Phosphorus-containing compound, flame and heat resistant composition, prepreg, and metal foil laminate

Abstract

The present invention provides a phosphorus-containing compound having the following formula (I): wherein R1, R2, R3, R4, R17, R18, R19, and R20 are as defined in the specification. The phosphorus-containing compound can improve the heat resistance and flame resistance of an application target, and is thus particularly suitable for the technical field of printed circuit boards.

Description

Technical Field

[0001] This invention relates to a phosphorus-containing compound that improves heat resistance and flame retardancy, and is particularly suitable for use in the field of printed circuit boards. Therefore, this invention also relates to a flame-retardant and heat-resistant composition, a prepreg, and a metal foil laminate using this phosphorus-containing compound. Background Technology

[0002] Printed circuit boards (PCBs) are the circuit boards of electronic devices, housing and electrically connecting other electronic components to provide a stable operating environment. PCBs are generally made using copper clad laminates (CCLs). CCLs are primarily composed of resin, reinforcing materials, and copper foil. Common resins include epoxy resin, phenolic resin, polyphenylene ether resin, polyurethane, silicone, and polytetrafluoroethylene (PTFE). Common reinforcing materials include fiberglass cloth, fiberglass mat, and insulating paper.

[0003] Generally, printed circuit boards (PCBs) can be manufactured as follows: A reinforcing material is impregnated in a resin composition, and then the resin-impregnated reinforcing material is cured to a semi-cured state (i.e., B-stage) to obtain a semi-cured sheet. Subsequently, the semi-cured sheets are stacked, and a metal foil is stacked on the outer side to provide a laminate. This laminate is then subjected to a hot-pressing operation (i.e., C-stage) to obtain a metal foil laminate. The metal foil on the surface of the metal foil laminate is etched to form a specific circuit pattern. Holes are then drilled in the metal foil laminate, and conductive material is plated into the holes to form vias, thus completing the fabrication of the PCB.

[0004] When manufacturing printed circuit boards using resin compositions, various flame retardants are typically added to impart flame retardancy to electronic materials. These flame retardants include halogenated or phosphorus-containing flame retardants. However, the use of halogenated flame retardants has been restricted due to environmental concerns. Commonly used phosphorus-containing flame retardants include phosphazene compounds (such as SPB-100 produced by Otsuka Chemicals) or condensed phosphate esters (such as PX-200 produced by Daihachi Chemicals). However, the heat resistance and flame retardancy of electronic materials imparted by existing phosphorus-containing flame retardants still need improvement. Summary of the Invention

[0005] In view of the above-mentioned technical problems, the present invention provides a phosphorus-containing compound that is applicable to fields requiring improved heat resistance and flame retardancy. For example, the phosphorus-containing compound is particularly suitable for addition to the dielectric layer material of printed circuit boards to improve heat resistance and flame retardancy.

[0006] Therefore, one object of the present invention is to provide a phosphorus-containing compound having the structure of the following formula (I):

[0007] Formula (I)

[0008] in,

[0009] R1, R2, R3, and R4 are each independently selected from hydrogen atoms, C1 to C6 alkyl groups, C1 to C6 alkoxy groups, and C3 to C6 cycloalkyl groups, and each R1, each R2, each R3, and each R4 may be the same or different;

[0010] R19 and R20 are each independently selected from... , , , ,and ;

[0011] R17 and R18 are each independently selected from hydrogen atoms. , , , , , , , and ;

[0012] R 6 R 7 R 9 and R a Each is independently selected from C1 to C6 hydrocarbon groups, C1 to C6 alkoxy groups, and C3 to C6 cycloalkyl groups, and when two or more R groups are present... 6 R 7 R 9 、or R a At that time, each R 6 Each R 7 Each R 9 、or each R a They can be the same or different;

[0013] R 8 Selected from -CH2-, -C(CH3)2-, -CO-, -SO2-, and -O-;

[0014] m and ma are independent integers from 0 to 4, n is an integer from 0 to 3, p is 0 or 1, and the sum of m and n does not exceed 4; and

[0015] This indicates the location of the bond.

