Main chain type whole bio-based benzoxazine resin and preparation method thereof, and resin composition for copper-clad plate

Abstract

The preparation method comprises the following steps: adding bio-based bisphenol, bio-based diamine and bio-based aldehyde into a reactor provided with a stirrer, a thermometer, a condenser pipe and a water segregator, adding toluene and a catalyst, uniformly stirring, heating, separating out water generated by a system by using the water segregator while heating, and adding a catalyst into the reactor to obtain the main chain type full-bio-based benzoxazine resin. And when the temperature is raised to 120-140 DEG C, maintaining the reaction for 3-5 hours, adding bio-based monophenol, continuously reacting for 1-3 hours at the temperature, washing and layering the obtained resin by using a 1mol / L NaOH solution, taking the lower resin layer, washing and layering by using deionized water, taking the lower resin layer, and removing methylbenzene and water by using a rotary evaporator to obtain the main chain type full bio-based benzoxazine resin. According to the main chain type full-bio-based benzoxazine resin, bio-based bisphenol, bio-based diamine, bio-based aldehyde and bio-based monophenol are subjected to a reaction to form the benzoxazine resin of a main chain structure, all raw materials participating in the reaction are bio-based raw materials, and the synthesized benzoxazine resin is the full-bio-based benzoxazine resin.

Description

Technical Field

[0001] The present invention relates to the field of copper clad laminates, specifically to a main-chain type all-bio-based benzoxazine resin and its preparation method, and also to a resin composition for copper clad laminates. Background Art

[0002] Bio-based resins use renewable resources such as plant oils, starches, and cellulose as raw materials. During the production process, carbon emissions are much lower than those of traditional petroleum-based resins, which can effectively reduce greenhouse gas emissions, lower the carbon footprint in the industrial field, and contribute to the transformation of the national energy structure and green and low-carbon development.

[0003] Benzoxazine resin is a six-membered heterocyclic compound containing C, N, and O formed by the condensation of phenol, primary amine, and formaldehyde. Under the action of heat or a catalyst, it undergoes ring-opening polymerization to form a nitrogen-containing network structure similar to phenolic resin. The cured product has characteristics such as a low dielectric constant and dielectric loss, low water absorption, high heat resistance, processing dimensional stability, and good flame retardancy, and is one of the suitable raw materials for preparing copper clad laminates. The synthesis raw materials of benzoxazine are usually phenol, bisphenol A, bisphenol F, aniline, diaminodiphenylmethane, diaminodiphenyl ether, paraformaldehyde, etc., which are basically all derived from petroleum cracking products. The synthesized benzoxazine belongs to petroleum-based resin and cannot meet the requirements of green development. Researchers have begun to develop bio-based benzoxazine resins. For example, in patent CN111057050A, phloretic acid and furfurylamine are used as the phenol source and amine source, and reacted with paraformaldehyde to generate a bio-based benzoxazine resin; in patent CN114195803A, dihydroxycoumarin, an amine compound, and paraformaldehyde are reacted to generate a coumarin-based bio-based bifunctional benzoxazine resin; in patent CN118562127A, bisphenolic acid is first synthesized with an alcohol substance to form bisphenolic acid ester, and then it is reacted with paraformaldehyde and bis(trifluoromethyl diaminobiphenyl) to synthesize a bio-based benzoxazine resin with high Tg and intrinsic flame retardancy. In CN115260489A, a bio-based monophenol, a bio-based diamine (Priamine1074), and paraformaldehyde are used to synthesize a bio-based bifunctional benzoxazine resin. Similar patents also include CN113845638A, CN115260425A, etc. However, in such reports, only the phenol source and amine source use bio-based raw materials, but most of the aldehyde substances use paraformaldehyde, and paraformaldehyde still belongs to petroleum-based compounds. Therefore, such benzoxazine resins are not all-bio-based benzoxazine resins. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a main-chain type all-bio-based benzoxazine resin and its preparation method, as well as a resin composition for copper clad laminates.

