Low-dielectric resin composition, metal-clad laminated board and preparation method and application of low-dielectric resin composition and metal-clad laminated board

Abstract

The invention provides a low-dielectric resin composition, a metal-clad laminated board and a preparation method and application thereof, and relates to the technical field of resin. The low-dielectric resin composition is prepared from the following components in parts by weight: 60 to 120 parts of low-dielectric bismaleimide resin, 60 to 120 parts of polycyclic aromatic compound containing unsaturated carbon-carbon double bonds, 5 to 15 parts of flame retardant, 80 to 150 parts of filling material, 5 to 12 parts of flexibilizer, 10 to 30 parts of cross-linking agent and 0.2 to 3 parts of initiator. The metal-clad plate material in the circuit board manufactured by using the low-dielectric resin composition has excellent properties of low dielectric property and high heat resistance, heat resistance and mechanical property, and is suitable for manufacturing a high-frequency and high-speed printed circuit board.

Description

Technical Field

[0001] The present invention relates to the field of resin technology, and in particular to a low-dielectric resin composition, a metal-clad laminate, and a preparation method and application thereof. Background Art

[0002] Traditional substrates like resins contain a large number of polar groups, resulting in high dielectric constants and dielectric losses, making them difficult to meet the low-loss, high-speed transmission requirements of high-frequency communications. Furthermore, these materials have low glass transition temperatures, making them susceptible to deformation or degradation in high-temperature environments, impacting the reliability and lifespan of electronic products. Therefore, selecting a resin with excellent heat resistance and dielectric properties is crucial.

[0003] With the rapid development of the electronics industry, the demand for high-performance resin materials is growing. Bismaleimide resin (BMI) has become a key component of the new generation of high-performance composite materials due to its excellent thermal stability, mechanical properties and electrical insulation. However, as electronic devices develop towards higher performance and smaller size, certain properties of traditional BMI resins can no longer meet higher requirements. In order to further improve the comprehensive performance of BMI resins, divinyl compounds are innovatively introduced into them. This modification not only retains the original excellent properties of BMI resins, but also gives them new functions and advantages, bringing new breakthroughs to the field of electronic materials.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The present invention provides a low-dielectric resin composition, a metal-clad laminate, and methods for preparing and applying the same. The metal-clad laminate material used in circuit boards made from the low-dielectric resin composition exhibits excellent low dielectric properties and high heat resistance, as well as excellent heat resistance and mechanical properties, making it suitable for the production of high-frequency, high-speed printed circuit boards (PCBs).

[0006] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are adopted:

[0007] In a first aspect, the present invention provides a low dielectric resin composition, comprising the following components in parts by weight:

[0008]

[0009] Preferably, the low dielectric bismaleimide resin includes any one or a combination of at least two of the bismaleimide resins shown in the following formula I:

[0010]

[0011] Wherein, X is selected from any one of the following groups:

[0012]

[0013] Wherein, R1 to R9 are each independently selected from any one of H, a halogen atom, a methyl group or an ethyl group;

[0014] Here, m is 1 to 20, and n is 1 to 20.

[0015] Preferably, the number average molecular weight of the low dielectric bismaleimide resin is 500 to 12,000, preferably 700 to 5,000.

[0016] Preferably, the dielectric constant Dk of the low-dielectric bismaleimide resin is 3.5-4.0; the dielectric loss Df of the low-dielectric bismaleimide resin is 1‰-1.5‰.

[0017] Preferably, the glass transition temperature Tg of the low dielectric bismaleimide resin is 250-350°C.

[0018] Preferably, the polycyclic aromatic compound containing unsaturated carbon-carbon double bonds includes any one or a combination of at least two of the compounds represented by the following formula II:

[0019]

[0020] Wherein, Y is selected from any one of the following groups:

[0021]

[0022] Preferably, the polycyclic aromatic compound containing unsaturated carbon-carbon double bonds includes 9,9-bis(4-vinylbenzyl)-9H-fluorene and / or 2,8-bis(4-vinylbenzyl)chrysanthene.

[0023] Preferably, the flame retardant includes a phosphorus-containing flame retardant, and the phosphorus-containing flame retardant includes any one or a combination of at least two of the phosphorus-containing flame retardants shown in the following formula III:

[0024]

[0025] Wherein, R is selected from C1 to C6 linear or branched alkyl groups.

[0026] Preferably, the phosphorus-containing flame retardant includes 1,4-bis(diphenylphosphino)butane.

[0027] Preferably, the filler material comprises synthetic silica and / or spherical silica, preferably spherical silica.

[0028] Preferably, the particle size of the filling material is 0.1-10 μm.

[0029] Preferably, the purity of the filling material is above 99.5%.

[0030] Preferably, the toughening agent comprises any one or a combination of at least two of polybutadiene, styrene-butadiene block copolymer, styrene-butadiene-styrene triblock copolymer, hydrogenated styrene-butadiene-styrene block copolymer or maleic anhydride grafted styrene-butadiene-styrene block copolymer elastomer.

