High-heat-resistance, high-flame-retardance and low-dielectric benzoxazine resin and preparation method thereof

Abstract

The invention discloses high-heat-resistance, high-flame-retardancy and low-dielectric benzoxazine resin as shown in a formula (1) and a preparation method thereof, and is characterized in that the preparation method comprises the following steps: adding main chain type benzoxazine resin, DOPO (9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) and a solvent into a reactor provided with a stirrer, a thermometer and a condenser tube, heating to 80-100 DEG C, and reacting for 30-100 minutes; and adjusting the temperature to 100-120 DEG C, and reacting for 30-100 minutes to obtain the benzoxazine resin with high heat resistance, high flame retardance and low dielectric constant. By adopting the preparation method, the prepared benzoxazine resin with high heat resistance, high flame retardance and low dielectric constant has the characteristics of no halogen, high flame retardance, high heat resistance, relatively good toughness, relatively good dielectric property and the like, is particularly suitable for being used as a raw material for a high-frequency and high-speed copper-clad plate, and can also be used in the fields of laminated boards, integrated circuit packaging, high-density internet and the like. # imgabs0 #

Description

Technical Field

[0001] The present invention belongs to organic compounds and their preparation, and relates to a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin and its preparation method. The high heat-resistant, high flame-retardant, low dielectric benzoxazine resin of the present invention (prepared) is particularly suitable for use as a raw material for high-frequency and high-speed copper-clad laminates, and can also be used in laminates, integrated circuit packaging, high-density Internet and other fields. Background Art

[0002] With the rapid development of artificial intelligence, 5G communications, and smart driving, new requirements are constantly being put forward for PCB substrates and base resins, which are important components of electronic products, requiring them to have higher heat resistance, better flame retardancy, and better dielectric properties. Conventional benzoxazine resins such as bisphenol A and bisphenol F are only suitable for the pressing of ordinary copper clad laminates due to their poor heat resistance, low flame retardancy, and slightly poor dielectric properties. They cannot be used on high-frequency and high-speed copper clad laminates. Therefore, people try to further develop and synthesize benzoxazine with high heat resistance, high flame retardancy, and low dielectric properties.

[0003] In order to further improve the heat resistance of benzoxazine resin, in the prior art, CN102702128A discloses "ether bond-containing diamine type fluorenyl benzoxazine", CN102702225A discloses "tetraphenol fluorenyl benzoxazine and preparation method thereof", CN108546272A discloses "Si-O-Ph organic-inorganic hybrid bond cross-linked polybenzoxazine, polybenzoxazine monomer and preparation method thereof", 102584884A discloses "benzoxazine monomer, benzoxazine precursor and low dielectric benzoxazine resin", which introduces fluorenyl, Si-O-Ph hybrid bond, siloxane group and other groups into the benzoxazine resin structure to improve the heat resistance; in order to improve the flame retardancy of benzoxazine resin, CN103755741A discloses "a bisphenol A-monomer containing DOPO" CN108033981A discloses "a phosphorus-containing benzoxazine monomer and a preparation method thereof", CN106928279A discloses "a preparation method of bisphenol A-bisbenzoxazine and a polymer thereof containing bis-DOPO", and 112980135A discloses "a flame retardant-toughened benzoxazine / bio-based phosphide composite material and a preparation method thereof", and introduces DOPO (DOPO is the abbreviation of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), DOPO-HQ [DOPO-HQ is the abbreviation of 10-(2,5-dihydroxyphenyl)-10-hydrogen-9-oxa-10-phosphaphenanthrene-10-oxide], bio-based phosphides and other phosphorus-containing groups into benzoxazine resin to improve the flame retardancy of the resin. In order to improve the dielectric properties, CN107522831A discloses "a novel high temperature resistant and low dielectric silicon-containing benzoxazine and its preparation method", CN112062908A discloses "a low dielectric unsaturated benzoxazine resin composition and preparation method", and CN112142682A discloses "biphenyl type benzoxazine and its preparation method and polybenzoxazine resin", which introduce silicon, unsaturated bonds, biphenyl structures and other groups into the benzoxazine resin structure to improve its dielectric properties. The above-mentioned disclosed technical solutions basically only focus on improving one or two aspects of the performance of benzoxazine resins, and there are few reports on patents that improve comprehensive performance such as heat resistance, dielectric properties and flame retardancy. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the above-mentioned prior art and provide a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin and a preparation method thereof. According to the present invention, a bisphenol-type compound, a diamine-type compound, polyformaldehyde and a catalyst are first reacted at a certain temperature, and when the molecular weight of the product reaches a certain level, a monophenol is added to terminate the reaction to form a main chain benzoxazine resin; and then the resin is reacted with DOPO at a certain temperature, thereby providing a benzoxazine resin having high heat resistance, high flame retardant and low dielectric properties and a preparation method thereof.