[0005] To solve the above technical problems, the technical solution of the present invention is: a main-chain type all-bio-based benzoxazine resin, and its innovation lies in: the benzoxazine resin has the chemical structure general formula shown in formula (1): (1) In formula (1): n is 1 to 5, and R1 is any one of -C4H8, -C5H 10 , -C6H 12 or -C 10 H 20 ; R2 is any one of -COCH3, -OCH3 or -CH2CH3.

[0006] A preparation method of the above-mentioned main-chain type all-bio-based benzoxazine resin, and its innovation lies in: including the following steps: First, take a reactor, and install a stirrer, a thermometer, a condenser and a water separator in the reactor; Then, add 0.5 mol of bio-based bisphenol, 0.55 mol to 0.75 mol of bio-based diamine, 1.25 mol to 1.5 mol of bio-based aldehyde into the reactor, and then add toluene with a weight 1 to 3 times that of the total mass of the mixture in the reactor and a catalyst with a weight of 1‰ to 1% of the total weight of the materials. After stirring evenly, heat up, and use the water separator to separate the water generated in the system while heating up. When the temperature rises to 120 - 140 °C, maintain the reaction for 3 - 5 h, then add 0.1 - 0.3 mol of bio-based monophenol to the reactor, and continue to react at this temperature for 1 - 3 h to obtain a resin mixture; Finally, wash the obtained resin mixture with 1 mol / L NaOH solution, layer it, and take out the lower resin layer after layering. Then, wash the lower resin layer with deionized water for a second time, layer it, and also take out the lower resin layer after the second layering. Then, use a rotary evaporator to remove toluene and water in the lower resin layer after the second layering, and the required main-chain type all-bio-based benzoxazine resin is obtained.

[0007] Furthermore, the bio-based bisphenol is polydatin; the bio-based diamine is any one or a mixture of several of butanediamine, pentanediamine, hexanediamine, decanediamine; the bio-based aldehyde is benzaldehyde; the catalyst is any one or a mixture of several of zinc chloride, indium trihalide, ferric trichloride, antimony pentachloride, trifluoromethanesulfonate, morpholine trifluoroacetate, sodium hydroxide; the bio-based monophenol is any one or a mixture of several of p-hydroxyacetophenone, guaiacol, 4-ethylphenol.

[0008] A resin composition for a copper clad laminate, the innovation of which lies in: the resin composition for a copper clad laminate is prepared by mixing 50 parts by mass of the above-mentioned main-chain type all-bio-based benzoxazine resin, 20-30 parts by mass of DCPD epoxy resin, 10-20 parts by mass of maleimide resin, 0.1-0.5 parts by mass of imidazole catalyst, 60-80 parts by mass of filler, and 60-100 parts by mass of solvent evenly at 30-50 °C.

[0009] Further, the solid content of the resin composition for a copper clad laminate is 58% - 75%.

[0010] Further, the DCPD epoxy resin has the chemical structural formula shown in formula (2): The maleimide resin has the general chemical structural formula shown in formula (3): In formula (3): R3 and R4 are any one of -H, -CH3, -C2H5; The imidazole catalyst is any one or a mixture of two or more of imidazole, 2-methylimidazole, 1-methylimidazole, 1,2-dimethylimidazole, 1,3-dimethylimidazole, 2,4-dimethylimidazole; The filler is any one or a mixture of two or more of montmorillonite, calcium carbonate, magnesium hydroxide, zinc borate, talc, aluminum hydroxide, kaolin, barium sulfate, silicon dioxide, silica powder, mica powder, hollow glass microspheres, fumed silica; The solvent is any one or a mixture of two or more of methyl ethyl ketone, toluene, xylene, cyclohexanone, propylene glycol monomethyl ether, propylene glycol methyl ether acetate, N,N-dimethylformamide, N,N-dimethylacetamide, methyl isobutyl ketone.

[0011] The advantages of the present invention are as follows: The main-chain type all-bio-based benzoxazine resin of the present invention is formed by reacting bio-based bisphenol, bio-based diamine, bio-based aldehyde, and bio-based monophenol to form a benzoxazine resin with a main-chain structure. All raw materials participating in the reaction are bio-based raw materials, and the synthesized benzoxazine resin is an all-bio-based benzoxazine resin.