[0031] Preferably, the cross-linking agent includes any one of pentaerythritol tetraacrylate, tricyclodecane dimethanol diacrylate or triallyl isocyanurate resin, or a combination of at least two thereof.

[0032] Preferably, the initiator includes any one of azobisisobutyronitrile, azobis(2-isopropyl)butyronitrile, azobisadiponitrile, dibenzoyl peroxide, dimethylbenzoyl peroxide, diisopropyl peroxide, dicumyl peroxide, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicyclohexyl peroxide, benzoic acid peroxide, tert-butyl peroxide, butylbenzoic acid peroxide or tert-butylbenzoic acid peroxide, or a combination of at least two thereof.

[0033] Preferably, the low dielectric resin composition further comprises 80 to 160 parts of a solvent.

[0034] Preferably, the solvent includes any one of toluene, butanone, acetone, dimethylformamide, methyl ethyl ketone or propylene glycol methyl ether, or a combination of at least two thereof.

[0035] In a second aspect, the present invention provides a method for preparing the low dielectric resin composition according to the first aspect, the preparation method comprising:

[0036] The low dielectric bismaleimide resin, a polycyclic aromatic compound containing unsaturated carbon-carbon double bonds, a flame retardant, a filling material, a toughening agent, a crosslinking agent and an initiator are mixed to obtain the low dielectric resin composition.

[0037] Preferably, the mixing method includes: dissolving a low-dielectric bismaleimide resin, a polycyclic aromatic compound containing unsaturated carbon-carbon double bonds, a flame retardant, a filler, a toughening agent, a crosslinking agent and an initiator in a solvent to obtain the low-dielectric resin composition.

[0038] In a third aspect, the present invention provides a metal-clad laminate comprising a prepreg and a metal foil; the prepreg comprises glass fiber cloth and a low-dielectric resin; wherein the low-dielectric resin is formed by curing the low-dielectric resin composition described in the first aspect.

[0039] In a fourth aspect, the present invention provides a method for preparing the metal-clad laminate, the method comprising:

[0040] Applying the low dielectric resin composition on the glass fiber cloth and semi-curing it to obtain the prepreg;

[0041] The prepreg and the metal foil are stacked and pressed to obtain the metal-clad laminate.

[0042] Preferably, the coating amount of the low dielectric resin composition is 140 to 180 g / m 2 .

[0043] Preferably, the coating line speed is 8 to 25 m / min.

[0044] Preferably, the semi-curing temperature is 110-230° C., and the semi-curing time is 3-6 minutes.

[0045] Preferably, the pressing pressure is 70-600 psi, the pressing temperature is 70-240° C., the pressing vacuum is 0.02-0.1 MPa, and the pressing time is 50-200 min.

[0046] In a fifth aspect, the present invention provides a use of the low dielectric resin composition as described in the first aspect, or the metal-clad laminate as described in the third aspect, in the preparation of a high-frequency and high-speed printed circuit board.

[0047] In a sixth aspect, the present invention provides a high-frequency and high-speed printed circuit board, comprising the low-dielectric resin composition as described in the first aspect, or the metal-clad laminate as described in the third aspect.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] (1) The present invention introduces a bismaleimide resin with a specific structure. The molecular chain of the bismaleimide resin contains rigid groups such as benzene rings and imide heterocycles. The presence of these rigid groups effectively restricts the movement of the molecular chain, thereby improving the thermal stability of the resin and reducing polarization, thereby ensuring the stability of the dielectric constant. At the same time, its high cross-linking density further enhances the reliability of the dielectric properties and reduces performance fluctuations caused by changes in temperature, humidity, or frequency.

[0050] (2) The present invention introduces a multifunctional bismaleimide resin and a polycyclic aromatic compound containing unsaturated double bonds into the low dielectric resin composition, thereby significantly improving the overall performance of the composite material, especially the heat resistance and dielectric properties, having a higher glass transition temperature (Tg) and thermal decomposition temperature, and being able to maintain good physical and mechanical properties under high temperature environments. DETAILED DESCRIPTION

[0051] Unless otherwise defined herein, scientific and technological terms used in conjunction with the present invention shall have the meanings commonly understood by those of ordinary skill in the art. The meaning and scope of the terms should be clear, however, in the case of any potential ambiguity, the definitions provided herein take precedence over any dictionary or external definitions. In this application, unless otherwise stated, the use of "or" means "and / or". In addition, the use of the term "including" and other forms is non-limiting.

[0052] It should be noted that the following description sets forth specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of other ways than those described herein, and those skilled in the art may make similar generalizations without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0053] Below in conjunction with embodiment and example, embodiment of the present invention is described in detail, but those skilled in the art will appreciate that the following embodiment and example are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiment in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work premise all fall within the scope of protection of the present invention. Unspecified conditions are carried out according to the conditions of normal conditions or manufacturer's recommendations. Reagents used or instruments not specified by the manufacturer are conventional products that can be purchased commercially.

