Asymmetric divinyl benzyl fluorene, thermosetting hydrocarbon resin, thermosetting cross-linked resin, and preparation methods and applications of asymmetric divinyl benzyl fluorene, thermosetting hydrocarbon resin and thermosetting cross-linked resin

Abstract

The invention belongs to the technical field of high-frequency and high-speed substrate materials. The invention provides asymmetric divinyl benzyl fluorene (9-(2-vinyl benzyl)-9 '-(4-vinyl benzyl)-9H-fluorene, o, p-BVBF), thermosetting hydrocarbon resin of the asymmetric divinyl benzyl fluorene and a preparation method and application of the thermosetting hydrocarbon resin, and simultaneously provides thermosetting hydrocarbon resin of o, p-BVBF and symmetric divinyl benzyl fluorene (9, 9'-bis (4-vinyl benzyl)-9H-fluorene, p, p-BVBF) and thermosetting hydrocarbon resin of o, p-BVBF and p, p-BVBF and / or p, p-BVBF. The invention relates to thermosetting cross-linked resin taking p-BVBF as a cross-linking agent and terminal alkenyl polyphenyl ether as well as a preparation method and application of the thermosetting cross-linked resin. The thermosetting hydrocarbon resin and the thermosetting cross-linked resin provided by the invention have very low dielectric constant and dielectric loss angle tangent and very high glass transition temperature, and have very good application prospects as the resin of the high-frequency and high-speed substrate.

Description

Technical Field

[0001] The invention belongs to the technical field of high-frequency and high-speed substrate materials, and specifically relates to an asymmetric divinylbenzylfluorene, a thermosetting hydrocarbon resin, a thermosetting cross-linked modified polyphenylene ether resin, and a preparation method and application thereof. Background Art

[0002] With the rapid development of 5G / 6G communications, artificial intelligence, AR / VR, satellite navigation and autonomous driving, electronic products require high frequency, high speed and greater capacity to transmit sound, video and data. At the same time, electronic products tend to be light, thin and small. In order to maintain higher transmission rates and signal integrity, the laminated resin material of the printed circuit board (PCB), the core component of electronic products, needs to have a lower dielectric constant, lower dielectric loss tangent, higher glass transition temperature and stronger peel strength. Therefore, further improving the dielectric and thermomechanical properties of resin materials is a key technical problem that needs to be solved urgently.

[0003] Epoxy resin is the main resin material used for printed circuit boards due to its low cost, but its relatively high dielectric constant and high dielectric loss tangent make it difficult to achieve a suitable low dielectric loss tangent under high-frequency signals, and it is difficult to achieve the requirements of high-speed signal transmission. Fluororesins represented by polytetrafluoroethylene have the properties of low dielectric constant and low dielectric loss tangent, but they are thermoplastic resins and are difficult to process and mold to achieve the preparation of multi-layer and light, thin, and small printed circuit boards. Modified polyphenylene ether (mPPO) terminated with low molecular weight vinylbenzyl or acryl has a lower dielectric constant and dielectric loss tangent. The cross-linked polyphenylene ether resin cross-linked with mPPO and diene (such as 1,2-bis(4-vinylphenyl)ethane, BVPE) has high thermomechanical properties and has been used as a laminate resin material for high-end printed circuit boards (PCBs).

[0004] 9,9-Disubstituted fluorenyl hydrocarbon derivatives are widely used as materials for microelectronic devices due to their unique Cardo structure, low dielectric constant and low dielectric loss tangent, high refractive index and transparency, and other good photoelectric properties, as well as good heat resistance, moisture resistance and good solubility in organic solvents.

[0005] Japanese Patent JP2003283076A discloses a mixture prepared by reacting vinylbenzyl chloride (a mixture of meta- and para-isomers with a mass ratio of 1:1) and allyl chloride with fluorene. The dielectric constant (5 GHz) of its thermosetting resin is 4.0, and the dielectric loss tangent (5 GHz) is 0.0035. Its dielectric constant and dielectric loss tangent are obviously too high. At the same time, the presence of allyl groups on the 9-fluorenyl group results in a relatively low glass transition temperature of the composition. Patent WO2022207741A1 discloses a thermosetting resin of vinylbenzylindene and a mixture of 9,9-divinylbenzyl-9H-fluorene containing the meta-isomer. Its dielectric loss tangent (10 GHz) is 0.00089. For the resin of high-frequency and high-speed substrates, its dielectric constant and dielectric loss tangent are still on the high side. At the same time, in Patent WO2022207741A1, in order to increase the glass transition temperature, bismaleimide is used as a crosslinking agent. Bismaleimide contains polar groups, which can increase the glass transition temperature but will lead to an increase in the dielectric loss tangent. CN1501899A discloses a mixture of meta- and para-isomers of 9,9-bis(vinylbenzyl)-9H-fluorene with a melting point of 142 °C prepared by reacting a mixture of vinylbenzyl chloride (meta- and para-isomers with a mass ratio of 1:1) with fluorene. The dielectric loss tangent of its thermosetting resin at 1 MHz is 0.0013, and its dielectric loss tangent is obviously too high and is not suitable as a resin material for high-frequency and high-speed substrates.

[0006] In order to meet the requirements of high-frequency and high-speed transmission of the new generation of printed circuit laminates, further reducing the dielectric constant and dielectric loss tangent of the resin material of the printed circuit board and further increasing the glass transition temperature are the key technical problems to be solved urgently at present. Summary of the Invention

[0007] In view of this, the present invention provides an asymmetric divinylbenzylfluorene, a thermosetting hydrocarbon resin using the asymmetric divinylbenzylfluorene as a raw material, its preparation method and application; a thermosetting hydrocarbon resin using the asymmetric divinylbenzylfluorene and / or symmetric divinylbenzylfluorene as a raw material, its preparation method and application; and a thermosetting crosslinked polyphenylene ether resin crosslinked with the asymmetric divinylbenzylfluorene, symmetric divinylbenzylfluorene or a mixture of both as a crosslinking agent and a terminal vinyl polyphenylene ether, its preparation method and application. Since the asymmetric divinylbenzylfluorene (9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene, o,p-BVBF) provided by the present invention is a non-polar all-hydrocarbon compound, and the two asymmetric substituents on the 9-fluorenyl group form a rigid cardo structure, the thermosetting hydrocarbon resin and the thermosetting crosslinked polyphenylene ether resin have a small dielectric loss tangent, a low dielectric constant and a high glass transition temperature, and have good application prospects as resin materials for high-frequency and high-speed substrates.

[0008] To solve the above technical problems, the present invention provides an asymmetric divinylbenzylfluorene, which is 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene having the structure shown in Formula 1:

[0009]

[0010] The thermal analysis melting endothermic peak of the 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene is 169-175 °C, and it has a monoclinic crystal system with a space group of P2 1 / c.

[0011] The present invention also provides a preparation method of the asymmetric divinylbenzylfluorene described in the above technical solution, including the following steps:

[0012] Mix fluorene, a basic reagent, an inhibitor, and a polar aprotic solvent to obtain a fluorene-containing mixed system;

[0013] Dropwise add 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing mixed system in sequence or dropwise add a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing mixed system to carry out a nucleophilic substitution reaction to obtain the asymmetric divinylbenzylfluorene.