[0016] In one embodiment of the present invention, R19 and R20 in formula (I) are each independently... or Furthermore, R17 and R18 are each independent. , , , , or Where p is 0 and R 6 R 8 R a , m, and ma are as defined in the preceding paragraph. More specifically, R17 and R18 are each independent of each other. or And R a And ma as defined in the previous paragraph.

[0017] Another object of the present invention is to provide a flame-retardant and heat-resistant composition comprising:

[0018] The first reactive component is selected from the group consisting of: epoxy resins, phenolic resins, benzoxazine resins, polyphenylene ether resins having olefinic carbon-carbon double bonds, allyl compounds, maleimide compounds, copolymers of allyl compounds and maleimide compounds, and combinations thereof; and

[0019] Phosphorus-containing compounds as described above.

[0020] In one embodiment of the invention, the polyphenylene ether resin having olefinic carbon-carbon unsaturated double bonds is selected from the group consisting of: dihydroxy polyphenylene ether resins, methacrylic polyphenylene ether resins, vinyl polyphenylene ether resins, and combinations thereof.

[0021] In one embodiment of the present invention, the allyl-containing compound is selected from the group consisting of diallyl bisphenol A, diallyl bisphenol F, diallyl bisphenol S, and combinations thereof.

[0022] In one embodiment of the invention, the maleimide compound is selected from the group consisting of bismaleimide compounds, trimaleimide compounds, tetramaleimide compounds, and combinations thereof.

[0023] Another object of the present invention is to provide a prepreg obtained by impregnating or coating a substrate with the flame-retardant and heat-resistant composition as described above, and drying the impregnated or coated substrate.

[0024] Another object of the present invention is to provide a metal foil laminate, which is made by laminating a prepreg as described above with a metal foil, or by coating a metal foil with a flame-retardant and heat-resistant composition as described above and drying the coated metal foil.

[0025] To make the above-mentioned objectives, technical features and advantages of the present invention more apparent and understandable, the following detailed description is provided with reference to some specific embodiments. Detailed Implementation

[0026] The following describes some specific embodiments of the present invention; however, the present invention can be practiced in many different forms and the scope of protection of the present invention should not be limited to the specific embodiments described.

[0027] Unless otherwise stated, the terms “a,” “the,” and similar terms used in this specification and claims shall be understood to include both singular and plural forms.

[0028] Unless otherwise stated, the weight of the solvent is not included when describing the proportions of components contained in a solution, mixture, or composition in this specification and claims.

[0029] Unless otherwise stated, the numerical ranges (e.g., 5 to 100) used in this specification and claims should be understood to include all rational numbers in that range and the range of any rational numbers in that range. Therefore, the numerical ranges used in this specification include all possible combinations of values ​​between the listed minimum and maximum values.

[0030] The advantage of this invention over the prior art is that it provides a phosphorus-containing compound that can improve the heat resistance and flame retardancy of the applied object, and is therefore particularly suitable for addition to the dielectric layer material of printed circuit boards.

[0031] 1. Phosphorus-containing compounds

[0032] The phosphorus-containing compound of the present invention has the structure of formula (I):

[0033] Formula (I).

[0034] In formula (I), R1, R2, R3, and R4 are each independently selected from hydrogen atoms, C1 to C6 alkyl groups, C1 to C6 alkoxy groups, and C3 to C6 cycloalkyl groups, and each R1, each R2, each R3, and each R4 may be the same or different. Examples of the C1 to C6 alkyl groups include, but are not limited to, substituted or unsubstituted methyl, ethyl, propyl, butyl, pentyl, and hexyl groups, wherein the alkyl group may be straight-chain or branched. Examples of the C1 to C6 alkoxy groups include, but are not limited to, substituted or unsubstituted methoxy, ethoxy, propoxy, butoxy, pentoxy, and hexoxy groups, wherein the alkoxy group may be straight-chain or branched. Examples of the C3 to C6 cycloalkyl groups include, but are not limited to, substituted or unsubstituted cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups.

