 3 hours to obtain a linear organopolysiloxane (12) containing a single-terminal alkenyl group.

[0135] Next, in a 200 mL detachable flask equipped with a stirrer, thermometer, ester adapter, and Jim Roth condenser, 157.5 g of a linear organopolysiloxane (12) containing a single-terminal alkenyl group and a toluene solution (50 ppm by mass) of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex were added dropwise while stirring at 60 °C. The reaction was then carried out at 60 °C for 3 hours. 1 ¹H-NMR analysis confirmed the complete disappearance of the vinyl peak from the raw material, and the detection of the peak from the target compound marked the end of the reaction. After the reaction, the solvent was distilled off at 100°C and a vacuum of 1.3 kPa for 3 hours to obtain an organopolysiloxane c containing reactive silicon groups.

[0136] [Chemistry 16]

[0137]

[0138] [Examples 1-4] Synthesis of organopolysiloxanes d containing reactive silicon groups

[0139] In a 2000 mL detachable flask equipped with a stirrer, thermometer, and Jim Roth condenser, 443 g of hexamethylcyclotrisiloxane, 148 g of acetonitrile, and 20 g of trimethylsilanol were placed. While stirring at 60 °C, 0.16 g of the compound represented by the above structural formula (9) was added, and the reaction was carried out at 60 °C for 2 hours. Next, while stirring at 50 °C, 113 g of trimethoxy(methoxymethyl)silane and 5 g of tert-butylamine were added, and the reaction was carried out for 5 hours. After the reaction was completed, the solvent was distilled off at 120 °C and a vacuum of 1.3 kPa for 3 hours to obtain an organopolysiloxane d containing reactive silicon groups.

[0140] [Chemistry 17]

[0141]

[0142] [2] Preparation of surface treatment agents

[0143] [Example 2-1]

[0144] 0.920g of the organopolysiloxane a containing reactive silicon groups obtained in Example 1-1 and 0.080g of 98% sulfuric acid were added to 19.0g of ethyl acetate and mixed to obtain a surface treatment agent.

[0145] [Example 2-2]

[0146] In Example 2-1, the organopolysiloxane a containing reactive silicon groups was replaced with the organopolysiloxane b containing reactive silicon groups obtained in Example 1-2. Otherwise, the same procedure as in Example 2-1 was followed to obtain the surface treatment agent.

[0147] [Examples 2-3]

[0148] In Example 2-1, the organopolysiloxane a containing reactive silicon groups was replaced with the organopolysiloxane c containing reactive silicon groups obtained in Examples 1-3. Otherwise, the same procedure as in Example 2-1 was followed to obtain the surface treatment agent.

[0149] [Examples 2-4]

[0150] In Example 2-1, the organopolysiloxane a containing reactive silicon groups was replaced with the organopolysiloxane d containing reactive silicon groups obtained in Examples 1-4. Otherwise, the same procedure as in Example 2-1 was followed to obtain the surface treatment agent.

[0151] [Comparative Example 2-1]

[0152] In Example 2-1, the linear organopolysiloxane a containing a single-terminal alkenyl group was replaced with an organopolysiloxane e represented by the following formula. Otherwise, the same procedure as in Example 2-1 was followed to obtain the surface treatment agent.

[0153] [Chemistry 18]

[0154]

[0155] The surface treatment agents prepared in Examples 2-1 to 2-4 and Comparative Example 2-1 were soaked in paper towels and used to wipe and coat the glass substrates. After air drying for 1 minute, water was soaked in paper towels and the coated surfaces of the glass substrates were wiped. After air drying at 25°C for 1 hour, glass substrates with a water-repellent film were obtained. The obtained glass substrates with a water-repellent film were used to conduct the evaluation tests (1) to (4) below. The results are shown in Table 1. It should be noted that the water contact angle and the water droplet sliding angle (roll-off angle) were measured using a contact angle meter equipped with a sliding element (Drop MasterDM-701 manufactured by Kyowa Interface Science Co., Ltd.).

[0156] (1) Water repellency

[0157] Two μL of water was dropped onto the treated surface of a glass substrate with a water-repellent film, and the water contact angle was measured.

[0158] (2) Water-skimming properties

[0159] Two μL of water was dropped onto the treated surface of a glass substrate with a water-repellent film, and the roll-off angle was measured.

[0160] (3) Ultrasonic cleaning test

[0161] A glass substrate with a water-repellent film was immersed in an aqueous solution of 1% by mass surfactant (Lipon F, manufactured by Lion Hydraulin Co., Ltd.) and irradiated with ultrasound (100W, 42kHz) for 30 minutes. The water repellency and hydrophobicity of the glass substrate with the water-repellent film after the test were evaluated using the same steps as described in (1) and (2) above.

[0162] (4) Wear test

[0163] Abrasion tests were conducted on the treated surface of the glass substrate with the water-repellent film under the conditions of 2cm×2cm flannel cloth, 1.2kg load, and 1200 cycles. The water repellency and hydrophobicity of the glass substrate with the water-repellent film after the test were evaluated using the same steps as described in (1) and (2) above.

[0164] [Table 1]

[0165]

[0166] ※It will not roll off at 90°.

[0167] As shown in Table 1, it can be seen that the glass substrates with water-repellent films obtained in Examples 2-1 to 2-4 have good water repellency and hydrophobicity in the initial stage, after ultrasonic cleaning test, and after wear test.

[0168] On the other hand, it can be seen that the glass substrate with a water-repellent film obtained in Comparative Example 2-1 showed a significant decrease in hydrophobicity, especially after ultrasonic cleaning and abrasion tests.

Claims

1. An organopolysiloxane containing a reactive silicon group, wherein each molecule contains a group represented by the following structural formula (1) bonded to a silicon atom at the end of a linear organopolysiloxane. [Chemistry 1] In the formula, 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; R 3 Each group independently represents an aliphatic saturated hydrocarbon group with 1 to 10 carbon atoms or an aryl group with 6 to 10 carbon atoms. Z represents an oxygen atom, an alkylene group with 2 to 12 carbon atoms, or an alkylene arylene group with 8 to 12 carbon atoms. The line with a wavy line represents the bonding end.

2. The organopolysiloxane containing reactive silicon groups according to claim 1, which is represented by the following formula (2), [Chemistry 2] 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, R 5 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; R 1 R 2 R 3 Z represents the same meaning as above, m represents an integer from 0 to 2, and n is an integer from 1 to 100.

3. A surface treatment agent comprising an organopolysiloxane containing a reactive silicon group as described in claim 1 or 2, its hydrolysis condensate, or both.

4. The surface treatment agent according to claim 3, further comprising an acid catalyst.

5. The article formed by the adhesion of the surface treatment agent according to claim 3.

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