[0012] Both the phenol source and the amine source of the main-chain type all-bio-based benzoxazine resin of the present invention are difunctional compounds. The all-bio-based benzoxazine resin formed by their reaction is a main-chain type benzoxazine resin, and it has good heat resistance, Tg≥200 °C; Td5%≥325 °C; at the same time, this structure has a long molecular main chain, and the oxazine rings are all fixed on the main chain. When the oxazine rings are thermally ring-opened, a large-volume chemical structure centered on the molecular main chain is formed, increasing the free volume of the molecule, making the molecular vibration blocked, and the dielectric properties are more excellent.

[0013] In the resin composition for copper clad laminates of the present invention, DCPD epoxy resin with good dielectric properties is introduced. Since its structure contains a non-polar dicyclopentadiene skeleton, the free volume of the molecule is increased, resulting in further reduction of the dielectric constant and dielectric loss of the product.

[0014] In the resin composition for copper clad laminates of the present invention, maleimide resin with good structural symmetry and rigidity is introduced, further reducing the dielectric constant and dielectric loss of the product; at the same time, due to the introduction of a highly heat-resistant imide ring, the heat resistance of the product is further improved.

[0015] The resin composition for copper clad laminates of the present invention, after pressing: Tg ≥ 220 °C, Td5% ≥ 380 °C; dielectric constant ≤ 3.3 (10 GHz); dielectric loss ≤ 0.008 (10 GHz); it has the characteristics of high heat resistance, low dielectric constant, low dielectric loss, etc.

[0016] The main-chain type all-bio-based benzoxazine resin of the present invention can replace the existing petroleum-based benzoxazine resin for the preparation of resin compositions for high-performance copper clad laminates. Detailed Description of the Invention

[0017] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following combines preferred embodiments to detail the specific implementation manners, structures, features and their effects according to the present invention as follows.

[0018] The main-chain type all-bio-based benzoxazine resin of the present invention has the general chemical structural formula shown in Formula (1): In Formula (1): n is 1 - 5, R1 is any one of -C4H8, -C5H 10 , -C6H 12 or -C 10 H 20 ; R2 is any one of -COCH3, -OCH3 or -CH2CH3.

[0019] The above-mentioned main-chain type all-bio-based benzoxazine resin is prepared through the following steps: First, take a reactor, and install a stirrer, a thermometer, a condenser and a water separator in the reactor.

[0020] Then, add 0.5 mol of bio-based bisphenol, 0.55 mol - 0.75 mol of bio-based diamine, and 1.25 mol - 1.5 mol of bio-based aldehyde to the reactor. The bio-based bisphenol is polydatin, and the bio-based diamine is any one or a mixture of several of butanediamine, pentanediamine, hexanediamine, and decanediamine, and the bio-based aldehyde is benzaldehyde.

[0021] Then, toluene with a weight 1 to 3 times that of the total mass of the mixture in the reactor and a catalyst with a weight of 1‰ to 1% of the total weight of the materials are added. The catalyst is any one or a mixture of several of zinc chloride, indium trihalide, ferric trichloride, antimony pentachloride, trifluoromethanesulfonate, morpholine trifluoroacetate, and sodium hydroxide. After stirring evenly, the temperature is raised, and the water generated in the system is separated with a water separator while heating. When the temperature rises to 120 - 140°C, the reaction is maintained for 3 - 5 h. Then, 0.1 - 0.3 mol of bio-based monophenol is added to the reactor. The bio-based monophenol is any one or a mixture of several of p-hydroxyacetophenone, guaiacol, and 4-ethylphenol. The reaction is continued at this temperature for 1 - 3 h to obtain a resin mixture.

[0022] Finally, the obtained resin mixture is washed with 1 mol / L NaOH solution, layered, and the lower resin layer is taken out after layering. Then, the lower resin layer is washed and layered with deionized water again, and the lower resin layer after the second layering is also taken out. Then, toluene and water in the lower resin layer after the second layering are removed with a rotary evaporator to obtain the required main-chain type all-bio-based benzoxazine resin.

