Halogen-free high-frequency copper clad plate and manufacturing method thereof

Abstract

The application discloses a kind of halogen-free high-frequency copper-clad plate and its manufacturing method, belong to copper-clad plate preparation technical field, manufacturing method is as follows: fluorine-containing mercaptan grafting polybutadiene, styrene-butadiene-styrene copolymer, dicyclopentadiene phenol epoxy resin, toluene, butanone, propylene glycol monomethyl ether are added into mixing machine, after stirring and mixing, initiator, active ester curing agent, diamond-based flame-retardant filler are added, stirring and mixing 2-4h, obtain resin glue liquid;Glass cloth is placed in resin glue liquid and immersed after taking out, baking, obtain prepreg;Prepreg is laminated, the copper-clad plate obtained by the application has lower dielectric constant, better flame-retardant property, higher heat dissipation performance, lower water absorption and good mechanical processing, etc.Advantages, in the field of communication, vehicle-mounted millimeter wave radar, internet of things, automobile electronics and other fields of high multilayer high-frequency circuit board have broad application prospect.

Description

Technical Field

[0001] This invention belongs to the field of copper clad laminate preparation technology, specifically relating to a halogen-free high-frequency copper clad laminate and its manufacturing method. Background Technology

[0002] Copper clad laminate (CCL), also known as circuit board, is a type of board material formed by covering one or both sides of copper foil with reinforcing materials, resin, fillers, curing agents, and other raw materials through a specific process and then hot-pressing them together. With the advancement of electronic technology, modern communication equipment has developed towards high integration and high frequency 5G. CCL, as a fundamental material for electronic devices, plays a crucial role and has attracted widespread attention. For use at high frequencies, CCL requires low dielectric constant and low dielectric loss. The miniaturization and high-density integration of electronic devices at high frequencies lead to increased heat generation, resulting in higher requirements for the flame retardant and heat dissipation properties of CCL. Furthermore, with increasing environmental awareness, halogen-free flame-retardant products are becoming more popular. Therefore, research on low dielectric constant, high thermal conductivity halogen-free high-frequency CCL suitable for high-frequency applications is currently a key focus.

[0003] The low polarity of CH in hydrocarbon resin molecules and the zigzag arrangement of molecular chains give it excellent dielectric properties, making it one of the ideal matrix resins for high-frequency copper-clad laminates. However, its flame retardancy and thermal conductivity need to be improved, which limits the application of copper-clad laminates made from it in the high-frequency field. Summary of the Invention

[0004] The purpose of this invention is to provide a halogen-free high-frequency copper-clad laminate and its manufacturing method, thereby solving the problems of poor flame retardancy and thermal conductivity of existing hydrocarbon resin-based copper-clad laminates.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A method for manufacturing a halogen-free high-frequency copper-clad laminate includes the following steps:

[0007] S1. Add fluorinated thiol-grafted polybutadiene, styrene-butadiene-styrene copolymer, dicyclopentadiene phenol epoxy resin, toluene, methyl ethyl ketone, and propylene glycol monomethyl ether to a mixer and stir for 30-60 minutes. Then add initiator, active ester curing agent, and diamond-based flame retardant filler and stir for 2-4 hours at a speed of 1500-2000 r / min to obtain resin solution.

[0008] S2. Immerse the glass in the resin solution prepared in S1 for 30-36 minutes, then remove it and bake it in an oven at 150-160℃ for 5 minutes, then cool it to room temperature to obtain a semi-cured sheet.

[0009] S3. Cut the prepreg obtained in S2 into the same size, in groups of 2-8, and then stack them with copper foil. Hot press them for 260 minutes at a pressure of 1.8-2.5MPa and a temperature of 250-260℃ to obtain a halogen-free high-frequency copper-clad laminate.