[0014] Preferably, the basic reagent includes one or more of alkali metal hydroxides, alkali metal alkoxides, sodium hydride, and potassium hydride;

[0015] The inhibitor includes one or several of nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butylcatechol, 2,2,6,6-tetramethylpiperidine 1-oxyl, and 2,2,6,6-tetramethyl-4-hydroxypiperidine 1-oxyl;

[0016] The polar aprotic solvent includes dimethyl sulfoxide, sulfolane, N,N-dimethylformamide, N,N-diethylformamide, acetonitrile, or hexamethylphosphoramide;

[0017] The molar ratio of the fluorene to the basic reagent is 1:1.8-5;

[0018] The molar ratio of the 2-vinylbenzyl chloride to the 4-vinylbenzyl chloride is 2-6:4-8;

[0019] The total molar amount of the 2-vinylbenzyl chloride and the 4-vinylbenzyl chloride and the molar ratio of the fluorene is 1.8-2.2:1.

[0020] Preferably, the temperature of the nucleophilic substitution reaction is 20-50 °C, and the time is 2-8 h.

[0021] The present invention also provides a preparation method of the asymmetric divinylbenzylfluorene described in the above technical solution, which comprises the following steps:

[0022] Mix fluorene, a basic reagent, an inhibitor, a phase transfer catalyst and a solvent to obtain a fluorene-containing phase transfer catalytic system;

[0023] Dropwise add 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing phase transfer catalytic system in sequence or dropwise add a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing phase transfer catalytic system, and carry out a nucleophilic substitution reaction under phase transfer catalytic conditions to obtain the asymmetric divinylbenzylfluorene.

[0024] Preferably, the basic reagent includes alkali metal hydroxides and / or alkali metal alcoholates;

[0025] The inhibitor includes one or more of nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butylcatechol, 2,2,6,6-tetramethylpiperidine nitroxide and 2,2,6,6-tetramethyl-4-hydroxypiperidine nitroxide;

[0026] The phase transfer catalyst includes one or more of quaternary ammonium salts, quaternary phosphonium salts and polyethylene glycol;

[0027] The mass of the phase transfer catalyst is 5-25% of the mass of fluorene;

[0028] The molar ratio of fluorene to the basic reagent is 1:1.8-5;

[0029] The molar ratio of 2-vinylbenzyl chloride to 4-vinylbenzyl chloride is 2-6:4-8;

[0030] The total molar amount of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride and the molar ratio of fluorene is 1.8-2.2:1.

[0031] Preferably, the temperature of the nucleophilic substitution reaction under phase transfer catalytic conditions is 25-75 °C and the time is 8-18 h.

[0032] The present invention also provides a thermosetting resin, including a thermosetting hydrocarbon resin and / or a thermosetting cross-linked resin. The thermosetting hydrocarbon resin includes a thermosetting hydrocarbon resin prepared from 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene as a preparation raw material and / or a thermosetting hydrocarbon resin prepared from 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and 9,9'-bis(4-vinylbenzyl)-9H-fluorene as preparation raw materials;

[0033] The thermosetting crosslinked resin includes a thermosetting crosslinked resin prepared from a crosslinking agent and a terminal vinyl polyphenylene ether as raw materials; the crosslinking agent includes 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and / or 9,9'-bis(4-vinylbenzyl)-9H-fluorene; the terminal vinyl polyphenylene ether has a structure shown in any one of Formulas 2 to 5;

[0034]

[0035] The 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene is the asymmetric divinylbenzyl fluorene described in the above technical solution or the asymmetric divinylbenzyl fluorene prepared by the preparation method described in the above technical solution.

[0036] The present invention also provides a preparation method of the thermosetting resin described in the above technical solution, including the following steps:

[0037] Dissolve the raw materials and the initiator in toluene to obtain a mixed solution;

[0038] After removing toluene from the mixed solution, perform melt thermal curing to obtain the thermosetting resin.

[0039] The present invention also provides an application of the thermosetting resin described in the above technical solution or the thermosetting resin prepared by the preparation method described in the above technical solution as a resin material for a high-frequency and high-speed substrate.

[0040] The present invention provides an asymmetric divinylbenzyl fluorene having a structure shown in Formula 1: The thermal analysis melting endothermic peak of the 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene is 169 to 175 °C, having a monoclinic crystal system and a space group of P2 1 / c. The divinylbenzyl fluorene (9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF)) provided by the present invention has an asymmetric structure and is a non-polar all-carbon hydrogen compound. At the same time, the two asymmetric substituents of the 9-position fluorene group form a rigid cordo structure, so that the thermosetting resin prepared from the asymmetric divinylbenzyl fluorene provided by the present invention has the characteristics of small dielectric loss tangent, low dielectric constant, high glass transition temperature, and easy processing, and can be used as a resin material for a high-frequency and high-speed substrate. Description of the Drawings

[0041] Figure 1 It is a schematic diagram of the process for synthesizing asymmetric divinylbenzyl fluorene by nucleophilic substitution reaction;

[0042] Figure 2HPLC spectrum of o,p-BVBF prepared in Example 1;

[0043] Figure 3 For o,p-BVBF prepared in Example 1 1 HNMR spectrum;

[0044] Figure 4 For o,p-BVBF prepared in Example 1 13 CNMR spectrum;

[0045] Figure 5 Thermal analysis DSC spectrum of o,p-BVBF prepared in Example 1;

[0046] Figure 6 Single crystal structure diagram of o,p-BVBF prepared in Example 1;

[0047] Figure 7 Unit cell packing diagram of o,p-BVBF prepared in Example 1. Detailed implementation mode

[0048] The present invention synthesizes an asymmetric divinylbenzylfluorene, which is 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) having the structure shown in Formula 1:

[0049]

[0050] The endothermic melting peak of the 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene is 169-175 °C, and it has a monoclinic system with a space group of P2 1 / c.

[0051] In the present invention, the "asymmetric" in the "asymmetric divinylbenzylfluorene" means that there are different substituents at the 9-position of the fluorene group.

[0052] As a specific implementation mode of the present invention, the endothermic melting peak of the 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene is 169-175 °C, and it can be 171-173 °C; the purity (HPLC) of the asymmetric divinylbenzylfluorene can be >98.5%.

[0053] The present invention synthesizes the 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) by two methods.

[0054] The present invention also provides a first preparation method of the asymmetric divinylbenzylfluorene described in the above technical solution, including the following steps:

[0055] Mix fluorene, a basic reagent, an inhibitor, and a polar aprotic solvent to obtain a fluorene-containing mixed system;

[0056] Dropwise add 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing mixed system in sequence, or dropwise add a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing mixed system, and carry out a nucleophilic substitution reaction to obtain the asymmetric divinylbenzyl fluorene.

[0057] As a specific embodiment of the present invention, the basic reagent may include one or more of alkali metal hydroxides, alkali metal alkoxides, sodium hydride, and potassium hydride, and may specifically be a mixture of alkali metal hydroxides and alkali metal alkoxides, alkali metal hydroxides, alkali metal alkoxides, sodium hydride, or potassium hydride; the alkali metal hydroxide may be sodium hydroxide or potassium hydroxide; the alkali metal alkoxide may be potassium tert-butoxide or sodium tert-butoxide; the molar ratio of fluorene to the basic reagent may be 1:1.8 to 5, and may also be 1:2 to 4.

[0058] As a specific embodiment of the present invention, the inhibitor may include one or several of nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butylcatechol, 2,2,6,6-tetramethylpiperidine 1-oxyl, and 2,2,6,6-tetramethyl-4-hydroxypiperidine 1-oxyl (inhibitor 701), and may specifically be nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butylcatechol, 2,2,6,6-tetramethylpiperidine 1-oxyl, or inhibitor 701; the dosage of the inhibitor may be 0.01 to 0.5% of the mass of vinylbenzyl chloride, and may also be 0.1 to 0.4%; the vinylbenzyl chloride is 2-vinylbenzyl chloride and 4-vinylbenzyl chloride.