[0005] The present invention provides a highly heat-resistant, highly flame-retardant, low-dielectric benzoxazine resin, characterized in that the benzoxazine resin has a chemical structure shown in formula (1):

[0006]

[0007] In formula (1), n ​​is 0 to 10,

[0008] R 1 -CH 2 -、-SO 2 , -O-, -CO-;

[0009] R 2 -CH 2 -、-SO 2 、-C(CH 3 ) 2 -、-C(CH 3 )(C 2 H 5 )-、-C(CF 3 ) 2 -、-CH(CH 3 )-

[0010]

[0011] R 3 -H, -CH 3 、-CH 2 CH=CH 2 ;

[0012] R 4 -H, C 1 ~C 12 Alkyl, -CH=CH 2 、-CH 2 CH=CH 2 , -C 6 H 5 、-NH 2 、-NO 2 , -C 10 H 7

[0013] or -C 6 H 11 .

[0014] Another content of the present invention is: a method for preparing a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin, characterized in that the steps are: in a reactor equipped with a stirrer, a thermometer and a condenser, 100g of a main chain benzoxazine resin, 17-28g of DOPO, and 100g of a solvent are added, the temperature is raised to 80-100°C, and the reaction is carried out for 30-100min; the temperature is then adjusted to 100-120°C, the reaction is carried out for 30-100min, and the temperature is lowered to obtain a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin;

[0015] The main chain benzoxazine resin has a chemical structure as shown in the following formula (2):

[0016]

[0017] In formula (2): n is 0 to 10;

[0018] R 1 -CH 2 -、-SO 2 , -O-, -CO-;

[0019] R 2 -CH 2 -、-SO 2 、-C(CH 3 ) 2 -、-C(CH 3 )(C 2 H 5 )-、-C(CF 3 ) 2 -、-CH(CH 3 )-

[0020]

[0021] R 3 -H, -CH 3 、-CH 2 CH=CH 2 ;

[0022] R 4 -H, C 1 ~C 12 Alkyl, -CH=CH 2 、-CH 2 CH=CH 2 , -C 6 H 5 、-NH 2 、-NO 2 , -C 10 H 7

[0023] or -C6 H 11 ;

[0024] The DOPO is purchased from Shouguang Weidong Co., Ltd. or other commercially available DOPO produced by other enterprises;

[0025] The solvent is one or a mixture of two or more of butanone, toluene, cyclohexanone, propylene glycol monomethyl ether, propylene glycol methyl ether acetate, N,N-dimethylformamide, N,N-dimethylacetamide, and methyl isobutyl ketone;

[0026] In another aspect of the present invention: the preparation method of the main chain type benzoxazine resin is: in a reactor equipped with a stirrer, a thermometer, a condenser and a water separator, add bisphenol compound, diamine compound and paraformaldehyde in a molar ratio of 1:1.1-1.5:2.5-4, then add toluene with a weight of 1-3 times the total mass of the mixture (the total mass of the mixture is: the total mass of the sum of the bisphenol compound, the diamine compound and the paraformaldehyde) and a catalyst with a weight of 1‰-1% of the total weight of the material (the total weight of the material is: the sum of the total mass of the mixture and the weight of toluene), stir evenly, and heat to 60-90°C. ℃ (temperature 1) for 0.5-4h (time 1), and use a water separator to promptly remove the water produced by the reaction from the system, and react at 110-130℃ (temperature 2) for 0.5-2h (time 2); test the molecular weight of the resin, and after reaching the target molecular weight, add 0.2-0.5mol of monophenol, and continue to react at 110-130℃ for 1-3h (time 3); wash the obtained resin (i.e., the reacted material) with 1mol / L NaOH solution, separate the layers, remove the resin layer, wash with deionized water, separate the layers, remove the resin layer, and remove toluene and water with a rotary evaporator to obtain a main chain benzoxazine resin;

[0027] The bisphenol compound is one or a mixture of two or more of bisphenol A, bisphenol F, bisphenol C, 4,4'-dihydroxydiphenyl ether, bisphenol S, bisphenol AF, bisphenol B, bisphenol fluorene, phenolphthalein, bisphenol TMC, bisphenol E, bisphenol M, and tetraphenyl bisphenol A;

[0028] The diamine compound is one or a mixture of two or more of diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfone and diaminobenzophenone;

[0029] The monophenol is a compound having a chemical structure as shown in the following formula (3):

[0030]

