An open cage benzocyclobutene-based poly(silsesquioxane) thermoset resin, its preparation method and use

Abstract

The application belongs to the technical field of organic-inorganic thermosetting resin materials, and particularly relates to an open-cage benzocyclobutene-based polysilsesquioxane thermosetting resin and a preparation method and application thereof. The application provides an open-cage benzocyclobutene-based polysilsesquioxane, and a structural formula is shown as formula 1 or formula 2. The thermosetting resin based on the open-cage benzocyclobutene-based polysilsesquioxane has an ultralow dielectric constant and low dielectric loss; and has high heat resistance and good flexibility, and can not only be prepared into a solid block material through a casting method, but also can be prepared into a flexible thermosetting resin film through a spin coating or drop coating method. The application takes the open-cage POSS as a monomer, and prepares a homogeneous intramolecular organic-inorganic hybrid thermosetting resin through self-thermal crosslinking, and overcomes the problems of uneven dispersion of POSS, a low addition amount threshold and limited improvement of material performance when the POSS modifies a polymer.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of organic-inorganic thermosetting resin materials, and particularly relates to an open cage type benzocyclobutene-based poly silesquioxane thermosetting resin as well as a preparation method and application thereof. BACKGROUND

[0002] The rapid development of Internet of Things (IOT) and high frequency (5G) communication technology puts forward higher requirements on the high integration and efficient signal transmission of electronic devices. This means that more functional circuits are compressed into smaller spaces, resulting in increased device capacitance and resistance, and causing problems such as crosstalk noise, signal delay and power consumption. The transmission loss of electrical signals in digital circuits mainly includes conductor loss (T LC ) and dielectric loss (T LD ). The dielectric loss (T LD ) is closely related to the dielectric constant (k) and dielectric loss (tan δ) of the dielectric material, and follows the formula:

[0003]

[0004] where K is a constant, f is the frequency, and c is the speed of light. Therefore, there is an urgent need to develop insulating materials with low dielectric constant and low dielectric loss to meet the rapid development of electronic communication technology. In addition, it is also desirable that the developed dielectric material has excellent thermal stability to meet the post-processing process at 350℃ high temperature, and appropriate flexibility to meet the preparation and development of flexible electronic components. In summary, the development of insulating materials with low dielectric constant, low dielectric loss, good thermal stability and appropriate flexibility is of great significance to promote the development of the electrical communication industry.

[0005] Polyhedral oligomeric silsesquioxanes (POSS) are a class of soluble, melt-processable, intramolecular organic-inorganic hybrid nanomolecules, whose composition includes a hollow inorganic structure constructed by Si-O and a carbon-hydrogen group (R). The inorganic hollow structure of POSS has a high free volume fraction, which is an ideal building block for low dielectric constant materials; its organic component has strong designability, making it widely used as a nanofiller to modify resin matrixes such as epoxy resin, bismaleimide resin, cyanate ester resin, etc. However, due to the inherent polarity difference between POSS and resin materials, at a high addition amount, POSS inevitably exists in the resin matrix in the form of molecular clusters, forming a large number of heterogeneous interfaces and leading to interfacial polarization of the composite material, which is not conducive to further reducing the dielectric constant and loss of the resin. Related technologies disclose a thermoset material based on the self-crosslinking of closed cage benzocyclobutene-based POSS (T8), which avoids the compatibility problem in traditional modification methods, realizes the uniform dispersion of a large number of hollow cage structures in the resin matrix, and the prepared material has low dielectric properties (~2.2), however, the closed cage T8 structure with too high rigidity and the ultra-high functionality (=8) make the cured product brittle, which is difficult to be practically applied. SUMMARY

[0006] Therefore, the purpose of the present application is to provide an open cage benzocyclobutene-based polysilsesquioxane thermoset resin and a preparation method and application thereof. The open cage benzocyclobutene-based polysilsesquioxane thermoset resin has good flexibility, and has ultra-low dielectric constant, low dielectric loss, good thermal stability and high heat resistance.

[0007] The present application provides an open cage benzocyclobutene-based polysilsesquioxane, the structural formula is shown in formula 1 or formula 2:

[0008]

[0009] In the formula, R1 is selected from the following structures: phenyl, cyclohexyl, n-pentyl, trifluoro-n-pentyl or methyl; R2 is selected from the following structures:

[0010]

[0011] R3, R4, R5 and R6 are independently selected from the following structures: H, alkyl, cycloalkyl, cycloalkoxy, alkylthio, alkylamino, alkenylamino, aryl, heteroaryl, substituted alkyl, substituted cycloalkyl, substituted cycloalkoxy, substituted alkylthio, substituted alkylamino, substituted alkenylamino, substituted aryl or substituted heteroaryl.

[0012] Preferably, in R3, R4, R5 and R6, the alkyl group is C1-C6 alkyl, the cycloalkyl group is C3-C6 cycloalkyl, the cycloalkoxy group is 3-7 membered cycloalkoxy, the alkylthio group is C1-C6 alkylthio, the alkylamino group is C1-C6 alkylamino, the alkenylamino group is C2-C6 alkenylamino, the aryl group is C6-C 12 Preferably, in R3, R4, R5 and R6, the alkyl group is C1-C6 alkyl, the cycloalkyl group is C3-C6 cycloalkyl, the cycloalkoxy group is 3-7 membered cycloalkoxy, the alkylthio group is C1-C6 alkylthio, the alkylamino group is C1-C6 alkylamino, the alkenylamino group is C2-C6 alkenylamino, the aryl group is C6-C

[0013] Preferably, the structure of the open-cage type benzocyclobutenyl polysilsesquioxane is shown in formula 3 or formula 4:

[0014]

[0015] The present application also provides a preparation method of the open-cage type benzocyclobutenyl polysilsesquioxane described in the above technical solution, which comprises the following steps:

[0016] Mixing trialkoxysilane coupling agent, alkali metal hydroxide, water and first organic solvent to perform reflux reaction to obtain open-cage type silanol alkali metal salt polysilsesquioxane;

[0017] Mixing the open-cage type silanol alkali metal salt polysilsesquioxane, vinyl chlorosilane, first catalyst and second organic solvent to perform etherification reaction to obtain vinyl open-cage type polysilsesquioxane;

[0018] Mixing the vinyl open-cage type polysilsesquioxane, benzocyclobutenyl silane compound, second catalyst and third organic solvent to perform silicon-hydrogen addition reaction to obtain open-cage type benzocyclobutenyl polysilsesquioxane;

[0019] The structure of the trialkoxysilane coupling agent, vinyl chlorosilane and benzocyclobutenyl silane compound is shown in formula 5, formula 6 and formula 7 respectively:

[0020]

[0021] Preferably, the alkoxy group in the trialkoxysilane coupling agent is methoxy or ethoxy.