[0059] As a specific embodiment of the present invention, the polar aprotic solvent includes dimethyl sulfoxide, sulfolane, N,N-dimethylformamide, N,N-diethylformamide, acetonitrile, or hexamethylphosphoramide; the present invention has no special limitation on the dosage of the polar aprotic solvent as long as the materials can be mixed evenly.

[0060] The present invention has no special requirements for the mixing of fluorene, a basic reagent, an inhibitor, and a polar aprotic solvent, as long as they can be mixed evenly.

[0061] In the present invention, 2-vinylbenzyl chloride is first added dropwise to the fluorene-containing mixed system to generate a mono-substituted 9-(2-vinylbenzyl)fluorene intermediate, and then 4-vinylbenzyl chloride is added dropwise for reaction; compared with directly adding a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride dropwise, the yield of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) is significantly increased; if 4-vinylbenzyl chloride is added dropwise first and then 2-vinylbenzyl chloride is added for reaction, 9,9'-bis-(4-vinylbenzyl)fluorene (p,p-BVBF) will be mainly obtained, while the yield of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) will be very low; this is because the steric hindrance of 2-vinylbenzyl chloride in the reaction is much larger than that of 4-vinylbenzyl chloride, and it is difficult to introduce 2-vinylbenzyl when there is already a 4-vinylbenzyl on the 9-position fluorene group.

[0062] As a specific embodiment of the present invention, the molar ratio of 2-vinylbenzyl chloride to 4-vinylbenzyl chloride can be 2 to 6:4 to 8, specifically 2:8, 3:7, 4:6, 5:5 or 6:4; the total molar amount of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride and the molar ratio of fluorene can be 1.8 to 2.2:1, specifically 2:1.

[0063] As a specific embodiment of the present invention, the temperature of the nucleophilic substitution reaction can be 20 to 50 °C or 30 to 40 °C; the time of the nucleophilic substitution reaction can be 2 to 8 h, or 3 to 7 h. As a specific embodiment of the present invention, the nucleophilic substitution reaction can be carried out under stirring conditions. The present invention has no special limitation on the stirring.

[0064] As a specific embodiment of the present invention, after the nucleophilic substitution reaction, it may further include:

[0065] Mix the system after the nucleophilic substitution reaction with ice water and then perform solid-liquid separation to obtain a solid;

[0066] Wash the solid with water and then perform pulping, filtration, recrystallization and drying in sequence to obtain the asymmetric divinylbenzyl fluorene.

[0067] As a specific embodiment of the present invention, the volume ratio of the system after the nucleophilic substitution reaction to ice water can be 3:8 to 12, and can also be 3:10 to 11; the solid-liquid separation can be filtration; the present invention has no special requirements for the number of water washing times, as long as the pH value of the filtrate after water washing is neutral. As a specific embodiment of the present invention, the solvent for pulping can be an alcohol solvent; the alcohol solvent can include methanol, ethanol or isopropanol; the temperature of the pulping can be 0 to 40 °C, and can also be 10 to 30 °C. The present invention has no special limitation on the filtration, and the conventional method in the art can be adopted. As a specific embodiment of the present invention, the solvent for recrystallization can include toluene, ethylbenzene, xylene or cumene; the drying can be vacuum drying, and the temperature of the vacuum drying can be 70 to 90 °C, and can also be 75 to 80 °C; the present invention has no special requirements for the time of the vacuum drying, as long as the solvent can be removed.

[0068] The present invention also provides a second preparation method of the asymmetric divinylbenzylfluorene described in the above technical solution, comprising the following steps:

[0069] Mix fluorene, a basic reagent, a polymerization inhibitor, a phase transfer catalyst and a solvent to obtain a fluorene-containing phase transfer catalytic system;

[0070] Dropwise add 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing phase transfer catalytic system in sequence or dropwise add a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to the fluorene-containing phase transfer catalytic system, and carry out a nucleophilic substitution reaction under phase transfer catalytic conditions to obtain the asymmetric divinylbenzylfluorene.

[0071] As a specific embodiment of the present invention, the basic reagent can include alkali metal hydroxides and / or alkali metal alkoxides; specifically, it can be a mixture of alkali metal hydroxides and alkali metal alkoxides, alkali metal hydroxides or alkali metal alkoxides; the alkali metal hydroxides can be sodium hydroxide, potassium hydroxide; the alkali metal alkoxides can be potassium tert-butoxide, sodium tert-butoxide; the molar ratio of fluorene to the basic reagent can be 1:1.8 to 5, and can also be 1:2 to 4.

[0072] As a specific embodiment of the present invention, the polymerization inhibitor may include one or more of nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butylcatechol, 2,2,6,6-tetramethylpiperidine-n-oxide and 2,2,6,6-tetramethyl-4-hydroxypiperidine-n-oxide (inhibitor 701), specifically nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butylcatechol, 2,2,6,6-tetramethylpiperidine-n-oxide or inhibitor 701; the dosage of the polymerization inhibitor is 0.01-0.5% of the mass of vinylbenzyl chloride, and may also be 0.1-0.4%; the vinylbenzyl chloride is 2-vinylbenzyl chloride and 4-vinylbenzyl chloride.

[0073] As a specific embodiment of the present invention, the phase transfer catalyst may include one or more of quaternary ammonium salts, quaternary phosphonium salts and polyethylene glycols, specifically quaternary ammonium salts, quaternary phosphonium salts or polyethylene glycols; the quaternary ammonium salt may be tetrabutylammonium bromide (TBAB), tetrabutylammonium chloride (TBAC), benzyltriethylammonium bromide (BTEAB), benzyltriethylammonium chloride (BTEAC), hexadecyltriethylammonium bromide (HTEAB) or hexadecyltriethylammonium chloride (HTEAC); the quaternary phosphonium salt may be hexadecyltributylphosphonium bromide (HTBPB), hexadecyltributylphosphonium chloride (HTBPC), tetrabutylphosphonium bromide (TBPB), tetrabutylphosphonium chloride (TBPC), tetraphenylphosphonium bromide (TPPB) or tetraphenylphosphonium chloride (TPPC); the polyethylene glycol may be PEG-400, PEG-600 or PEG-800. As a specific embodiment of the present invention, the mass of the phase transfer catalyst may be 5-25% of the mass of fluorene, and may also be 10-20%.

[0074] As a specific embodiment of the present invention, the nucleophilic substitution reaction under the phase transfer catalytic conditions may be a liquid-liquid phase transfer catalytic nucleophilic substitution reaction or a solid-liquid phase transfer catalytic nucleophilic substitution reaction.

[0075] As a specific embodiment of the present invention, when the nucleophilic substitution reaction under the phase transfer catalytic conditions is a reaction under solid-liquid phase transfer catalytic conditions, the solvent may be an organic solvent, and the organic solvent may include dimethyl sulfoxide, sulfolane, N,N-dimethylformamide, N,N-diethylformamide, acetonitrile or hexamethylphosphoramide;

[0076] As a specific embodiment of the present invention, when the nucleophilic substitution reaction under the phase transfer catalysis conditions is a reaction under liquid-liquid phase transfer catalysis conditions, the solvent can be a mixture of an aromatic hydrocarbon and water or a mixture of an alkane and water; the aromatic hydrocarbon can be toluene, xylene, ethylbenzene or isopropylbenzene; the alkane can be n-hexane, n-heptane, cyclohexane, methylcyclopentane or petroleum ether.