[0031] R 5 -H, -C 1 ~C 12 Alkyl, -CH=CH2 、-CH 2 CH=CH 2 , -C 6 H 5 、-NH 2 、-NO 2 , -C 10 H 7

[0032] or -C 6 H 11 ;

[0033] The paraformaldehyde is a mixture of one or more species with a degree of polymerization of 10-100, and the mole number thereof is calculated according to the theoretical mole number of formaldehyde, that is, the mole number = mass × purity ÷ 30;

[0034] The catalyst is one or a mixture of two or more metal halides such as zinc chloride, indium trihalide, ferric chloride, antimony pentachloride, trifluoromethanesulfonate, morpholine trifluoroacetate, aluminum trichloride-nitroalkyl complex, etc.

[0035] Compared with the prior art, the present invention has the following characteristics and beneficial effects:

[0036] (1) The high heat-resistant, high flame-retardant, low-dielectric benzoxazine resin of the present invention adopts part of the oxazine ring in the DOPO (PH bond) open-ring main chain benzoxazine resin structure to obtain a benzoxazine resin with a high phosphorus content of 2-3%. The PN synergy is used to greatly improve the flame retardancy of the resin;

[0037] (2) The high heat-resistant, high flame-retardant, low dielectric benzoxazine resin of the present invention contains a main chain benzoxazine resin structure, which has a relatively long molecular main chain, and the oxazine rings are fixed on the main chain. When the oxazine rings are opened by heat, a large volume chemical structure centered on the molecular main chain is formed, which increases the free volume of the molecule, hinders the molecular vibration, and has better dielectric properties;

[0038] (3) Compared with common benzoxazine resins, the high heat-resistant, high flame-retardant, low-dielectric benzoxazine resin of the present invention has more cross-linking points during curing and a higher cross-linking density, and the molecular groups are all fixed on the main chain without pendant groups, so that the heat resistance of the product is greatly improved;

[0039] (4) The performance parameters of the high heat-resistant, high flame-retardant, low-dielectric benzoxazine resin of the present invention are as follows: heat resistance Td5% ≥ 370°C, Tg ≥ 240°C, dielectric constant ≤ 3.20; dielectric loss ≤ 0.006; flame retardancy reaches UL94V-0 level. It also has the characteristics of high heat resistance, halogen-free flame retardancy, etc., and has excellent comprehensive performance, and can be used as a resin for high-performance copper clad laminates;

[0040] (5) The preparation process of the product of the present invention is simple and easy to operate. The high heat-resistant, high flame-retardant, low dielectric benzoxazine resin of the present invention has the characteristics of being halogen-free, highly flame-retardant, highly heat-resistant, having good toughness, and having good dielectric properties. It is particularly suitable as a raw material for high-frequency and high-speed copper-clad laminates, and can also be used in laminates, integrated circuit packaging, high-density Internet and other fields, and has strong practicality. DETAILED DESCRIPTION

[0041] The following embodiments are intended to further illustrate the present invention, but should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by technicians in this field based on the above-mentioned contents of the present invention still fall within the scope of protection of the present invention.

[0042] Part I Preparation of Main Chain Benzoxazine Resins

[0043] Embodiments 1-1 to 1-6: A method for preparing a main chain benzoxazine resin, comprising the following steps: adding bisphenol compound, diamine compound and paraformaldehyde in a molar ratio of 1:1.1 to 1.5:2.5 to 4 to a reactor equipped with a stirrer, a thermometer, a condenser and a water separator, and then adding toluene in an amount of 1 to 3 times the total mass of the mixture (the total mass of the mixture is the total mass of the bisphenol compound, the diamine compound and the paraformaldehyde) and a catalyst in an amount of 1‰ to 1% of the total mass of the material (the total mass of the material is the sum of the total mass of the mixture and the weight of toluene), stirring evenly, and heating to 60 to 90°C. 0°C (temperature 1) for 0.5-4h (time 1), and use a water separator to promptly remove the water produced by the reaction from the system, and react at 110-130°C (temperature 2) for 0.5-2h (time 2); test the molecular weight of the resin, and after reaching the target molecular weight, add 0.2-0.5mol of monophenol, and continue to react at 110-130°C for 1-3h (time 3); wash the obtained resin (i.e., the reacted material) with 1mol / L NaOH solution, separate the layers, remove the lower resin layer, wash with deionized water, separate the layers, remove the lower resin layer, and remove toluene and water with a rotary evaporator to obtain a main chain benzoxazine resin;