[0022] Preferably, the molar ratio of the alkali metal hydroxide and trialkoxysilane coupling agent is 1:1.5-1:3.

[0023] Preferably, the molar ratio of the alkali metal element in the open-cage type silanol alkali metal salt polysilsesquioxane and vinyl chlorosilane is 1:2-1:4.

[0024] Preferably, the molar ratio of the vinyl group to the benzocyclobutenylsilane compound in the vinyl open-cage polysilsesquioxane is 1:1 to 1:1.5.

[0025] The present invention also provides the use of the open-cage benzocyclobutenyl polysilsesquioxane described in the above technical solution or the open-cage benzocyclobutenyl polysilsesquioxane obtained by the above preparation method in the field of telecommunications.

[0026] The present invention also provides a curing material, which is obtained by cross-linking and curing the open-cage benzocyclobutenyl polysilsesquioxane described in the above technical solution or the open-cage benzocyclobutenyl polysilsesquioxane obtained by the above preparation method.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention provides an open-cage benzocyclobutenyl polysilsesquioxane, the structural formula of which is shown in Formula 1 or Formula 2:

[0029]

[0030] In the formula, R1 is selected from the following structures: phenyl, cyclohexyl, n-pentyl, trifluoro-n-pentyl or methyl; R2 is selected from the following structures:

[0031]

[0032] R3, R4, R5 and R6 are independently selected from the following structures: H, alkyl, cycloalkyl, cycloalkoxy, alkylthio, alkylamino, alkenylamino, aryl, heteroaryl, substituted alkyl, substituted cycloalkyl, substituted cycloalkoxy, substituted alkylthio, substituted alkylamino, substituted alkenylamino, substituted aryl or substituted heteroaryl.

[0033] The open cage type benzocyclobutene based polyhedral oligomeric silsesquioxane (POSS) of the present application not only has a larger outwardly expanding cage type hollow structure, and can be made into a self-crosslinking high heat-resistant thermoset material, breaking through the current predicament of ultra-low dielectric constant material; moreover, due to the limitation of the number of special structure derived sites, it can accurately carry only 3 or 4 active organic groups participating in curing, and can effectively avoid the problem of excessive crosslinking of high-functionality closed cage POSS curing; secondly, the inorganic cage structure of the open cage POSS is moderately opened, and the rigidity is moderately reduced compared with the closed cage POSS, which is beneficial to form a thermosetting flexible film. The open cage POSS molecule functionalized by benzocyclobutene side groups is used in the present application to prepare a molecular level homogeneous organic-inorganic thermosetting resin by itself thermal crosslinking, realizing the unity of low dielectric performance, heat resistance and flexibility of the thermosetting material; the resin of the present application not only can be thermally cured to form a block material with low dielectric constant and loss, but also can be prepared into a flexible film, meeting the needs of ultra-low dielectric constant in the special film field, and having important significance for the field of wireless communication such as 5G electronic packaging, printed circuit board and radar antenna cover.

[0034] The data of the examples show that the POSS-based thermosetting resin of the present application has ultra-low dielectric constant, low dielectric loss at 1MHz frequency; and has high heat resistance, good flexibility, and can not only be prepared into a solid block material by casting method, but also can be prepared into a flexible thermosetting resin film by spin coating or drop coating method. The open cage configuration POSS is used as a monomer in the present application to prepare a homogeneous intramolecular organic-inorganic hybrid thermosetting resin by itself thermal crosslinking, overcoming the problems of uneven dispersion of POSS, low addition amount threshold and limited improvement of material performance when POSS is used to modify polymers. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0036] Figure 1 NMR data of OP1B3-POSS 1 H, 13 C, 29 Si spectrum data;

[0037] Figure 2 NMR data of OP2B4-POSS 1 H, 13 C, 29 Si spectrum data;

[0038] Figure 3NMR data for OP0B8-POSS 1 H, 13 C, 29 Si spectral data

[0039] Figure 4 NMR data for OP0B4T4-POSS 1 H, 13 C, 29 Si spectral data

[0040] Figure 5 Broadband dielectric constant data for open cage benzocyclobutene-based POSS resins and comparative resins

[0041] Figure 6 Broadband dielectric loss data for open cage benzocyclobutene-based POSS resins and comparative resins

[0042] Figure 7 Thermogravimetric analysis curves for open cage benzocyclobutene-based POSS resins and comparative resins

[0043] Figure 8 Young's modulus data for open cage benzocyclobutene-based POSS resins and comparative resins

[0044] Figure 9 Physical photographs of bulk materials, flexible film materials made from closed cage c-OP0B8, open cage c-OP1B3 and c-OP2B4. DETAILED DESCRIPTION

[0045] The present invention provides an open cage benzocyclobutene-based polyhedral oligomeric silsesquioxane (POSS) having the structure of Formula 1 or Formula 2:

[0046]

[0047] wherein R1is selected from the group consisting of phenyl, cyclohexyl, n-pentyl, trifluoro-n-pentyl, or methyl; and R2is selected from the group consisting of:

[0048]

[0049] R3, R4, R5, and R6are independently selected from the group consisting of H, alkyl, cycloalkyl, cycloalkoxy, alkylthio, alkylamino, alkenylamino, aryl, heteroaryl, substituted alkyl, substituted cycloalkyl, substituted cycloalkoxy, substituted alkylthio, substituted alkylamino, substituted alkenylamino, substituted aryl, or substituted heteroaryl.

[0050] In the present invention, “*” represents a point of attachment.

