Phosphorus-containing compound, preparation method thereof, resin composition and product thereof

Abstract

The invention discloses a phosphorus-containing compound with a structure as shown in a formula (I), a preparation method thereof, a resin composition and a product thereof. In formula (I), n is 0 or 1, and the Ar group represents a divalent aromatic hydrocarbon group. The phosphorus-containing compounds may be used in resin compositions to improve properties of articles, including increasing glass transition temperature, reducing Z-axis thermal expansion rate, improving T288 heat resistance, improving flame retardant migration, improving flame retardant shedding, and / or improving crosslinking gaps.

Description

Technical Field

[0001] This invention relates to a phosphorus-containing compound, and more particularly to a phosphorus-containing compound that can be used as a flame retardant, its preparation method, resin composition, and articles thereof. Background Technology

[0002] Halogenated flame retardants easily produce toxic substances during combustion, which limits their application due to environmental concerns. In contrast, phosphorus-containing flame retardants have attracted much attention due to their low toxicity and high efficiency. However, most phosphate esters are liquids with high volatility and are prone to migration and leakage. Therefore, developing a phosphate ester that is compatible with materials and does not easily leach out is an urgent problem to be solved.

[0003] On the other hand, phosphorus-containing flame retardants are used in various materials such as copper-clad laminates. While possessing flame retardancy, it is also desirable to avoid degrading the various properties of the copper-clad laminate material, such as glass transition temperature, Z-axis thermal expansion coefficient, and T288 heat resistance. Therefore, how to develop a phosphorus-containing flame retardant that does not degrade, or even improves, at least one of the aforementioned properties is a matter of great concern in the industry. Summary of the Invention

[0004] In view of the problems encountered in the prior art, especially the inability of existing materials to meet one or more property requirements, the main objective of the present invention is to provide a novel phosphorus-containing compound that, while possessing flame retardancy, also meets at least one property requirement such as glass transition temperature, Z-axis thermal expansion coefficient, and T288 heat resistance, and can avoid problems such as flame retardant migration, flame retardant shedding, or cross-linking gaps.

[0005] Another major objective of this invention is to provide a method for preparing the above-mentioned phosphorus-containing compound.

[0006] Another major object of the present invention is to provide a resin composition comprising the above-mentioned phosphorus-containing compound, and articles made from the aforementioned resin composition, the articles comprising prepreg, resin film, laminate, printed circuit board or cured insulator.

[0007] Specifically, the present invention provides a phosphorus-containing compound having the structure shown in formula (I):

[0008]

[0009] Where n is 0 or 1, and the Ar group represents a divalent aromatic hydrocarbon group.

[0010] For example, in one embodiment, the divalent aromatic hydrocarbon group includes benzoxyl, naphthyl, or biphenylxyl.

[0011] For example, in one embodiment, the divalent aromatic hydrocarbon group may or may not be substituted.

[0012] For example, in one embodiment, the phosphorus-containing compound has the structure shown in formula (II):

[0013]

[0014] For example, in one embodiment, the phosphorus-containing compound has the structure shown in formula (III):

[0015]

[0016] For example, in one embodiment, the phosphorus content of the phosphorus-containing compound is between 9% and 15%.

[0017] On the other hand, the present invention provides a method for preparing a phosphorus-containing compound having the structure shown in formula (I), the method comprising: reacting a compound having the structure shown in formula (A) with a compound having the structure shown in formula (B) to obtain the phosphorus-containing compound having the structure shown in formula (I):

[0018]

[0019] Where X represents a hydroxyl or magnesium halide group, and Ar group represents a divalent aromatic hydrocarbon group.

[0020] For example, in one embodiment, the preparation method further includes reacting pentaerythritol with phosphorus oxychloride to prepare a compound with the structure shown in formula (A).

[0021] For example, in one embodiment, the compound with the structure shown in formula (A) and the compound with the structure shown in formula (B) react in the presence of an acid-binding agent.

[0022] For example, in one embodiment, the compound with the structure shown in formula (A) and the compound with the structure shown in formula (B) are reacted in the absence of an acid-binding agent.

[0023] For example, in one embodiment, the compound with the structure shown in formula (B) is hydroxystyrene, styrene magnesium bromide, or styrene magnesium chloride.

[0024] On the other hand, the present invention provides a resin composition comprising 100 parts by weight of maleimide resin and 10 to 80 parts by weight of a phosphorus-containing compound having the structure shown in formula (I).

