JP2020114899A - Silanol composition, cured product, adhesive, composite film, and curing method - Google Patents

Abstract

To provide a curable composition that gives a cured product having (A) atomic oxygen durability, (B) inhibition of increased sunlight absorption due to atomic oxygen, ultraviolet rays, and electron rays, (C) inhibition of increased vertical infrared emission due to atomic oxygen, ultraviolet rays, and electron rays, (D) outgas inhibition, (E) surface non-adhesiveness, (F) heat yellowing resistance, (G) adhesion, and (H) transparency, in a balanced manner, and is used for radiation resistance or outer space.SOLUTION: A silanol composition contains a cyclic silanol (A1) represented by the formula (I) and a dehydration condensate (A2) thereof and is used for radiation resistance or outer space (where R independently represents a fluorine atom, an aryl group, a vinyl group, an allyl group, a C1-4 alkyl group or the like, n is an integer of 2-10).SELECTED DRAWING: None

Description

The present invention relates to a silanol composition, a cured product, an adhesive, a composite film, and a curing method.

The low earth orbit (LEO) is an orbit that is widely used for earth observation satellites, space shuttles, and spacecraft such as the International Space Station. It has become clear that the materials exposed to this orbital environment will undergo significant erosion when the space shuttle becomes available for space travel. The main component of the atmosphere in low earth orbit is atomic oxygen, and when a spacecraft flies in low earth orbit, the surface of the part of the spacecraft exposed to the atmosphere contains highly reactive atomic oxygen. It is said to be significantly deteriorated by a collision. In addition to atomic oxygen, it is also reported that active gas species such as oxygen ions and atomic nitrogen are also present in the atmosphere, which affects the deterioration of spacecraft.

To solve this problem, for example, Patent Document 1 discloses a method of improving the resistance to atomic oxygen by applying an insulating film made of a silicone resin film on the surface of a space structural material.

In addition, since spacecraft undergoes severe temperature cycles from low temperature (radiation to outer space) to high temperature (incident of strong sunlight), heat control materials (film, paint, etc.) are used on the outer surface of the spacecraft. There is. For these heat control materials, organic materials such as polyimide are generally used as heat resistant films. However, organic materials have a problem of being colored by ultraviolet rays, and a colored film has a higher solar absorptivity, so that the temperature of the film becomes higher due to irradiation of sunlight, and further thermal deterioration or ultraviolet deterioration accelerated by high temperature is caused. It tends to be easier to proceed. Here, the solar absorptance is an index of the easiness of receiving heat input from sunlight, and represents the easiness of absorbing solar energy.

Patent Document 2 discloses a method of improving the resistance to atomic oxygen by applying an insulating film made of a silicone resin film on a polyimide film. Further, Patent Document 2 discloses that a conventional silicone-based resin has a problem that outgas is generated, and as a countermeasure against this, it is preferable to use a thermosetting resin or an inorganic filler in combination.

Outgas is, in a broad sense, a low molecular weight component released from a material. When the silicone resin film is exposed to atomic oxygen, the volatilized components redeposit on the periphery. Volatile components redeposited on the periphery are, for example, a problem of being adsorbed on the surface of the solar cell panel to reduce the output of the solar cell or reducing the characteristics of optical devices such as sensors and cameras, so-called orbital pollution. Causes a problem called. Further, it is considered that the deposits due to the outgas are colored by the ultraviolet rays and the light transmittance is reduced, which may cause the functional deterioration of the above-mentioned equipment to proceed further. As described above, it is preferable to use a thermosetting resin or an inorganic filler in combination to prevent outgassing, but the combined use may impair the transparency of the cured product. Therefore, the combined use of the thermosetting resin and the inorganic filler lowers the light transmittance and is not sufficient as a measure for preventing the functional deterioration of the functional device.

Patent Document 3 also discloses an inorganic film containing aluminum as an essential component in place of the silicone resin as a method for improving the atomic oxygen resistance of the polyimide film. Such an inorganic film is characterized by being less likely to be deteriorated by ultraviolet rays, but in Example 1 of Patent Document 3, the mass reduction of the composite film in the predetermined atomic oxygen resistance test is 1.264 mg, It is shown that the mass change rate was -3.6%. Thus, the resistance to atomic oxygen is not sufficient. Further, since the formation of the inorganic film requires a very high temperature of 480° C., there is a problem that the use of the inorganic film is limited to the base material which can withstand the high temperature treatment.

Further, in Patent Document 4, in order to further improve the performance, which was not sufficient with the protective materials described in Patent Documents 1 to 3, a polysiloxane containing a silsesquioxane structural unit, that is, a formula A curable composition for outer space characterized by containing a polysiloxane represented by (1) has been proposed.

In formula (1), R ¹ , R ² and R ³ are each independently an alkyl group having 1 to 6 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and (meth)acryloyl. Group, an epoxy group or a monovalent organic group having an oxetanyl group, wherein the alkyl group, aralkyl group, aryl group, (meth)acryloyl group, epoxy group and oxetanyl group are halogen atom, hydroxy group, alkoxy group, aryloxy Group, an aralkyloxy group, and/or an oxy group may be substituted, and at least one of R ¹ , R ² and R ^{3 in} the polysiloxane represented by the formula (1) is (meth) It is a monovalent organic group having an acryloyl group, an epoxy group or an oxetanyl group, w represents a positive number, v, x and y each independently represent 0 or a positive number, R ¹ , R ² and R ³ may be the same or different.

JP-A-5-270500 JP, 2003-113264, A JP 2004-225006 A JP, 2011-42755, A

The curable composition for outer space disclosed in Patent Document 4 is (A) atomic oxygen durability, (B) suppression of increase in sunlight absorption rate by ultraviolet rays, (C) outgas suppression, (D) surface. It is said that the curable composition for outer space is excellent in three or more performances including (A) and (C) among performances (characteristics) of non-adhesiveness and (E) conformability to a cured film.

However, as a space material such as a protective material, it is required to have further excellent performance. When used in outer space materials (for example, protective materials), it is especially required that the properties of the solar light absorption rate increase suppression by electron beam and vertical infrared emissivity increase suppression property, and heat yellowing property are excellent. ing. However, regarding the protective material described in Patent Document 4, these characteristics have not been examined. Further, not only materials for outer space but also materials for radiation resistance are required to be excellent in these performances.

The object of the present invention is (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and an ability to suppress increase in solar light absorption rate by electron beam, (C) atomic oxygen, ultraviolet rays, and vertical by electron beam. A cured product having excellent balance of infrared emissivity increase suppression property, (D) outgas suppression property, (E) surface non-adhesive property, (F) heat yellowing property, (G) adhesive strength, and (H) transparency is obtained. And a curable composition that can be used for radiation resistance or for outer space.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and electron rays from a specific silanol composition Inhibition of increase in light absorption rate, (C) Inhibition of increase in vertical infrared emissivity due to atomic oxygen, ultraviolet rays, and electron beams, (D) Outgas inhibition, (E) Surface non-adhesiveness, (F) Yellowing heat resistance , (G) adhesive strength, and (H) it was found that a cured product excellent in transparency can be obtained, and the present invention has been completed.

That is, the present invention is as follows.
[1]
A silanol composition containing a cyclic silanol represented by the following formula (1) (A1) and a dehydration condensation product (A2) thereof, which is used for radiation resistance or for outer space.
(In the formula (I), each R is independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a fluorine-substituted linear or branched alkyl group having 1 to 4 carbon atoms, or It is a substituted linear or branched alkyl group having 1 to 4 carbon atoms, and n is an integer of 2 to 10.)
[2]
The silanol composition according to [1], wherein the cyclic silanol (A1) is represented by the following formula (1).
(In the formula (1), R ^{1 to} R ⁴ are each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, or a fluorine-substituted linear or branched alkyl group having 1 to 4 carbon atoms. Or a non-substituted linear or branched alkyl group having 1 to 4 carbon atoms.)
[3]
The cyclic silanol (A1) is a cyclic silanol (B1) to (B4) represented by the following formulas (2) to (5):
(In formulas (2) to (5), R ^{1 to} R ⁴ are each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, or a linear or branched C ¹ having a fluorine atom. To 4 or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms.)
Containing
When the ratio (mol %) of the cyclic silanol (B2) to the total amount of the cyclic silanols (B1) to (B4) is b, 0<b≦20 is satisfied,
The silanol composition according to [1] or [2].
[4]
In the measurement of gel permeation chromatography, the area of the dehydrated condensate (A2) is more than 0% and 50% or less with respect to the total area of the cyclic silanol (A1) and the dehydrated condensate (A2),
The silanol composition according to any one of [1] to [3].
[5]
The proportion of transition metal is less than 1 mass ppm,
The silanol composition according to any one of [1] to [4].
[6]
Including solvent,
The silanol composition according to any one of [1] to [5].
[7]
Including silica particles having an average particle size of 1 nm or more and 100 nm or less,
The silanol composition according to any one of [1] to [6].
[8]
Including a silanol-modified siloxane having both terminals represented by the following formula (6):
The silanol composition according to any one of [1] to [7].
(In the formula (6), R′ is each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched C 1 -C 4 alkyl group substituted with fluorine, Alternatively, it is an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 0 to 1000.)
[9]
The total content of Na and V is less than 60 mass ppm,
The silanol composition according to any one of [1] to [8].
[10]
A cured product of the silanol composition according to any one of [1] to [9], which is used for radiation resistance or outer space.
[11]
An adhesive which comprises the silanol composition according to any one of [1] to [9] and is used for radiation resistance or space use.
[12]
A film,
A cured product arranged on the film,
And a composite film used for radiation resistance or space use,
The composite film, wherein the cured product is the cured product according to [10].
[13]
A curing method for thermally curing the silanol composition according to any one of [1] to [9], comprising:
A curing method in which the curing temperature is 60 to 250°C.
[14]
The curing method according to [13], wherein the curing time is 10 minutes to 72 hours.

According to the present invention, (A) Atomic oxygen durability, (B) Atomic oxygen, ultraviolet rays, and suppression of increase in solar light absorption rate by electron beams, (C) Vertical by oxygen atoms, ultraviolet rays, and electron beams. To obtain a cured product having excellent infrared emissivity increase suppression property, (D) outgas suppression property, (E) surface non-adhesive property, (F) heat yellowing, (G) adhesive strength, and (H) transparency. The silanol composition which can do this can be provided.

FIG. 3 is a diagram showing a ¹ H-NMR spectrum used when calculating a stereoisomer ratio of a silanol composition obtained in Example 10. FIG. 6 is a diagram showing a ¹ H-NMR spectrum used in calculating a stereoisomer ratio of the silanol composition obtained in Example 16.