[0054] In a first aspect, the present invention provides a low dielectric resin composition, comprising the following components in parts by weight:

[0055]

[0056] In the present invention, a low-dielectric bismaleimide resin and a polycyclic aromatic compound containing an unsaturated carbon-carbon double bond are introduced into the low-dielectric resin composition. The advantages of the two are as follows: 1. Chemical synergy: The carbon-carbon double bonds in the polycyclic aromatic compound containing an unsaturated carbon-carbon double bond can undergo thermal polymerization with the maleimide group of the low-dielectric bismaleimide resin to form a dense three-dimensional cross-linked network, thereby enhancing thermal stability and inhibiting the movement of molecular segments, thereby reducing dielectric loss at high temperatures. 2. Structural optimization: The rigid skeleton of the polycyclic aromatic compound has high rigidity and low polarity. After being embedded in the cross-linked network of the low-dielectric bismaleimide resin, the rigid skeleton hinders the high-temperature movement of the molecular chain, the glass transition temperature is increased simultaneously, and the polycyclic aromatic compound reduces dipole polarization, reducing the dielectric constant and dielectric loss. 3. Compatibility: The polycyclic aromatic compound can be combined with the bismaleimide resin molecular chain through π-π interaction, reducing phase separation, forming a homogeneous structure, avoiding local electric field concentration caused by interface defects, and inhibiting dielectric loss.

[0057] Therefore, the low-dielectric bismaleimide resin and the polycyclic aromatic compound containing unsaturated carbon-carbon double bonds cooperate with each other, thereby significantly improving the overall performance of the composite material, improving the heat resistance and dielectric properties of the resin composition, having a higher glass transition temperature (Tg) and thermal decomposition temperature, and being able to maintain good physical and mechanical properties under high temperature environments.

[0058] As an optional embodiment, the content of low dielectric bismaleimide resin in the low dielectric resin composition is 60 to 120 parts, for example, it can be 60 parts, 62 parts, 64 parts, 65 parts, 66 parts, 68 parts, 70 parts, 72 parts, 74 parts, 75 parts, 76 parts, 78 parts, 80 parts, 82 parts, 84 parts, 85 parts, 86 parts, 88 parts, 90 parts, 92 parts, 94 parts, 95 parts, 96 parts, 98 parts, 100 parts, 102 parts, 104 parts, 105 parts, 106 parts, 108 parts, 110 parts, 112 parts, 114 parts, 115 parts, 116 parts, 118 parts, 120 parts, etc.

[0059] As an optional embodiment, the content of the polycyclic aromatic compound containing unsaturated carbon-carbon double bonds in the low dielectric resin composition is 60 to 120 parts, for example, it can be 60 parts, 62 parts, 64 parts, 65 parts, 66 parts, 68 parts, 70 parts, 72 parts, 74 parts, 75 parts, 76 parts, 78 parts, 80 parts, 82 parts, 84 parts, 85 parts, 86 parts, 88 parts, 90 parts, 92 parts, 94 parts, 95 parts, 96 parts, 98 parts, 100 parts, 102 parts, 104 parts, 105 parts, 106 parts, 108 parts, 110 parts, 112 parts, 114 parts, 115 parts, 116 parts, 118 parts, 120 parts, etc.

[0060] As an optional embodiment, the content of the flame retardant in the low dielectric resin composition is 5 to 15 parts, for example, it can be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, etc.

[0061] As an optional embodiment, the content of filling material in the low dielectric resin composition is 80 to 150 parts, for example, it can be 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 105 parts, 110 parts, 115 parts, 120 parts, 125 parts, 130 parts, 135 parts, 140 parts, 145 parts, 150 parts, etc.

[0062] As an optional embodiment, the content of the toughening agent in the low dielectric resin composition is 5 to 12 parts, for example, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, etc.

[0063] As an optional embodiment, the content of the crosslinking agent in the low dielectric resin composition is 10 to 30 parts, for example, it can be 10 parts, 12 parts, 14 parts, 15 parts, 16 parts, 18 parts, 20 parts, 22 parts, 24 parts, 25 parts, 26 parts, 28 parts, 30 parts, etc.

[0064] As an optional embodiment, the content of the initiator in the low dielectric resin composition is 0.2 to 3 parts, for example, it can be 0.2 parts, 0.4 parts, 0.6 parts, 0.8 parts, 1 part, 1.2 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.8 parts, 2 parts, 2.2 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.8 parts, 3 parts, etc.

[0065] As an optional embodiment, the low dielectric bismaleimide resin includes any one or a combination of at least two of the bismaleimide resins shown in the following formula I:

[0066] Formula I.

[0067] As an optional embodiment, X is selected from any one of the following groups:

[0068]

[0069] As an optional embodiment, R1, R2, R1, R3, R4, R5, R6, R7, R8 and R9 are each independently selected from any one of H, a halogen atom, a methyl group or an ethyl group; and R1, R2, R1, R3, R4, R5, R6, R7, R8, R9 may be the same or different.