[0077] In the present invention, 2-vinylbenzyl chloride is first added dropwise to generate a monosubstituted 9-(2-vinylbenzyl)fluorene intermediate, and then 4-vinylbenzyl chloride is added dropwise for reaction. Compared with directly adding a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride, the yield of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) is significantly increased; if 4-vinylbenzyl chloride is added dropwise first and then 2-vinylbenzyl chloride is added for reaction, 9,9'-bis-(4-vinylbenzyl)fluorene (p,p-BVBF) will be mainly obtained, and the yield of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) will be very low; this is because the steric hindrance of 2-vinylbenzyl chloride in the reaction is much larger than that of 4-vinylbenzyl chloride. When there is already a 4-vinylbenzyl group on the 9-position fluorene group, it is difficult to introduce a 2-vinylbenzyl group; therefore, adding 2-vinylbenzyl chloride first and then adding 4-vinylbenzyl chloride for reaction after a period of time is beneficial to improving the yield of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF).

[0078] As a specific embodiment of the present invention, the molar ratio of 2-vinylbenzyl chloride to 4-vinylbenzyl chloride can be 2 to 6:4 to 8, specifically 2:8, 3:7, 4:6, 5:5 or 6:4; the molar ratio of the total molar amount of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride to fluorene can be 1.8 to 2.2:1, specifically 2:1.

[0079] As a specific embodiment of the present invention, the temperature of the nucleophilic substitution reaction under the phase transfer catalysis conditions can be 25 to 75 °C, and can also be 30 to 70 °C; the time of the nucleophilic substitution reaction under the phase transfer catalysis conditions can be 8 to 18 h, and can also be 10 to 15 h. As a specific embodiment of the present invention, the reaction under the phase transfer catalysis conditions must be carried out under good stirring conditions.

[0080] As a specific embodiment of the present invention, after the nucleophilic substitution reaction under the phase transfer catalysis conditions, it may further include:

[0081] After distilling off the solvent from the system after the nucleophilic substitution reaction under the phase transfer catalysis conditions, water and toluene are added for extraction, and the organic phase is taken.

[0082] The organic phase is concentrated and then successively washed, slurried, filtered, recrystallized, and dried to obtain the asymmetric divinylbenzylfluorene.

[0083] As a specific embodiment of the present invention, the volume ratio of water to toluene for extraction can be 1:0.8 - 1.2, or can also be 1:1; the concentration can be vacuum distillation, and the present invention has no special requirements for the vacuum distillation, as long as the solvent can be removed. As a specific embodiment of the present invention, the solvent for washing can be a saturated ammonium chloride solution, and the present invention has no special requirements for the number of washing times, as long as the pH value of the washing liquid after washing is neutral. As a specific embodiment of the present invention, the solvent for slurrying can be an alcohol solvent with less than five carbons; the alcohol solvents with less than five carbons include methanol, ethanol, or isopropanol; the temperature for slurrying can be 0 - 40°C, or can also be 10 - 30°C. The present invention has no special limitations on the filtration, and a conventional method in the art can be used. As a specific embodiment of the present invention, the solvent for recrystallization can include toluene, ethylbenzene, xylene, or isopropylbenzene; the drying can be vacuum drying, and the temperature for the vacuum drying can be 70 - 90°C, or can also be 75 - 80°C; the present invention has no special requirements for the time of the vacuum drying, as long as the solvent can be removed.

[0084] Figure 1 It is a schematic diagram of the process for synthesizing asymmetric divinylbenzylfluorene through a nucleophilic substitution reaction.

[0085] The present invention also provides a thermosetting resin, including a thermosetting hydrocarbon resin and / or a thermosetting crosslinked resin. The thermosetting hydrocarbon resin includes a thermosetting hydrocarbon resin prepared from 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene as a raw material and / or a thermosetting hydrocarbon resin prepared from 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and 9,9'-bis(4-vinylbenzyl)-9H-fluorene as raw materials;

[0086] The thermosetting crosslinked resin includes a thermosetting crosslinked resin prepared from a crosslinking agent and a terminal alkenyl polyphenylene ether as raw materials; the crosslinking agent includes 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and / or 9,9'-bis(4-vinylbenzyl)-9H-fluorene; the terminal alkenyl polyphenylene ether has a structure shown in any one of Formulas 2 - 5;

[0087]

[0088] The 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene is the asymmetric divinylbenzyl fluorene described in the above technical solution or the asymmetric divinylbenzyl fluorene prepared by the preparation method described in the above technical solution.

[0089] As a specific embodiment of the present invention, the thermosetting hydrocarbon resin prepared using 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene as a raw material for preparation has a low dielectric constant (Dk(10GH) 2.8), a low dielectric loss tangent (Df(10GH) 0.00030), and a high glass transition temperature (Tg 360 °C).

[0090] As a specific embodiment of the present invention, in the raw materials for preparing the thermosetting hydrocarbon resin prepared using 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and 9,9'-bis(4-vinylbenzyl)-9H-fluorene as raw materials for preparation, the molar percentage of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVF) in 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVF) and 9,9'-bis(4-vinylbenzyl)-9H-fluorene (p,p-BVBF) can be 10-60%, and can also be 25-50%. In the present invention, the 9,9'-bis(4-vinylbenzyl)-9H-fluorene is a symmetric divinylbenzyl fluorene, and the symmetry means that there are the same substituents at the 9-position of the fluorene group. The structural formula of the 9,9'-bis(4-vinylbenzyl)-9H-fluorene is

[0091] As a specific embodiment of the present invention, the thermosetting hydrocarbon resin prepared using 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and 9,9'-bis(4-vinylbenzyl)-9H-fluorene as raw materials for preparation has properties of a very low dielectric constant, a very low dielectric loss tangent, and a quite high glass transition temperature. For example, when the molar ratio of o,p-BVF and p,p-BVBF is 1:1, the dielectric constant of the obtained thermosetting hydrocarbon resin is Dk(10GH) 2.8, the dielectric loss tangent is Df(10GH) 0.00042, and the glass transition temperature is 352 °C.

[0092] As a specific embodiment of the present invention, the number average molecular weight (Mn) of the terminal alkenyl polyphenylene ether in the raw materials for preparing the thermosetting crosslinked resin prepared using a crosslinking agent and a terminal alkenyl polyphenylene ether as raw materials for preparation can be 1800-2300. The terminal alkenyl polyphenylene ether can specifically be a terminal vinylbenzyl modified polyphenylene ether, and the structural formula of the terminal vinylbenzyl modified polyphenylene ether is;

[0093]

[0094] As a specific embodiment of the present invention, the preparation method of the terminal vinylbenzyl modified polyphenylene ether may include the following steps:

[0095] Perform oxidative coupling copolymerization on 2,6-dimethylphenol, diphenol and a catalyst under an oxygen condition to obtain hydroxylated polyphenylene ether;

[0096] React the hydroxylated polyphenylene ether with vinylbenzyl chloride under a phase transfer condition and precipitate with methanol to obtain the terminal vinylbenzyl modified polyphenylene ether.

[0097] As a specific embodiment of the present invention, the catalyst includes a copper amine complex catalyst; the copper amine complex catalyst includes N,N'-tetra-tert-butylethylenediamine, N-methylbutylamine, cuprous bromide, cuprous chloride, copper chloride or copper bromide; the number average molecular weight of the hydroxylated polyphenylene ether can be 1600 - 2000.

[0098] As a specific embodiment of the present invention, when using 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and 9,9'-bis(4-vinylbenzyl)-9H-fluorene as crosslinking agents to prepare the raw materials for the preparation of a thermosetting crosslinked resin, the mass percentage of the crosslinking agent can be 10 - 50%, and can also be 20 - 40%; the molar percentage of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVF) in the crosslinking agent can be 10 - 60%, and can also be 25 - 50%.