[0023] Table 1 shows the raw material dosages (unit: g), process parameters, and technical properties of the main-chain type all-bio-based benzoxazine resin prepared in Examples 1-1 to 1-4: Table 1 The main-chain type all-bio-based benzoxazine resin prepared in 1-1 to 1-4 in Table 1 is cured according to the program of 140°C for 1 h, 160°C for 1 h, 180°C for 1 h, and 200°C for 2 h to make a casting body of 50 mm × 50 mm × 0.8 mm, and Dk / Df is tested.

[0024] A resin composition for a copper clad laminate is prepared using the above-prepared main-chain type all-bio-based benzoxazine resin. The resin composition for a copper clad laminate is prepared by mixing 50 parts by mass of the above main-chain type all-bio-based benzoxazine resin, 20 - 30 parts by mass of DCPD epoxy resin, 10 - 20 parts by mass of maleimide resin, 0.1 - 0.5 parts by mass of an imidazole catalyst, 60 - 80 parts by mass of a filler, and 60 - 100 parts by mass of a solvent and stirring evenly at 30 - 50°C.

[0025] The solid content of the resin composition for a copper clad laminate is 58% - 75%. The definition of the solid content is the weight percentage of the solid content in the solution in the total solution.

[0026] The DCPD epoxy resin has the chemical structural formula shown in Formula (2): Specifically, the DCPD epoxy resin is selected from one or a mixture of two of DFE228 and DFE228H of Sichuan Dongcai Science & Technology Group Co., Ltd.

[0027] The maleimide resin has the general chemical structure formula shown in Formula (3): In Formula (3): R3 and R4 are any one of -H, -CH3, and -C2H5. Specifically, the maleimide resin is selected from one or a mixture of two or more of DFE930, DFE936, and DFE939 of Sichuan Dongcai Science & Technology Group Co., Ltd.

[0028] The imidazole catalyst is any one or a mixture of two or more of imidazole, 2-methylimidazole, 1-methylimidazole, 1,2-dimethylimidazole, 1,3-dimethylimidazole, and 2,4-dimethylimidazole.

[0029] The filler is any one or a mixture of two or more of montmorillonite, calcium carbonate, magnesium hydroxide, zinc borate, talc, aluminum hydroxide, kaolin, barium sulfate, silica, silica powder, mica powder, hollow glass microspheres, and fumed silica.

[0030] The solvent is any one or a mixture of two or more of methyl ethyl ketone, toluene, xylene, cyclohexanone, propylene glycol monomethyl ether, propylene glycol methyl ether acetate, N,N-dimethylformamide, N,N-dimethylacetamide, and methyl isobutyl ketone.

[0031] Table 2 is the table of the dosage of the formula raw materials of the resin composition for the copper clad laminate in Examples 2-1 to 2-4 (unit: g): Table 2 After preparing the resin composition for the copper clad laminate, the preparation of the prepreg and the copper clad laminate is carried out.

[0032] Specifically, for the preparation of the prepreg: Select an E-glass cloth that is flat, smooth, and has a thickness of 0.2 mm. After impregnating it in the above-mentioned resin composition (solution) for the copper clad laminate, take it out, and then bake it in an oven at 130-170°C for 4-7 minutes to obtain the required prepreg. The resin weight percentage content of the prepreg is 62% - 68%.

[0033] Preparation of copper clad laminate: Cut and stack the above-mentioned prepregs, cover copper foil on both sides or one side of the prepregs, then place them in a hot press. Keep the heating rate at 1 - 3 °C / min. After reaching the temperature, press at a pressure of 0.2 - 1 MPa and a temperature of 80 - 150 °C for 1 - 3 hours, then continue to heat up, keep the heating rate at 1 - 3 °C / min. After reaching the temperature, press at a pressure of 0.2 - 3 MPa and a temperature of 150 - 250 °C for 1 - 4 hours to obtain the product. The RC of the board is 60 ± 2%.

[0034] The technical performance of the copper clad laminate prepared by the present invention is shown in Table 3 below: Table 3 The technical performance test methods in Tables 2 and 3 are as follows: (1) Dielectric constant According to IPC-TM-650, use the flat plate method in 2.5.5.9 to measure the dielectric constant at 10 GHz.