[0025] For example, in one embodiment, the maleimide resin includes 4,4'-diphenylmethane bismaleimide, benzene maleimide oligomer, biphenyl aralkyl bismaleimide, indene-containing bismaleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 2,3-dimethylbenzenemaleimide, 2,6-dimethylbenzenemaleimide, N-phenylmaleimide, and resins containing C5 to C64. 50 Maleimide resins or combinations thereof with aliphatic long-chain structures.

[0026] For example, in one embodiment, the resin composition comprises 100 parts by weight of maleimide resin and 20 to 70 parts by weight of a phosphorus-containing compound having the structure shown in formula (I).

[0027] For example, in one embodiment, the resin composition further includes an amine curing agent, an inorganic filler, a curing accelerator, a polymerization inhibitor, a colorant, a solvent, a toughening agent, a silane coupling agent, or a combination thereof.

[0028] On the other hand, the present invention provides an article made from the resin composition, comprising a prepreg, a resin film, a laminate, a printed circuit board, or a cured insulator.

[0029] For example, in one embodiment, the aforementioned article has one, more, or all of the following characteristics:

[0030] The glass transition temperature measured by a dynamic mechanical analyzer according to the method described in IPC-TM-650 2.4.24.4 is greater than or equal to 245°C.

[0031] The Z-axis thermal expansion coefficient measured by a thermomechanical analyzer according to the method described in IPC-TM-650 2.4.24.5 is less than or equal to 1.45%;

[0032] The non-explosion time measured by a thermomechanical analyzer, as described in IPC-TM-650 2.4.24.1, is greater than or equal to 50 minutes.

[0033] The flame retardancy rating obtained by measuring according to the method described in UL 94 is V-0 or V-1.

[0034] Visual inspection confirmed that no flame retardant migration was found in the product;

[0035] Scanning electron microscopy confirmed that no flame retardant had detached from the product; and

[0036] Scanning electron microscopy confirmed that there were no cross-linking gaps in the product. Attached Figure Description

[0037] Figure 1 The image shows the FTIR spectrum of a phosphorus-containing compound.

[0038] Figure 2 Phosphorus-containing compounds 1 H NMR spectrum.

[0039] Figure 3 This is the LC-MS spectrum of a phosphorus-containing compound.

[0040] Figure 4 Photograph of a sample from which flame retardant has detached.

[0041] Figure 5 Photograph of a sample without flame retardant detachment.

[0042] Figure 6 and Figure 7 This is a photograph of a sample with crosslinking gaps.

[0043] Figure 8 This is a photograph of a sample without crosslinking gaps. Detailed Implementation

[0044] To enable those skilled in the art to understand the features and effects of this invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding this invention, and in case of conflict, the definitions in this specification shall prevail.

[0045] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0046] The present invention uses the terms "a," "an," "an," or similar expressions to describe the components and technical features described herein. Such descriptions are merely for convenience and to provide a general meaning regarding the scope of the invention. Therefore, such descriptions should be understood to include one or at least one, and the singular includes the plural, unless clearly otherwise indicated.

[0047] In this document, the terms “comprising,” “including,” “having,” “containing,” or any similar terms are open-ended transitional phrases intended to encompass non-exclusive inclusions. For example, a composition or article containing a plurality of elements is not limited to those listed herein, but may also include other elements not explicitly listed but typically inherent to the composition or article. Furthermore, unless explicitly stated otherwise, the term “or” is inclusive, not exclusive. For example, the condition “P or Q” is satisfied in any of the following cases: P is true (or exists) and Q is false (or does not exist); P is false (or does not exist) and Q is true (or exists); both P and Q are true (or exist). Moreover, in this document, the terms “comprising,” “including,” “having,” and “containing” are interpreted as specifically revealing and simultaneously encompassing closed conjunctions such as “composed of” and conjunctions such as “substantially composed of.”

[0048] In this article, the terms “and,” “with,” “as well as,” or other similar terms are used to connect parallel sentence components, and there is no distinction between primary and secondary components. The meaning of the parallel sentence components does not change after their positions are interchanged.