[0051] In the present application, the R1 is an inert organic structure of POSS, phenyl, cyclohexyl, trifluoro-n-pentyl, n-pentyl or methyl, respectively as shown below, and the R1 is preferably phenyl;

[0052]

[0053] In the present application, the R2 is an active organic group in POSS for cross-linking; in R3, R4, R5 and R6, the alkyl is preferably C1-C6 alkyl, the cycloalkyl is preferably C3-C6 cycloalkyl, the cycloalkoxy is preferably 3-7 membered cycloalkoxy, the alkylthio is preferably C1-C6 alkylthio, the alkylamino is preferably C1-C6 alkylamino, the alkenylamino is preferably C2-C6 alkenylamino, the aryl is preferably C6-C 12 The aryl preferably includes benzo C3-C6 cycloalkyl, the heteroaryl preferably is 5-12 membered heteroaryl, the 5-10 membered heteroaryl preferably contains 1-3 N, O or S heteroatoms, and the heteroaryl preferably includes benzo 5-6 membered heterocyclyl; and R3, R4, R5 and R6 are all preferably methyl.

[0054] In the present application, the substitution preferably includes halogenation, and the halogenation preferably includes F, Cl, Br or I substitution.

[0055] In the present application, the structural formula of the open-cage configuration benzosuberenyl polyhedral oligomeric silsesquioxane (POSS) is preferably as shown in formula 3 or formula 4:

[0056]

[0057] The open-cage configuration benzosuberenyl polyhedral oligomeric silsesquioxane (POSS) of the present application, based on the inorganic open-cage structure of its molecular-level homogeneous dispersion and the moderate cross-linking network formed by low functionality, has a cured product with good flexibility.

[0058] The present application also provides a preparation method of the open-cage configuration benzosuberenyl polyhedral oligomeric silsesquioxane described in the above technical solution, comprising the following steps:

[0059] Mixing a trialkoxysilane coupling agent, an alkali metal hydroxide, water and a first organic solvent to perform a reflux reaction to obtain an open-cage configuration silanol alkali metal salt polyhedral oligomeric silsesquioxane;

[0060] Mixing the open-cage configuration silanol alkali metal salt polyhedral oligomeric silsesquioxane, a vinyl chlorosilane, a first catalyst and a second organic solvent to perform an etherification reaction to obtain a vinyl open-cage polyhedral oligomeric silsesquioxane;

[0061] mixing the vinyl-caged polysilsesquioxane, the benzocyclobutene-based silane compound, a second catalyst and a third organic solvent to perform a hydrosilylation reaction, to obtain a caged benzocyclobutene-based polysilsesquioxane (POSS);

[0062] The structural formulae of the trialkoxysilane coupling agent, the vinyl chlorosilane and the benzocyclobutene-based silane compound are shown in Formula 5, Formula 6 and Formula 7 respectively:

[0063]

[0064] In the present application, the materials and equipment used are commercially available in the art, unless otherwise specified.

[0065] The present application mixes a trialkoxysilane coupling agent, an alkali metal hydroxide, water and a first organic solvent to perform a reflux reaction, to obtain a caged silanol alkali metal salt polysilsesquioxane.

[0066] In the present application, the alkoxy group (OR) in the trialkoxysilane coupling agent (R1Si(OR)3) is preferably a methoxy group or an ethoxy group.

[0067] In the present application, the alkali metal hydroxide (MOH) preferably includes KOH, NaOH or LiOH. The molar ratio of the alkali metal hydroxide and the trialkoxysilane coupling agent is preferably 1:1.5-1:3, and can be 1:2.3 or 1:1.5, to obtain a seven-R1 group tri-silanol alkali metal salt polysilsesquioxane (OP1M3-POSS) having an OP1 caged structure, and an eight-R1 group tetra-silanol alkali metal salt polysilsesquioxane (OP2M4-POSS) having an OP2 caged structure, respectively.

[0068]

[0069] In the present application, the amount of water used is preferably 1-2 times, and more preferably 1.1-1.3 times, the molar amount of the trialkoxysilane coupling agent.

[0070] In the present application, the first organic solvent is preferably a low-boiling organic solvent, and the low-boiling organic solvent preferably includes acetone, tetrahydrofuran or isopropanol.

[0071] In the present application, the concentration of the trialkoxysilane coupling agent in the first organic solvent is preferably 0.5-1.5 mol / L, and more preferably 0.9-1.1 mol / L.

[0072] In the present application, the temperature of the reflux is preferably kept at the micro-boiling point of the solvent, and the time is preferably 4-6h, more preferably 5h. After the reflux, the reaction solution is preferably cooled to room temperature, and then reacted for 15-24h. The solid-liquid separation is preferably filtration. The washing reagent is preferably tetrahydrofuran, and the number of washing is preferably 3. The drying is preferably vacuum drying, and the temperature is preferably 60℃, and the time is preferably 24h.

[0073] After obtaining the open-cage silanol alkali metal salt polyhedral oligomeric silsesquioxane, the present application carries out etherification reaction on the open-cage silanol alkali metal salt polyhedral oligomeric silsesquioxane, vinyl chlorosilane, first catalyst and second organic solvent to obtain vinyl open-cage polyhedral oligomeric silsesquioxane.

[0074] In the present application, the chemical formula of the vinyl chlorosilane is R3R4ClSiCH=CH2 or R3R4ClSiCH2CH=CH2, and R3 and R4 are independently selected from the following structures: H, alkyl, cycloalkyl, cycloalkoxy, alkylthio, alkylamino, alkenylamino, aryl, heteroaryl, substituted alkyl, substituted cycloalkyl, substituted cycloalkoxy, substituted alkylthio, substituted alkylamino, substituted alkenylamino, substituted aryl or substituted heteroaryl. The alkyl is preferably C1-C6 alkyl, the cycloalkyl is preferably C3-C6 cycloalkyl, the cycloalkoxy is preferably 3-7 membered cycloalkoxy, the alkylthio is preferably C1-C6 alkylthio, the alkylamino is preferably C1-C6 alkylamino, the alkenylamino is preferably C2-C6 alkenylamino, the aryl is preferably C6-C 12 The aryl preferably includes benzo C3-C6 cycloalkyl, and the heteroaryl is preferably 5-12 membered heteroaryl, which preferably contains 1-3 N, O or S heteroatoms, and the heteroaryl preferably includes benzo 5-6 membered heterocyclyl. R3 and R4 are both preferably methyl.

[0075] In the present application, the substitution preferably includes halogenation, which preferably includes F, Cl, Br or I substitution.

[0076] In the present application, the molar ratio of alkali metal element to vinyl chlorosilane in the open-cage silanol alkali metal salt polyhedral oligomeric silsesquioxane (OP1M3-POSS / OP2M4-POSS) is preferably 1:2-1:4, more preferably 1:3.