Hereinafter, modes for carrying out the present invention (hereinafter, also referred to as “the present embodiment”) will be described in detail. It should be noted that the present invention is not limited to this embodiment, and various modifications can be carried out within the scope of the gist thereof.

(Silanol composition)
The silanol composition of the present embodiment contains a cyclic silanol (A1) represented by the formula (I) and a dehydration condensate (A2) of the cyclic silanol (A1) represented by the formula (I). Used for space or space. In the present specification, the “silanol composition” of the present embodiment is also referred to as “curable composition”.

In formula (I), each R is independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or an unsubstituted group. Is a linear or branched alkyl group having 1 to 4 carbon atoms, and n is an integer of 2 to 10.

The "outer space" in the present embodiment is a concept including all low earth orbits (altitude from the surface of the earth to 2000 km or less, preferably 100 km to 1000 km), and spaces far from the low earth orbit. The "outer space" is a concept that includes a hygienic space such as the moon and a space inside the satellite, and a space on a planet such as Venus and Mars and a space inside the planet. Furthermore, the "space" is a concept including the inside of a spacecraft existing in the space (for example, an earth observation satellite, a space shuttle, an international space station, etc.).

Further, the "outer space" in the present embodiment means a space in which atomic oxygen exists. Further, active gas such as oxygen ions or atomic nitrogen may or may not be present in this outer space. Then, the silanol composition of the present embodiment is suitably used as a material for a space mechanism product (for example, a component of a spacecraft) exposed to such space. Therefore, the silanol composition of this embodiment can also be called a silanol composition for outer space. However, the silanol composition of the present embodiment is not limited to the one for outer space, and as will be described later, the silanol composition of the present embodiment is also used for radiation resistance.

The silanol composition of this embodiment can be used, for example, as a component of a spacecraft. The silanol composition is, for example, a heat control material, a heat insulating film, a sheet, a woven fabric, a paint, a solar reflective material, a heat conductive adhesive, a thermal filler, a structural panel (for example, a composite material), a truss, a tether (for example, String, etc.), debris bumper (for example, a plate or cushion material for protecting spacecraft from space debris), solar battery paddle (for example, solar cell protective cover, etc.), electric wire, insulating coating, heater, antenna constituent material, It is used for cameras, monitors, lights and their protective covers (for example, radio wave transmission radomes, etc.), robot arms, etc.

Further, the silanol composition of the present embodiment, the outer skin of the space suit in general, the heat insulation tile and window material of the space shuttle, the building in the moon and planetary space station or spacecraft, spacecraft and exploration satellites, large deployment structure, Space inflatable structures or solar sails (eg, solar sailboats, large structures using photon pressure propulsion) films, sheets, fabrics, foams and shape memory materials, space elevator cables and elevator enclosures, end-of-life space It is used for films, sheets, foams, etc. of deployable products for de-orbiting machines (for example, de-orbit utilizing increased air resistance).

Further, the silanol composition of the present embodiment is used for protecting the surface of a material for prevention of damage, deterioration (moisture absorption, oxidation, etc.) and pollution at the time of handling on earth, launch or space operation when used for the above applications. Is also used.

Further, the silanol composition of the present embodiment has excellent resistance to radiation such as electron beams as described above. Therefore, the silanol composition of the present embodiment can be used as a radiation resistant material such as an electron beam.

The silanol composition of the present embodiment is also used as a radiation resistant material, that is, a radiation resistant material, and can also be referred to as a radiation resistant silanol composition. The "radiation resistant material" referred to here is a material that is required to have resistance to radiation (eg, alpha rays, beta rays, neutron rays, proton rays, heavy ion rays, meson rays, gamma rays, X rays, electron rays). Say.

The radiation resistant silanol composition of the present embodiment is used in a fast breeder reactor, a nuclear power plant, a radiation irradiation facility, a nuclear fuel disposal work, a decommissioning work, a uranium enrichment facility, a radioactive waste treatment facility, a spent fuel reprocessing facility, etc. , A material used for objects exposed to radiation such as electron beams.

The radiation resistant silanol composition of the present embodiment is, for example, a fast breeder reactor, a nuclear power plant, a radiation irradiation facility, a nuclear fuel disposal operation, a decommissioning operation, a uranium enrichment facility, a radioactive waste treatment facility, a spent fuel reprocessing facility. When exposed to a large dose level radiation environment such as, etc., a film, a sheet, a woven fabric, a foaming agent, etc. for protecting the device, electronic substrate, semiconductor, resin, metal, inorganic substance, organic substance, polymer, etc. from the radiation Used for shape memory materials, adhesives, etc.

The silanol composition of this embodiment can also be called a curable composition. The cured product obtained from the silanol composition is (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and the ability to suppress increase in solar light absorption rate by electron beam, (C) atomic oxygen, ultraviolet rays, and It is excellent in vertical infrared emissivity increase suppression by electron beam, (D) outgas suppression, (E) surface non-adhesiveness, (F) heat yellowing, (G) adhesive strength, and (H) transparency.

The silanol composition of the present embodiment is excellent in heat yellowing, which is a characteristic not found in conventional curable compositions for outer space. The reason why the silanol composition of the present embodiment is excellent in heat-resistant yellowing is considered as follows, but the factor is not limited to this. That is, in the conventional curable composition for outer space, it is necessary to add a component such as a cationic polymerization initiator or a radical polymerization initiator for curing. Further, in the conventional curable composition for outer space, it is necessary for the polysiloxane contained in the curable composition to contain (introduce) a polymerizable group for curing. Due to these, the conventional curable composition for outer space tends to be inferior in yellowing due to heat. On the other hand, the silanol composition of the present embodiment, the cyclic silanol contained in the silanol composition has a specific structure, so that a polymerizable group is introduced, a cationic polymerization initiator or a radical polymerization initiator, etc. It can be fully cured with or without. Therefore, it is considered that the silanol composition of the present embodiment is excellent in heat-resistant yellowing.

In the formula (I), R is independently a fluorine-substituted linear or branched carbon number from the viewpoint of imparting heat-resistant yellowing to the cured product of the silanol composition at higher temperatures. It is preferably an alkyl group having 1 to 4 or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms Is more preferable, and a methyl group is further preferable. Specific examples of the linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine and the unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms will be described later.

In formula (I), n is preferably 2 to 5, more preferably 2 to 4, and even more preferably 3. Since n is 2 to 5, the flexibility and rigidity of the main chain skeleton are excellent, and (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and solar absorptivity due to electron beams. Increase inhibition, (C) atomic oxygen, ultraviolet rays, and vertical infrared emissivity increase inhibition by electron beams, (D) outgas inhibition, (E) surface non-adhesiveness, (F) heat-resistant yellowing, (G) ) The adhesive strength and (H) transparency tend to be more excellent.

The cyclic silanol (A1) contained in the silanol composition of the present embodiment preferably contains the cyclic silanol represented by the formula (1). By containing the cyclic silanol represented by the formula (1), the silanol composition has (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and an ability to suppress increase in solar absorptivity by electron beams, (C) Inhibition of vertical infrared emissivity increase by atomic oxygen, ultraviolet rays, and electron beams, (D) Outgas inhibition, (E) Surface non-adhesiveness, (F) Heat yellowing, (G) Adhesive strength, In addition, (H) tends to be more excellent in transparency.

In formula (1), R ^{1 to} R ⁴ are each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, or a linear or branched C ¹ -C 4 alkyl group substituted with fluorine. Or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms.

Examples of the aryl group include a phenyl group and a naphthyl group. Examples of the linear or branched C1-C4 alkyl substituted with fluorine include the following groups.
CF ₃ −,
CF ₃ CF ₂ −,
CF ₃ CF ₂ CF ₂ -,
(CF _{3) 2} CF-,
CF ₃ CF ₂ CF ₂ CF ₂ −,
HCF ₂ CF ₂ CF ₂ CF ₂ −,
(CF _{3) 2} CFCF ₂ -

Examples of the unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl and the like.

R ^{1 to} R ⁴ in the present embodiment each independently represent a fluorine-substituted linear or branched linear group from the viewpoint of imparting heat-resistant yellowing to the cured product of the silanol composition at a higher temperature. It is preferably an alkyl group having 1 to 4 carbon atoms, or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms. An alkyl group is more preferable, and a methyl group is further preferable.

The silanol composition of the present embodiment preferably has a haze of 10% or less, more preferably 5% or less, and further preferably 2% or less (preferably 1%). When the haze of the silanol composition is 10% or less, the silanol composition has excellent transparency and adhesive strength of the cured product. In addition, since the haze of the silanol composition is 10% or less, the silanol composition has (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and an ability to suppress increase in solar absorptivity due to electron beams. , (C) Atomic oxygen, ultraviolet rays, and vertical infrared emissivity inhibition by electron beam, (D) Outgas inhibition, (E) Surface non-adhesiveness, (F) Heat yellowing, (G) Adhesive strength , And (H) tend to be more excellent in transparency. The haze referred to here is the haze when the silanol composition is dried by the method of Examples described later to give a film thickness of 3 μm.

As a method for reducing the haze of the silanol composition to 10% or less, for example, the proportion of isomers in the cyclic silanol (A1) represented by the formula (I) is adjusted to reduce the proportion of isomers having high crystallinity. Examples include a method and a method for suppressing the amount of metal contained in the composition.

The haze of the silanol composition can be specifically measured by the method described in Examples.

The silanol composition of the present embodiment contains a dehydrated condensate of cyclic silanol represented by the formula (I). The dehydrated condensate of cyclic silanol represented by the formula (I) means that at least one silanol group contained in the cyclic silanol represented by the formula (I) is another cyclic group represented by the formula (I). It is a compound obtained by a reaction of forming a siloxane bond by dehydration condensation with at least one silanol group in a silanol molecule.

For example, when the cyclic silanol represented by the formula (I) is the cyclic silanol represented by the formula (1), the dehydrated condensate of the cyclic silanol represented by the formula (1) is schematically represented by the following formula ( It can be represented by 7).

In formula (7), four R's are each independently one of R ^{1 to} R ⁴ in formula (1), and are a straight chain substituted with a fluorine atom, an aryl group, a vinyl group, an allyl group, or a fluorine atom. Or branched alkyl having 1 to 4 carbon atoms or unsubstituted linear or branched alkyl having 1 to 4 carbon atoms, and m is an integer of 2 or more. The silanol group that undergoes dehydration condensation in the cyclic silanol may be any silanol group. At this time, in the dehydration condensate represented by the formula (7), two or more siloxane bonds may be formed between two or more molecules of the cyclic silanol structure. Moreover, as the preferable group of R in the formula (7), the same preferable groups as the R ^{1 to} R ⁴ groups can be mentioned.