[0035] In equation (I), R19 and R20 are each independently selected from... , , , ,and ,in Represents the location of the bond. R6 R 7 and R 9 Each is independently selected from C1 to C6 hydrocarbon groups, C1 to C6 alkoxy groups, and C3 to C6 cycloalkyl groups, and when two or more R groups are present... 6 R 7 、or R 9 At that time, each R 6 Each R 7 、or each R 9 They may be the same or different. The C1 to C6 hydrocarbon groups may be straight-chain or branched hydrocarbon groups, examples of which include, but are not limited to, substituted or unsubstituted methyl, ethyl, propyl, butyl, pentyl, and hexyl. Examples of the C1 to C6 alkoxy groups and C3 to C6 cycloalkyl groups are those listed above for R1, R2, R3, and R4. 8 Selected from -CH2-, -C(CH3)2-, -CO-, -SO2-, and -O-. m is an integer from 0 to 4, n is an integer from 0 to 3, p is 0 or 1, and the sum of m and n does not exceed 4.

[0036] In equation (I), R17 and R18 are each independently selected from hydrogen atoms, , , , , , , , and ,in Represents the location of the bond. R a Each is independently selected from C1 to C6 hydrocarbon groups, C1 to C6 alkoxy groups, and C3 to C6 cycloalkyl groups, and when two or more R groups are present... a At that time, each R a They may be the same or different. Examples of the C1 to C6 hydrocarbon groups are listed above for R19 and R20, and examples of the C1 to C6 alkoxy groups and C3 to C6 cycloalkyl groups are listed above for R1, R2, R3, and R4. ma is an integer from 0 to 4.

[0037] In one embodiment of the present invention, R19 and R20 in formula (I) are each independently... or Furthermore, R17 and R18 are each independent. , , , , or More specifically, R17 and R18 are each independent. or Where p is 0 and R 6 R 8R a m and ma are as defined above.

[0038] 2. Flame-retardant and heat-resistant composition

[0039] The phosphorus-containing compound of the present invention can improve the heat resistance and flame retardancy of the application object. Therefore, the present invention also provides a flame-retardant and heat-resistant composition comprising a first reactive component and the phosphorus-containing compound described above as essential components, as well as other optional components as needed.

[0040] 2.1. First reactive component

[0041] The first reactive component comprises one or more selected from epoxy resins, phenolic resins, benzoxazine resins, polyphenylene ether resins having olefinic carbon-carbon unsaturated double bonds, allyl compounds, maleimide compounds, and copolymers containing allyl compounds and maleimide compounds. In this document, epoxy resin refers to a thermosetting resin having at least two epoxy functional groups in one molecule, such as difunctional epoxy resins, tetrafunctional epoxy resins, octafunctional epoxy resins, or linear phenolic epoxy resins, and there is no particular limitation on its type. Phenolic resin refers to a resin obtained by the condensation of phenolic compounds and aldehyde compounds, examples of which include, but are not limited to, phenol-formaldehyde resins, cresol-formaldehyde resins, and resorcinol-formaldehyde resins. Examples of benzoxazine resins include, but are not limited to, phenolic benzoxazine resins and bisphenol A benzoxazine resins.

[0042] Examples of the polyphenylene ether resin having olefin-type carbon-carbon unsaturated double bonds include, but are not limited to, dihydroxy polyphenylene ether resins (e.g., SABIC's SA90 product), methacrylate polyphenylene ether resins (e.g., SABIC's SA9000 product), and vinyl polyphenylene ether resins (e.g., Mitsubishi Gas Chemical's OPE2ST product), and each of these polyphenylene ether resins having olefin-type carbon-carbon unsaturated double bonds can be used alone or in any combination.