[0077] In the present application, the first catalyst preferably includes organic base, which preferably includes triethylamine, pyridine or diethylamine, more preferably triethylamine.

[0078] In the present application, the molar amount of the organic base is preferably the difference between the molar amount of the vinyl chlorosilane and the molar amount of the vinyl in the vinyl open-cage polyhedral oligomeric silsesquioxane.

[0079] In the present invention, the second organic solvent is preferably an aprotic low-boiling-point solvent, and the aprotic low-boiling-point solvent preferably includes one or more of dichloromethane, tetrahydrofuran and toluene.

[0080] In the present invention, the concentration of the open-cage silanol alkali metal salt polysilsesquioxane in the second organic solvent is preferably 0.05 to 0.15 mol / L, specifically 0.067 mol / L, 0.08 mol / L or 0.1 mol / L.

[0081] In the present invention, the etherification reaction is preferably carried out under an inert gas, preferably nitrogen. The etherification reaction temperature is preferably 0 to 25°C, specifically 20°C, and the reaction time is 24 to 36 hours, specifically 24 hours. The resulting vinyl open-cage polysilsesquioxane has a structural formula as shown in Formula 8 or Formula 9:

[0082]

[0083] In the present invention, after the etherification reaction, the following steps are preferably included: filtering to remove insoluble solids, removing the solvent by rotary evaporation, and washing and drying the obtained solids; the washing reagent is preferably methanol, and the number of washings is preferably 3 times; the drying is preferably vacuum drying, the temperature is preferably 40°C, and the time is preferably 24 hours.

[0084] After obtaining the vinyl open-cage polysilsesquioxane, the present invention mixes the vinyl open-cage polysilsesquioxane, a benzocyclobutenyl silane compound, a second catalyst and a third organic solvent to carry out a hydrosilylation reaction to obtain an open-cage benzocyclobutenyl polysilsesquioxane (POSS).

[0085] In the present invention, the molar ratio of the vinyl group to the benzocyclobutenylsilane compound in the vinyl open-cage polysilsesquioxane is preferably 1:1 to 1:1.5, and specifically 1:1.2.

[0086] In the present invention, the molar concentration of the vinyl open cage polysilsesquioxane (OP1V3-POSS / OP2V4-POSS) in the third organic solvent is preferably 0.05 to 0.5 mol / L, more preferably 0.06 to 0.3 mol / L.

[0087] In the present invention, the second catalyst preferably includes one or more of chloroplatinic acid, chloroplatinic acid-isopropyl alcohol solution, methylvinylsiloxane platinum complex and Karstedt catalyst.

[0088] In the present application, the mass-to-mole ratio of the second catalyst to the benzocyclobutene-based silane compound is preferably 0.025-0.25 g / mol, more preferably 0.05-0.2 g / mol.

[0089] In the present application, the third organic solvent preferably comprises a C1-C 10 alkane-based solvent and / or a C6-C 12 aromatic hydrocarbon-based solvent, more preferably one or more of dichloromethane, trichloromethane, dichloroethane, trichloroethane, n-hexane, cyclohexane, chlorobenzene, toluene, xylene and mesitylene, and specifically toluene.

[0090] In the present application, the hydrosilylation reaction is preferably carried out under protection of an inert gas, preferably nitrogen. The temperature of the hydrosilylation reaction is preferably 90-110°C, and specifically 100°C, and the time is preferably 24-48 h, and more preferably 30-36 h. The obtained exocyclic benzocyclobutene-based polysilsesquioxane is as shown in formula 10 and formula 11:

[0091]

[0092] In the structure of the exocyclic benzocyclobutene-based polysilsesquioxane of formula 10 or formula 11, n is 2 or 3 according to the structure of the vinyl exocyclic polysilsesquioxane described above.

[0093] The present application also provides the use of the exocyclic benzocyclobutene-based polysilsesquioxane described in the above technical solution or the exocyclic benzocyclobutene-based polysilsesquioxane obtained by the above preparation method in the field of wireless communication.

[0094] The present application also provides a cured material obtained by cross-linking and curing the exocyclic benzocyclobutene-based polysilsesquioxane described in the above technical solution or the exocyclic benzocyclobutene-based polysilsesquioxane obtained by the above preparation method.

[0095] In the present application, the preparation method of the resin block comprises the following steps:

[0096] The exocyclic benzocyclobutene-based polysilsesquioxane is melted to obtain a homogeneous viscous liquid;

[0097] The homogeneous viscous liquid is subjected to first cross-linking and curing to obtain a resin block.

[0098] In the present application, the melting is preferably carried out under a protective gas atmosphere; the temperature of the melting is preferably 80-90°C, the time is preferably 2-4 h, and the pressure is preferably -0.08 MPa.

[0099] In the present application, the first cross-linking and curing is preferably carried out under a protective gas atmosphere; the first cross-linking and curing is preferably stage curing, which preferably comprises first stage, second stage and third stage curing, the temperature of the first stage curing is preferably 90℃, and the time is preferably 2h; the temperature of the second stage curing is preferably 210℃, and the time is preferably 2h; the temperature of the third stage curing is preferably 230℃, and the time is preferably 2h. The temperature rising rate from the melting temperature to the temperature of the first stage curing, from the temperature of the first stage curing to the temperature of the second stage curing, and from the temperature of the second stage curing to the temperature of the third stage curing are all preferably 10℃ / min. During the cross-linking and curing, the POSS self-cross-links to form a three-dimensionally cross-linked thermosetting resin bulk material.

[0100] The preparation method of the resin film comprises the following steps:

[0101] The exocyclic benzocyclobutene-based polyhedral oligomeric silsesquioxane is dissolved in an organic solvent, spin coating or drop coating is carried out on a metal substrate, second cross-linking and curing is carried out after the organic solvent is volatilized, the metal substrate is etched in a strong acid aqueous solution, and a resin film is obtained.

[0102] In the present application, the organic solvent preferably comprises one or more of toluene, xylene, trimethylbenzene, diphenyl ether, cyclohexanone, dichloromethane, trichloromethane, acetone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and N-methyl pyrrolidone.

[0103] In the present application, the metal substrate is preferably an acid-etchable metal substrate, which preferably comprises an aluminum plate, a copper plate, an iron plate or a zinc plate.