Specific examples of the dehydrated condensate of the cyclic silanol represented by the formula (1) include the following compounds. However, the dehydrated condensate of the cyclic silanol represented by the formula (1) is not limited to the following compounds.

The orientations of the hydroxy group (-OH) and the R group with respect to the cyclic silanol skeleton in the following compounds are not particularly limited. Further, R in the following compounds is each independently one of R ^{1 to} R ⁴ in the formula (1). Furthermore, as the preferable groups of R in the following compounds, the same preferable groups as the R ^{1 to} R ⁴ groups can be mentioned.

In the dehydrated condensate of the cyclic silanol represented by the formula (1), the molecular weight calculated by gel permeation chromatography is preferably 500 to 1,000,000, more preferably 500 to 100,000. Yes, and more preferably 500-10,000.

In the silanol composition of the present embodiment, in the measurement of gel permeation chromatography, the area of the dehydrated condensate (A2) is relative to the total area of the cyclic silanol (A1) and the dehydrated condensate (A2), It is preferably more than 0% and 50% or less. The area of each compound obtained by the measurement of gel permeation chromatography represents the content of each compound in the silanol composition.

When the area of A2 is within the above range, an increase in viscosity can be suppressed when producing the silanol composition. When the area of A2 is within the above range, when the silanol composition contains an organic solvent or water, the organic solvent or water tends to be easily removed from the silanol composition.

The area of A2 is more preferably more than 0% and 40% or less, still more preferably more than 0% and 25% or less.

The area of A2, that is, the content of A2 can be controlled, for example, by purification after the oxidation reaction when a hydrosilane compound is oxidized to obtain a cyclic silanol in the production of a silanol composition.

The area of A1 and A2, that is, the content of A1 and A2 by gel permeation chromatography can be specifically measured by the method described in Examples.

The silanol composition of this embodiment can be prepared by, for example, oxidizing a hydrosilane compound in the presence of water or alcohol. As the hydrosilane compound, any tetra-substituted tetracyclosiloxane containing hydrogen can be used, and a commercially available product can be used.

The hydrosilane compound is preferably a tetra-substituted tetracyclosiloxane represented by the following formula (8).

Wherein (8), R ¹ to R ⁴ are the same as R ¹ to R ⁴ in Formula (1), each independently, a fluorine atom, an aryl group, a vinyl group, an allyl group, substituted by fluorine It is a linear or branched alkyl group having 1 to 4 carbon atoms, or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms.

Specific examples of the cyclic hydrosilane include tetramethyltetracyclosiloxane and the like.

Generally, the cyclic hydrosilanes have no hydroxy or alkoxy functional groups, but such functional groups may be included in a certain amount prior to the oxidation reaction.

Examples of the method of oxidizing the hydrosilane compound include a method of using a catalyst and/or an oxidizing agent.

As the catalyst, for example, a metal catalyst such as Pd, Pt and Rh can be used. These metal catalysts may be used alone or in combination of two or more. Further, these metal catalysts may be supported on a carrier such as carbon.

As the oxidant, for example, peroxides and the like can be used. Any of the peroxides can be used, and examples thereof include oxiranes such as dimethyldioxirane.

As a method of oxidizing the hydrosilane compound, a method of oxidizing the hydrosilane compound using Pd/carbon is preferable from the viewpoint of excellent reactivity and easy removal of the catalyst after the reaction.

The cyclic silanol prepared by oxidizing a hydrosilane compound in the presence of water or alcohol contains various isomers derived from cis and trans of the hydrogen atom of the starting SiH group because of its cyclic structure.

The cyclic hydrosilane compound represented by the above formula (8) is obtained by hydrolysis of chlorosilane or equilibrium polymerization reaction of polymethylsiloxane, but it is difficult to control the ratio of cis and trans isomers. Therefore, various cis and trans isomers are mixed in the cyclic hydrosilane compound. The cis and trans of the cyclic hydrosilane compound in the present embodiment mean that two adjacent hydroxy groups or two adjacent R groups have the same orientation with respect to the cyclic siloxane skeleton (cis), and two adjacent hydroxy groups. Alternatively, two adjacent R groups have different orientations with respect to the cyclic siloxane skeleton (trans).

Examples of the isomers contained in the cyclic silanol produced by the above-mentioned oxidation reaction include all-cis type cyclic silanol (B1) represented by the following formula (2). In the all-cis type cyclic silanol (B1), all the hydroxy groups and the R ^{1 to} R ⁴ groups are respectively arranged in the same direction with respect to the cyclic siloxane skeleton, as shown by the formula (2).

In formula (2), R ^{1 to} R ⁴ are each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched C ¹ -C 4 alkyl substituted with fluorine, Alternatively, it is an unsubstituted linear or branched alkyl having 1 to 4 carbon atoms.

With the all-cis type cyclic silanol (B1) represented by the formula (2), the cyclic silanol synthesized from the cyclic hydrosilane compound by the oxidation reaction tends to become cloudy. This phenomenon is considered to be due to the crystallinity of the all-cis type cyclic silanol (B1), and is particularly remarkable during storage or when frozen at −30° C. By removing the highly crystalline cyclic silanol, it is possible to prevent the silanol from crystallizing and precipitating in the silanol composition, a highly transparent silanol composition is obtained, and a highly transparent cured product can also be obtained. it can. Further, by removing the cyclic silanol having high crystallinity, the adhesive force of the silanol composition is improved.

From the viewpoint of obtaining a silanol composition having further excellent transparency, it is preferable to keep the ratio of the cyclic silanol (B1) small.

Examples of the method for suppressing the proportion of the cyclic silanol (B1) include a method in which a recrystallization operation and a crystal removal are combined.

More specifically, by adding a poor solvent to a good solvent solution of the product obtained by the synthesis of cyclic silanol, cyclic silanol (B1) is precipitated as crystals. By removing the precipitated cyclic silanol (B1) and concentrating the solution in the soluble portion, the ratio of the cyclic silanol (B1) in the silanol composition can be suppressed and a highly transparent silanol composition can be obtained.

When performing the recrystallization operation, the cooling temperature is preferably lower than 10° C. from the viewpoint of obtaining a silanol composition having further excellent transparency. From the viewpoint of improving the yield of cyclic silanol, the amount (volume) of the poor solvent is preferably equal to or more than 20 times the equivalent amount of the good solvent.

The good solvent is not particularly limited, and examples thereof include tetrahydrofuran, diethyl ether, acetone, methanol, ethanol, isopropanol, dimethylformamide, dimethyl sulfoxide, glycerin, ethylene glycol, methyl ethyl ketone and the like. These good solvents may be used alone or in combination of two or more.

The poor solvent is not particularly limited, and examples thereof include toluene, chloroform, hexane, dichloromethane, xylene and the like. These poor solvents may be used alone or in combination of two or more.

Ratio of cyclic silanol (B1) is a cyclic silanol obtained by synthesis can be calculated from measuring ¹ H-NMR. Specifically, in the ¹ H-NMR measurement, hydrogen contained in R ¹ to R ⁴ radicals having cyclic silanol (B1) is a hydrogen R ¹ to R ⁴ radicals having other isomers of cyclic silanol On the other hand, it is observed at the highest magnetic field side. Therefore, the ratio of cyclic silanol (B1) is calculated from the integrated value of these hydrogens.

When a metal catalyst is used for the oxidation of the hydrosilane compound, the recrystallization operation described above causes the transition metal contained in the metal catalyst to remain in the insoluble residue. The proportion of metal can be reduced. Therefore, by the operation for removing the cyclic silanol represented by the formula (2), it is possible to reduce the coloring of the silanol due to the residual metal catalyst.

From the viewpoint of further excellent light transmittance of the silanol composition, the proportion of the transition metal is preferably less than 1 mass ppm with respect to the total mass of the silanol composition.

The proportion of transition metal can be specifically measured by the method described in Examples.

The transition metal is not particularly limited, and examples thereof include palladium.

The cyclic silanol (A1) preferably contains the cyclic silanols (B1) to (B4) represented by the following formulas (2) to (5). In particular, when a tetrasubstituted tetracyclosiloxane represented by the formula (8) is used as a hydrosilane compound as a raw material and is oxidized, the obtained tetrahydroxytetrasubstituted tetracyclosiloxane is represented by the following formulas (2) to (5). The represented cyclic silanols (B1) to (B4) may be mixed, and preferably composed of the cyclic silanols (B1) to (B4). As a result, (H) the cured product is excellent in transparency, (G) the cured product is also excellent in adhesive strength, and (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and the sun by an electron beam are used. Inhibition of increase in light absorption rate, (C) Inhibition of increase in vertical infrared emissivity by atomic oxygen, ultraviolet rays, and electron beams, (D) Outgas inhibition, (E) Surface non-adhesiveness, and (F) Yellow heat resistant It tends to be more excellent in denaturation.

In formulas (2) to (5), R ^{1 to} R ⁴ each independently represent a fluorine atom, an aryl group, a vinyl group, an allyl group, or a linear or branched C ^{1 to} C ¹ substituted with fluorine. 4 alkyl group, or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms.

The preferred groups for R ^{1 to} R ⁴ in formulas (2) to (5) are the same as the preferred groups for R ^{1 to} R ⁴ in formula (1).

The cyclic silanol (A1) in the present embodiment contains the cyclic silanols (B1) to (B4) represented by the formulas (2) to (5), with respect to the total amount of the cyclic silanols (B1) to (B4). When the ratio (mol %) of the cyclic silanol (B2) is b, 0<b≦20 is preferably satisfied. As a result, (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet rays, and suppression of increase in solar light absorption rate by electron beams, (C) atomic oxygen, ultraviolet rays, and vertical infrared radiation by electron beams The rate increase inhibition, (D) outgas inhibition, (E) surface non-adhesiveness, and (F) heat yellowing tend to be more excellent.

As a method of setting the ratio b to 0<b≦20, as described above, for example, a method of combining a recrystallization operation and removal of crystals can be mentioned.

When tetramethyltetracyclosiloxane is used as a raw material for the hydrosilane compound and is oxidized, when ⁶ H-NMR of the resulting tetrahydroxytetramethyltetracyclosiloxane is measured, 6 types of peaks of 4 types of isomers are observed. (Here, three types of peaks are observed for trans-trans-cis). Hydrogen in R ^{1 to} R ⁴ is all-cis (cyclic silanol (B1)), trans-trans-cis (cyclic silanol (B3)), and trans-trans-cis (cyclic silanol (B3)) from the high magnetic field side. ), cis-trans-cis (cyclic silanol (B2)), all-trans (cyclic silanol (B4)), trans-trans-cis (cyclic silanol (B3)) type are observed in this order, so the integration of such hydrogen From the values, the respective proportions of the cyclic silanols (B1) to (B4) are calculated.