[0043] The allyl-containing compound is a polyfunctional allyl-containing compound, preferably selected from the group consisting of diallyl bisphenol A, diallyl bisphenol F, diallyl bisphenol S, and combinations thereof.

[0044] The maleimide compound is preferably a multifunctional maleimide compound, such as a bismaleimide compound, a trimaleimide compound, or a tetramaleimide compound, and more preferably a bismaleimide compound. Specifically, the maleimide compound may be selected from the group consisting of: 1,2-bismaleimide ethane, 1,6-bismaleimide hexane, 1,3-bismaleimide benzene, 1,4-bismaleimide benzene, 2,4-bismaleimide toluene, 4,4'-bismaleimide diphenylmethane, 4,4'-bismaleimide diphenyl ether, 3,3'-bismaleimide diphenyl sulfone, 4,4 ... Maleimide dicyclohexylmethane, 3,5-bis(4-maleimide phenyl)pyridine, 2,6-bismaleimide pyridine, 1,3-bis(maleimide methyl)cyclohexane, 1,3-bis(maleimide methyl)benzene, 1,1-bis(4-maleimide phenyl)cyclohexane, 1,3-bis(dichloromaleimide)benzene, 4,4'-biscitraconimidodiphenylmethane (4,4'-biscitraconimidodiphenylmethane) lmethane), 2,2-bis(4-maleimide-phenyl)propane, 1-phenyl-1,1-bis(4-maleimide-phenyl)ethane, α,α-bis(4-maleimide-phenyl)toluene, 3,5-bismaleimide-1,2,4-triazole, N,N'-epenylethylbismaleimide, N,N'-hexamethylenebismaleimide, N,N'-m-epenylphenylbismaleimide, N,N'-p-epenylphenylbismaleimide, N,N'- 4,4'-Diphenylmethane bismaleimide, N,N'-4,4'-diphenyl ether bismaleimide, N,N'-4,4'-diphenyl sulfone bismaleimide, N,N'-4,4'-dicyclohexylmethane bismaleimide, N,N'-α,α'-4,4'-dimethylenecyclohexane bismaleimide, N,N'-m-xylene bismaleimide, N,N'-4,4'-diphenylcyclohexane bismaleimide, benzyl maleimide oligomers, and combinations thereof.

[0045] 2.2. Phosphorus-containing compounds

[0046] The phosphorus-containing compound is the phosphorus-containing compound of the present invention as described above. The content of the phosphorus-containing compound in the flame-retardant and heat-resistant composition can be adjusted as needed. Generally, the content of the phosphorus-containing compound can be from 0.1% to 30% by weight, more specifically from 1% to 25% by weight, based on the total weight of the flame-retardant and heat-resistant composition excluding solvents. For example, based on the total weight of the first reactive component and the phosphorus-containing compound, the content of the phosphorus-containing compound can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, or 25% by weight, or within the range of any two of the above values, but the present invention is not limited thereto.

[0047] 2.3. Selection of Ingredients

[0048] In addition to the above-mentioned components, the flame-retardant and heat-resistant composition of the present invention may further include selected components, such as additives existing in the art, without departing from the technical principles of the present invention, to improve the physicochemical properties of the metal foil laminate made by the flame-retardant and heat-resistant composition or the processability of the flame-retardant and heat-resistant composition during the manufacturing process.

[0049] Examples of existing additives include, but are not limited to, fillers, catalysts, elastomers, dispersants, toughening agents, viscosity modifiers, plasticizers, and coupling agents. These additives can be used alone or in combination. The use of such additives is something that those skilled in the art, upon viewing the disclosure of this specification, can do as needed based on their ordinary knowledge, and is not the focus of this invention; therefore, it will not be elaborated upon here.