[0035] (2) Dielectric loss tangent According to IPC-TM-650, use the flat plate method in 2.5.5.9 to measure the dielectric loss tangent at 10 GHz.

[0036] (3) Glass transition temperature (Tg) According to differential scanning calorimetry, measure according to the DSC method specified in IPC-TM-650 2.4.25.

[0037] (4) Thermal decomposition temperature (Td) Measure according to the method specified in IPC-TM-650 2.4.26.

[0038] As can be seen from Table 3, the board obtained by applying the examples of the present invention has excellent heat resistance, low dielectric constant and dielectric loss factor. The resin composition of the copper clad laminate of the present invention can be used in fields such as laminates, integrated circuit packages, high-frequency high-speed copper clad laminates, high-density Internet, artificial intelligence, etc., and has broad application prospects.

[0039] In the above examples: Among the percentage ratios used, those not specifically indicated are mass (weight) percentage ratios or percentage ratios well-known to those skilled in the art; among the ratios used, those not specifically indicated are mass (weight) ratios; the weight parts can all be grams or kilograms.

[0040] In the above examples: For the process parameters (temperature, time, pressure, etc.) and the numerical values of the dosages of each component in each step that are in the form of ranges, any point can be applicable.

[0041] The content of the present invention and the technical content not specifically described in the above embodiments are the same as the prior art, and all the raw materials are commercially available products.

[0042] The main-chain type all-bio-based benzoxazine resin of the present invention is prepared by reacting a bio-based bisphenol (polydatin is obtained from the plant Reynoutria japonica), bio-based diamines (putrescine, also known as butanediamine, is obtained by enzymatic conversion; cadaverine is obtained from vegetable oil or polysaccharide; hexanediamine is extracted from waste cooking oil; sebac diamine is obtained from castor oil), bio-based aldehydes (benzaldehyde comes from hyacinth, citronella, cinnamon, iris, cistus), and bio-based monophenols (4-hydroxyacetophenone is obtained from the stems and leaves of Artemisia scoparia of the Compositae family; guaiacol is the main component of wood tar and is obtained from guaiac resin, pine oil, etc.; 4-ethylphenol is derived from eggs, European cranberries, pork, whisky, coffee, etc.) to form a benzoxazine resin with a main-chain structure. All the raw materials participating in the reaction are bio-based raw materials, and the synthesized benzoxazine resin is an all-bio-based benzoxazine resin.

[0043] Both the phenol source and the amine source of the main-chain type all-bio-based benzoxazine resin of the present invention are difunctional compounds. The all-bio-based benzoxazine resin formed by their reaction is a main-chain type benzoxazine resin, and it has good heat resistance (Tg≥200°C; Td5%≥325°C). At the same time, this structure has a relatively long molecular main chain, and the oxazine rings are all fixed on the main chain. When the oxazine rings are thermally ring-opened, a large-volume chemical structure centered on the molecular main chain is formed, increasing the free volume of the molecule, making the molecular vibration blocked, and the dielectric properties are more excellent.

[0044] The DCPD epoxy resin with good dielectric properties is introduced into the resin composition for copper clad laminates of the present invention. Because its structure contains a non-polar dicyclopentadiene skeleton, the free volume of the molecule is increased, and the dielectric constant and dielectric loss of the product are further reduced.

[0045] The maleimide resin with good structural symmetry and rigidity is introduced into the resin composition for copper clad laminates of the present invention, making the dielectric constant and dielectric loss of the product further reduced. At the same time, due to the introduction of a highly heat-resistant imide ring, the heat resistance of the product is further improved.

[0046] The resin composition for copper clad laminates of the present invention, after pressing: Tg≥220°C, Td5%≥380°C; dielectric constant≤3.3 (10 GHz); dielectric loss≤0.008 (10 GHz); it has the characteristics of high heat resistance, low dielectric constant, and low dielectric loss.