[0010] Furthermore, the mass ratio of fluorinated thiol-grafted polybutadiene, styrene-butadiene-styrene copolymer, initiator, dicyclopentadiene phenol epoxy resin, reactive ester curing agent, diamond-based flame retardant filler, toluene, methyl ethyl ketone, and propylene glycol monomethyl ether in S1 is 100:50:6:30:5:50-60:80:20:10.

[0011] The diamond-based flame-retardant filler is a hyperbranched polyamide grafted with nanodiamonds. The hyperbranched polyamide is obtained by reacting tris(3-aminophenyl)phosphorus oxide and bi-terminated carboxylsiloxane.

[0012] Furthermore, the preparation process of diamond-based flame-retardant fillers is as follows:

[0013] Weigh out tris(3-aminophenyl)phosphine oxide and bi-terminated carboxylsiloxane and add them to a flask. Then add N-methylpyrrolidone, pyridine and triphenyl phosphite. Stir at room temperature for 5-10 min, then add carboxylated nanodiamonds. Disperse by ultrasonication for 30 min, stir at room temperature for 2 h, react at 70℃ for 2 h, and react at 130℃ for 8 h. After the reaction is completed, cool to room temperature, filter, wash the filter cake with acetone and dry to obtain diamond-based flame retardant filler.

[0014] The ratio of phosphorus tri(3-aminophenyl)oxide, bi-terminated carboxysiloxane, N-methylpyrrolidone, pyridine, triphenyl phosphite and carboxylated nanodiamond is 1.2g:1g:20-40mL:5mL:6mL:0.35-0.44g.

[0015] This invention uses tris(3-aminophenyl)phosphorus oxide and bi-terminated carboxylsiloxane as A3 and B2 type monomers, respectively. In the presence of carboxylated nanodiamonds, an in-situ polymerization reaction occurs, grafting phosphorus- and silicon-containing hyperbranched polyamide molecules onto the surface of nanodiamonds. This improves the dispersibility of nanodiamonds in the resin matrix while introducing active amino groups onto their surface, enhancing the compatibility and interfacial interaction between nanodiamonds and the matrix. While ensuring the composite material has low dielectric loss, it endows the composite material with excellent heat dissipation and flame retardant properties. The heat dissipation performance mainly depends on the excellent thermal conductivity of nanodiamonds. The flame retardant properties are reflected on the one hand by the synergistic flame retardant effect of N, P, and Si in the hyperbranched polyamide, and on the other hand by the physical barrier formed by the nanodiamond particles, which isolates flames and flammable gases and slows down the spread of flames.

[0016] Furthermore, the dicarboxylated siloxane is obtained by hydrosilylation reaction of acrylic acid and 1,1,3,3-tetramethyldisiloxane, as follows:

[0017] Weigh acrylic acid and add it to a flask. Heat the flask to 40°C. First, add isopropanol chloroplatinic acid solution dropwise, then add 1,1,3,3-tetramethyldisiloxane dropwise. After the addition is complete, raise the temperature to 70°C and stir the reaction for 2-3 hours. Remove isopropanol and unreacted acrylic acid by vacuum distillation to obtain the bi-terminated carboxylsiloxane.

[0018] The molar ratio of acrylic acid to 1,1,3,3-tetramethyldisiloxane is 2.1-2.3:1, the mass fraction of the isopropanol chloroplatinate solution is 1%, and the amount of isopropanol chloroplatinate solution used is 10-20 ppm of the total amount of 1,1,3,3-tetramethyldisiloxane and acrylic acid.

[0019] Furthermore, the preparation process of carboxylated nanodiamonds is as follows:

[0020] Weigh out nanodiamonds and spread them evenly on the bottom of a ceramic boat. Then transfer them to a muffle furnace and oxidize them at high temperature in an air atmosphere. Set the heating rate to 5℃ / min. After heating from room temperature to 425℃, hold the temperature for 1-3 hours and then cool to room temperature. Grind the resulting powder to obtain carboxylated diamond.