[0050] 3. Prepreg

[0051] This invention also provides a prepreg made from the above-described flame-retardant and heat-resistant composition, wherein the prepreg is prepared by impregnating a substrate with the flame-retardant and heat-resistant composition described above or coating a substrate with the flame-retardant and heat-resistant composition described above, and then drying the impregnated or coated substrate. The substrate can be a reinforcing material commonly used in the field of printed circuit board technology, examples of which include, but are not limited to, paper, cloth, or felt made of glass fiber. In one embodiment of this invention, 2116 glass fiber cloth is used as the substrate, and the prepreg is heated and dried at 170°C to obtain a prepreg in a semi-cured state.

[0052] 4. Metal foil laminate

[0053] The present invention also provides a metal foil laminate, which is obtained by laminating the aforementioned prepreg and metal foil. Specifically, the metal foil laminate of the present invention comprises a dielectric layer and a metal layer, wherein the dielectric layer is provided by the prepreg as described above, wherein multiple layers of prepreg serve as the dielectric layer, and a metal foil (such as copper foil, as the metal layer) is laminated on at least one outer surface of the dielectric layer to provide a laminate, and the laminate is subjected to a hot pressing operation to obtain the metal foil laminate. Alternatively, the flame-retardant and heat-resistant composition of the present invention can be directly coated onto the metal foil and the coated metal foil can be dried to obtain the metal foil laminate.

[0054] The outer metal foil of the metal foil laminate can be further patterned to form a printed circuit board. Patterning methods include, but are not limited to, etching.

[0055] 5. Examples

[0056] 5.1. Measurement Method Description

[0057] The present invention will now be further illustrated by the following specific embodiments, wherein the measuring instruments and methods used are as follows:

[0058] [UL 94 Vertical Burning Test]

[0059] Copper foil laminates were etched to remove the copper foil from both sides, resulting in copper foil-free test pieces. These pieces were fixed vertically and burned with a Bunsen burner to compare their self-extinguishing and combustion-supporting characteristics. According to the UL 94 flame retardancy test standard, a V0 rating indicates that after two 10-second flame tests, combustion ceases within 10 seconds without any burning drips; a V1 rating indicates that after two 10-second flame tests under the same conditions, combustion ceases within 30 seconds without any burning drips; and a V2 rating indicates that after two 10-second flame tests under the same conditions, combustion ceases within 30 seconds but with burning drips. Therefore, the flame retardancy ratings are ranked as follows: V0 > V1, V1 > V2. In this test, five test pieces from each group were subjected to five UL 94 flame retardancy tests, with each test using a new test piece.

[0060] [Glass Transfer Temperature (Tg) Test]

[0061] The copper foil laminate was etched to remove the copper foil from both sides, resulting in a copper foil-free specimen. The glass transition temperature (Tg) of the specimen was measured using a thermomechanical analyzer (TMA). The test conditions were as follows: heating rate of 10°C / min, from 30°C to 330°C.

[0062] 5.2 Preparation of phosphorus-containing compounds

[0063] [Preparation Example 1]

[0064] 285 g of DOPO (3,4:5,6-dibenzo-2H-1,2-oxaphosphorin-2-oxide; CAS No. 35948-25-5) and 107 g of DHBP (Bis(4-hydroxyphenyl)methanone; CAS No. 611-99-4) were added to a 1000 mL reactor. The mixture was slowly heated to 180 °C and stirred at 180 °C for 1.5 hours. Then, the temperature was lowered to 110 °C, and 1000 mL of toluene was added to the reactor. The mixture was then stirred at 110 °C for 30 minutes. The precipitate was collected by vacuum filtration and dried at 120 °C for 5 hours to obtain the intermediate product. The intermediate product was dissolved in 3000 mL of ethanol solution containing 24 g of potassium hydroxide (KOH) and stirred until completely dissolved. Then, 120 g of CMS (1-(chloromethyl)-4-vinylbenzene; CAS No. 1592-20-7) was added dropwise and stirred at room temperature for 48 hours. The precipitate was removed by vacuum filtration, and the solid was washed with water and ethanol and dried by rotary condensation to obtain a white powder containing phosphorus compound 1 with the following structure.