[0099] The thermosetting resin provided by the present invention has a low dielectric constant, a low dielectric loss tangent and an increased glass transition temperature, and has good application prospects as a resin material for high-frequency substrates.

[0100] The present invention also provides a preparation method of the thermosetting resin according to the above technical solution, including the following steps:

[0101] Dissolve the preparation raw materials and an initiator in toluene to obtain a mixed solution;

[0102] Remove toluene from the mixed solution and then perform melt thermal curing to obtain the thermosetting resin.

[0103] As a specific embodiment of the present invention, the initiator may include peroxides, and the peroxides may include di-tert-butyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, tert-butyl benzoyl peroxide, di(tert-butylperoxy) isopropylbenzene, benzoyl peroxide, di(4-methylbenzoyl) peroxide, dilauroyl peroxide, 1,1-bis(tert-butylperoxy) cyclohexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-bis(tert-butylperoxy) hexane, 3,3,5,7,7-pentamethyl-1,2,4-trioxane (T311), tert-butyl 2-ethylhexyl peroxide, tert-butyl peroxy-2-ethylhexyl carbonate; the mass ratio of the preparation raw materials to the initiator may be 1:0.001 to 0.008, or may also be 1:0.003 to 0.005.

[0104] As a specific embodiment of the present invention, the method for removing toluene from the mixed solution may be vacuum distillation.

[0105] As a specific embodiment of the present invention, the temperature of the melt thermal curing may be 200 to 240 °C, or may also be 210 to 230 °C; the pressure of the melt thermal curing may be 70 to 80 mmHg, or may also be 75 to 78 mmHg; the time of the melt thermal curing may be 80 to 120 min, or may also be 90 to 110 min.

[0106] The present invention also provides an application of the thermosetting resin described in the above technical solution or the thermosetting resin prepared by the preparation method described in the above technical solution as a resin material for a high-frequency and high-speed substrate.

[0107] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to examples, but they cannot be construed as limiting the protection scope of the present invention.

[0108] The analytical instruments and analytical test methods used in the examples are as follows:

[0109] 1. Purity determination method (HPLC): Agillent1260 high-pressure liquid chromatograph in the United States; column type: Kromasil100-5 C18 250 cm × 4.6 mm; mobile phase: acetonitrile / methanol volume ratio = 9:1; flow rate: 0.8 mL / min; detection wavelength: 254 nm; injection volume: 2 μL; pump mode: binary high-pressure gradient.

[0110] 2. Thermal analysis method: Pyris1 thermal analyzer (PerkinElemer company) is used to measure DSC, the heating range is 50 to 200 °C, and the heating rate is 10 °C / min.

[0111] 3. NMR spectrum determination: Bruker AV 400 nuclear magnetic resonance spectrometer, DMSO-d 6 as the solvent and TMS as the internal standard.

[0112] 4. Single crystal structure determination: Bruker D8 Venture single crystal diffractometer, General Rules for Molecular Structure Analysis Method JY / T 0588-2020.

[0113] 5. Determination of dielectric constant Dk(10 GHz) and dielectric loss tangent Df(10 GHz): By the molten sample casting method (thermal curing conditions: temperature 220 °C, pressure 70 - 80 mmHg, time 100 min). Resin thin films of 80 mm × 80 mm × 0.4 mm were prepared respectively and measured with an Agilent N5230A vector network analyzer in the United States at a frequency of 10 GHz (SPDR).

[0114] 6. Determination of polymer molecular weight: Agillent 1260 gel permeation chromatograph in the United States, tetrahydrofuran as the mobile phase and polystyrene as the standard.

[0115] 7. Determination of polymer glass transition temperature: Measured with a Perkin Elemer Differential Scanning Calorimeter dsc 4000 instrument.

[0116] 2-Vinylbenzyl chloride (HPLC purity 99.0%), 4-vinylbenzyl chloride (HPLC purity 99.5%), 1,2-bis(4-vinylphenyl)ethane (BVPE) (HPLC purity 99.5%) in the examples were all produced by Shandong Xingshun New Materials Co., Ltd.

[0117] 9-(2-Vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) was prepared in Examples 1 - 7, and thermosetting resins were prepared in Examples 8 - 13.

[0118] Example 1

[0119] Add 300 mL of anhydrous dimethyl sulfoxide, 1.10 mol of potassium tert-butoxide, and 0.3 g of inhibitor 701 into a reaction flask. Stir for 30 min under a nitrogen stream, then add 0.5 mol of fluorene. After stirring until dissolved, add 0.4 mol of 2-(chloromethyl)styrene dropwise. React under stirring conditions at 30 - 35 °C and 350 r / min for 1.0 h. Then, add 0.6 mol of 4-(chloromethyl)styrene dropwise under stirring conditions and continue stirring and reacting for 2.5 h. Slowly add the reaction solution to 1000 mL of ice water, filter the precipitated solid, wash it with water until the filtrate is neutral, and slurry the solid twice with 500 mL of methanol (at 30 °C). Filter the obtained solid and recrystallize it twice with toluene. Vacuum dry the obtained solid at 80 °C until a constant weight is achieved to obtain 144.5 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), with a yield of 72.5%.

[0120] o,p-BVBF is a white crystal. Perform high-performance liquid chromatography (HPLC) detection on the prepared o,p-BVBF to obtain an HPLC chromatogram, as Figure 2 shown. Table 1 shows the HPLC peak information; according to the HPLC detection results, the HPLC purity of o,p-BVBF is 99.15%.

[0121] Perform nuclear magnetic resonance (NMR) detection on the prepared o,p-BVBF to obtain 1 the \(^1\)H NMR spectrum and 13 the \(^{13}\)C NMR spectrum, as Figures 3 - 4 shown, where Figure 3 is the \(^1\)H NMR spectrum of o,p-BVBF, 1 and Figure 4 is the \(^{13}\)C NMR spectrum of o,p-BVBF. 13

[0122] 1 \(^1\)H NMR (400 MHz, DMSO-d 6 \(_6\)) δ: 3.43 (s, 2H, CH 2 \(_2\)), 3.54 (s, 2H, CH 2 \(_2\)), 5.03 - 5.08 (m, 2H, 2 × vinylic hydrogens), 5.40 - 5.59 (m, 2H, 2 × vinylic hydrogens), 6.40 - 6.42 (m, 1H, 1 × vinylic hydrogen), 6.49 (d, 2H, 2 × aromatic hydrogens), 6.70 - 6.77 (m, 2H, 2 × aromatic hydrogens), 6.97 - 7.01 (m, 3H, 2 × aromatic hydrogens, 1 × vinylic hydrogen), 6.87 - 6.95 (m, 1H, 1 × aromatic hydrogen), 7.05 - 7.20 (m, 4H, 4 × fluorene ring hydrogens), 7.22 - 7.25 (m, 1H, 1 × aromatic hydrogen), 7.33 - 7.58 (m, 4H, 4 × fluorene ring hydrogens).​​

[0123] 13 C NMR (100 MHz, DMSO-d 6 ): δ: 40.9 (CH 2 ), 43.3 (CH 2 ), 56.7 (9-fluorenyl C), 113.2, 115.0, 119.7, 124.7, 124.9, 125.3, 126.3, 126.5, 126.7, 127.1, 129.9, 130.9, 134.3, 134.9, 135.1, 136.3, 136.9, 137.0, 140.3, 148.0 (benzene ring C, fluorene ring C, vinyl C).

[0124] 1 The HNMR spectrum and 13 the C NMR spectrum are in complete agreement with the structure of o,p-BVBF.