[0104] In the present application, the temperature at which the organic solvent is volatilized is preferably 100-150℃, and the time is preferably 8-12h.

[0105] In the present application, the second cross-linking and curing is preferably consistent with the method of the first cross-linking and curing, which is not described herein again.

[0106] In the present application, the solubility of the strong acid aqueous solution is preferably 5-15wt%, and more preferably 10wt%.

[0107] The thermosetting resin of the present application is an organic-inorganic hybrid thermosetting material with ultra-low dielectric constant, ultra-low dielectric loss, high heat resistance and flexibility.

[0108] In order to further illustrate the present application, the exocyclic benzocyclobutene-based polyhedral oligomeric silsesquioxane thermosetting resin provided by the present application, the preparation method and application thereof are described in detail below in conjunction with the accompanying drawings and examples, but they should not be understood as limiting the scope of protection of the present application.

[0109] Example 1: Benzocyclobutene-silane (BCB-SiH)

[0110]

[0111] Under the protection of nitrogen, 120.0 mmol of magnesium turnings, 150 mL of anhydrous tetrahydrofuran, 150.0 mmol of dimethylchlorosilane were added to a 250 mL dry three-necked flask, and then 100.0 mmol of 4-bromobenzocyclobutene (Br-BCB) was slowly added at a rate of 1 drop per second; after the addition was completed, the reaction was allowed to proceed overnight at room temperature. After the reaction was completed, the tetrahydrofuran was removed by rotary evaporation and 200 mL of n-hexane was added, and the insoluble inorganic salts were removed by filtration, and the solvent was concentrated and distilled under reduced pressure to obtain 13.2 g of the colorless transparent liquid compound benzocyclobutene-silane (BCB-SiH) with a yield of 81.5%.

[0112] The structure thereof is characterized as:

[0113] 1 H-NMR (400 MHz, Chloroform-d)), δ (ppm): 7.48 (1H), 7.33 (1H), 7.15 (1H), 4.50 (1H), 3.27 (4H), 0.41 (6H).

[0114] 13 C-NMR (100 MHz, Chloroform-d), δ (ppm): 147.45, 145.58, 135.57, 132.43, 127.86, 122.17, 30.04, -3.31.

[0115] 29 Si-NMR (119 MHz, CDCl3), δ (ppm): -16.39.

[0116] Example 2: p-Methylphenylsilane (T-SiH)

[0117]

[0118] Under the protection of nitrogen, 120.0 mmol of magnesium turnings, 150 mL of anhydrous tetrahydrofuran, 150.0 mmol of dimethylchlorosilane were added to a 250 mL dry three-necked flask, and then 100.0 mmol of 4-bromobenzocyclobutene (Br-BCB) was slowly added at a rate of 1 drop per second; after the addition was completed, the reaction was allowed to proceed overnight at room temperature. After the reaction was completed, the tetrahydrofuran was removed by rotary evaporation and 200 mL of n-hexane was added, and the insoluble inorganic salts were removed by filtration, and the solvent was concentrated and distilled under reduced pressure to obtain 13.2 g of the colorless transparent liquid compound benzocyclobutene-silane (BCB-SiH) with a yield of 81.5%.

[0119] The structure is characterized as:

[0120] 1 H-NMR (400 MHz, CDC13), δ (ppm): 7.56 (2H), 7.31 (2H), 4.55 (1H), 2.47 (3H), 0.45 (6H)

[0121] 13 C-NMR (100 MHz, CDC13), δ (ppm): 134.15, 128.78, 29.6, 21.58, -3.64

[0122] 29 Si-NMR (119 MHz, CDC13), δ (ppm): -16.39.

[0123] Example 3: Open-cage heptaphenyltrisilanol polyhedral oligomeric silsesquioxane (OP1B3-POSS)

[0124]

[0125] Into a 500 mL three-necked flask, 230.0 mmol of phenyltrimethoxysilane, 250 mL of anhydrous tetrahydrofuran, 98.6 mmol of sodium hydroxide (NaOH) and 290 mmol of deionized water were sequentially added; the mixture was reacted under reflux for 5 hours and cooled to room temperature for 15 hours. After the reaction was completed, the mixture was filtered, and the filter cake was washed with tetrahydrofuran three times, and dried at 60°C under vacuum for 24 h to obtain 25.3 g of white solid, which was open-cage heptaphenyltrisilanol sodium salt polyhedral oligomeric silsesquioxane (OP1Na3-POSS), with a yield of 78.6%.

[0126] Under nitrogen protection, 90 mmol of vinyl dimethylchlorosilane, 100 mL of anhydrous tetrahydrofuran and 60 mmol of triethylamine were sequentially added to a 250 mL dry three-necked flask, and 10 mmol of open-cage heptaphenyltrisilanol sodium salt polyhedral oligomeric silsesquioxane (OP1Na3-POSS) was added in five portions, and reacted at a constant temperature of 20°C for 24 h. After the reaction was completed, the insoluble solid was removed by filtration, and the solvent was removed by rotary evaporation to obtain a white solid, which was washed with methanol three times, and dried at 40°C under vacuum for 24 h to obtain 5.6 g of open-cage heptaphenyltrivinyl polyhedral oligomeric silsesquioxane (OP1V3-POSS), with a yield of 56.1%.

[0127] Into a 100 mL dry three-necked flask, 3 mmol of exo-octaphenyltetravinyl polyhedral oligomeric silsesquioxane (OP2V4-POSS), 50 mL of toluene and 10.8 mmol of benzocyclobutene-silane (BCB-SiH) were added successively under nitrogen protection, and 5 drops of Karstedt's catalyst was added dropwise to initiate the reaction. The reaction was carried out at 100 °C for 30 h. After the reaction was completed, the excess toluene was removed by concentration under reduced pressure, and the product was purified by silica gel to obtain 4.0 g of white solid, which was exo-octaphenyltetrabenzocyclobutene polyhedral oligomeric silsesquioxane (OP2B4-POSS).

[0128] Figure 1 NMR data of OP2B4-POSS 1 H, 13 C, 29 Si spectrum data, the structure was characterized as:

[0129] 1 H-NMR (400 MHz, Chloroform-d)), δ (ppm): 7.65-7.00 (44H), 3.20 (12H), 0.70-0.48 (12H), 0.29 (18H), 0.19 (18H)

[0130] 13 C-NMR (150 MHz, Chloroform-d), δ (ppm): 147.17, 145.85, 138.13, 132.35, 127.85, 122.26, 135.00-127.00 (40C), 30.43, 30.28, 10.64, 7.63, -0.00, -3.14

[0131] 29 Si-NMR (119 MHz, Chloroform-d), δ (ppm): 11.65, -1.22, -76.13, -78.65.