[0065]

[0066] [Preparation Example 2]

[0067] 85.6 g of the phosphorus-containing compound 1 prepared in Preparation Example 1, 36.4 g of BBrBCB (4-bromobenzocyclobutene; CAS No. 1073-39-8), 2.4 g of palladium(II) acetate (CAS No. 3375-31-3), 2.62 g of TPP (triphenylphosphine; CAS No. 603-35-0), 120 mL of N,N-Diethylethanamine (CAS No. 121-44-8), and 120 mL of DMF (dimethylformamide; CAS No. 68-12-2) were added to a 500 mL reactor and stirred at 100 °C for 18 hours under a nitrogen atmosphere. Next, the solution was filtered to remove palladium black, then the solution was added dropwise to 1000 ml of water, the precipitate was removed by vacuum filtration, and dried by rotary concentration to obtain a white solid containing phosphorus compound 2 with the following structure.

[0068]

[0069] [Preparation Example 3]

[0070] 285 g of DOPO (CAS No. 35948-25-5) and 107 g of DHBP (CAS No. 611-99-4) were added to a 1000 mL reactor. The temperature was slowly raised to 180 °C and stirred at 180 °C for 1.5 hours. Then, the temperature was lowered to 110 °C, and 1000 mL of toluene was added to the reactor. The mixture was then stirred at 110 °C for 30 minutes. The precipitate was collected by vacuum filtration and dried at 120 °C for 5 hours to obtain the intermediate product. 62.6 g of the intermediate product was dissolved in 200 mL of DMSO (dimethyl sulfoxide), and 17 g of sodium hydroxide (NaOH; 50 wt%) was added. The mixture was stirred until completely clear. Then, 17 g of allyl chloride (CAS No. 107-05-1) was added dropwise, and the mixture was slowly heated to 65 °C and stirred for 30 minutes. Afterward, the mixture was allowed to cool naturally to room temperature, and then 500 mL of water was added for extraction with toluene. The solid obtained after drying the toluene was directly placed in a reaction vessel and stirred at 180°C for 6 hours under a nitrogen atmosphere. Next, the mixture was cooled to room temperature, and the solid was dissolved in 3000 mL of ethanol solution containing 24 g of potassium hydroxide (KOH), stirred until completely dissolved, and then 120 g of CMS (CAS No. 1592-20-7) was added dropwise. The mixture was stirred at room temperature for 48 hours, filtered under vacuum to remove the precipitate, washed with water and ethanol, and dried by rotary condensation to obtain a yellow-brown powder containing phosphorus compound 3 with the following structure.

[0071]

[0072] 5.3 Preparation of Flame-Resistant and Heat-Resistant Compositions

[0073] [Example 1]

[0074] Take 60 grams of 2,2'-diallyl bisphenol and polyamine maleimide polymer (60% by weight solids; commercial model: UB-20, purchased from Changchun Artificial Resin) and place them in a beaker. Heat the mixture to 130°C using an electromagnetic stirrer, then add 2 grams of phosphorus-containing compound 1. Stir until the mixture is clear to obtain the flame-retardant and heat-resistant composition of Example 1 containing 5% by weight of phosphorus-containing compound 1.

[0075] [Example 2]

[0076] The flame-retardant and heat-resistant composition of Example 2 was prepared in the same manner as in Example 1, but the amount of phosphorus compound 1 was adjusted to 4 grams, thereby obtaining the flame-retardant and heat-resistant composition of Example 2 containing 10% by weight of phosphorus compound 1.

[0077] [Example 3]

[0078] The flame-retardant and heat-resistant composition of Example 3 was prepared in the same manner as in Example 1, but the amount of phosphorus compound 1 was adjusted to 6 grams, thereby obtaining the flame-retardant and heat-resistant composition of Example 3 containing 15% by weight of phosphorus compound 1.