[0125] The prepared o,p-BVBF was detected using a Pyris 1 thermal analyzer, and the DSC spectrum is as Figure 5 shown. It can be seen from Figure 5 that the melting point of o,p-BVBF is 171.4 - 172.7 °C.

[0126] Figure 6 is the single crystal structure diagram of o,p-BVBF, where ○ represents H atoms; Figure 7 is the crystal cell packing diagram of o,p-BVBF. The crystallographic parameters of o,p-BVBF are shown in Table 2, and the bond length and bond angle data of o,p-BVBF are shown in Table 3; the results of single crystal structure determination further confirm the molecular structure of o,p-BVBF.

[0127] Table 1 HPLC peak information of o,p-BVBF

[0128]

[0129]

[0130] Table 2 Crystallographic parameters of o,p-BVBF

[0131]

[0132] Table 3 Bond lengths and bond angles [°]

[0133]

[0134]

[0135] Example 2

[0136] Add 300 mL of anhydrous dimethyl sulfoxide, 1.10 mol of potassium tert-butoxide, and 0.3 g of inhibitor 701 into a reaction flask. After stirring for 30 min under a nitrogen stream, add 0.5 mol of fluorene. After stirring to dissolve, add dropwise 0.3 mol of 2-(chloromethyl)styrene; react under stirring at 35 °C and 350 r / min for 1.0 h; then add dropwise 0.7 mol of 4-(chloromethyl)styrene under stirring and continue stirring for reaction for 2.5 h; slowly add the reaction solution to 1000 mL of ice water, filter the precipitated solid, wash with water until the filtrate is neutral, and slurry the solid twice with 500 mL of methanol (30 °C); recrystallize the filtered solid twice with toluene, and vacuum dry the obtained solid at 80 °C until constant weight to obtain 110.8 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), white crystals, with a purity (HPLC) of 99.1% and a yield of 55.6%.

[0137] Example 3

[0138] Add 300 mL of anhydrous dimethyl sulfoxide, 1.10 mol of potassium tert-butoxide, and 0.3 g of inhibitor 701 into a reaction flask. After stirring for 30 min under a nitrogen stream, add 0.5 mol of fluorene. After stirring to dissolve, add dropwise 0.5 mol of 2-(chloromethyl)styrene; react under stirring at 35 °C and 350 r / min for 1.0 h; then add dropwise 0.5 mol of 4-(chloromethyl)styrene under stirring and continue stirring for reaction for 2.5 h; slowly add the reaction solution to 1000 mL of ice water, filter the precipitated solid, wash with water until the filtrate is neutral, and slurry the solid twice with 500 mL of methanol (30 °C); recrystallize the filtered solid twice with toluene, and vacuum dry the obtained solid at 80 °C until constant weight to obtain 126.7 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), white crystals, with a purity (HPLC) of 99.2% and a yield of 63.6%.

[0139] Example 4

[0140] Add 300 mL of anhydrous dimethyl sulfoxide, 1.10 mol of potassium tert-butoxide, and 0.3 g of inhibitor 701 into a reaction flask. After stirring for 30 min under a nitrogen stream, add 0.5 mol of fluorene. After stirring and dissolving, add dropwise a mixed solution of 0.4 mol of 2-(chloromethyl)styrene and 0.6 mol of 4-(chloromethyl)styrene. React under stirring at 35 °C and 350 r / min for 3.5 h. Then slowly add the reaction solution into 1000 mL of ice water. Filter the precipitated solid, wash it with water until the filtrate is neutral, and slurry the solid twice with 500 mL of methanol (30 °C). Recrystallize the filtered solid twice with toluene, and vacuum dry the obtained solid at 80 °C until a constant weight is achieved to obtain 90.6 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), a white crystal with a purity (HPLC) of 98.5% and a yield of 45.5%.

[0141] Example 5

[0142] Add 500 mL of toluene and 0.5 mol of fluorene into a reaction flask, stir and dissolve. Add 180 g of pre-prepared 50% sodium hydroxide solution, 8.5 g of tetrabutylammonium bromide (TBAB), and 0.3 g of inhibitor 701 under stirring. At 40 °C, add dropwise 0.4 mol of 2-(chloromethyl)styrene under stirring in a nitrogen stream, and react under stirring at 350 r / min for 4.0 h. Then add dropwise 0.6 mol of 4-(chloromethyl)styrene under stirring and continue to stir and react for 10 h. Cool to room temperature, slowly add 500 mL of water under stirring, separate the organic phase, wash it twice with 500 mL of water each time. Wash the organic phase with 500 mL of saturated ammonium chloride aqueous solution, and then wash it until neutral. Separate the organic phase and distill off toluene under reduced pressure. Slurry the solid twice with 500 mL of methanol (30 °C). Recrystallize the filtered solid twice with toluene, and vacuum dry the obtained solid at 80 °C until a constant weight is achieved to obtain 124.3 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), a white crystal with a purity (HPLC) of 98.5% and a yield of 62.4%.

[0143] Example 6

[0144] Add 500 mL of toluene, 0.5 mol of fluorene into a reaction flask, stir to dissolve; add 180 g of pre-prepared 50% sodium hydroxide solution, 8.5 g of tetrabutylammonium bromide (TBAB), and 0.3 g of inhibitor 701 under stirring; at 40 °C, dropwise add a mixed solution of 0.5 mol of 2-(chloromethyl)styrene and 0.5 mol of 4-(chloromethyl)styrene under stirring in a nitrogen stream; react for 14.0 h under stirring at 350 r / min; cool to room temperature, slowly add 500 mL of water under stirring, separate the organic phase, wash twice with water, 500 mL of water each time; wash the organic phase with 500 mL of saturated ammonium chloride aqueous solution, and wash with water until neutral; separate the organic phase, distill off toluene under reduced pressure; slurry the solid with 500 mL of methanol (30 °C) twice; recrystallize the obtained solid from toluene twice, vacuum dry the obtained solid at 80 °C until constant weight, to obtain 84.7 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), white crystals, purity (HPLC) 98.5%, and the yield is 42.5%.

[0145] Example 7

[0146] Add 500 mL of acetonitrile, 1.2 mol of potassium hydroxide powder, 30 g of PEG-400, 0.3 g of inhibitor 701 into a reaction flask, add 0.5 mol (83 g) of fluorene under stirring; at 40 °C, dropwise add 0.4 mol of 2-(chloromethyl)styrene under stirring in a nitrogen stream, react for 4.0 h under stirring at 350 r / min; then dropwise add 0.6 mol of 4-(chloromethyl)styrene under stirring, continue to stir and react for 8.0 h; stop the reaction, distill off acetonitrile, then add 500 mL of water and 500 mL of toluene, separate the layers, wash the organic phase with 500 mL of saturated ammonium chloride solution, wash with water until neutral, distill off toluene under reduced pressure, slurry the solid with 500 mL of methanol (30 °C) twice; recrystallize the obtained solid from toluene twice, vacuum dry the obtained solid at 80 °C until constant weight, to obtain 106.6 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), white crystals, purity (HPLC) 98.7%, and the yield is 53.5%.