[0044] The bisphenol compound is one or a mixture of two or more of bisphenol A, bisphenol F, bisphenol C, 4,4'-dihydroxydiphenyl ether, bisphenol S, bisphenol AF, bisphenol B, bisphenol fluorene, phenolphthalein, bisphenol TMC, bisphenol E, bisphenol M, and tetraphenyl bisphenol A;

[0045] The diamine compound is one or a mixture of two or more of diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfone and diaminobenzophenone;

[0046] The monophenol is a compound having a chemical structure as shown in the following formula (3):

[0047]

[0048] R 5 -H, -C 1 ~C 12 Alkyl, -CH=CH 2 、-CH 2 CH=CH 2 , -C 6 H 5 、-NH 2 、-NO 2 , -C 10 H 7

[0049] or -C 6 H 11 ;

[0050] The polymerization degree of the paraformaldehyde can be one or a mixture of two or more with a degree of polymerization of 10-100, and its mole number is calculated according to the theoretical formaldehyde mole number, that is, mole number = mass × purity ÷ 30; the paraformaldehyde used in Examples 1-1 to 1-6 is analytically pure granular paraformaldehyde from Merck Chemical with a purity of 95%.

[0051] The catalyst is one or a mixture of two or more metal halides such as zinc chloride, indium trihalide, ferric chloride, antimony pentachloride, trifluoromethanesulfonate, morpholine trifluoroacetate, aluminum trichloride-nitroalkyl complex, etc.

[0052] The specific component raw materials, dosage and process parameters of each example in the preparation method of the main chain benzoxazine resin of Examples 1-1 to 1-6 are shown in Table 1 below.

[0053] Table 1:

[0054]

[0055]

[0056] Part II Preparation of high heat resistance, high flame retardant, low dielectric benzoxazine resin

[0057] Examples 2-1 to 2-6: A method for preparing a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin, comprising the following steps: adding 100 g of a main chain benzoxazine resin (the main chain benzoxazine resin prepared in Examples 1-1 to 1-6, see Table 2 below for details), 17 to 28 g of DOPO, and 100 g of a solvent to a reactor equipped with an agitator, a thermometer, and a condenser, heating to 80 to 100° C. (temperature 4), and reacting for 30 to 100 min (time 4); then adjusting the temperature to 100 to 120° C. (temperature 5), reacting for 30 to 100 min (time 5), and cooling to obtain a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin;

[0058] The specific component raw materials, dosage, process parameters and performance parameters of the high heat-resistant, high flame-retardant and low dielectric benzoxazine resin prepared in each embodiment of Examples 2-1 to 2-6 are shown in Table 2 below.

[0059] Table 2:

[0060]

[0061]

[0062] The technical performance test methods in Table 2 are as follows:

[0063] (1) Glass transition temperature (Tg)

[0064] The determination was carried out by differential scanning calorimetry according to the DSC method specified in 2.4.25 of IPC-TM-650.

[0065] (2) Thermal decomposition temperature (Td)

[0066] The test is carried out according to the method specified in 2.4.26 of IPC-TM-650.

[0067] (3) Flame retardancy

[0068] The test adopts the 5402 horizontal vertical combustion test machine and is carried out in accordance with the test method of the second part of GB / T1303.2-2009.

[0069] (4) Phosphorus content (P%)

[0070] The test adopts SGS internal test method (CQTC-CCL-TOP-001, reference US EPA 3052-1996) and is analyzed by ICP-OES.

[0071] (5) Dielectric constant (Dk)

[0072] The dielectric constant at 10 GHz was measured using the flat plate method according to 2.5.5.9 of IPC-TM-650.

[0073] (6) Dielectric loss factor tangent (Df)

[0074] According to 2.5.5.9 of IPC-TM-650, use the flat plate method to measure the dielectric loss tangent at 10 GHz.

[0075] As can be seen from Table 2, the high heat resistance, high flame retardancy, low dielectric benzoxazine resin obtained by applying the embodiments of the present invention has excellent heat resistance and high flame retardancy. The resin of the present invention can be used in the fields of laminates, integrated circuit packaging, high-frequency and high-speed copper-clad laminates, and high-density Internet, and has broad application prospects.

[0076] In the above embodiments: the percentages used, unless otherwise specified, are all mass (weight) percentages or percentages known to those skilled in the art; the proportions used, unless otherwise specified, are all mass (weight) proportions; and the weights may be in grams or kilograms.

[0077] In the above embodiments, the process parameters (temperature, time, concentration, etc.) in each step and the numerical values ​​of the amounts of each component are ranges, and any point can be applied.

[0078] The technical contents not specifically described in the present invention and the above embodiments are the same as the prior art, and the raw materials are all commercially available products.