[0049] In this document, all features or conditions defined in the form of numerical ranges or percentage ranges are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as encompassing and specifically revealing all possible subranges and individual values ​​within those ranges, particularly integer values. For example, a range description of "1 to 8" should be considered as specifically revealing all subranges such as 1 to 7, 2 to 8, 2 to 6, 3 to 6, 4 to 8, 3 to 8, etc., particularly subranges defined by all integer values, and should be considered as specifically revealing individual values ​​within those ranges such as 1, 2, 3, 4, 5, 6, 7, 8, etc. Similarly, a range description of "between 1 and 8" should be considered as specifically revealing all ranges such as 1 to 8, 1 to 7, 2 to 8, 2 to 6, 3 to 6, 4 to 8, 3 to 8, etc., including endpoint values. Unless otherwise specified, the foregoing interpretation applies to all content throughout this invention, regardless of its scope.

[0050] If a quantity or other numerical value or parameter is expressed as a range, preferred range, or a series of upper and lower limits, it should be understood that this document has specifically disclosed all ranges consisting of any upper or preferred value of that range and the lower or preferred value of that range, whether such ranges are disclosed separately or not. Furthermore, when a range of numerical values ​​is mentioned herein, unless otherwise stated, the range shall include its endpoints and all integers and fractions within the range.

[0051] In this document, numerical values ​​are to be understood as having a certain number of significant digits, provided that the purpose of the invention is achieved. For example, the number 40 is to be understood as covering the range from 39.50 to 40.49, and the number 40.0 is to be understood as covering the range from 39.95 to 40.04.

[0052] In this document, when Markush groups or alternative terms are used to describe features or examples of the invention, those skilled in the art should understand that subgroups of all members within a Markush group or option list, or any individual member, can also be used to describe the invention. For example, if X is described as "selected from the group consisting of X1, X2, and X3," it also indicates that the claim that X is X1 and the claim that X is X1 and / or X2 and / or X3 have been fully described. Furthermore, when Markush groups or alternative terms are used to describe features or examples of the invention, those skilled in the art should understand that any combination of subgroups of all members within a Markush group or option list, or any individual member, can also be used to describe the invention. Accordingly, for example, if X is described as "selected from the group consisting of X1, X2, and X3," and Y is described as "selected from the group consisting of Y1, Y2, and Y3," it indicates that the claim that X is X1 or X2 or X3 and Y is Y1 or Y2 or Y3 has been fully described. In this article, "or a combination thereof" means "or any combination thereof".

[0053] In this document, the phrase "a composition comprising A, B, and C, wherein A comprises a1, a2, or a3" is used, which is equivalent to "a composition comprising A, B, and C, wherein A comprises a1, a2, a3, or a combination thereof," that is, "a composition comprising A, B, and C, wherein A comprises a1, a2, a3, a combination of a1 and a2, a combination of a1 and a3, a combination of a2 and a3, or a combination of a1, a2, and a3."

[0054] In this paper, the term "isomer" refers to compounds that have the same molecular formula but differ in the bonding properties or sequence of their atoms or the spatial arrangement of their atoms.

[0055] Unless otherwise specified, "resin" can generally be a common name for a synthetic polymer. However, in this invention, "resin" can be interpreted as monomers, polymers thereof, combinations of monomers, combinations of polymers thereof, or combinations of monomers and their polymers, and is not limited thereto. For example, "maleimide resin" can be interpreted as maleimide monomers (maleimide small molecule compounds), maleimide polymers, combinations of maleimide monomers, combinations of maleimide polymers, or combinations of maleimide monomers and maleimide polymers.

[0056] Unless otherwise specified, in this invention, a compound refers to a chemical substance formed by two or more elements linked by chemical bonds, including, but not limited to, small molecule compounds and polymeric compounds. In this invention, a compound is not limited to a single chemical substance, but can also be interpreted as a class of chemical substances having the same component or the same properties. Furthermore, in this invention, a mixture refers to a combination of two or more compounds, and mixtures may also contain copolymers or other auxiliaries, etc., and are not limited thereto.

[0057] Unless otherwise specified, in this invention, a polymer refers to the product formed by the polymerization reaction of monomers, often including aggregates of many high molecules. Each high molecule is composed of many simple structural units linked by repeated covalent bonds, and the monomer is the compound that synthesizes the polymer. Polymers may include homopolymers (also known as self-polymers), copolymers, prepolymers, etc., but are not limited to these.