[0079] [Example 4]

[0080] Take 57 grams of 2,2'-diallyl bisphenol and polyamine maleimide polymer (60% by weight solids; commercial model: UB-20) and place them in a beaker. Heat the mixture to 130°C using an electromagnetic stirrer. Then add 6 grams of phosphorus-containing compound 2 and stir until clear to obtain the flame-retardant and heat-resistant composition of Example 4 containing 15% by weight of phosphorus-containing compound 2.

[0081] [Example 5]

[0082] Take 57 grams of 2,2'-diallyl bisphenol and polyamine maleimide polymer (60% by weight solids; commercial model: UB-20) and place them in a beaker. Heat the mixture to 130°C using an electromagnetic stirrer, then add 6 grams of phosphorus-containing compound 3. Stir until the mixture is clear to obtain the flame-retardant and heat-resistant composition of Example 5 containing 15% by weight of phosphorus-containing compound 3.

[0083] [Comparative Example 1]

[0084] Take 80 grams of 2,2'-diallylbisphenol and polyamine maleimide polymer (60% by weight solids; commercial model: UB-20) and place them in a beaker. Heat the mixture to 130°C using an electromagnetic stirrer to obtain the flame-retardant and heat-resistant composition of Comparative Example 1.

[0085] [Comparative Example 2]

[0086] Take 57 grams of 2,2'-diallyl bisphenol and polyamine maleimide polymer (60% by weight solids; commercial model: UB-20) and place them in a beaker. Heat the mixture to 130°C using an electromagnetic stirrer. Then add 6 grams of phosphorus-containing compound PX-200 (purchased from Daihachi Chemical) with the following structural formula. Stir until clear to obtain the flame-retardant and heat-resistant composition of Comparative Example 2 containing 15% by weight of phosphorus-containing compound.

[0087] PX-200

[0088] [Comparative Example 3]

[0089] Take 60 grams of 2,2'-diallyl bisphenol and polyamine maleimide polymer (60% by weight solids; trade name: UB-20) and place them in a beaker. Heat the mixture to 130°C using an electromagnetic stirrer. Then add 4 grams of a phosphorus-containing compound Di-DOPO with the following structural formula (preparation method according to US 20120053265 A1) and stir until clear to obtain the flame-retardant and heat-resistant composition of Comparative Example 3 containing 10% by weight of the phosphorus-containing compound.

[0090] Di-DOPO

[0091] 5.4. Preparation and performance testing of metal foil laminates

[0092] The obtained flame-retardant and heat-resistant compositions were used to prepare the metal foil laminates of Examples 1 to 5 and Comparative Examples 1 to 3, respectively. First, glass fiber cloth (model: 2116) was impregnated with the flame-retardant and heat-resistant compositions of Examples 1 to 5 and Comparative Examples 1 to 3, respectively. Next, the impregnated glass fiber was placed in a dryer at 170°C and heated and dried for 3 minutes to obtain a semi-cured sheet in a semi-cured state (B-stage). Then, the semi-cured sheet was cut into test pieces with a length and width of 13 cm, and a copper foil was laminated on each side. Subsequently, it was vacuum hot-pressed at 220°C for 2 hours to obtain the metal foil laminate.

[0093] The flame retardancy and heat resistance of the metal foil laminates of Examples 1 to 5 and Comparative Examples 1 to 3 were measured according to the measurement methods described above, and the results are recorded in Table 1.

[0094] Table 1:

[0095]

[0096] The metal foil laminates of Examples 1 to 5 all achieved a V1 rating, and even a V0 rating, in five UL 94 vertical burning tests, exhibiting excellent heat resistance (high Tg). In contrast, Comparative Example 1, which did not use a flame retardant, achieved a V1 rating in flame retardancy, but its heat resistance was poor (below 180°C). Comparative Examples 2 and 3 showed that even with higher phosphorus content, good heat resistance and flame retardancy could not be simultaneously achieved when using other phosphorus-containing compounds not of the present invention. The above experimental results clearly demonstrate that the phosphorus-containing compounds of the present invention can indeed provide the effect of improving the heat resistance and flame retardancy of the application object.