[0021] Furthermore, the preparation process of fluorinated thiol-grafted polybutadiene is as follows:

[0022] Polybutadiene was weighed and added to tetrahydrofuran. After dissolving by magnetic stirring, fluorinated thiols and photoinitiator 907 were added. The mixture was reacted for 2 hours under a nitrogen atmosphere and irradiated with 365 nm ultraviolet light. The product was then precipitated in anhydrous ethanol and dried in a vacuum oven at 40 °C for 24 hours to obtain fluorinated thiols-grafted polybutadiene. The mass ratio of polybutadiene, tetrahydrofuran, fluorinated thiols, and photoinitiator 907 was 5:100:0.5-1.5:0.005. The number average molecular weight of polybutadiene was 2000. Through the click reaction of double bonds and mercapto groups, sulfide structures and fluorocarbon long chains were introduced into the molecular chain of polybutadiene, giving the composite material good water resistance and further improving its flame retardant properties.

[0023] Furthermore, the fluorinated thiol is one or a mixture of 1H,1H,2H,2H-perfluorooctylthiol, 1H,1H,2H,2H-perfluorododecylthiol and pentafluoropentanethiol.

[0024] Furthermore, the number-average molecular weight of the styrene-butadiene-styrene copolymer is 7,000-30,000.

[0025] Furthermore, the active ester curing agent is HPC-8000-65T active ester resin, a product of DIC Corporation of Japan.

[0026] Furthermore, the initiator is composed of 2,3-dimethyl-2,3-diphenylbutane and di-tert-butylperoxyisopropylbenzene in a mass ratio of 1:1.

[0027] Furthermore, the glass cloth is type 2116 electronic-grade glass fiber cloth.

[0028] A halogen-free high-frequency copper-clad laminate is prepared by the above-described manufacturing method.

[0029] The beneficial effects of this invention are:

[0030] This invention uses fluorinated thiol-grafted polybutadiene and styrene-butadiene-styrene copolymer as the main resins, adds special epoxy resin to improve the peel resistance of copper-clad laminate, adds diamond-based flame-retardant filler to improve flame retardancy and heat dissipation performance, and then adds initiators, curing agents and solvents to prepare a resin solution. The resulting copper-clad laminate has advantages such as low dielectric constant, good flame retardancy, high heat dissipation performance, low water absorption rate and good machinability. It has broad application prospects in high-multilayer high-frequency circuit boards in the fields of communications, automotive millimeter-wave radar, Internet of Things, and automotive electronics. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1

[0033] This embodiment provides a diamond-based flame-retardant filler, the preparation process of which is as follows:

[0034] Weigh 1.2g of tris(3-aminophenyl)phosphine oxide and 1g of bi-terminated carboxylsiloxane into a flask, then add 20mL of N-methylpyrrolidone, 5mL of pyridine and 6mL of triphenyl phosphite. After stirring at room temperature for 5min, add 0.35g of carboxylated nanodiamonds, sonicate for 30min, stir and react at room temperature for 2h, react at 70℃ for 2h, react at 130℃ for 8h. After the reaction is completed, cool to room temperature, filter, wash the filter cake with acetone and dry to obtain diamond-based flame retardant filler.

[0035] The preparation process of double-terminated carboxylsiloxanes is as follows:

[0036] Weigh 2.1 mol of acrylic acid and add it to a flask. Heat the flask to 40°C. First, add 1 wt% isopropanol chloroplatinate solution dropwise, then add 1 mol of 1,1,3,3-tetramethyldisiloxane dropwise. After the addition is complete, raise the temperature to 70°C and stir the reaction for 2 hours. Remove isopropanol and unreacted acrylic acid by vacuum distillation to obtain the bi-terminated carboxylsiloxane. The amount of isopropanol chloroplatinate solution used is 10 ppm of the total amount of 1,1,3,3-tetramethyldisiloxane and acrylic acid.