[0147] Example 8

[0148] Dissolve 20 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) prepared in Example 1 and 0.1 g of T311 peroxide initiator in 50 g of toluene; remove the solvent under reduced pressure, and then prepare a thermosetting hydrocarbon resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70 - 80 mmHg, time is 100 min); measure the glass transition temperature; make the prepared resin into an 80 mm × 80 mm × 0.4 mm thin sheet, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz using an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0149] Example 9

[0150] Add 500 mL of acetonitrile, 1.4 mol of potassium tert-butoxide, 30 g of PEG-400, and 0.5 g of inhibitor 701 to a reaction flask. Under a nitrogen stream and stirring conditions, add 0.6 mol of fluorene and 1.4 mol of 4-vinylbenzyl chloride (HPLC, 99%); react under stirring conditions at 30 - 35 °C and 350 r / min until the fluorene content analyzed by HPLC < 1 wt%; stop the reaction, distill off the acetonitrile, then add 500 mL of water and 500 mL of toluene, separate the layers, wash the organic phase with saturated ammonium chloride solution, and wash with water 3 times (500 mL of water each time) until neutral. Distill off toluene under reduced pressure, add a mixed solvent of toluene and methanol with a volume ratio of 1:0.3, heat until completely dissolved, cool to 5 °C at a rate of 0.5 °C / min and keep it at a constant temperature for crystallization, filter, and dry the obtained solid component at 90 °C until constant weight to obtain 9,9-bis(2-vinylbenzyl)-9H-fluorene (p,p-BVBF), a white crystal, with a melting point of 118.5 - 120.0 °C and a purity (HPLC) of 99.5%.

[0151] Dissolve 20 g of 9,9-bis(4-vinylbenzyl)-9H-fluorene (p,p-BVBF) and 0.1 g of T311 peroxide initiator in 50 g of toluene; remove the solvent under reduced pressure, and then prepare a thermosetting hydrocarbon resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70 - 80 mmHg, time is 100 min); measure the glass transition temperature; make the prepared resin into an 80 mm × 80 mm × 0.4 mm thin sheet, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz using an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0152] Example 10

[0153] 9,9-Bis(2-vinylbenzyl)-9H-fluorene (p,p-BVBF) was prepared according to the method of Example 9. It was a white crystal with a melting point of 118.5 - 120.0 °C and a purity (HPLC) of 99.5%.

[0154] 10 g of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) and 10 g of 9,9-bis(4-vinylbenzyl)-9H-fluorene (p,p-BVBF) prepared in Example 1, along with 0.1 g of T311 peroxide initiator, were dissolved in 50 g of toluene. The solvent was removed under reduced pressure, and then a thermosetting hydrocarbon resin was prepared by the melt casting method (thermal curing conditions: temperature 220 °C, pressure 70 - 80 mmHg, time 100 min). The glass transition temperature was measured. The prepared resin was made into a 80 mm × 80 mm × 0.4 mm thin sheet, and the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz were measured using an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0155] Example 11

[0156] 150 mL of methanol, 0.09 mol of N,N-di-tert-butylethylenediamine, and 0.07 mol of copper bromide were added to a 2 L four-necked flask and stirred until dissolved. Then, oxygen was continuously bubbled in, and the mixture was stirred and reacted at a controlled temperature of 40 - 45 °C. A 500 mL toluene / 150 mL methanol mixed solution containing 1.0 mol of 2,6-dimethylphenol and 0.125 mol of tetramethylbisphenol A was added dropwise to the reaction flask. After the addition was completed, oxygen bubbling was continued, and the mixture was stirred and reacted at the same temperature for 4 h. After the reaction was completed, it was neutralized to neutral with 10% dilute hydrochloric acid. 50 mL of an aqueous solution containing 7 g (0.04 mol) of EDTA-2Na was added, and the mixture was stirred for 30 min. 600 mL of methanol was added, and the precipitate was filtered out and washed three times by slurrying with 300 mL of methanol. It was dried in vacuo at 80 °C for 8 h to obtain 285.0 g of polyphenylene ether (XSPPO); Mn = 1750, Mw = 2030.

[0157] Add 120 mL of toluene into a 500 mL four-necked flask, add 60 g of polyphenylene ether (SXPPO), 60 mL of 50% sodium hydroxide solution, 4 g (0.043 mol) of tetrabutylammonium bromide, 0.1 g of inhibitor 701, and 15 g (0.18 mol) of p-chloromethylstyrene. Stir and heat up to 70 °C under nitrogen protection; stir and react for 8 h; cool to room temperature, neutralize with 10% dilute hydrochloric acid to neutral; wash the organic phase three times with 200 mL of water; add it to 800 mL of methanol, filter the precipitated solid, wash it with methanol / water (weight ratio 80:20), and dry it in vacuum at 80 °C for 8 h to obtain 82 g of modified polyphenylene ether (XSmPPO), Mn = 1860, Mw = 2180; the structural formula of XSmPPO is:

[0158]

[0159] Dissolve 4 g (0.01 mol) of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) prepared in Example 1, 16 g of XSmPPO, and 0.1 g of T311 peroxide initiator in 50 g of toluene; remove the solvent under reduced pressure, and then prepare the cross-linked resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70 - 80 mmHg, time is 100 min); measure the glass transition temperature; make the cross-linked resin into a thin sheet of 80 mm × 80 mm × 0.4 mm, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz with an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0160] Example 12

[0161] Prepare 9,9-bis(4-vinylbenzyl)-9H-fluorene (p,p-BVBF) according to the method of Example 9;

[0162] Prepare modified polyphenylene ether (XSmPPO) according to the method of Example 11;

[0163] Dissolve 4 g (0.01 mol) of p,p-BVBF, 16 g of XSmPPO, and 0.1 g of T311 peroxide initiator in 50 g of toluene; remove the solvent under reduced pressure, and then prepare the cross-linked resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70 - 80 mmHg, time is 100 min); measure the glass transition temperature; make the cross-linked resin into a thin sheet of 80 mm × 80 mm × 0.4 mm, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz with an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0164] Example 13

[0165] Prepare 9,9-bis(4-vinylbenzyl)-9H-fluorene (p,p-BVBF) according to the method of Example 9;

[0166] Prepare modified polyphenylene ether (XSmPPO) according to the method of Example 11;

[0167] Dissolve 2 g (0.005 mol) of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF), 2 g (0.005 mol) of p,p-BVBF, 16 g of XSmPPO and 0.1 g of T311 peroxide initiator prepared in Example 1 in 50 g of toluene; remove the solvent under reduced pressure, and then prepare a cross-linked resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70-80 mmHg, time is 100 min); measure the glass transition temperature; make the cross-linked resin into an 80 mm×80 mm×0.4 mm thin sheet, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz with an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0168] Comparative Example 1

[0169] Dissolve 20 g of 1,2-bis(4-vinylphenyl)ethane (BVPE) and 0.1 g of T311 peroxide initiator in 50 g of toluene; remove the solvent under reduced pressure, and then prepare a thermosetting hydrocarbon resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70-80 mmHg, time is 100 min); measure the glass transition temperature; make the resin into an 80 mm×80 mm×0.4 mm resin thin sheet, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz with an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0170] Comparative Example 2

[0171] Prepare modified polyphenylene ether (XSmPPO) according to the method of Example 11;

[0172] Dissolve 20 g of modified polyphenylene ether (XSmPPO) and 0.1 g of T311 peroxide initiator in 50 g of toluene, and remove the solvent under reduced pressure; then prepare a thermosetting resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70-80 mmHg, time is 100 min); measure the glass transition temperature; make the resin into an 80 mm×80 mm×0.4 mm thin sheet, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz with an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0173] Comparative Example 3

[0174] Prepare modified polyphenylene ether (XSmPPO) according to the method of Example 11;

[0175] Dissolve 2.34 g (0.01 mol) of 1,2-bis(4-vinylphenyl)ethane (BVPE), 17.66 g of modified polyphenylene ether (XSmPPO), and 0.1 g of T311 peroxide initiator in 50 g of toluene, and remove the solvent under reduced pressure; then prepare a crosslinked resin by the melt casting method (thermal curing conditions: temperature is 220 °C, pressure is 70 - 80 mmHg, time is 100 min); measure the glass transition temperature; make the crosslinked resin into a 80 mm × 80 mm × 0.4 mm thin sheet, and measure the dielectric constant and dielectric loss tangent of the sample at a frequency of 10 GHz with an Agilent N5230A vector network analyzer in the United States. The results are listed in Table 4.