[0132] Example 4: Exo-octaphenyltetrabenzocyclobutene polyhedral oligomeric silsesquioxane (OP2B4-POSS)

[0133]

[0134] To a 500mL three-necked flask were added 160.0mmol of phenyltrimethoxysilane, 160mL of isopropyl alcohol (IPA), 106.7mmol of sodium hydroxide (NaOH), and 185.0mmol of deionized water. The mixture was reacted at reflux for 5 hours and then cooled to room temperature for 15 hours. After completion of the reaction, the mixture was filtered, and the filter cake was washed three times with tetrahydrofuran. After vacuum drying at 60°C for 24 hours, 24.3g of a white solid, open-cage octaphenyltetrasilanol sodium salt polysilsesquioxane (OP2Na4-POSS), was obtained in an 87.0% yield.

[0135] Under nitrogen, 120 mmol of vinyldimethylsilyl chloride, 150 mL of anhydrous tetrahydrofuran, and 80 mmol of triethylamine were added sequentially to a 250 mL dry three-necked flask. 10 mmol of open-cage octaphenyltetrasilanol sodium salt polysilsesquioxane (OP2Na4-POSS) was then added in five portions. The reaction was maintained at 20°C for 24 hours. After completion of the reaction, the insoluble solid was filtered off, and the solvent was evaporated to obtain a white solid. The solid was washed three times with methanol and dried under vacuum at 40°C for 24 hours to obtain 7.6 g of open-cage octaphenyltetravinyl polysilsesquioxane (OP2V4-POSS), with a yield of 54.3%.

[0136] Under nitrogen, 3 mmol of open-cage octaphenyltetravinyl polysilsesquioxane (OP2V4-POSS), 50 mL of toluene, and 14.4 mmol of benzocyclobutene silyl hydride (BCB-SiH) were added sequentially to a 100 mL dry three-necked flask. Five drops of Karsted catalyst were added dropwise to initiate the reaction. The reaction was allowed to proceed at 100°C for 30 h. After completion of the reaction, the product was concentrated under reduced pressure to remove the excess toluene and purified on silica gel to yield 5.4 g of a white solid, open-cage octaphenyltetrabenzocyclobutenyl polysilsesquioxane (OP2B4-POSS), in an 88.0% yield.

[0137] Figure 2 NMR of OP2B4-POSS 1 H. 13 C. 29 Si spectrum data, its structure is characterized by:

[0138] 1 H-NMR (400MHz, Chloroform-d), δ (ppm): 7.55-6.95 (52H), 3.20 (4H), 0.37 (t, 8H), 0.14 (8H), 0.04 (s, 24H), 0.00 (s, 24H).

[0139] 13C-NMR (150 MHz, Chloroform-d), d (ppm): 147.17, 145.85, 138.13, 132.35, 127.85, 122.26, 135.00-127.00 (40C), 30.43, 30.28, 10.64, 7.63, -0.00, -3.14

[0140] 29 Si-NMR (119 MHz, Chloroform-d), d (ppm): 11.65, -1.22, -76.13, -78.65.

[0141] Comparative Example 1: Closed cage octa-phenalene-based polyhedral oligomeric silsesquioxane (OP0B8-POSS)

[0142]

[0143] Into a 250 mL dry three-necked flask, 200 mL ethyl acetate (EA), 30 mL vinyltrimethoxysilane (VTMS) were added, stirred at 20 °C for 30 min, then 42 mL concentrated hydrochloric acid (HCl) and 18 mL deionized water were added into a 100 mL constant pressure funnel, which was added dropwise into the single-necked flask with constant stirring, and the dropping was completed within 30 min, and the reaction was carried out at 40 °C for 96 h. Then the solvent was removed by filtration to obtain white powder, which was the closed cage octavinyl OP0V8-POSS, 14.08 g, with a yield of 87.6%.

[0144] Under the protection of nitrogen, 100 mL toluene, 10 mmol OP0V8-POSS, 96 mmol BCB-SiH were added into a 250 mL dry three-necked flask, stirred for 30 min, then 5 drops of Karstedt catalyst were added, and the reaction was carried out at 100 °C for 30 h, then concentrated under reduced pressure, and column chromatography was carried out to obtain white powder, 17.4 g, which was OP0B8-POSS, with a yield of 90.0%.

[0145] Figure 3 NMR spectrum of OP0B8-POSS 1 H, 13 C, 29 Si spectrum data, which was structurally characterized as:

[0146] 1 H-NMR (400 MHz, Chloroform-d)), d (ppm): 7.31 (d, J = 7.2 Hz, 1H), 7.17 (s, 8H), 7.17 (d, J = 6.8 Hz, 8H), 3.16 (s, 32H), 0.21 (s, 48H).

[0147] 13C-NMR (150 MHz, Chloroform-d), d (ppm): 147.44, 145.58, 135.58, 132.42, 127.85, 122.16, 29.98, 29.80, 7.35, 4.57, -3.32

[0148] 29 Si-NMR (119 MHz, Chloroform-d), d (ppm): -0.76, -66.39

[0149] Comparative Example 2: Cage-type tetraphenobenzochrysenyl tetramethylphenyl polyhedral oligomeric silsesquioxane (OP0B4T4-POSS)

[0150]

[0151] The preparation of OP0V8-POSS was the same as Comparative Example 1.

[0152] Under nitrogen protection, 100 mL of toluene, 10 mmol of OP0V8-POSS, 40 mmol of BCB-SiH were added to a 250 mL dry three-necked flask, stirred for 30 min, then 5 drops of Karstedt catalyst were added, and reacted at 100°C for 30 hours. Subsequently, 60 mmol of T-SiH was added and reacted at 100°C for another 30 hours, concentrated under reduced pressure, and column chromatography gave white powder 16.0 g, which was OP0B4T4-POSS, with a yield of 85.3%.