[0037] The preparation process of carboxylated nanodiamonds is as follows:

[0038] Nanodiamonds (purchased from Guangzhou Guangda Electromechanical Co., Ltd.) were weighed and evenly spread on the bottom of a ceramic boat, then transferred to a muffle furnace and oxidized at high temperature in an air atmosphere. The heating rate was set to 5℃ / min. The temperature was raised from room temperature to 425℃ and held for 1 hour before being cooled to room temperature. The resulting powder was then ground to obtain carboxylated diamonds.

[0039] Example 2

[0040] This embodiment provides a diamond-based flame-retardant filler, the preparation process of which is as follows:

[0041] Weigh 1.2g of tris(3-aminophenyl)phosphine oxide and 1g of bi-terminated carboxylsiloxane into a flask, then add 40mL of N-methylpyrrolidone, 5mL of pyridine and 6mL of triphenyl phosphite. After stirring at room temperature for 10min, add 0.44g of carboxylated nanodiamonds, sonicate for 30min, stir and react at room temperature for 2h, react at 70℃ for 2h, react at 130℃ for 8h. After the reaction is completed, cool to room temperature, filter, wash the filter cake with acetone and dry to obtain diamond-based flame retardant filler.

[0042] The preparation process of double-terminated carboxylsiloxanes is as follows:

[0043] Weigh 2.3 mol of acrylic acid and add it to a flask. Heat the flask to 40°C. First, add 1 wt% isopropanol chloroplatinate solution dropwise, then add 1 mol of 1,1,3,3-tetramethyldisiloxane dropwise. After the addition is complete, raise the temperature to 70°C and stir the reaction for 3 hours. Remove isopropanol and unreacted acrylic acid by vacuum distillation to obtain the bi-terminated carboxylsiloxane. The amount of isopropanol chloroplatinate solution used is 20 ppm of the total amount of 1,1,3,3-tetramethyldisiloxane and acrylic acid.

[0044] The preparation process of carboxylated nanodiamonds is the same as in Example 1.

[0045] Comparative Example 1

[0046] This embodiment provides a diamond-based flame-retardant filler, the preparation process of which is as follows:

[0047] Weigh 1.2g of tris(3-aminophenyl)phosphine oxide and 0.55g of adipic acid and add them to a flask. Then add 40mL of N-methylpyrrolidone, 5mL of pyridine and 6mL of triphenyl phosphite. Stir at room temperature for 5min, then add 0.35g of carboxylated nanodiamonds. Disperse by ultrasonication for 30min, stir at room temperature for 2h, react at 70℃ for 2h, and react at 130℃ for 8h. After the reaction is completed, cool to room temperature, filter, wash the filter cake with acetone and dry to obtain diamond-based flame retardant filler. The preparation process of carboxylated nanodiamonds is the same as in Example 1.

[0048] Example 3

[0049] A method for manufacturing a halogen-free high-frequency copper-clad laminate includes the following steps:

[0050] S1. Add 100g of fluorinated thiol-grafted polybutadiene, 50g of styrene-butadiene-styrene copolymer, 30g of dicyclopentadiene phenol epoxy resin, 80g of toluene, 20g of butanone, and 10g of propylene glycol monomethyl ether to a mixer and stir for 30min. Then add 6g of initiator, 5g of active ester curing agent, and 50g of diamond-based flame retardant filler from Example 1 and stir for 2h at 1500r / min to obtain resin solution.

[0051] S2. The 2116 type electronic grade glass fiber is immersed in the resin solution prepared in S1 for 30 minutes, then removed and baked in an oven at 150°C for 5 minutes, and then cooled to room temperature to obtain a semi-cured sheet.

[0052] S3. Cut the prepreg obtained in S2 into the same size, two sheets per group, and then stack them with copper foil. Hot press them at a pressure of 1.8MPa and a temperature of 260℃ for 260 minutes to obtain a halogen-free high-frequency copper-clad laminate.