Since the cyclic silanol (B2) represented by the formula (3) also has crystallinity, when a good solvent is used in the reaction solution, it is precipitated as a crystal by adding a poor solvent. Due to the cyclic silanol (B2), the synthesized cyclic silanol (A1) tends to become cloudy. This phenomenon is considered to be due to the crystallinity of the cis-trans-cis type cyclic silanol (B2), and is particularly remarkable during storage and when frozen at −30° C.

From the viewpoint of obtaining a silanol composition having further excellent transparency, the ratio of the cyclic silanol (B2) is preferably 0% to 50%, more preferably 0, relative to the cyclic silanol represented by the formula (1). % To 40%, more preferably 0 to 35%, and particularly 0% or more and less than 35%.

As described above, the silanol composition of the present embodiment is a good solvent solution of a product obtained by preparing a cyclic silanol by oxidizing a hydrosilane compound in the presence of water or an alcohol and synthesizing the cyclic silanol. It is preferably produced by subjecting the solution of the soluble portion obtained by filtration to recrystallization and filtration by adding a poor solvent to the solution and concentrating the solution.

In the production of the silanol composition of the present embodiment, the solution of the soluble part may be optionally concentrated, and the solution of the soluble part itself may be used as the silanol composition. Moreover, since it is not necessary to remove all the solvent contained in the solution in the concentration of the solution in the soluble part, the silanol composition of the present embodiment distills off part of the solvent contained in the solution in the soluble part. It may be a crude concentrate obtained by. Furthermore, the silanol composition of the present embodiment may be obtained by concentrating the solution of the soluble part and then re-diluting it with a solvent. As described above, one of the preferable aspects of the present embodiment is a silanol composition containing a solvent.

In this case, the amount of the solvent contained in the silanol composition is preferably 95% by mass or less, more preferably 90% by mass or less, and further preferably 85% by mass or less, based on the total amount of the silanol composition. The lower limit of the amount of solvent is not particularly limited and is, for example, 1% by mass or more.

Examples of the solvent in the silanol composition containing the solvent include water and/or alcohol used in the reaction, a good solvent and a poor solvent used in recrystallization, and the like. The solvent is not particularly limited, for example, water, tetrahydrofuran, diethyl ether, acetone, methanol, ethanol, isopropanol, dimethylformamide, dimethylsulfoxide, glycerin, ethylene glycol, methyl ethyl ketone, toluene, chloroform, hexane, dichloromethane, xylene and the like. Can be mentioned. These solvents may be used alone or in combination of two or more.

The silanol composition of the present embodiment preferably further contains silica particles having an average particle diameter of 1 nm or more and 100 nm or less.

When the average particle size of the silica particles is 1 nm or more, the abrasion resistance tends to be excellent. Moreover, when the average particle diameter of the silica particles is 100 nm or less, the transparent dispersibility tends to be excellent.

The average particle diameter of the silica particles is preferably 1 nm or more and 50 nm or less, more preferably 2 nm or more and 30 nm or less, and further preferably 5 nm or more and 20 nm or less.

The average particle size of silica particles can be measured by dynamic light scattering measurement.

The silica particles having an average particle size of 1 nm or more and 100 nm or less are not particularly limited in form as long as the transparency of the silanol composition of the present embodiment can be maintained. The silica particles are not particularly limited, and examples thereof include a usual aqueous dispersion form and a form dispersed in an organic solvent. Among these, the silica particles are preferably colloidal silica dispersed in an organic solvent, from the viewpoint of being uniformly and stably dispersed in the silanol composition.

The organic solvent in which the silica particles are dispersed is not particularly limited, and examples thereof include methanol, isopropyl alcohol, n-butanol, ethylene glycol, xylene/butanol, ethyl cellosolve, butyl cellosolve, dimethylformamide, dimethylacetamide, methyl ethyl ketone, methyl isobutyl ketone and the like. Are listed.

Among these, the organic solvent is preferably an organic solvent capable of dissolving the silanol composition, from the viewpoint of uniformly dispersing the silica particles in the silanol composition.

The colloidal silica dispersed in an organic solvent is not particularly limited, and examples thereof include methanol silica sol MA-ST, isopropyl alcohol silica sol IPA-ST, n-butanol silica sol NBA-ST, ethylene glycol silica sol EG-ST, xylene/ Butanol silica sol XBA-ST, ethyl cellosolve silica sol ETC-ST, butyl cellosolve silica sol BTC-ST, dimethylformamide silica sol DBF-ST, dimethylacetamide silica sol DMAC-ST, methyl ethyl ketone silica sol MEK-ST, methyl isobutyl ketone silica sol MIBK-ST (above, product Name, manufactured by Nissan Chemical Co., Ltd.) and the like.

When the silanol composition of the present embodiment further contains silica particles having an average particle size of 1 nm or more and 100 nm or less, the silanol composition can be suitably produced as follows. That is, a cyclic silanol is prepared by oxidizing a hydrosilane compound in the presence of water or alcohol. Next, a poor solvent is added to a good solvent solution containing the product obtained by the synthesis of cyclic silanol to perform recrystallization and filtration. Next, the solution of the soluble portion obtained by filtration is concentrated, and silica particles having an average particle diameter of 1 nm or more and 100 nm or less or the silica particle dispersion liquid is added.

The content of the silica particles in the silanol composition of the present embodiment is preferably 10 to 80% by mass, more preferably 20 to 70% by mass, based on the total amount of solids in the silanol composition. More preferably, it is 30 to 60 mass %.

When the content of the silica particles is 10% by mass or more, the cured product tends to have excellent wear resistance. When the content of the silica particles is 80% by mass or less, the cured product tends to have excellent transparency.

Here, the total amount of solids in the silanol composition is, for example, the total amount of the cyclic silanol (A1) and the silica particles.

The silanol composition of the present embodiment preferably further contains a silanol-modified siloxane modified at both ends represented by the following formula (6). As a result, the transparency of the (H) cured product and the adhesive strength of the (G) cured product are further excellent, and (A) atomic oxygen durability, (B) atomic oxygen, ultraviolet light, and solar light absorption by an electron beam. Rate increase inhibition, (C) atomic oxygen, ultraviolet rays, and vertical infrared emissivity inhibition by electron beams, (D) outgas inhibition, (E) surface non-adhesiveness, and (F) heat yellowing It tends to be even better.

In formula (6), R′ is each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with fluorine, or Is an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 0 to 1000.

In the formula (6), R′ is preferably an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, more preferably an unsubstituted C 1 carbon atom from the viewpoint of suppressing thermal decomposition. To 2 alkyl groups, more preferably unsubstituted methyl groups.

From the viewpoint of compatibility with the cyclic silanol (A1), the molecular weight of the both-end silanol-modified siloxane represented by the formula (6) is preferably 10,000 or less, more preferably 5000 or less, and further preferably 3500. It is as follows.

From the viewpoint of suppressing volatilization, the silanol-modified siloxane with terminals at both ends represented by the formula (6) preferably has a molecular weight of 200 or more, more preferably 300 or more, and further preferably 400 or more.

The molecular weight of the silanol-modified siloxane modified at both ends represented by the above formula (6) can be measured by gel permeation chromatography (GPC).

The silanol modified at both ends is not particularly limited and includes, for example, 1,1,3,3-tetramethyldisiloxanediol-1,3-diol, 1,1,3,3,5,5-hexamethyldisiloxane. Siloxane-1,5-diol, 1,1,3,3,5,5,7,7-octamethyltetrasiloxane-1,7-diol, 1,1,3,3,5,5,7,7 , 9,9-decamethylpentasiloxane-1,9-diol, diol modified polymethyldimethyldisiloxane at both ends, and the like. The silanol-modified siloxane having both terminals may be used alone or in combination of two or more.

A commercially available product may be used as the silanol-modified siloxane having both terminals. The commercially available product is not particularly limited, and examples thereof include X21-5841, KF9701 (all manufactured by Shin-Etsu Chemical Co., Ltd.), and DMS-S12, DMS-S14, DMS-S15, DMS-S21, DMS-S27, DMS-S31, DMS. -S32, DMS-S33, DMS-S35, DMS-S42, DMS-S45, DMS-S51 (above made by Gelest) etc. are mentioned.

The content of the silanol-modified siloxane having both terminals at the end in the silanol composition of the present embodiment is preferably 1 to 80% by mass, more preferably 10 to 60% by mass, and still more preferably the amount of silanol composition. It is 15 to 50% by mass.

When the content of the silanol-modified siloxane modified at both ends is 1% by mass or more, the silanol composition tends to have more excellent crack resistance of the cured product obtained. Further, when the content of the silanol-modified siloxane having both terminals is 80% by mass or less, the silanol composition tends to have further excellent transparency of the obtained cured product.

The silanol composition of the present embodiment preferably has a total content ratio (total content ratio) of sodium (Na) and vanadium (V) of less than 60 mass ppm.

When the total content is less than 60 mass ppm, the silanol composition of the present embodiment tends to have further excellent storage stability.

The content ratio is preferably 20 mass ppm or less, more preferably 12 mass ppm or less, further preferably 2 mass ppm or less, and particularly preferably 1 mass ppm or less, from the viewpoint of further excellent storage stability. is there.

The content ratio of each of Na and V in the silanol composition of the present embodiment is preferably less than 30 mass ppm, more preferably 10 mass ppm or less, and further preferably from the viewpoint of further excellent storage stability. It is 6 mass ppm or less, and particularly preferably 1 mass ppm or less.

The method for controlling the total content ratio to less than 60 mass ppm is not particularly limited, and for example, a method of using powdered cellulose as a filter aid in the filtration step in producing the silanol composition of the present embodiment may be used. Can be mentioned.

Commercially available powdered cellulose is not particularly limited, and examples thereof include KC Flock W50GK (manufactured by Nippon Paper Industries), KC Flock W100-GK (manufactured by Nippon Paper Industries), and cellulose powder 38 μm (400 mesh) passage (manufactured by Wako Pure Chemical Industries). Can be mentioned.

As a method for controlling the total content ratio to less than 60 mass ppm, in addition to the above-described method, a method using a filter aid containing no Na or V may be used.

The respective content ratios of Na and V in the silanol composition can be measured according to the methods described in Examples below.