[0079] The present invention is not limited to the above embodiments, and all of the contents of the present invention can be implemented and have the above good effects.

Claims

1. A high heat-resistant, high flame-retardant, low dielectric benzoxazine resin, characterized by: The benzoxazine resin has a chemical structure shown in formula (1): In formula (1), n ​​is 0 to 10, R1 is -CH2-, -SO2, -O-, -CO-; R2 is -CH2-, -SO2, -C(CH3)2-, -C(CH3)(C2H5)-, -C(CF3)2-, -CH(CH3)- R3 is -H, -CH3, -CH2CH=CH2; R4 is -H, C1~C 12 Alkyl, -CH=CH2, -CH2CH=CH2, -C6H5, -NH2, -NO2, -C 10 H7 or -C6H 11 .

2. A method for preparing a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin, characterized in that the steps are: in a reactor equipped with a stirrer, a thermometer and a condenser, add 100g of a main chain benzoxazine resin, 17-28g of DOPO, and 100g of a solvent, heat to 80-100°C, and react for 30-100min; then adjust the temperature to 100-120°C, react for 30-100min, and cool to obtain a high heat-resistant, high flame-retardant, low dielectric benzoxazine resin; The main chain benzoxazine resin has a chemical structure as shown in the following formula (2): In formula (2): n is 0 to 10; R1 is -CH2-, -SO2, -O-, -CO-; R2 is -CH2-, -SO2, -C(CH3)2-, -C(CH3)(C2H5)-, -C(CF3)2-, -CH(CH3)- R3 is -H, -CH3, -CH2CH=CH2; R4 is -H, C1~C 12 Alkyl, -CH=CH2, -CH2CH=CH2, -C6H5, -NH2, -NO2, -C 10 H7 or -C6H 11 .

3. The method for preparing the high heat-resistant, high flame-retardant, low dielectric benzoxazine resin according to claim 2, characterized in that: The solvent is one or a mixture of two or more of butanone, toluene, cyclohexanone, propylene glycol monomethyl ether, propylene glycol methyl ether acetate, N,N-dimethylformamide, N,N-dimethylacetamide and methyl isobutyl ketone.

4. The method for preparing the high heat-resistant, high flame-retardant, low dielectric benzoxazine resin according to claim 2 or 3, characterized in that: The preparation method of the main chain benzoxazine resin is as follows: in a reactor equipped with a stirrer, a thermometer, a condenser and a water separator, a bisphenol compound, a diamine compound and a polyformaldehyde in a molar ratio of 1:1.1-1.5:2.5-4 are added, and then toluene with a weight of 1-3 times the total weight of the mixture and a catalyst with a weight of 1‰-1% of the total weight of the material are added, stirred evenly, heated to 60-90°C for reaction for 0.5-4h, and a water separator is used to separate the mixture into a 200 μm column and a 200 μm column. The water produced by the reaction is promptly taken out of the system by a device, and the reaction is carried out at 110-130° C. for 0.5-2 hours; the molecular weight of the resin is tested, and after reaching the target molecular weight, 0.2-0.5 mol of monophenol is added, and the reaction is continued at 110-130° C. for 1-3 hours; the obtained resin is washed with 1 mol / L NaOH solution, layered, the lower resin layer is removed, and then washed with deionized water, layered, the lower resin layer is removed, and toluene and water are removed by a rotary evaporator to obtain a main chain benzoxazine resin; The bisphenol compound is one or a mixture of two or more of bisphenol A, bisphenol F, bisphenol C, 4,4'-dihydroxydiphenyl ether, bisphenol S, bisphenol AF, bisphenol B, bisphenol fluorene, phenolphthalein, bisphenol TMC, bisphenol E, bisphenol M, and tetraphenyl bisphenol A; The diamine compound is one or a mixture of two or more of diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfone and diaminobenzophenone; The monophenol is a compound having a chemical structure as shown in the following formula (3): R5 is -H, -C1~C 12 Alkyl, -CH=CH2, -CH2CH=CH2, -C6H5, -NH2, -NO2, -C 10 H7 or -C6H 11 .

5. The method for preparing the high heat-resistant, high flame-retardant, low dielectric benzoxazine resin according to claim 4, characterized in that: The paraformaldehyde is one or a mixture of two or more having a polymerization degree of 10-100.

6. The method for preparing the high heat-resistant, high flame-retardant, low dielectric benzoxazine resin according to claim 4 or 5, characterized in that: The catalyst is one or a mixture of two or more of zinc chloride, indium trihalide, ferric chloride, antimony pentachloride, trifluoromethanesulfonate, morpholine trifluoroacetate, and aluminum chloride-nitroalkyl complex.

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