[0070] As an optional embodiment, m is 1 to 20, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, etc.

[0071] As an optional embodiment, n is 1 to 20, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, etc.

[0072] As an optional embodiment, the halogen atom includes F, Cl, B or I.

[0073] As a preferred embodiment, the number average molecular weight Mn of the low dielectric bismaleimide resin is 500-12000, for example, it can be 500, 600, 700, 800, 900, 1000, 1200, 1400, 1600, 1800, 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000, 7000, 8000, 9000, 10000, 11000, 12000, etc.

[0074] As a more preferred embodiment, the number average molecular weight Mn of the low dielectric bismaleimide resin is 700 to 5000.

[0075] As a preferred embodiment, the dielectric constant Dk of the low-dielectric bismaleimide resin is 3.5 to 4.0, for example, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, etc.

[0076] As a preferred embodiment, the dielectric loss Df of the low dielectric bismaleimide resin is 1‰ to 1.5‰, for example, 1‰, 1.1‰, 1.2‰, 1.3‰, 1.4‰, 1.5‰, etc.

[0077] As a preferred embodiment, the glass transition temperature Tg of the low dielectric bismaleimide resin is 250-350°C, for example, it can be 250°C, 260°C, 270°C, 280°C, 290°C, 300°C, 310°C, 320°C, 330°C, 340°C, 350°C, etc.

[0078] As a more preferred embodiment, the low dielectric bismaleimide resin includes the following compound B1 or compound B2:

[0079]

[0080] As a preferred embodiment, the polycyclic aromatic compound containing unsaturated carbon-carbon double bonds includes any one or a combination of at least two of the compounds shown in the following formula II:

[0081]

[0082] Wherein, Y is selected from any one of the following groups:

[0083]

[0084] As a preferred embodiment, the polycyclic aromatic compound containing unsaturated carbon-carbon double bonds includes 9,9-bis(4-vinylbenzyl)-9H-fluorene and / or 2,8-bis(4-vinylbenzyl)chrysanthene.

[0085] Wherein, the structural formula of the 9,9-bis(4-vinylbenzyl)-9H-fluorene is:

[0086]

[0087] Wherein, the structural formula of the 2,8-bis(4-vinylbenzyl)chrysanthene is:

[0088]

[0089] As an optional embodiment, the flame retardant includes a phosphorus-containing flame retardant.

[0090] As a preferred embodiment, the phosphorus-containing flame retardant includes any one or a combination of at least two of the phosphorus-containing flame retardants shown in the following formula III:

[0091]

[0092] As an optional embodiment, R is selected from a C1 to C6 straight or branched alkyl group, for example, it can be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, sec-pentyl, n-hexyl, isohexyl, neohexyl, tert-hexyl, 2-methylpentyl, 3-methylpentyl.

[0093] As a more preferred embodiment, the phosphorus-containing flame retardant includes 1,4-bis(diphenylphosphino)butane.

[0094] As an optional embodiment, the filling material includes synthetic silica and / or spherical silica.

[0095] As a preferred embodiment, the filling material is spherical silica, the main function of which is to increase the bonding force.

[0096] As a preferred embodiment, the particle size of the filler material is 0.1 to 10 μm, for example, 0.1 μm, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, etc.

[0097] As a preferred embodiment, the purity of the filling material is 99.5% or higher, for example, 99.5%, 99.6%, 99.7%, 99.8%, 99.9%, etc.

[0098] As an optional embodiment, the toughening agent includes any one or a combination of at least two of polybutadiene, styrene-butadiene block copolymer, styrene-butadiene-styrene triblock copolymer, hydrogenated styrene-butadiene-styrene block copolymer or maleic anhydride grafted styrene butadiene-styrene block copolymer elastomer.

[0099] As an optional embodiment, the cross-linking agent includes any one of pentaerythritol tetraacrylate, tricyclodecane dimethanol diacrylate or triallyl isocyanurate resin, or a combination of at least two thereof.

[0100] As an optional embodiment, the initiator includes any one of azobisisobutyronitrile, azobis(2-isopropyl)butyronitrile, azobisadiponitrile, dibenzoyl peroxide, dimethylbenzoyl peroxide, diisopropyl peroxide, dicumyl peroxide, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicyclohexyl peroxide, benzoic acid peroxide, tert-butyl peroxide, butylbenzoic acid peroxide or tert-butylbenzoic acid peroxide, or a combination of at least two thereof.

[0101] As an optional embodiment, the low dielectric resin composition further includes 80 to 160 parts of a solvent, for example, 80 parts, 90 parts, 100 parts, 110 parts, 120 parts, 130 parts, 140 parts, 150 parts, 160 parts, etc.

[0102] As an optional embodiment, the solvent includes any one of toluene, butanone, acetone, dimethylformamide, methyl ethyl ketone or propylene glycol methyl ether, or a combination of at least two thereof.