[0047] As described above, it is only the preferred embodiment of the present invention and does not impose any formal restrictions on the present invention. Although the present invention has been disclosed above with the preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments of equivalent changes within the scope of the technical solution of the present invention by using the technical content disclosed above. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A main-chain type all-bio-based benzoxazine resin, characterized in that: The benzoxazine resin has the general chemical structure formula shown in formula (1): In formula (1): n is from 1 to 5, and R1 is any one of -C4H8, -C5H 10 , -C6H 12 or -C 10 H 20 ; and R2 is any one of -COCH3, -OCH3 or -CH2CH3.

2. A method for preparing the main-chain type all-bio-based benzoxazine resin according to claim 1, characterized in that: It includes the following steps: First, take a reactor, in which a stirrer, a thermometer, a condenser and a water separator are installed; Then, add 0.5 mol of bio-based bisphenol, 0.55 mol - 0.75 mol of bio-based diamine, 1.25 mol - 1.5 mol of bio-based aldehyde into the reactor, and then add toluene with a weight 1 - 3 times that of the total mass of the mixture in the reactor and a catalyst with a weight of 1‰ - 1% of the total weight of the materials. After stirring evenly, raise the temperature, and while raising the temperature, use the water separator to separate the water generated in the system. When the temperature rises to 120 - 140 °C, maintain the reaction for 3 - 5 h, then add 0.1 - 0.3 mol of bio-based monophenol into the reactor, and continue to react at this temperature for 1 - 3 h to obtain a resin mixture; Finally, wash the obtained resin mixture with 1 mol / L NaOH solution, layer it, and take out the lower resin layer after layering. Then, wash the lower resin layer with deionized water for secondary washing and layering, and also take out the lower resin layer after secondary layering. Then, use a rotary evaporator to remove toluene and water in the lower resin layer after secondary layering, and thus obtain the required main-chain type all-bio-based benzoxazine resin.

3. The main-chain type all-bio-based benzoxazine resin according to claim 2, characterized in that: The bio-based bisphenol is polydatin; the bio-based diamine is any one or a mixture of several of butanediamine, pentanediamine, hexanediamine, decanediamine; the bio-based aldehyde is benzaldehyde; the catalyst is any one or a mixture of several of zinc chloride, indium trihalide, ferric trichloride, antimony pentachloride, trifluoromethanesulfonate, morpholine trifluoroacetate, sodium hydroxide; the bio-based monophenol is any one or a mixture of several of p-hydroxyacetophenone, guaiacol, 4-ethylphenol.

4. A resin composition for a copper clad laminate, characterized in that: The resin composition for copper clad laminate is prepared by mixing 50 parts by mass of the main-chain type all-bio-based benzoxazine resin described in claim 1, 20 - 30 parts by mass of DCPD epoxy resin, 10 - 20 parts by mass of maleimide resin, 0.1 - 0.5 parts by mass of imidazole catalyst, 60 - 80 parts by mass of filler and 60 - 100 parts by mass of solvent evenly at 30 - 50 °C.

5. The resin composition for a copper clad laminate according to claim 4, characterized in that: The solid content of the resin composition for copper clad laminate is 58% - 75%.

6. The resin composition for a copper clad laminate according to claim 4, characterized in that: The DCPD epoxy resin has the chemical structural formula shown in formula (2): The maleimide resin has the general chemical structure formula shown in formula (3): In formula (3): R3 and R4 are any one of -H, -CH3, -C2H5; The imidazole catalyst is any one or a mixture of two or more of imidazole, 2-methylimidazole, 1-methylimidazole, 1,2-dimethylimidazole, 1,3-dimethylimidazole, 2,4-dimethylimidazole; The filler is any one or a mixture of two or more of montmorillonite, calcium carbonate, magnesium hydroxide, zinc borate, talc, aluminum hydroxide, kaolin, barium sulfate, silica, silica powder, mica powder, hollow glass microspheres, fumed silica; The solvent is any one or a mixture of two or more of methyl ethyl ketone, toluene, xylene, cyclohexanone, propylene glycol monomethyl ether, propylene glycol methyl ether acetate, N,N-dimethylformamide, N,N-dimethylacetamide, and methyl isobutyl ketone.

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