[0097] The above embodiments are merely illustrative of the principles and effects of the present invention and to illustrate its technical features, and are not intended to limit the scope of protection of the present invention. Any changes or arrangements that can be easily made by those skilled in the art without departing from the technical principles of the present invention are within the scope claimed by the present invention.

Claims

1. A phosphorus-containing compound, characterized in that, It has the structure of the following formula (I): Equation (I) in, R1, R2, R3, and R4 are each independently selected from hydrogen atoms, C1 to C6 alkyl groups, C1 to C6 alkoxy groups, and C3 to C6 cycloalkyl groups, and each R1, each R2, each R3, and each R4 may be the same or different; R19 and R20 are each independently selected from... , , , ,and ; R17 and R18 are each independently selected from hydrogen atoms. , , , , , , , and ; R 6 R 7 R 9 and R a Each is independently selected from C1 to C6 hydrocarbon groups, C1 to C6 alkoxy groups, and C3 to C6 cycloalkyl groups, and when two or more R groups are present... 6 R 7 R 9 、or R a At that time, each R 6 Each R 7 Each R 9 、or each R a They can be the same or different; R 8 Each is independently selected from -CH2-, -C(CH3)2-, -CO-, -SO2-, and -O-; m and ma are independent integers from 0 to 4, n is an integer from 0 to 3, p is 0 or 1, and the sum of m and n does not exceed 4; and This indicates the location of the bond.

2. The phosphorus-containing compound according to claim 1, characterized in that, R19 and R20 are each independent or Furthermore, R17 and R18 are each independent. , , , , or Where p is 0 and R 6 R 8 R a m and ma are as defined in claim 1.

3. The phosphorus-containing compound according to claim 2, characterized in that, R17 and R18 are each independent or And R a and ma as defined in claim 1.

4. A flame-retardant and heat-resistant composition, characterized in that, Include: The first reactive component is selected from the following group: epoxy resins, phenolic resins, benzoxazine resins, polyphenylene ether resins having olefinic carbon-carbon unsaturated double bonds, allyl compounds, maleimide compounds, copolymers of allyl compounds and maleimide compounds, and combinations thereof. as well as The phosphorus-containing compound as described in any one of claims 1 to 3.

5. The flame-retardant and heat-resistant composition according to claim 4, characterized in that, The polyphenylene ether resin having olefinic carbon-carbon unsaturated double bonds is selected from the group consisting of: dihydroxy polyphenylene ether resins, methacrylic polyphenylene ether resins, vinyl polyphenylene ether resins, and combinations thereof.

6. The flame-retardant and heat-resistant composition according to claim 4, characterized in that, The allyl-containing compound is selected from the following group: diallyl bisphenol A, diallyl bisphenol F, diallyl bisphenol S, and combinations thereof.

7. The flame-retardant and heat-resistant composition according to claim 4, characterized in that, The maleimide compound is selected from the following group: bismaleimide compounds, trimaleimide compounds, tetramaleimide compounds, and combinations thereof.

8. The flame-retardant and heat-resistant composition according to any one of claims 4 to 7, characterized in that, It further comprises ingredients selected from the group consisting of fillers, catalysts, elastomers, dispersants, toughening agents, viscosity modifiers, plasticizers, coupling agents, and combinations thereof.

9. A semi-cured sheet, characterized in that, It is prepared by impregnating or coating a substrate with the flame-retardant and heat-resistant composition as described in any one of claims 4 to 8, and drying the impregnated or coated substrate.

10. A metal foil laminate, characterized in that, It is prepared by laminating the prepreg as described in claim 9 with a metal foil, or by coating the metal foil with the flame-retardant and heat-resistant composition as described in any one of claims 4 to 8 and drying the coated metal foil.

Images