[0103] In a second aspect, the present invention provides a method for preparing the low dielectric resin composition according to the first aspect, the preparation method comprising:

[0104] The low dielectric bismaleimide resin, a polycyclic aromatic compound containing unsaturated carbon-carbon double bonds, a flame retardant, a filling material, a toughening agent, a crosslinking agent and an initiator are mixed to obtain the low dielectric resin composition.

[0105] As an optional embodiment, the mixing method includes: dissolving a low-dielectric bismaleimide resin, a polycyclic aromatic compound containing unsaturated carbon-carbon double bonds, a flame retardant, a filler, a toughening agent, a crosslinking agent and an initiator in a solvent to obtain the low-dielectric resin composition.

[0106] In a third aspect, the present invention provides a metal-clad laminate comprising a prepreg and a metal foil; the prepreg comprises glass fiber cloth and a low-dielectric resin; wherein the low-dielectric resin is formed by curing the low-dielectric resin composition described in the first aspect.

[0107] As an optional embodiment, the glass fiber cloth may be of L2 grade, with specifications including but not limited to 1035, 1078, 1080 or 2116.

[0108] As an optional embodiment, the metal foil includes 1 / 3oz, Hoz, 1oz, 2oz, 3oz, 4oz or RTF metal foil.

[0109] As an optional embodiment, the metal clad laminate may have various sizes, including but not limited to 36×48, 37×49, 40×48, 40.5×48.5, 41×49, 42.5×48.5 or 43×49.

[0110] In a fourth aspect, the present invention provides a method for preparing the metal-clad laminate, the method comprising:

[0111] Applying the low dielectric resin composition on the glass fiber cloth and semi-curing it to obtain the prepreg;

[0112] The prepreg and the metal foil are stacked and pressed to obtain the metal-clad laminate.

[0113] As an optional embodiment, the coating amount of the low dielectric resin composition is 140 to 180 g / m 2 , for example, it can be 140g / m 2 , 145g / m 2 , 150g / m 2 , 155g / m 2 , 160g / m 2 , 165g / m 2 , 170g / m 2 , 175g / m 2 , 180g / m 2 wait.

[0114] As an optional embodiment, the coating line speed is 8 to 25 m / min, for example, it can be 8 m / min, 9 m / min, 10 m / min, 11 m / min, 12 m / min, 13 m / min, 14 m / min, 15 m / min, 16 m / min, 17 m / min, 18 m / min, 19 m / min, 20 m / min, 21 m / min, 22 m / min, 23 m / min, 24 m / min, 25 m / min, etc.

[0115] As an optional embodiment, the semi-curing temperature is 110-230°C, for example, it can be 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, etc.

[0116] As an optional embodiment, the semi-curing time is 3 to 6 minutes, for example, it can be 3 minutes, 3.5 minutes, 4 minutes, 4.5 minutes, 5 minutes, 5.5 minutes, 6 minutes, etc.

[0117] As an optional embodiment, the pressing pressure is 70-600 psi, for example, it can be 70 psi, 100 psi, 150 psi, 200 psi, 250 psi, 300 psi, 350 psi, 400 psi, 450 psi, 500 psi, 550 psi, 600 psi, etc.

[0118] As an optional embodiment, the pressing temperature is 70-240°C, for example, it can be 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, etc.

[0119] As an optional embodiment, the vacuum degree of the pressing is 0.02-0.1 MPa, for example, it can be 0.02 MPa, 0.03 MPa, 0.04 MPa, 0.05 MPa, 0.06 MPa, 0.07 MPa, 0.08 MPa, 0.09 MPa, 0.1 MPa, etc.

[0120] As an optional embodiment, the pressing time is 50 to 200 min, for example, it can be 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min, 120 min, 130 min, 140 min, 150 min, 160 min, 170 min, 180 min, 190 min, 200 min, etc.

[0121] It should be noted that, in the present invention, solidification is completed simultaneously during the pressing process.

[0122] In a fifth aspect, the present invention provides a use of the low dielectric resin composition as described in the first aspect, or the metal-clad laminate as described in the third aspect, in the preparation of a high-frequency and high-speed printed circuit board.

[0123] In a sixth aspect, the present invention provides a high-frequency and high-speed printed circuit board, comprising the low-dielectric resin composition as described in the first aspect, or the metal-clad laminate as described in the third aspect.

[0124] The present invention is further described below by means of specific examples and comparative examples. However, it should be understood that these examples are merely provided for more detailed description and are not to be construed as limiting the present invention in any form.

[0125] Preparation Example 1

[0126] This preparation example provides a bismaleimide resin, which is the following compound B1:

[0127]

[0128] The compound B1 described in this preparation example was prepared by the following steps:

[0129] (1) Preparation of bisphenol fluorene intermediate (intermediate):

[0130] 9,9-bis(4-hydroxyphenyl)fluorene (15.0 g, 0.036 mol) and 2,6-dimethyl-4-chloromethylphenol (18.2 g, 0.088 mol) were dissolved in N,N-dimethylformamide (DMF, 100 mL), and anhydrous potassium carbonate (24.8 g, 0.18 mol) was added. Under nitrogen, the temperature was raised to 100°C and the reaction was allowed to proceed for 12 hours. After completion of the reaction, the mixture was cooled to room temperature, filtered to remove salt, and the filtrate was neutralized with dilute hydrochloric acid (5% v / v) to pH 7, resulting in the precipitation of a white solid. The solid was then filtered and recrystallized from ethanol to obtain Intermediate A (22.5 g, 78% yield).