[0053] The preparation process of fluorinated thiol-grafted polybutadiene is as follows:

[0054] 5g of polybutadiene (number average molecular weight of 2000) was weighed and added to 100g of tetrahydrofuran. After dissolving by magnetic stirring, 0.5g of 1H,1H,2H,2H-perfluorooctyl mercaptan and 0.005g of photoinitiator 907 were added. The mixture was reacted for 2h under a nitrogen atmosphere and irradiated with 365nm ultraviolet light. After precipitation in anhydrous ethanol, the product was dried in a vacuum oven at 40℃ for 24h to obtain fluorinated mercaptan-grafted polybutadiene.

[0055] The styrene-butadiene-styrene copolymer has a number-average molecular weight of 7000, the active ester curing agent is HPC-8000-65T active ester resin from DIC Corporation of Japan, and the initiator is composed of 2,3-dimethyl-2,3-diphenylbutane and di-tert-butylperoxyisopropylbenzene in a mass ratio of 1:1.

[0056] Example 4

[0057] A method for manufacturing a halogen-free high-frequency copper-clad laminate includes the following steps:

[0058] S1. Add 100g of fluorinated thiol-grafted polybutadiene, 50g of styrene-butadiene-styrene copolymer, 30g of dicyclopentadiene phenol epoxy resin, 80g of toluene, 20g of butanone, and 10g of propylene glycol monomethyl ether to a mixer and stir for 40min. Then add 6g of initiator, 5g of active ester curing agent, and 55g of diamond-based flame retardant filler from Example 2. Stir and mix at 1800r / min for 3h to obtain resin solution.

[0059] S2. The 2116 type electronic grade glass fiber is immersed in the resin solution prepared in S1 for 33 minutes, then removed and baked in an oven at 155℃ for 5 minutes and then cooled to room temperature to obtain a semi-cured sheet.

[0060] S3. Cut the prepreg obtained in S2 into the same size, two sheets per group, and then stack them with copper foil. Hot press them at a pressure of 2.2 MPa and a temperature of 255℃ for 260 min to obtain a halogen-free high-frequency copper-clad laminate.

[0061] The preparation process of fluorinated thiol-grafted polybutadiene is as follows:

[0062] 5g of polybutadiene (number average molecular weight of 2000) was weighed and added to 100g of tetrahydrofuran. After dissolving by magnetic stirring, 1.0g of 1H,1H,2H,2H-perfluorododecanethiol and 0.005g of photoinitiator 907 were added. The mixture was reacted for 2h under a nitrogen atmosphere and irradiated with 365nm ultraviolet light. The product was then precipitated in anhydrous ethanol and dried in a vacuum oven at 40℃ for 24h to obtain fluorinated thiol-grafted polybutadiene.

[0063] The styrene-butadiene-styrene copolymer has a number-average molecular weight of 1000, the active ester curing agent is HPC-8000-65T active ester resin from DIC Corporation of Japan, and the initiator is composed of 2,3-dimethyl-2,3-diphenylbutane and di-tert-butylperoxyisopropylbenzene in a mass ratio of 1:1.

[0064] Example 5

[0065] A method for manufacturing a halogen-free high-frequency copper-clad laminate includes the following steps:

[0066] S1. Add 100g of fluorinated thiol-grafted polybutadiene, 50g of styrene-butadiene-styrene copolymer, 30g of dicyclopentadiene phenol epoxy resin, 80g of toluene, 20g of butanone, and 10g of propylene glycol monomethyl ether to a mixer and stir for 60min. Then add 6g of initiator, 5g of active ester curing agent, and 60g of diamond-based flame retardant filler from Example 2. Stir and mix at 2000r / min for 4h to obtain resin solution.

[0067] S2. The 2116 type electronic grade glass fiber is immersed in the resin solution prepared in S1 for 36 minutes, then removed and baked in an oven at 160℃ for 5 minutes and then cooled to room temperature to obtain a semi-cured sheet.