(Cured product)
The cured product of this embodiment is a cured product of the silanol composition of this embodiment. The cured product of this embodiment is used for radiation resistance or for outer space. The cured product of the present embodiment is obtained by forming a siloxane bond (-Si-O-Si-) by a dehydration condensation reaction of the silanol group (-Si-OH) contained in the silanol composition of the present embodiment. .. The cured product of this embodiment is insoluble in a solvent such as tetrahydrofuran or toluene.

In order to obtain the cured product of this embodiment, for example, the silanol composition of this embodiment may be cured by a known method.

The cyclic silanol (A1) may be polymerized in the absence of a catalyst, or may be polymerized by adding a catalyst.

The catalyst used for the polymerization of cyclic silanol functions to accelerate the hydrolysis and condensation reaction of cyclic silanol. An acid catalyst or an alkali catalyst can be used as the catalyst.

The acid catalyst is not particularly limited, and for example, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trichloroacetic acid, trichloroacetic acid Examples include fluoroacetic acid, oxalic acid, malonic acid, sulfonic acid, phthalic acid, fumaric acid, citric acid, maleic acid, oleic acid, methylmalonic acid, adipic acid, p-aminobenzoic acid, and p-toluenesulfonic acid. ..
The alkali catalyst is not particularly limited, and examples thereof include inorganic bases such as sodium hydroxide, potassium hydroxide, sodium hydrogen carbonate, sodium carbonate, ammonium carbonate, ammonium hydrogen carbonate, aqueous ammonia, and organic amines.

Each of the acid catalyst and the alkali catalyst may be used alone, or two or more kinds may be used in combination.

The amount of the catalyst added can be adjusted depending on the reaction conditions, and is preferably 0.000001 to 2 mol per 1 mol of the hydroxyl group of the cyclic silanol. When the amount added is more than 2 mol per 1 mol of the hydroxyl group of the cyclic silanol, the reaction rate is very high even at a low concentration, so that it is difficult to control the molecular weight and gelation tends to occur.

When obtaining a cured product, the cyclic silanol in the silanol composition can be hydrolyzed and condensed in stages by utilizing an acid catalyst and an alkali catalyst. Specifically, the cyclic silanol in the silanol composition is hydrolyzed and condensed with an acid and then reacted again with a base, or the cyclic silanol is first hydrolyzed and condensed with a base and then acidified again. A cured product can be obtained by reacting. Alternatively, the silanol composition can be obtained by reacting each of the acid catalyst and the alkali catalyst and then mixing the condensate.

The method of curing the silanol composition of the present embodiment is not particularly limited, and examples thereof include a method of heating and curing.

The curing temperature for curing the cured product is preferably 60 to 250°C, more preferably 80 to 200°C.

The curing time for curing the silanol composition of the present embodiment (for example, the thermal curing time for thermally curing) is preferably 10 minutes to 72 hours, more preferably 10 minutes to 48 hours, further preferably 30 minutes. To 48 hours (preferably 1 to 24 hours, more preferably 1 to 12 hours).

The silanol composition of this embodiment can be used as an adhesive. The adhesive of this embodiment contains the silanol composition of this embodiment and is a radiation resistant or space adhesive. The silanol composition of the present embodiment is applied to a base material to form an adhesive layer, and the adhesive layer containing the silanol composition is cured to adhere. The substrate is not particularly limited, and examples thereof include glass, silicon wafers, SiO ₂ wafers, SiN wafers, compound semiconductors, resins, electronic substrates, resins, metals, inorganic substances, organic substances, and polymers.

(Composite membrane)
The composite film of the present embodiment includes a film and the cured product of the present embodiment arranged on the film, and is used for radiation resistance or space use.

The film used for the composite film of the present embodiment is not particularly limited, and examples thereof include materials used as known films, and among these, a polyimide film is preferable.

The polyimide film is not particularly limited and, for example, one obtained by polycondensing at least pyromellitic dianhydride as a monomer (Toray Dupont: Kapton H, Kapton E, Kapton EN, Kapton V, etc., Kaneka Corporation: Various apical), those obtained by polycondensing at least 3,3′,4,4′-biphenyltetracarboxylic dianhydride as a monomer (Ube Industries, Ltd.: Upilex-R, Upilex-S) and the like.

The thickness of the polyimide film is preferably 7.5 to 125 μm.

Further, the polyimide film may be subjected to discharge treatment such as plasma discharge treatment or corona discharge treatment for improving adhesiveness, or may be subjected to surface treatment such as alkali treatment.

The method for forming the coating film is not particularly limited, and is appropriately selected depending on the constituent material, shape, and the like of the base material. When the shape of the substrate is a flat plate such as a film or a sheet, as a forming method, an applicator, a bar coater, a wire bar coater, a roll coater, a curtain flow coater, or the like is used to form a coating film. Can be mentioned. Other forming methods include a dip coating method, a scatter method, a spray method and the like.

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 and the like. The method for measuring the physical properties and the method for evaluating the properties of the silanol compositions obtained by the present invention and the following Examples and Comparative Examples are as follows.

[Evaluation method]
<Atomic oxygen irradiation test and atomic oxygen durability test>
An atomic oxygen (AO) irradiator (FAST atomic oxygen irradiator manufactured by PSI) was used, and a 32% by mass isopropanol solution of the silanol composition was applied to the surface of the bar coater with a polyimide film as a base material. After coating with #6, vacuum drying was performed at 60° C., and the test piece cured at 100° C. for 2 hours and 120° C. for 3 hours was irradiated with atomic oxygen.
Beam speed: 8km・s ^-1
Beam velocity: 3×10 ¹⁵ cm ^-2 ·s ^-1
Degree of vacuum: 10 ^-6 to 10 ^-7 Pa without irradiation (irradiation) 10 ^-3 Pa irradiation conditions:
AO average flow velocity: 3×15 ¹⁵ atoms·cm ⁻¹ ·s ⁻¹
AO speed: 8.11km・s ^-1
Irradiation time: 27.5 hours Irradiation dose: 3×12 ²⁰ atoms·cm ⁻¹
Irradiation temperature: 22 degrees Irradiation vacuum degree: 2.0×10 ^{-2 to} 2.3×10 ^-2
The amount of change in mass of the cured product before and after irradiation with atomic oxygen was measured by placing the mass of the test piece including the base material in an environment of a temperature of 23° C. and a humidity of 50% for 6 hours or more, and then using a microbalance. (Mettler Toledo Co., Ltd., Micro Balance XP6) was used to calculate according to the following formula.
Mass change amount (mg) = post-irradiation test piece mass-pre-irradiation test piece mass The evaluation criteria for the atomic oxygen durability test are that the numerical value of the mass change amount (mg) calculated above is used for the irradiated test piece. Based on the value divided by the area (mm ² ), it was evaluated according to the criteria shown below.
◯ means that it was 1.0×10 ⁻⁵ (mg/mm ² ) or less.
“X” indicates that the amount exceeded 1.0×10 ⁻⁵ (mg/mm ² ).
◯ indicates that the resistance to exposure to atomic oxygen was excellent, and x indicates that the resistance to exposure to atomic oxygen was poor.

<Ultraviolet irradiation test>
Using a UV irradiation device, a 32% by mass isopropanol solution of the silanol composition was applied to the upper surface of the polyimide film by a bar coater No. After applying using No. 6, the test piece was vacuum dried at 60° C., cured at 100° C. for 2 hours and then at 120° C. for 3 hours, and then irradiated with ultraviolet rays (UV) under the following conditions.
UV light intensity: 1-10 solar (at 400 nm or less)
Focal length: 400mm-450mm
Light source: TypeUXL-5001YA (manufactured by USHIO) 5kWXe short arc lamp Irradiation amount: 50ESD
Irradiation rate: 10 ESD/day
Irradiation temperature: -10℃ to -9℃
Irradiation vacuum degree: 1.6×10 ^-4 Pa
Mirror: Dichroic mirror

<Electron beam irradiation test>
An electron beam irradiation device (EB500, Nisshin Denki Co., Ltd.) was used as the electron irradiation device, and a 32% by mass isopropanol solution of the silanol composition was applied to the upper surface of the polyimide film by a bar coater No. After coating using No. 6, the test piece was vacuum dried at 60° C. and cured at 100° C. for 2 hours and then at 120° C. for 3 hours, and electron beam (EB) irradiation was performed under the following conditions.
Accelerating voltage: 500kV
Irradiation time: 2949 sec
EB irradiation amount: 500 kGy
Electron current: 2.0mA
Time Rating: Continuous Temperature: 22℃
Acceleration tube vacuum degree: 1.7×10 ^{−5 to} 4.5×10 ⁻⁵ Pa

<Sunlight absorption rate evaluation>
The sunlight absorptivity (αs) of the cured product was measured using a solar absorptivity measuring device (Spectrophotometer U-4100 manufactured by Hitachi High-Technologies Corporation with a Spectralone coating integrating sphere), and Under the conditions described above, the solar absorptance (αs) before and after irradiation with atomic oxygen, ultraviolet rays, and electron beams was measured.
Scanning wavelength: 240-2,800 nm
Measurement method: Double beam direct ratio metering method Scanning width: 1 nm
Wavelength accuracy: UV/visible range ±0.2 nm, near infrared range ±1.0 nm
Detector: photomultiplier tube/lead sulfide element The ultraviolet resistance test evaluation (sunlight absorption rate evaluation) is based on the difference in the solar absorption rate (αs) before and after AO irradiation, electron beam irradiation, or UV irradiation. Numerical values were calculated according to the following formula, and evaluated according to the criteria shown below.
Change in solar absorptivity=Sunlight absorptivity of post-irradiation test piece-Sunlight absorptivity of pre-irradiation test piece ◯ represents ±1.0×10 ⁻¹ or less.
X indicates that the value was ±1.0×10 ⁻¹ .
◯ indicates that the ability to suppress the increase or decrease in the solar absorptance was excellent, and x indicates that the ability to suppress the increase or decrease in the solar absorptance due to ultraviolet rays was poor.

<Vertical infrared emissivity (ε _N ) measurement>
The vertical infrared emissivity (ε _N ) of the cured product is measured using a vertical infrared emissivity (ε _N ) measuring device (AZ Technology TESA2000) under the following conditions: atomic oxygen, ultraviolet rays, The vertical infrared emissivity (ε _N ) before and after electron beam irradiation was measured.
Wavelength range: 3 μm to 35 μm
Change in vertical infrared emissivity=vertical infrared emissivity of post-irradiation test piece-vertical infrared emissivity of pre-irradiation test piece ◯ means that it was ±1.0×10 ⁻¹ or less.
X indicates that the value was ±1.0×10 ⁻¹ .
◯ indicates that the vertical infrared emissivity increase/decrease was excellent, and x indicates that the vertical infrared emissivity increase/decrease was inferior.