[0131] (2) Preparation of compound B1:

[0132] Intermediate A (10.0 g, 0.012 mol) synthesized in step (1) and maleic anhydride (4.8 g, 0.049 mol) were dissolved in acetic anhydride (50 mL), and p-toluenesulfonic acid (0.5 g) was added as a catalyst. Under nitrogen protection, the temperature was raised to 120°C and the reaction was carried out for 8 hours. After cooling, the reaction solution was poured into ice water to precipitate a yellow precipitate. The precipitate was filtered, washed with cold ethanol and deionized water in sequence, and dried in vacuo to obtain the target resin compound B1 (12.1 g, yield 85%) as a light yellow powder.

[0133] Preparation Example 2

[0134] This preparation example provides a bismaleimide resin, which is the following compound B2:

[0135]

[0136] The compound B2 described in this preparation example was prepared by the following steps:

[0137] (1) Preparation of bisphenol tetraphenylmethylene intermediate C:

[0138] 4,4'-Benzhydryl bisphenol (10.0 g, 0.042 mol), 2,6-dimethyl-4-chloromethylphenol (20.5 g, 0.10 mol) and anhydrous potassium carbonate (27.6 g, 0.20 mol) were dissolved in N-methylpyrrolidone (NMP, 150 mL); under nitrogen protection, the temperature was raised to 110°C and the reaction was carried out for 15 hours; after the reaction was completed, the reaction was cooled to room temperature and filtered to remove salt. The filtrate was neutralized with dilute hydrochloric acid (5% v / v) to pH = 7, and a white precipitate was precipitated. The precipitate was filtered and recrystallized with methanol / water (3:1) to obtain intermediate C (18.7 g, yield 75%).

[0139] (2) Preparation of compound B2:

[0140] Intermediate C (12.0 g, 0.015 mol) and maleic anhydride (6.2 g, 0.063 mol) were dissolved in acetic anhydride (60 mL), and p-toluenesulfonic acid (0.6 g) was added as a catalyst. Under nitrogen protection, the temperature was raised to 130°C and the reaction was carried out for 10 h. After cooling, the reaction solution was poured into ice water to precipitate a yellow precipitate. The precipitate was filtered, washed with cold ethanol and deionized water in sequence, and dried in vacuo to obtain the target resin as a light yellow powder (14.3 g, yield 82%).

[0141] The sources of the components in the following examples and comparative examples are as follows:

[0142]

[0143]

[0144] Examples 1 to 6

[0145] Examples 1 to 6 provide six low dielectric resin compositions and metal-clad laminates prepared therefrom; wherein the low dielectric resin compositions comprise the following components in parts by weight, as shown in Table 1 below:

[0146] Table 1

[0147]

[0148]

[0149] The metal-clad laminates provided in Examples 1 to 6 are prepared by the following steps:

[0150] (1) Weighing each solid component of the low dielectric resin composition according to the above formula and dissolving it in 100 parts of toluene to obtain the low dielectric resin composition as an adhesive;

[0151] (2) The adhesive obtained in step (1) is recycled to the glue coating machine, and after pre-soaking and main soaking, the adhesive is evenly coated (the coating amount is 5.6g / m 2 ) on the glass fiber cloth, wherein the line speed of the gluing machine is controlled at 15m / min; the glass fiber cloth coated with the adhesive is baked in a drying oven at 140°C for 6 minutes to volatilize the solvent and initially react and solidify the adhesive to obtain a prepreg;

[0152] (3) Cut the semi-cured sheets into the same size, 6 sheets in a group, and then overlap with the metal foil and press. The pressing parameters are as follows (the range value indicates that it can be achieved within this range with equivalent effect): pressure of 70-600 psi; temperature of 70-240 ° C; vacuum of 0.02-0.1 MPa; pressing time of 150 min.

[0153] Comparative Example 1

[0154] This comparative example provides a resin composition and a metal-clad laminate prepared therefrom. The only difference from Example 1 is that the bismaleimide resin B1 is replaced with 80 parts by weight of the bismaleimide resin BMI70, and the other settings are exactly the same as those in Example 1.

[0155] Comparative Example 2

[0156] This comparative example provides a resin composition and a metal-clad laminate prepared therefrom. The only difference from Example 1 is that 9,9-bis(4-vinylbenzyl)-9H-fluorene is replaced with 80 parts by weight of P,P'-divinyl-1,2-diphenylethane. Other settings are exactly the same as those in Example 1.