[0153] Figure 4 NMR spectrum of OP0B4T4-POSS 1 H, 13 C, 29 Si spectrum data, which was structurally characterized as:

[0154] 1 H-NMR (400 MHz, Chloroform-d)), d (ppm): 7.50-6.96 (28H), 3.16 (s, 32H), 2.32 (12H), 0.7 (16H), 0.5 (16H), 0.22 (48H).

[0155] 13 C-NMR (150 MHz, Chloroform-d), d (ppm): 146.97, 145.60, 138.65, 133.72, 131.92, 128.69, 127.44, 122.02, 29.98, 29.80, 7.35, 4.60, -3.29, -3.42

[0156] 29Si-NMR (119 MHz, Chloroform-d), δ (ppm): -0.70, -1.37, -66.35

[0157] Example 5: Thermoset resin c-OP1B3 based on OP1B3-POSS

[0158] The open-cage OP1B3-POSS obtained in Example 3 was placed in a tetrafluoroethylene mold and was allowed to melt and eliminate bubbles in a vacuum oven at a pressure of -0.08 MPa and a temperature of 90 °C for 2 h, obtaining a homogeneous, viscous POSS melt; subsequently, it was cured in three stages. In the first stage, it was slowly heated to 190 °C at a rate of 10 °C / min for 2 h, in the second stage, it was slowly heated to 210 °C for 2 h, and in the third stage, it was slowly heated to 230 °C for 2 h, obtaining a thermoset resin formed by thermal crosslinking of OP1B3-POSS, designated as c-OP1B3.

[0159] Example 6: Thermoset resin c-OP2B4 based on double open-cage OP2B4-POSS

[0160] The open-cage OP2B4-POSS obtained in Example 4 was placed in a glass mold and was allowed to melt and eliminate bubbles in a vacuum oven at a pressure of -0.08 MPa and a temperature of 90 °C for 2 h, obtaining a homogeneous, viscous POSS melt; subsequently, it was cured in three stages. In the first stage, it was slowly heated to 190 °C for 2 h, in the second stage, it was slowly heated to 210 °C for 2 h, and in the third stage, it was slowly heated to 230 °C for 2 h, obtaining a thermoset resin formed by thermal crosslinking of OP2B4-POSS, designated as c-OP2B4.

[0161] Comparative Example 3: Thermoset resin c-OP0B8 based on closed-cage OP0B8-POSS

[0162] The closed-cage OP0B8-POSS obtained in Comparative Example 1 was placed in a glass mold and was allowed to melt and eliminate bubbles in a vacuum oven at a pressure of -0.08 MPa and a temperature of 120 °C for 2 h, obtaining a homogeneous, viscous POSS melt; subsequently, it was cured in three stages. In the first stage, it was slowly heated to 190 °C for 2 h, in the second stage, it was slowly heated to 210 °C for 2 h, and in the third stage, it was slowly heated to 230 °C for 2 h, obtaining a thermoset resin formed by thermal crosslinking of OP0B8-POSS, designated as c-OP0B8.

[0163] Comparative Example 4: Thermoset resin c-OP0B4T4 based on closed-cage OP0B4T4-POSS

[0164] The closed-cage OP0B4T4-POSS synthesized in Comparative Example 2 was placed in a tetrafluoroethylene mold and placed in a vacuum oven at -0.08 MPa and 120°C for 2 hours to melt and eliminate bubbles, resulting in a homogeneous, viscous POSS melt. This was then cured in three stages. The first stage involved slowly heating the temperature to 190°C and holding it for 2 hours; the second stage involved slowly heating the temperature to 210°C and holding it for 2 hours; and the third stage involved slowly heating the temperature to 230°C and holding it for 2 hours. This resulted in a thermosetting resin formed by thermally crosslinking the OP0B4T4-POSS, named c-OP0B4T4.

[0165] Comparative Example 5: Bismaleimide resin c-BMI

[0166] Take 4g of commercial diphenylmethane bismaleimide and 3g of diallyl bisphenol A and prepolymerize them at 120°C for 2 hours to form a uniform and transparent prepolymer; then, pour the prepolymer into a tetrafluoroethylene mold and place it in a vacuum oven to degas and remove bubbles. The temperature is raised to 150°C, 180°C, and 220°C and cured for 2 hours respectively. The resulting thermosetting resin is named c-BMI.

[0167] Comparative Example 6: Cyanate resin c-BADCy

[0168] 10 g of commercial bisphenol A cyanate resin was prepolymerized at 120°C for 1 hour to form a uniform prepolymer. The prepolymer was then poured into a glass mold and placed in a vacuum oven for degassing and removal of bubbles. The prepolymer was then cured at 150°C, 180°C, and 220°C for 2 hours each, and at 240°C for 4 hours. The resulting thermosetting resin was named c-BADCy.

[0169] Test Example 1

[0170] The dielectric constant and dielectric loss of the cured materials obtained in Examples 5 to 6 and Comparative Examples 3 to 6 were tested at 25°C and 1 Hz to 1 MHz using a Concept 80 broadband dielectric spectrometer. The measurement results are shown in Tables 1 and Figures 5-6 As shown in Table 1, the dielectric properties of open-cage benzocyclobutene-based POSS resin and comparative resin at 1 MHz are shown; Figure 5 The broadband dielectric constant data of open-cage benzocyclobutene-based POSS resin and comparative resin are shown; Figure 6 The broadband dielectric loss data of open-cage benzocyclobutene-based POSS resin and comparative resin are shown.

[0171] Table 1 Dielectric properties of open-cage benzocyclobutene-based POSS resin and comparative resin at 1 MHz

[0172] Dielectric constant (1 MHz) Dielectric loss (1 MHz) Example 5, c-OP1B3 2.10 0.0020 Example 6, c-OP2B4 1.96 0.0018 Comparative Example 3, c-OP0B8 2.16 0.0023 Comparative Example 4, c-OP0B4T4 2.17 0.0027 Comparative Example 5, c-BMI 3.31 0.013 Comparative Example 6, c-BADCy 3.03 0.007

[0173] From the above test results, it can be seen that the thermosetting resin based on the open-cage benzocyclobutene-based POSS has a lower dielectric constant than the closed-cage structure-cured thermosetting resin. At the same time, due to the homogeneous hybridization at the molecular level, this type of resin does not undergo phase separation, avoiding the interface polarization of the organic-inorganic hybrid material, and its dielectric loss is maintained at 2×10 -3 At the same time, compared with traditional bismaleimide resins and cyanate ester resins, this type of resin has a dielectric constant as low as about 2.0 at 1MHz, and the dielectric loss value is 1 / 6 of that of bismaleimide resin.