<Outgas test (Outgas suppression)>
Using a polyimide film as a base material, a 32 mass% isopropanol solution of the silanol composition was applied to the surface of the bar coater No. After applying using No. 6, it was vacuum dried at 60° C. to prepare a test piece cured at 100° C. for 2 hours and 120° C. for 3 hours, and measured according to ASTM (American Society for Testing and Materials) E595-93 test method.
〔Measurement condition〕
Degree of vacuum: 7×10 ^-3 Pa or less Material heating temperature: 125±1°C
Emission gas cooling temperature: 23±1℃
Hold time: 24 hours Measurement item: TML, CVCM
Initial sample weight: 200mg-300mg

TML (Total Mass Loss): The mass loss ratio is defined by the following formula.
Mass loss ratio={(sample mass before test-sample mass after test)/sample mass before test}×100(%)
In the evaluation of the outgas test for TML, the value of TML was evaluated according to the criteria shown below.
◯ means that it was less than 1.0%.
× indicates that the amount was over 1.0%.
◯ indicates that the mass loss was the smallest and the performance was excellent, and x indicates that the mass loss was the largest and the performance was inferior.

<Surface adhesiveness evaluation (surface non-adhesiveness)>
The polyimide film was used as a base material and the curable composition was applied to the surface in a thickness of 1 to 3 μm and cured, and then the surface of the cured product was touched with a finger to confirm the presence of tack (surface tackiness). It evaluated by the following evaluation criteria.
◯ means that there was no surface tackiness.
X represents that there was surface tackiness.
◯ means that there was no surface tackiness and the physical properties were excellent, and x means that there was surface tackiness and the physical properties were poor.

<Heat resistance yellowing test>
A 25 μm thick PET film (Toray Industries, Inc., trade name Lumirror) was used as a base material and 40% by mass of the isopropanol solution of the silanol composition was cast on the surface and applied, followed by vacuum drying at 60° C. for 2 hours at 100° C. A test piece cured at 120° C. for 2 hours, at 150° C. for 2 hours, and at 180° C. for 2 hours is further prepared. The cured film prepared to have a thickness of 30 μm is subjected to a heat resistance test at 200° C. for 1000 hours to obtain heat resistance. After the test, the transmittance at 380 nm was evaluated with a transmittance measuring device (a spectrophotometer U-4100 manufactured by Hitachi High-Technologies Corporation with a Spectralone coating integrating sphere installed).
In the evaluation of the heat-resistant yellowing test, the transmittance (%) value was evaluated according to the criteria shown below.
◯ means that it was 50% or more.
X represents less than 50%.
◯ indicates that the recondensation was the least and the performance was excellent, and X indicates that the recondensation was the most and the performance was inferior.

<Calculation of mass percent concentration of coating solution>
Using an ECZ400S manufactured by JEOL Ltd. and a TFH probe as a probe, NMR measurement was performed as follows.
For example, in the case of an isopropanol solution of tetrahydroxytetramethyltetracyclosiloxane and its polymer, 1 g of heavy acetone was added to 0.1 g of an isopropanol solution of tetrahydroxytetramethyltetracyclosiloxane and its polymer, and ¹ 1 H-NMR was measured. The reference peak of the heavy solvent was set to 2.05 ppm, and the number of times of integration was 64.
The mass percent concentration of tetrahydroxytetramethyltetracyclosiloxane and its polymer can be approximately calculated by the following formula.
Mass percent concentration of tetrahydroxytetramethyltetracyclosiloxane and its polymer=(peak integration ratio of methyl group bonded to Si in region of −0.1 to 0.3 ppm/12×304.51)/{(−0 .1 to 0.3 ppm peak integration ratio of methyl group bonded to Si/12×304.51)+(3.7 to 4.1 ppm peak integration value of hydrogen bonded to carbon of isopropanol/ 1×60.1)}
In the above formula, 304.51 means the molecular weight of tetrahydroxytetramethyltetracyclosiloxane, and 60.1 means the molecular weight of isopropanol.

<Measurement of haze>
The haze was measured using a turbidimeter NDH5000W (manufactured by Nippon Denshoku Industries Co., Ltd.) based on JISK7136. The specific operation is shown below.
The haze of the silanol composition was obtained by applying a 42 mass% isopropanol solution of the silanol composition to a bare glass substrate having a thickness of 5 cm×5 cm×0.7 mm (manufactured by Technoprint Co., Ltd.) with a bar coater No. After coating with 40 (manufactured by AS ONE), it was dried under reduced pressure at 60° C. for 1 hour, and haze was measured. As the blank for haze measurement, only a blank glass substrate having a thickness of 5 cm×5 cm×0.7 mm (manufactured by Technoprint Co., Ltd.) was used.
Regarding Examples 10 and 16 and Comparative Example 1, the haze of the silanol composition after 24 hours was also measured.
The haze of the cured product was measured using a sample obtained by heating the sample prepared by the haze measurement of the silanol composition at 100° C. for 2 hours at normal pressure.

<Measurement of film thickness>
The film thickness was calculated by measuring the sample prepared for haze measurement with a surface profilometer (manufacturing name: Kosaka Laboratory Ltd. model: ET4000AK31).

<Confirmation of adhesive strength>
A hemispherical quartz lens having a diameter of 2 mm was placed on the sample prepared by the haze measurement of the silanol composition with a load of 400 g for 3 seconds using a T-3000-FC3 manual die bonder (manufactured by TRESKY). Then, after heating at 100° C. for 2 hours under normal pressure, the glass on which the obtained hemispherical lens was mounted was pushed from the side and the presence or absence of adhesion was confirmed.

<Measurement of area ratio (%) of dehydration condensate (A2)>
A solution prepared by dissolving 1.5 mL of tetrahydrofuran in 0.03 g of the silanol composition was used as a measurement sample.
This measurement sample was used for measurement with Tosoh Corp. HLC-8220GPC.
As the column, TSK guard columns SuperH-H, TSKgel SuperHM-H, TSKgel SuperHM-H, TSKgel SuperH2000, and TSKgel SuperH1000, manufactured by Tosoh Corporation, were used in series, and tetrahydrofuran was used as a mobile phase at a rate of 0.35 ml/min. analyzed.
The detector uses an RI detector, and polymethylmethacrylate standard sample (molecular weight: 2100000, 322000, 87800, 20850, 2000, 670000, 130000, 46300, 11800, 860) manufactured by American Polymer Standards Corporation, and 1, 3, 5 , 7-Tetramethylcyclotetrasiloxane (molecular weight 240.5, manufactured by Tokyo Chemical Industry Co., Ltd.) was used as a standard substance to determine the number average molecular weight and the weight average molecular weight, and the peaks of p=0 and p≧1 were identified, and the cyclic silanol ( The area ratio (%) of each peak of A1) and dehydration condensate (A2) was calculated.
From the cyclic silanol (A1) and the dehydrated condensate (A2), the area ratio (%) of the dehydrated condensate (A2) was calculated from (A2)/[(A1)+(A2)].

<Contents of Na and V, and Content of Transition Metal (Pd)>
Fluorine nitric acid was added to the hydrosiloxane oxidation reaction product, and the sample was transferred to a Teflon (registered trademark) beaker and subjected to heat-drying after being sealed and acid-decomposed. Then, aqua regia was added to the sample, and the completely dissolved solution was adjusted to a constant volume of 20 mL, and quantitative analysis of the metal ratio (mass ppm) in the sample was performed using an ICP mass spectrometer (iCAP Qc manufactured by Thermo Fisher Scientific). ..

<Calculation of Stereoisomeric Ratio of Cyclic Silanol Using ¹ H-NMR Measurement>
Using an ECZ400S manufactured by JEOL Ltd. and a TFH probe as a probe, NMR measurement was performed as follows.
0.1 g of the product and 1 g of heavy acetone were added to the obtained silanol composition, and ¹ H-NMR was measured. The reference peak of the heavy solvent was set to 2.05 ppm, and the number of times of integration was 64.
When tetramethyltetracyclosiloxane is used as a hydrosilane compound as a raw material and is oxidized, ¹ H-NMR of the resulting tetrahydroxytetramethyltetracyclosiloxane shows four isomers in the region of 0.04-0.95 ppm. Six types of peaks of methyl groups bonded to Si were observed.
From the high magnetic field side, hydrogen of the methyl group is all-cis type (0.057ppm), trans-trans-cis type (0.064ppm), trans-trans-cis type (0.067ppm), cis-trans-cis. Type (0.074 ppm), all-trans type (0.080 ppm), trans-trans-cis type (0.087 ppm) were observed in this order. The waveforms of the six peaks were separated by Lorentz transformation using Delta5.2.1 (manufactured by JEOL Ltd.), and the stereoisomeric ratio (%) of each cyclic silanol was calculated from the peak intensities of these hydrogens.

<Preparation of each stereoisomer>
・All-cis form (cyclic silanol (B1))
It was synthesized according to the synthesis example of Inorganic Chemistry Vol.49, No.2, 2010.
・Cis-trans-cis form (cyclic silanol (B2))
The recrystallized product obtained in Example 1 was used.
・All-trans form (cyclic silanol (B4))
Using a solution obtained by further concentrating the 10 wt% silanol tetrahydrofuran and dichloromethane mixed solution prepared in Example 1, and concentrating it to 20 wt% silanol, the stereoisomers of the stereoisomers were obtained using liquid chromatography under the following conditions. The collection was done.
Liquid chromatography conditions;
Equipment GL Science Liquid Chromatography Pump: PU715
Column oven: CO705
Fraction Collective: FC204YMC-PackSIL-06 φ30mm×250mm
Eluent: Cyclohexane/EtoAc =60/40
Flow rate: 40 mL/min
Injection volume: 5mL
Temperature: 40℃
Detection: The obtained fractions were evaluated and detected by ELSD measurement.
Crystals of the all-trans form were obtained by allowing the obtained eluate of the all-trans form to stand, and the crystals were collected by filtration.
・Trans-trans-cis form (cyclic silanol (B3))
The eluate obtained by the same method as for the all-trans form was concentrated and then replaced with isopropanol.