[0068] S3. Cut the prepreg obtained in S2 into the same size, two sheets per group, and then stack them with copper foil. Hot press them at a pressure of 2.5MPa and a temperature of 260℃ for 260 minutes to obtain a halogen-free high-frequency copper-clad laminate.

[0069] The preparation process of fluorinated thiol-grafted polybutadiene is as follows:

[0070] 5g of polybutadiene (number average molecular weight of 2000) was weighed and added to 100g of tetrahydrofuran. After dissolving by magnetic stirring, 1.5g of 1H,1H,2H,2H-perfluorododecanethiol and 0.005g of photoinitiator 907 were added. The mixture was reacted for 2h under a nitrogen atmosphere and irradiated with 365nm ultraviolet light. The product was then precipitated in anhydrous ethanol and dried in a vacuum oven at 40℃ for 24h to obtain fluorinated thiol-grafted polybutadiene.

[0071] The styrene-butadiene-styrene copolymer has a number-average molecular weight of 30,000, the active ester curing agent is HPC-8000-65T active ester resin from DIC Corporation of Japan, and the initiator is composed of 2,3-dimethyl-2,3-diphenylbutane and di-tert-butylperoxyisopropylbenzene in a mass ratio of 1:1.

[0072] Comparative Example 2

[0073] A method for manufacturing a halogen-free high-frequency copper-clad laminate, compared with Example 3, is to replace the diamond-based flame-retardant filler in Example 3 with the substance in Comparative Example 1, while the other raw materials and preparation process are the same as in Example 3.

[0074] Comparative Example 3

[0075] A method for manufacturing a halogen-free high-frequency copper-clad laminate, compared with Example 3, is to replace the fluorinated thiol-grafted polybutadiene in Example 3 with polybutadiene with a number average molecular weight of 2000, while the other raw materials and preparation process are the same as in Example 3.

[0076] The halogen-free high-frequency copper-clad laminates obtained in Examples 3-5 and Comparative Examples 2-3 were tested according to the test methods in the patent with authorization announcement number CN116925446B. The dielectric constant and dielectric loss were determined according to IPC TM-650 (2.5.5), the peel strength was determined according to IPC-TM-650 version 2.4.8 "Peel and Impact Test Method for Copper-Clad Laminates", the flame retardancy was tested according to the vertical burning method of UL-94 standard, the thermal conductivity was determined according to ASTM D5470 standard, and the water absorption rate of the copper-clad laminate was tested according to IPC-TM-650 2.6. The test surface size was 50.8mm × 50.8mm, the test temperature was 25℃, and the test time was 24h. The average of three results was taken, and the results are shown in Table 1.

[0077] Table 1

[0078]

[0079]

[0080] As can be seen from the data recorded in Table 1, compared with Comparative Examples 2 and 3, the copper-clad laminates obtained in Examples 3, 4, and 5 have better dielectric properties, peel resistance, flame retardancy, thermal conductivity, and water resistance, and have broad application prospects in high-multilayer high-frequency circuit boards in fields such as communications, automotive millimeter-wave radar, Internet of Things, and automotive electronics.