[0174] Test Example 2

[0175] Thermogravimetric curves of the cured materials obtained from Examples 5 to 6 and Comparative Examples 3 to 6 were tested. Figure 7 As shown in the figure, due to the presence of high surface energy and high bond energy Si-O, the open-cage c-OP1B3 and c-OP2B4 resins have better thermal stability than commercial resins (c-BMI and c-BADCy). Although their thermal stability is reduced compared to the more highly cross-linked closed-cage c-OP0B8, they have comparable high thermal stability to the closed-cage c-OP0B4T4 resin with a similar degree of cross-linking, with their 5% thermal weight loss temperature still reaching above 450°C.

[0176] Test Example 3

[0177] The Young's modulus of the cured materials obtained in Examples 5 to 6 and Comparative Examples 3 to 6 was tested at 25°C using a nanoindentation test system. Figure 8 As shown in the figure, it is shown that the flexible open cage structure and low functionality (3 or 4) give the cured product of the open cage POSS resin a lower Young's modulus, indicating that it has better flexibility. Therefore, it can not only be prepared into a solid bulk material by casting, but also be prepared into a flexible thin film material (film thickness of about 60 μm) by spin coating or drop coating. Figure 9 As shown in the figure, the closed-cage c-OP0B8 can only be prepared into bulk samples and is difficult to be prepared into complete thin film samples; while the open-cage c-OP1B3 and c-OP2B4 can be prepared not only into solid bulk materials but also into flexible thin film materials.

[0178] The organic-inorganic thermosetting resin material prepared by thermal crosslinking open-cage polysilsesquioxane (POSS) not only has the characteristics of ultra-low dielectric constant (1.96) and low dielectric loss value (~0.002); at the same time, its 5% thermal weight loss temperature reaches above 450°C. These properties are far superior to currently commercial low-dielectric thermosetting resin materials (such as bismaleimide resin and cyanate resin).

[0179] Although the above embodiments have been described in detail, it should be understood that the detailed description is merely illustrative of the present application, not completely describing all the embodiments of the present application. Based on the embodiments of the present application, other embodiments can be obtained without creative labor, which are also within the scope of the present application.

Claims

1. An open-cage benzocyclobutenyl polysilsesquioxane, characterized in that: The structural formula is shown in Formula 1 or Formula 2: In the formula, R1 is selected from the following structures: phenyl, cyclohexyl, n-pentyl, trifluoro-n-pentyl or methyl; R2 is selected from the following structures: R3, R4, R5 and R6 are independently selected from the following structures: H, alkyl, cycloalkyl, cycloalkoxy, alkylthio, alkylamino, alkenylamino, aryl, heteroaryl, substituted alkyl, substituted cycloalkyl, substituted cycloalkoxy, substituted alkylthio, substituted alkylamino, substituted alkenylamino, substituted aryl or substituted heteroaryl.

2. The open-cage benzocyclobutenyl polysilsesquioxane according to claim 1, wherein In R3, R4, R5 and R6, the alkyl group is a C1-C6 alkyl group, the cycloalkyl group is a C3-C6 cycloalkyl group, the cycloalkoxy group is a 3-7 membered cycloalkoxy group, the alkylthio group is a C1-C6 alkylthio group, the alkylamino group is a C1-C6 alkylamino group, the alkenylamino group is a C2-C6 alkenylamino group, and the aryl group is a C6-C 12 Aryl, the aryl includes benzo C3-C6 cycloalkyl, the heteroaryl is a 5-12 membered heteroaryl, the 5-12 membered heteroaryl contains 1-3 N, O or S heteroatoms, and the heteroaryl includes benzo 5-6 membered heterocyclic group.

3. The open-cage benzocyclobutenyl polysilsesquioxane according to claim 1 or 2, characterized in that The structural formula of the open-cage benzocyclobutenyl polysilsesquioxane is shown in Formula 3 or Formula 4:

4. The method for preparing the open-cage benzocyclobutenyl polysilsesquioxane according to any one of claims 1 to 3, characterized in that: The following steps are involved: Mixing a trialkoxysilane coupling agent, an alkali metal hydroxide, water and a first organic solvent and subjecting them to a reflux reaction to obtain an open-cage silanol alkali metal salt polysilsesquioxane; The open-cage silanol alkali metal salt polysilsesquioxane, vinyl chlorosilane, a first catalyst and a second organic solvent are mixed to carry out an etherification reaction to obtain a vinyl open-cage polysilsesquioxane; The vinyl open-cage polysilsesquioxane, the benzocyclobutenyl silane compound, the second catalyst and the third organic solvent are mixed to carry out a hydrosilylation reaction to obtain the open-cage benzocyclobutenyl polysilsesquioxane; The structural formulas of the trialkoxysilane coupling agent, vinylchlorosilane, and benzocyclobutenylsilane compound are shown in Formula 5, Formula 6, and Formula 7, respectively:

5. The preparation method according to claim 4, characterized in that The alkoxy group in the trialkoxysilane coupling agent is a methoxy group or an ethoxy group.

6. The preparation method according to claim 4 or 5, characterized in that The molar ratio of the alkali metal hydroxide to the trialkoxysilane coupling agent is 1:1.5 to 1:

3.

7. The preparation method according to claim 4, characterized in that The molar ratio of the alkali metal element to vinyl chlorosilane in the open-cage silanol alkali metal salt polysilsesquioxane is 1:2 to 1:

4.

8. The preparation method according to claim 4, characterized in that The molar ratio of the vinyl group to the benzocyclobutenyl silane compound in the vinyl open-cage polysilsesquioxane is 1:1 to 1:1.

5.

9. Use of the open-cage benzocyclobutenyl polysilsesquioxane according to any one of claims 1 to 3 or the open-cage benzocyclobutenyl polysilsesquioxane obtained by the preparation method according to any one of claims 4 to 8 in the field of telecommunications.

10. A solidified material, characterized in that: The curing material is obtained by cross-linking and curing the open-cage benzocyclobutenyl polysilsesquioxane according to any one of claims 1 to 3 or the open-cage benzocyclobutenyl polysilsesquioxane obtained by the preparation method according to any one of claims 4 to 8.

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