[Example 1]
(Preparation of silanol composition)
In a reaction vessel, distilled water 28 g, tetrahydrofuran (THF, Wako Pure Chemical Industries, Ltd.) 960 mL, Pd/C (10% palladium-carbon, NE Chemcat Ltd.) 3.7 g were put and mixed, and then the temperature of the reaction vessel Was maintained at 5°C.
Wherein the reaction vessel 1,3,5,7 81g slowly added (Tokyo Kasei, also described as D4H), until after stirring for 2 hours, the SiH group at ¹ H-NMR disappeared 1.8 g of Pd/C (10% palladium/carbon) was divided into 3 times, and the reaction was performed for a total of 17 hours. Regarding the disappearance of the SiH group, the reaction liquid was subjected to ¹ H-NMR measurement with a heavy acetone solution having a concentration of 1% by mass of the reaction liquid using NMR (ECZ400S) manufactured by JEOL Ltd., and the disappearance of 4 to 5 ppm of the SiH group was confirmed.
75 g of magnesium sulfate was added to the reaction solution, and the mixture was stirred at 5°C for 30 minutes, and then Celite No. 450 g of 545 (manufactured by Wako Pure Chemical Industries, Ltd.) was charged into the funnel using tetrahydrofuran. Subsequently, the reaction solution is passed through the celite, and the celite is washed with 1.5 L of tetrahydrofuran, and 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane (hereinafter, 2057 g of a THF solution containing (also referred to as D4OH) was obtained. This solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 g (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure to obtain 89 g of a D4OH concentrate (that is, a hydrosiloxane oxidation reaction product).
Furthermore, the D4OH concentrate: silanol-modified siloxane modified at both ends represented by the above formula (6): tetrahydrofuran is 8:2:90 in mass ratio (that is, the silanol-modified siloxane modified at both ends is 20 mass%). As such, a silanol-modified siloxane with both terminals (X21-5841, manufactured by Shin-Etsu Chemical Co., Ltd., molecular weight 1000) and tetrahydrofuran were added to the D4OH concentrate, and the tetrahydrofuran was distilled off with an evaporator to obtain a silanol composition.
Using the obtained silanol composition, haze was measured according to the method described above (measurement of haze). Further, the ratio of all-trans type and cis-trans-cis type cyclic silanol was calculated by ¹ H-NMR.
Further, the content of the transition metal Pd was calculated as described above.

(Confirmation of curing of silanol composition, confirmation of adhesive strength, and measurement of light transmittance of cured product)
The silanol composition obtained in the above (Preparation of silanol composition) was applied onto a quartz glass using a bar coater No. 2 was applied to a thickness of 3 μm, quartz glass was placed thereon, and cured by a temperature program of 80° C. for 6 hours and 180° C. for 6 hours.
After curing, only one glass plate was lifted, and after confirming that the glass was adhered, the haze of the obtained cured product was measured.

(Check crack resistance after quenching after hardening)
The cured product was taken out from an oven at 180° C. to room temperature at 25° C., rapidly cooled, and cracks were observed with a microscope.

[Example 2]
Example 1 except that the D4OH concentrate: both-end silanol-modified siloxane: tetrahydrofuran was made to have a mass ratio of 6:4:90 (that is, the both-end silanol-modified siloxane content was 40% by mass). A silanol composition was obtained in the same manner as in, and the same experiment was performed.

[Example 3]
A silanol composition was obtained in the same manner as in Example 1 except that the both-end silanol-modified siloxane (Shin-Etsu Chemical X21-5841, molecular weight 1000) was replaced with the both-end silanol-modified siloxane (Shin-Etsu Chemical KF-9701, molecular weight 3000). The thing was obtained and the experiment was conducted similarly.

[Example 4]
Both terminal silanol-modified siloxane (Shin-Etsu Chemical X21-5841, molecular weight 1000) was replaced with both-terminal silanol-modified siloxane (Shin-Etsu Chemical KF-9701, molecular weight 3000), and D4OH concentrate: both terminal silanol-modified siloxane: tetrahydrofuran Was obtained in the same manner as in Example 1 except that the mass ratio was 6:4:90 (that is, the content of the silanol-modified siloxane modified at both ends was 40 mass %) to obtain a silanol composition, The same experiment was conducted.

[Example 5]
Silanol was modified in the same manner as in Example 1 except that the silanol-modified siloxane with both terminals (X21-5841, Shin-Etsu Chemical Co., Ltd., molecular weight 1000) was replaced with the silanol-modified siloxane with both terminals (DMS-S15, Gelest, molecular weight 2000-3500). The composition was obtained and the same experiment was conducted.

[Example 6]
Both terminal silanol modified siloxane (Shin-Etsu Chemical X21-5841, molecular weight 1000) was replaced with both terminal silanol modified siloxane (Gelest DMS-S15, molecular weight 2000-3500), and D4OH concentrate: Both terminal silanol modified siloxane: A silanol composition was obtained in the same manner as in Example 1 except that the mass ratio of tetrahydrofuran was 6:4:90 (that is, the content of the silanol-modified siloxane modified at both ends was 40 mass %). The same experiment was conducted.

[Example 7]
(Preparation of silanol composition)
In a reaction vessel, distilled water 28 g, tetrahydrofuran (THF, Wako Pure Chemical Industries, Ltd.) 960 mL, Pd/C (10% palladium-carbon, NE Chemcat Ltd.) 3.7 g were put and mixed, and then the temperature of the reaction vessel Was maintained at 5°C.
81 g of 1,3,5,7-tetramethylcyclotetrasiloxane (manufactured by Tokyo Kasei, also referred to as D4H) was gradually added to the reaction vessel, and after stirring for 2 hours, SiH group disappeared by ¹ H-NMR. Until then, 1.8 g of the above Pd/C (10% palladium-carbon) was added in 3 batches, and the reaction was carried out for a total of 17 hours.
The reaction solution was subjected to ¹ H-NMR measurement with a heavy acetone solution having a concentration of 1% by mass of the reaction solution using NMR (ECZ400S) manufactured by JEOL Ltd., and the disappearance of 4 to 5 ppm of SiH group was confirmed.
75 g of magnesium sulfate was added to the reaction solution, and the mixture was stirred at 5°C for 30 minutes, and then Celite No. 450 g of 545 (manufactured by Wako Pure Chemical Industries, Ltd.) was charged into the funnel using tetrahydrofuran. Then, the reaction solution is passed through the celite, and the celite is washed with 1.5 L of tetrahydrofuran, and 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane (hereinafter, Also referred to as D4OH) 2057 g of a THF solution containing was obtained.
This solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 g (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure to obtain 89 g of a D4OH concentrate (that is, a hydrosiloxane oxidation reaction product).
Furthermore, silica particles (MEKST-40, manufactured by Nissan Chemical Industries, particle size 40 nm) were added to the D4OH concentrate so that the mass ratio of D4OH concentrate:silica was 50:50, and the solid content concentration was 16 mass. A silanol composition (isopropanol solution) was obtained by adding isopropanol so that the ratio became 100%.
Using the obtained silanol composition, haze was measured according to the method described above (measurement of haze), and the peak area in the differential molecular weight distribution curve of GPC was measured. The ratio of all-cis type and cis-trans-cis type cyclic silanols was calculated by ¹ H-NMR.
Further, the content of the transition metal Pd was calculated as described above.

(Confirmation of curing of silanol composition, confirmation of adhesive strength, and measurement of light transmittance of cured product)
8.3 g of the silanol composition obtained in the above (Preparation of silanol composition) was placed on a quartz glass using a bar coater No. It was applied to a thickness of 3 μm using No. 2 and quartz glass was placed thereon and cured by a temperature program of 80° C. for 6 hours and 180° C. for 6 hours.
After curing, only one glass plate was lifted, and after confirming that the glass was adhered, the haze of the obtained cured product was measured.

(Evaluation of wear resistance of cured products)
A bar coater No. 10 was prepared by applying a primer SHP470FT2050 (manufactured by Momentive) to a polycarbonate plate (Taquilon 1600) of 10 cm square and 1 mm thick. After being coated with 16 (manufactured by As One), it was cured in an oven at 30° C. for 30 minutes and 120° C. for 30 minutes to obtain a polycarbonate plate coated with a 2 μm primer.
On the polycarbonate plate, the silanol composition obtained in the above (Preparation of silanol composition) was applied with a bar coater No. After being applied to the polycarbonate plate coated with the primer in 16, the cured plate was obtained by curing in an oven at 100° C. for 2 hours and then at 120° C. for 2 hours.
The obtained cured plate was subjected to a Taber abrasion test for 500 times at a rotation speed of 60 rpm using a 101 TABER TYPE ABRASION TESTER (manufactured by Yasuda) in which CALIBRASE CS-10F (manufactured by TABER INDUSTRIES) was attached to a wear wheel.
In addition, before performing a Taber abrasion test, all the measurement samples used the abrasion wheel ST-11 REFACEING STONE (made by TABER INDUSTRIES), and performed 25 times polishing at the rotation speed of 60 rpm.
The Haze of the measurement sample after the Taber abrasion test was measured using HASE METER NDH 5000SP (manufactured by NIPPON DENSHOKU), and the increase in Haze before and after the Taber abrasion test (ΔHaze (%)) was calculated.

[Example 8]
An experiment similar to that of Example 7 was performed, except that silica particles were added so that the mass ratio of D4OH concentrate:silica was 75:25 (silica addition ratio was 25 mass %).

[Example 9]
(Preparation of silanol composition)
After adding 28 g of distilled water, 960 mL of tetrahydrofuran (THF, Wako Pure Chemical Industries, Ltd.), 3.7 g of Pd/C (10% palladium/carbon, manufactured by NE Chemcat) to the reaction vessel and mixing, temperature of the reaction vessel Was maintained at 5°C.
81 g of 1,3,5,7-tetramethylcyclotetrasiloxane (manufactured by Tokyo Kasei, also referred to as D4H) was gradually added to the reaction vessel, and after stirring for 2 hours, SiH group disappeared by ¹ H-NMR. Until then, 1.8 g of Pd/C (10% palladium/carbon) was added in 3 batches, and the reaction was carried out for a total of 17 hours.
The reaction solution was subjected to ¹ H-NMR measurement with a heavy acetone solution having a concentration of 1% by mass of the reaction solution using NMR (ECZ400S) manufactured by JEOL Ltd., and the disappearance of 4 to 5 ppm of SiH group was confirmed.
After adding 75 g of magnesium sulfate to the reaction solution and stirring the mixture at 5° C. for 30 minutes, 450 g of powdered cellulose KC Flock W50GK (manufactured by Nippon Paper Industries) as a filter aid was charged into the funnel using tetrahydrofuran. Subsequently, the powdery cellulose is passed through the reaction liquid, and the powdery cellulose is washed with 1.5 L of tetrahydrofuran to obtain 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane ( Hereinafter, also referred to as D4OH.) 2057 g of a THF solution containing was obtained.
The solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure to obtain a silanol composition (89 g) which was a hydrosiloxane oxidation reaction product.
Using the obtained silanol composition, haze was measured according to the method described above (measurement of haze), and the peak area in the differential molecular weight distribution curve of GPC was measured.
Further, the ratio of all-trans type and cis-trans-cis type cyclic silanol was calculated by ¹ H-NMR. The Na and V contents and the transition metal (Pd) contents were measured as described above.