[0157] Comparative Example 3

[0158] This comparative example provides a resin composition and a metal-clad laminate prepared therefrom, which differs from Example 4 only in that 1,4-bis(diphenylphosphino)butane is replaced with an equal mass of decabromodiphenylethane, and other settings are exactly the same as Example 4.

[0159] Comparative Example 4

[0160] This comparative example provides a resin composition and a metal-clad laminate prepared therefrom. The only difference from Example 1 is that low-dielectric bismaleimide resin B1 is no longer added, the content of 9,9-bis(4-vinylbenzyl)-9H-fluorene is increased to 160 parts, and the other settings are exactly the same as Example 1.

[0161] Comparative Example 5

[0162] This comparative example provides a resin composition and a metal-clad laminate prepared therefrom. The only difference from Example 1 is that 9,9-bis(4-vinylbenzyl)-9H-fluorene is no longer added, the content of low-dielectric bismaleimide resin B1 is increased to 160 parts, and the other settings are exactly the same as Example 1.

[0163] Comparative Example 6

[0164] This comparative example provides a resin composition and a metal-clad laminate prepared therefrom. The only difference from Example 1 is that the content of bismaleimide resin B1 is reduced to 40 parts, and the content of 9,9-bis(4-vinylbenzyl)-9H-fluorene is increased to 120 parts. Other settings are exactly the same as Example 1.

[0165] Comparative Example 7

[0166] This comparative example provides a resin composition and a metal-clad laminate prepared therefrom. The only difference from Example 1 is that the content of bismaleimide resin B1 is increased to 120 parts, and the content of 9,9-bis(4-vinylbenzyl)-9H-fluorene is reduced to 40 parts. Other settings are exactly the same as Example 1.

[0167] Test Example 1

[0168] Test samples: the resin compositions provided in Examples 1 to 6 and the metal-clad laminates prepared therefrom, and the resin compositions provided in Comparative Examples 1 to 7 and the metal-clad laminates prepared therefrom.

[0169] Test method:

[0170] (1) Thermal stress tinning time test: Use a 50×50mm double-sided metal sample and immerse it in a 288℃ tin furnace. Record the time it takes for the sample surface to delaminate and bubble.

[0171] (2) 288°C heat resistance test (T288): An 8 mm × 8 mm metal foil substrate was placed on a thermomechanical analyzer (TMA). The temperature was raised from room temperature to 288°C at a heating rate of 10°C / min and then maintained at 288°C. The dimensional changes of the sample were observed and the time to plate burst after 288°C was recorded.

[0172] (3) Thermal expansion coefficient: The thermal expansion coefficient of the sample shall be measured using a TMA instrument in accordance with the standards specified in IPC-TM-650 2.4.24;

[0173] (4) Dielectric constant (Dk) and dielectric dissipation factor (Df): The test methods for dielectric constant and dielectric dissipation factor shall be in accordance with the test specified in IPC-TM-650 2.5.5.9;

[0174] (V) Cracking temperature (Td): Select a square sample with a size of 6.35 mm × 6.35 mm and a minimum sample weight of 30 mg. Bake at 110±2°C for 24 hours and cool to room temperature in a desiccator. Using a thermogravimetric analyzer (TGA), increase the temperature from room temperature to 450°C at a rate of 10°C / min. Record the percentage of weight loss of the sample as the temperature rises. Report the temperature at which the weight loss is 5% as Td.

[0175] (VI) Flame retardancy: Five specimens measuring 130 mm x 12.5 mm were subjected to two combustion tests in accordance with the UL94 standard. The flame retardancy was evaluated by the total duration of combustion during the combustion test.

[0176] The specific test results are shown in Table 2 below:

[0177] Table 2

[0178]

[0179]

[0180] As shown in Table 2, the samples provided in Examples 1 to 6 have a Tg value of 230°C or higher, thermal stress > 15, Dk (dielectric constant) of 3.1 or lower, Df (dielectric loss) of 0.0015 or lower, a thermal expansion coefficient Z-CTE of 1.86 to 1.97, an X / Y-CTE of 8 / 9 to 10 / 11, a UL flame retardant rating of V-0, a TD5% thermal decomposition temperature of 370°C or higher, and are qualified in the PCT test at 2atm*3hr tin immersion for 10s*3 times. This fully demonstrates that the present invention introduces a multifunctional bismaleimide resin and a polycyclic aromatic compound containing an unsaturated double bond into the low dielectric resin composition, thereby significantly improving the overall performance of the composite material, especially heat resistance and dielectric properties, having a high glass transition temperature (Tg) and thermal decomposition temperature, and being able to maintain good physical and mechanical properties in a high temperature environment.