[0176] Table 4 Performance parameters of the thermosetting resins prepared in Examples 8 - 13 and Comparative Examples 1 - 3

[0177]

[0178]

[0179] In Table 4, Dk is the dielectric constant, Df is the dielectric loss tangent, and Tg is the glass transition temperature.

[0180] It can be seen from Table 4 that the thermosetting hydrocarbon resin prepared from 9,9-bis(4-vinylbenzyl)-9H-fluorene has a very low dielectric loss tangent and a relatively high glass transition temperature (Examples 8, 9, 10). Among them, the thermosetting hydrocarbon resin prepared from 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) has the lowest dielectric loss tangent and the highest glass transition temperature (Example 8). The crosslinked resin of 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene (o,p-BVBF) (Example 11), 9,9-bis(4-vinylbenzyl)-9H-fluorene (p,p-BVBF) (Example 12), or a 1:1 mixture of the two (Example 13) with the end-vinyl modified polyphenylene ether, compared with the crosslinked resin of the common crosslinking agent 1,2-bis(4-vinylphenyl)ethane (BVPE) and the end-vinyl modified polyphenylene ether (Comparative Example 3), has a significantly reduced dielectric constant, a greatly reduced dielectric loss tangent, and a significantly increased glass transition temperature. And the higher the weight ratio of o,p-BVBF used as the crosslinking agent, the lower the dielectric loss tangent and the higher the glass transition temperature. Therefore, the thermosetting hydrocarbon resin and the thermosetting crosslinked resin with modified polyphenylene ether of the present invention have excellent comprehensive properties and can be used as the resin material for high-frequency and high-speed printed circuit boards.

[0181] Although the above embodiments have described the present invention in detail, they are only some embodiments of the present invention, rather than all embodiments. People can also obtain other embodiments based on this embodiment without creative efforts, and these embodiments all fall within the protection scope of the present invention.

Claims

1. An asymmetric divinylbenzylfluorene, characterized in that: 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene having the structure shown in Formula 1: The 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene has a melting endothermic peak of 169-175° C. in thermal analysis, has a monoclinic crystal system, and a space group of P21 / c.

2. The method for preparing asymmetric divinylbenzylfluorene according to claim 1, characterized in that: The following steps are involved: Mixing fluorene, an alkaline agent, a polymerization inhibitor and a polar aprotic solvent to obtain a fluorene-containing mixed system; 2-vinylbenzyl chloride and 4-vinylbenzyl chloride are sequentially added dropwise to the fluorene-containing mixed system, or a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride is added dropwise to the fluorene-containing mixed system to carry out a nucleophilic substitution reaction to obtain the asymmetric divinylbenzylfluorene.

3. The method for preparing asymmetric divinylbenzylfluorene according to claim 2, characterized in that: The alkaline agent includes one or more of alkali metal hydroxide, alkali metal alkoxide, sodium hydride and potassium hydride; The polymerization inhibitor includes one or more of nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butyl-catechol, 2,2,6,6-tetramethylpiperidine nitroxide and 2,2,6,6-tetramethyl-4-hydroxypiperidine nitroxide; The polar aprotic solvent includes dimethyl sulfoxide, sulfolane, N,N-dimethylformamide, N,N-diethylformamide, acetonitrile or hexamethylphosphoramide; The molar ratio of fluorene to the alkaline agent is 1:1.8-5; The molar ratio of 2-vinylbenzyl chloride to 4-vinylbenzyl chloride is 2-6:4-8; The molar ratio of the total molar amount of the 2-vinylbenzyl chloride and the 4-vinylbenzyl chloride to fluorene is 1.8 to 2.2:

1.

4. The method for preparing asymmetric divinylbenzylfluorene according to claim 2 or 3, characterized in that: The temperature of the nucleophilic substitution reaction is 20-50° C. and the time is 2-8 hours.

5. The method for preparing asymmetric divinylbenzylfluorene according to claim 1, characterized in that: The following steps are involved: Mixing fluorene, an alkaline agent, a polymerization inhibitor, a phase transfer catalyst and a solvent to obtain a fluorene-containing phase transfer catalyst system; 2-vinylbenzyl chloride and 4-vinylbenzyl chloride are sequentially added dropwise to the fluorene-containing phase transfer catalyst system, or a mixed solution of 2-vinylbenzyl chloride and 4-vinylbenzyl chloride is added dropwise to the fluorene-containing phase transfer catalyst system, and a nucleophilic substitution reaction is carried out under phase transfer catalysis conditions to obtain the asymmetric divinylbenzylfluorene.

6. The method for preparing asymmetric divinylbenzylfluorene according to claim 5, characterized in that: The alkaline agent includes alkali metal hydroxide and / or alkali metal alkoxide; The polymerization inhibitor includes one or more of nitromethane, nitrobenzene, o-nitrophenol, phenothiazine, 2-phenylnaphthylamine, hydroquinone, catechol, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, p-tert-butyl-catechol, 2,2,6,6-tetramethylpiperidine nitroxide and 2,2,6,6-tetramethyl-4-hydroxypiperidine nitroxide; The phase transfer catalyst includes one or more of quaternary ammonium salt, quaternary phosphonium salt and polyethylene glycol; The mass of the phase transfer catalyst is 5 to 25% of the mass of fluorene; The molar ratio of fluorene to the alkaline agent is 1:1.8-5; The molar ratio of 2-vinylbenzyl chloride to 4-vinylbenzyl chloride is 2-6:4-8; The molar ratio of the total molar amount of the 2-vinylbenzyl chloride and the 4-vinylbenzyl chloride to fluorene is 1.8 to 2.2:

1.

7. The method for preparing asymmetric divinylbenzylfluorene according to claim 5 or 6, characterized in that: The temperature of the nucleophilic substitution reaction under the phase transfer catalysis condition is 25-75° C. and the time is 8-18 hours.

8. Thermosetting resin, characterized in that The invention comprises a thermosetting hydrocarbon resin and / or a thermosetting cross-linking resin, wherein the thermosetting hydrocarbon resin comprises a thermosetting hydrocarbon resin prepared by using 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene as a raw material and / or a thermosetting hydrocarbon resin prepared by using 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and 9,9'-bis(4-vinylbenzyl)-9H-fluorene as raw materials; The thermosetting cross-linked resin includes a thermosetting cross-linked resin prepared using a cross-linking agent and terminal alkenyl polyphenylene ether as raw materials; the cross-linking agent includes 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene and / or 9,9'-bis(4-vinylbenzyl)-9H-fluorene; the terminal alkenyl polyphenylene ether has a structure shown in any one of Formulas 2 to 5; The 9-(2-vinylbenzyl)-9'-(4-vinylbenzyl)-9H-fluorene is the asymmetric divinylbenzylfluorene according to claim 1 or the asymmetric divinylbenzylfluorene prepared by the preparation method according to any one of claims 2 to 7.

9. The method for preparing the thermosetting resin according to claim 8, characterized in that: The following steps are involved: Dissolving the preparation raw materials and the initiator in toluene to obtain a mixed solution; The toluene in the mixed solution is removed and then melt-cured to obtain the thermosetting resin.

10. Use of the thermosetting resin according to claim 8 or the thermosetting resin prepared by the preparation method according to claim 9 as a resin material for high-frequency and high-speed substrates.

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