[0081] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0082] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for manufacturing a halogen-free high-frequency copper-clad laminate, characterized in that, Includes the following steps: S1. Add fluorinated thiol-grafted polybutadiene, styrene-butadiene-styrene copolymer, dicyclopentadiene phenol epoxy resin, toluene, methyl ethyl ketone, and propylene glycol monomethyl ether to a mixer and stir for 30-60 minutes. Then add initiator, active ester curing agent, and diamond-based flame retardant filler and stir for 2-4 hours to obtain resin solution. S2. Immerse the glass in the resin solution prepared in S1 for 30-36 minutes, then remove it and bake it in an oven at 150-160℃ for 5 minutes, then cool it to room temperature to obtain a semi-cured sheet. S3. Cut the prepreg obtained in S2 into the same size, 2-8 sheets per group, and then stack them with copper foil. Hot press them for 260 minutes at a pressure of 1.8-2.5MPa and a temperature of 250-260℃ to obtain halogen-free high-frequency copper-clad laminate. The diamond-based flame-retardant filler is a hyperbranched polyamide grafted with nanodiamonds. The hyperbranched polyamide is obtained by reacting tris(3-aminophenyl)phosphorus oxide and a double-terminated carboxylsiloxane. S1 contains fluorinated mercaptan-grafted polybutadiene, styrene-butadiene-styrene copolymer, initiator, dicyclopentadiene-phenol epoxy resin, reactive ester curing agent, diamond-based flame retardant filler, toluene, methyl ethyl ketone, and propylene glycol monomethyl ether in a mass ratio of 100:50:6:30:5:50-60:80:20:10; The preparation process of diamond-based flame-retardant fillers is as follows: Weigh out tris(3-aminophenyl)phosphine oxide and bi-terminated carboxylsiloxane and add them to a flask. Then add N-methylpyrrolidone, pyridine and triphenyl phosphite. Stir at room temperature for 5-10 min, then add carboxylated nanodiamonds. Disperse by ultrasonication for 30 min, stir at room temperature for 2 h, react at 70℃ for 2 h, and react at 130℃ for 8 h. After the reaction is completed, cool to room temperature, filter, wash the filter cake with acetone and dry to obtain diamond-based flame retardant filler. The preparation process of double-terminated carboxylsiloxanes is as follows: Weigh acrylic acid and add it to a flask. Heat the flask to 40°C. First, add isopropanol chloroplatinic acid solution dropwise, then add 1,1,3,3-tetramethyldisiloxane dropwise. After the addition is complete, raise the temperature to 70°C and stir the reaction for 2-3 hours. Remove isopropanol and unreacted acrylic acid by vacuum distillation to obtain the bi-terminated carboxylsiloxane. The preparation process of fluorinated thiol-grafted polybutadiene is as follows: Polybutadiene was weighed and added to tetrahydrofuran. After dissolving by magnetic stirring, fluorinated thiol and photoinitiator 907 were added. The mixture was reacted for 2 hours under a nitrogen atmosphere and irradiated with 365 nm ultraviolet light. The product was then precipitated in anhydrous ethanol and dried in a vacuum oven at 40 °C for 24 hours to obtain fluorinated thiol-grafted polybutadiene.

2. The method for manufacturing a halogen-free high-frequency copper-clad laminate according to claim 1, characterized in that, The ratio of tris(3-aminophenyl)phosphine oxide, di-terminated carboxysiloxane, N-methylpyrrolidone, pyridine, triphenyl phosphite, and carboxylated nanodiamond is 1.2g:1g:20-40mL:5mL:6mL:0.35-0.44g.

3. The method for manufacturing a halogen-free high-frequency copper-clad laminate according to claim 1, characterized in that, The molar ratio of acrylic acid to 1,1,3,3-tetramethyldisiloxane is 2.1-2.3:

1.

4. The method for manufacturing a halogen-free high-frequency copper-clad laminate according to claim 1, characterized in that, The mass ratio of polybutadiene, tetrahydrofuran, fluorinated mercaptan and photoinitiator 907 is 5:100:0.5-1.5:0.005, and the number average molecular weight of polybutadiene is 2000.

5. The method for manufacturing a halogen-free high-frequency copper-clad laminate according to claim 1, characterized in that, The fluorinated thiols are one or more of the following: 1H,1H,2H,2H-perfluorooctylthiols, 1H,1H,2H,2H-perfluorododecylthiols, and pentafluoropentanethiols.

6. A halogen-free high-frequency copper-clad laminate, characterized in that, It is prepared by the manufacturing method described in any one of claims 1-5.

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