[0181] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low dielectric resin composition, characterized in that The low dielectric resin composition comprises the following components in parts by weight:

2. The low dielectric resin composition according to claim 1, characterized in that The low dielectric bismaleimide resin includes any one or a combination of at least two of the bismaleimide resins shown in the following formula I: Wherein, X is selected from any one of the following groups: Wherein, R1 to R9 are each independently selected from any one of H, a halogen atom, a methyl group or an ethyl group; Wherein, m is 1 to 20, n is 1 to 20; Preferably, the number average molecular weight of the low dielectric bismaleimide resin is 500 to 12000, preferably 700 to 5000; Preferably, the dielectric constant Dk of the low-dielectric bismaleimide resin is 3.5 to 4.0; the dielectric loss Df of the low-dielectric bismaleimide resin is 1‰ to 1.5‰; Preferably, the glass transition temperature Tg of the low dielectric bismaleimide resin is 250-350°C.

3. The low dielectric resin composition according to claim 1, characterized in that The polycyclic aromatic compound containing unsaturated carbon-carbon double bonds includes any one or a combination of at least two of the compounds shown in the following formula II: Wherein, Y is selected from any one of the following groups: Preferably, the polycyclic aromatic compound containing unsaturated carbon-carbon double bonds includes 9,9-bis(4-vinylbenzyl)-9H-fluorene and / or 2,8-bis(4-vinylbenzyl)chrysanthene.

4. The low dielectric resin composition according to claim 1, characterized in that The flame retardant includes a phosphorus-containing flame retardant, and the phosphorus-containing flame retardant includes any one or a combination of at least two of the phosphorus-containing flame retardants shown in the following formula III: Wherein, R is selected from C1 to C6 linear or branched alkyl; Preferably, the phosphorus-containing flame retardant includes 1,4-bis(diphenylphosphino)butane.

5. The low dielectric resin composition according to claim 1, characterized in that The filling material comprises synthetic silica and / or spherical silica, preferably spherical silica; Preferably, the particle size of the filler material is 0.1 to 10 μm; Preferably, the purity of the filling material is above 99.5%; Preferably, the toughening agent comprises any one or a combination of at least two of polybutadiene, styrene-butadiene block copolymer, styrene-butadiene-styrene triblock copolymer, hydrogenated styrene-butadiene-styrene block copolymer or maleic anhydride grafted styrene-butadiene-styrene block copolymer elastomer; Preferably, the crosslinking agent comprises any one or a combination of at least two of pentaerythritol tetraacrylate, tricyclodecane dimethanol diacrylate or triallyl isocyanurate resin; Preferably, the initiator comprises any one or a combination of at least two of azobisisobutyronitrile, azobis(2-isopropyl)butyronitrile, azobisadiponitrile, dibenzoyl peroxide, dimethylbenzoyl peroxide, diisopropyl peroxide, dicumyl peroxide, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicyclohexyl peroxide, benzoic acid peroxide, tert-butyl peroxide, butylbenzoic acid peroxide or tert-butylbenzoic acid peroxide; Preferably, the low dielectric resin composition further comprises 80 to 160 parts of a solvent; Preferably, the solvent includes any one of toluene, butanone, acetone, dimethylformamide, methyl ethyl ketone or propylene glycol methyl ether, or a combination of at least two thereof.

6. A method for preparing a low dielectric resin composition according to any one of claims 1 to 5, characterized in that: The preparation method comprises: Mixing a low-dielectric bismaleimide resin, a polycyclic aromatic compound containing unsaturated carbon-carbon double bonds, a flame retardant, a filler, a toughening agent, a crosslinking agent, and an initiator to obtain the low-dielectric resin composition; Preferably, the mixing method includes: dissolving a low-dielectric bismaleimide resin, a polycyclic aromatic compound containing unsaturated carbon-carbon double bonds, a flame retardant, a filler, a toughening agent, a crosslinking agent and an initiator in a solvent to obtain the low-dielectric resin composition.

7. A metal-clad laminate, characterized in that: The metal-clad laminate comprises a prepreg and a metal foil; the prepreg comprises a glass fiber cloth and a low-dielectric resin; wherein the low-dielectric resin is formed by curing the low-dielectric resin composition according to any one of claims 1 to 5.

8. A method for preparing a metal-clad laminate according to claim 7, characterized in that: The preparation method comprises: Applying the low dielectric resin composition on the glass fiber cloth and semi-curing it to obtain the prepreg; Laminating and pressing the prepreg and the metal foil to obtain the metal-clad laminate; Preferably, the coating amount of the low dielectric resin composition is 140 to 180 g / m 2 ; Preferably, the coating line speed is 8 to 25 m / min; Preferably, the semi-curing temperature is 110-230°C, and the semi-curing time is 3-6 minutes; Preferably, the pressing pressure is 70-600 psi, the pressing temperature is 70-240° C., the pressing vacuum is 0.02-0.1 MPa, and the pressing time is 50-200 min.

9. Use of the low dielectric resin composition according to any one of claims 1 to 5 or the metal-clad laminate according to claim 7 in the preparation of a high-frequency and high-speed printed circuit board.

10. A high-frequency and high-speed printed circuit board, characterized in that: The high-frequency and high-speed printed wiring board comprises the low-dielectric resin composition according to any one of claims 1 to 5, or the metal-clad laminate according to claim 7.

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