(Confirmation of curing of silanol composition, confirmation of adhesive strength, measurement of light transmittance of cured product)
8.3 g of the silanol composition obtained in the above (Preparation of silanol composition) was placed on a quartz glass using a bar coater No. 2 was applied to a thickness of 3 μm, quartz glass was further placed thereon, and cured by a temperature program of 80° C. for 6 hours and 180° C. for 6 hours. After curing, only one glass plate was lifted and it was confirmed that the quartz glass was bonded.
Then, the light transmittance in 400-800 nm of the obtained cured product was measured.

(Storage stability test of silanol composition)
The obtained silanol composition was left at room temperature of 25° C. for 1 month.
It was confirmed whether the silanol composition was solidified by touching with a spatula, and the storage stability was evaluated by the presence or absence of solidification.
In the table, ◯ indicates that it did not solidify, and x indicates that it solidified.

[Example 10]
(Preparation of silanol composition)
After adding 28 g of distilled water, 960 mL of tetrahydrofuran (manufactured by Wako Pure Chemical Industries, Ltd.), 3.7 g of Pd/C (10% palladium/carbon, manufactured by NE Chemcat) to the reaction vessel and mixing, the temperature of the reaction vessel was adjusted to 5 Maintained at 0°C.
Wherein the reaction vessel 1,3,5,7 81g slowly added (Tokyo Kasei, also described as D4H), until after stirring for 2 hours, the SiH group at ¹ H-NMR disappeared 1.8 g of Pd/C (10% palladium/carbon) was divided into 3 times, and the reaction was performed for a total of 17 hours. The disappearance of the SiH group was measured by ¹ H-NMR of the reaction solution with a heavy acetone solution having a concentration of 1% by mass of the reaction solution using NMR (ECZ400S) manufactured by JEOL Ltd., and the disappearance of the SiH group existing in 4 to 5 ppm was confirmed. confirmed.
75 g of magnesium sulfate was added to the reaction solution, and the mixture was stirred at 5°C for 30 minutes. Celite No. 450 g of 545 (manufactured by Wako Pure Chemical Industries, Ltd.) was charged into the funnel using tetrahydrofuran. Subsequently, the reaction solution is passed through the celite, and the celite is washed with 1.5 L of tetrahydrofuran, and 1,3,5,7-tetrahydroxy-1,3,5,7-tetramethyltetracyclosiloxane (hereinafter, 2057 g of a THF solution containing (also referred to as D4OH) was obtained. This solution was concentrated with an evaporator in a water bath at 15° C. until the remaining amount was 587 g (649 mL), and the solution was poured into a mixed solvent of 4.4 L of tetrahydrofuran and 217 mL of dichloromethane. The mixture was allowed to stand at 5° C. for 4 hours, then the precipitated insoluble material was filtered under reduced pressure to recover 22 g of a crystalline solid. 6169 g of the filtrate in the soluble portion was concentrated under reduced pressure, and concentrated to a mixed solution of 10% by mass of silanol composition in tetrahydrofuran and dichloromethane. 10 g of a mixed solution of 10% by mass silanol composition in tetrahydrofuran and dichloromethane was concentrated under reduced pressure to 1 g, and then 100 g of isopropanol was added again. Further, the mixture was concentrated again under reduced pressure to prepare a silanol composition (isopropanol solution) having a predetermined concentration.
Physical properties such as haze were evaluated using the obtained silanol composition. Moreover, the stereoisomeric ratio of cyclic silanol was calculated by ¹ H-NMR. FIG. 1 shows the ¹ H-NMR spectrum.

[Example 11]
To the silanol composition (isopropanol solution) prepared in Example 10, the all-trans form (cyclic silanol (B4)) prepared in (Preparation of each stereoisomer) was added, and the all-tras form ratio was 43. The same experiment as in Example 10 was performed except that the percentage was changed to %.

[Example 12]
To the silanol composition (isopropanol solution) produced in Example 10, the all-trans form (cyclic silanol (B4)) prepared in (Preparation of each stereoisomer) was added, and the all-tras form ratio was 56. The same experiment as in Example 10 was performed except that the percentage was changed to %.

[Example 13]
To the silanol composition (isopropanol solution) prepared in Example 10, the all-cis form (cyclic silanol (B1)) prepared in (Preparation of each stereoisomer) was added, and the all-cis form ratio was 31. The same experiment as in Example 10 was performed except that the percentage was changed to %.

[Example 14]
To the silanol composition (isopropanol solution) prepared in Example 10, the all-cis form (cyclic silanol (B1)) prepared in (Preparation of each stereoisomer) was added, and the all-cis form ratio was 41. The same experiment as in Example 10 was performed except that the percentage was changed to %.

[Example 15]
The trans-trans-cis form (cyclic silanol (B3)) prepared in the above (preparation of stereoisomers) was added to the silanol composition (isopropanol solution) prepared in Example 10 to give trans-trans-cis. The same experiment as in Example 10 was conducted except that the body ratio was set to 66%.

[Example 16]
An experiment similar to that of Example 10 was performed, except that the recrystallization temperature of Example 10 was set to −40° C. FIG. 2 shows the ¹ H-NMR spectrum.

[Comparative Example 1]
The same test as in Example 1 was conducted using the resin described in Example 1 of JP 2011-42755 A.

Tables 1 and 2 show the physical properties and evaluation results of the silanol compositions and cured products obtained in the examples and comparative examples.

In Tables 1 and 2, “−” indicates “absent” regarding components and “not measured” regarding characteristics.

The radiation resistant or outer space silanol composition of the present invention is a material used for objects exposed to atomic oxygen, ultraviolet rays, electron beams and the like used in outer space, a fast breeder reactor, and nuclear power. As a material used for materials exposed to radiation such as electron beams at power plants, radiation irradiation facilities, nuclear fuel disposal work, decommissioning work, uranium enrichment facilities, radioactive waste treatment facilities, spent fuel reprocessing facilities, etc. It has industrial applicability.

The radiation resistant or space silanol composition of the present invention is specifically used for a heat control material, a heat insulating film, a sheet, a woven fabric, a paint, a solar reflective material, a heat conductive adhesive, a thermal filler, Structure panel (mainly composite material), truss, tether (string), debris bumper (plate or cushion material that protects spacecraft from space debris), solar paddle (including solar cell protective cover), electric wire, insulation Coatings, heaters, antenna components, cameras, monitors, lights and their protective covers (including radio wave transmission radomes), robot arms, outer space for spacesuits, heat insulating tiles and window materials for space shuttles, moons and planets. Films, sheets, fabrics, foam materials of structures, exploration vehicles and satellites, large deployable structures, space inflatable structures or solar sails (solar sails; large structures using photon pressure propulsion) at upper space stations or spacecraft And industrial use in the fields of shape memory materials, space elevator cables and elevator housings, films, sheets, and foam materials for deploying orbits (deorbits that utilize increased air resistance) for end-of-operation spacecraft. Have sex.

Further, the radiation-resistant or outer space silanol composition of the present invention specifically includes a fast breeder reactor, a nuclear power plant, a radiation irradiation facility, a nuclear fuel disposal operation, a decommissioning operation, a uranium enrichment facility, a radioactive waste treatment. Films and sheets to protect equipment, electronic substrates, semiconductors, resins, metals, inorganic substances, organic substances, and polymers from radiation when exposed to a large dose level radiation environment such as facilities and spent fuel reprocessing facilities. It has industrial applicability in the fields of textiles, foaming agents and shape memory materials, adhesives, etc.

Claims (14)

A silanol composition containing a cyclic silanol represented by the following formula (1) (A1) and a dehydration condensation product (A2) thereof, which is used for radiation resistance or for outer space.
(In the formula (I), each R is independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a fluorine-substituted linear or branched alkyl group having 1 to 4 carbon atoms, or It is a substituted linear or branched alkyl group having 1 to 4 carbon atoms, and n is an integer of 2 to 10.) The silanol composition according to claim 1, wherein the cyclic silanol (A1) is represented by the following formula (1).
(In the formula (1), R ^{1 to} R ⁴ are each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, or a fluorine-substituted linear or branched alkyl group having 1 to 4 carbon atoms. Or a non-substituted linear or branched alkyl group having 1 to 4 carbon atoms.) The cyclic silanol (A1) is a cyclic silanol (B1) to (B4) represented by the following formulas (2) to (5):
(In formulas (2) to (5), R ^{1 to} R ⁴ are each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, or a linear or branched C ¹ having a fluorine atom. To 4 or an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms.)
Containing
When the ratio (mol %) of the cyclic silanol (B2) to the total amount of the cyclic silanols (B1) to (B4) is b, 0<b≦20 is satisfied,
The silanol composition according to claim 1 or 2. In the measurement of gel permeation chromatography, the area of the dehydrated condensate (A2) is more than 0% and 50% or less with respect to the total area of the cyclic silanol (A1) and the dehydrated condensate (A2),
The silanol composition according to any one of claims 1 to 3. The proportion of transition metal is less than 1 mass ppm,
The silanol composition according to any one of claims 1 to 4. Including solvent,
The silanol composition according to any one of claims 1 to 5. Including silica particles having an average particle size of 1 nm or more and 100 nm or less,
The silanol composition according to any one of claims 1 to 6. Including a silanol-modified siloxane having both terminals represented by the following formula (6):
The silanol composition according to any one of claims 1 to 7.
(In the formula (6), R′ is each independently a fluorine atom, an aryl group, a vinyl group, an allyl group, a linear or branched C 1 -C 4 alkyl group substituted with fluorine, Alternatively, it is an unsubstituted linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 0 to 1000.) The total content of Na and V is less than 60 mass ppm,
The silanol composition according to any one of claims 1 to 8. A cured product of the silanol composition according to any one of claims 1 to 9, which is used for radiation resistance or for outer space. An adhesive comprising the silanol composition according to any one of claims 1 to 9 and used for radiation resistance or outer space. A film,
A cured product arranged on the film,
And a composite film used for radiation resistance or space use,
A composite film, wherein the cured product is the cured product according to claim 10. A curing method for thermally curing the silanol composition according to claim 1.
A curing method in which the curing temperature is 60 to 250°C. The curing method according to claim 13, wherein the curing time is 10 minutes to 72 hours.