[0058] Homopolymers are chemical substances formed by the polymerization, addition polymerization, or condensation polymerization of a single compound. Copolymers are chemical substances formed by the polymerization, addition polymerization, or condensation polymerization of two or more compounds, including random copolymers (structures such as -AABABBBAAABBA-), alternating copolymers (structures such as -ABABABAB-), graft copolymers (structures shown below), and block copolymers (structures such as -AAAAA-BBBBBB-AAAAA-). Unless otherwise specified, in this invention, a prepolymer refers to a polymer with a lower molecular weight, between that of the monomer and the final polymer, and the prepolymer contains reactive functional groups that can be further polymerized to obtain a fully cross-linked or hardened product with a higher molecular weight.

[0059] The graft copolymer structure can be, for example:

[0060] Polymers certainly include oligomers, but are not limited to them. Oligomers, also known as low-molecular-weight polymers, are polymers composed of 2 to 20 repeating units, but are usually composed of 2 to 5 repeating units.

[0061] Unless otherwise specified, in this invention, modified products (also referred to as modified materials) include products after modification of the reactive functional groups of each resin, products after prepolymerization of each resin with other resins, products after crosslinking of each resin with other resins, products after homopolymerization of each resin, products after copolymerization of each resin with other resins, etc. For example, but not limited to, modification may involve replacing the original hydroxyl groups with vinyl groups through a chemical reaction, or obtaining terminal hydroxyl groups by chemically reacting the original terminal vinyl groups with p-aminophenol.

[0062] Unless otherwise specified, the alkyl, alkenyl, and hydrocarbon groups mentioned in this invention are interpreted to include their various isomers. For example, propyl should be interpreted to include n-propyl and isopropyl.

[0063] Unless otherwise specified, "containing vinyl groups" in this invention refers to compounds containing an vinyl carbon-carbon double bond (C=C) or its derived functional groups. Therefore, examples of vinyl-containing compounds include, but are not limited to, compounds containing vinyl, allyl, vinyl benzyl, or methacrylate functional groups. Unless otherwise specified, the position of the aforementioned functional groups is not particularly limited; for example, they may be located at the end of a long chain structure.

[0064] Unless otherwise specified, the unsaturated bond referred to in this invention refers to a reactive unsaturated bond, such as, but not limited to, an unsaturated double bond that can undergo cross-linking reactions with other functional groups, such as, but not limited to, an unsaturated carbon-carbon double bond that can undergo cross-linking reactions with other functional groups.

[0065] In this article, parts by weight represent the number of parts by weight, which can be any unit of weight, such as, but not limited to, kilograms, grams, pounds, etc. For example, 100 parts by weight of maleimide resin means that it can be 100 kilograms of maleimide resin or 100 pounds of maleimide resin.

[0066] The following detailed embodiments are merely illustrative in nature and are not intended to limit the invention or its uses. Furthermore, this document is not limited to the foregoing prior art or the invention itself, or to any theory described in the following detailed embodiments or examples. Unless otherwise stated, the methods, reagents, and conditions used in the examples are conventional methods, reagents, and conditions in the art.

[0067] Phosphorus compounds

[0068] As previously stated, this invention primarily discloses a phosphorus-containing compound having the structure shown in formula (I):

[0069]

[0070] Where n is 0 or 1, and the Ar group represents a divalent aromatic hydrocarbon group.

[0071] For example, in one embodiment, the type of the aforementioned divalent aromatic hydrocarbon group is not particularly limited, such as it may be benzoxyl, naphthyl or biphenylxyl, and is not limited thereto.

[0072] For example, in one embodiment, the aforementioned benzoxyl group may be 1,2-benzoxyl, 1,3-benzoxyl, or 1,4-benzoxyl, preferably 1,4-benzoxyl, but is not limited thereto. The aforementioned naphthyl group may be 1,2-naphthyl, 1,3-naphthyl, 1,4-naphthyl, 1,5-naphthyl, 1,6-naphthyl, 1,7-naphthyl, 1,8-naphthyl, 2,3-naphthyl, 2,6-naphthyl, or 2,7-naphthyl, particularly 1,5-naphthyl or 1,6-naphthyl, but is not limited thereto. The aforementioned biphenylxyl group may be 2,2'-biphenylxyl, 2,3'-biphenylxyl, 2,4'-biphenylxyl, 3,3'-biphenylxyl, 3,4'-biphenylxyl, or 4,4'-biphenylxyl, particularly 4,4'-biphenylxyl, but is not limited thereto.

[0073] For example, in one embodiment, in the structure shown in formula (I), the Ar group may be an unsubstituted divalent aromatic hydrocarbon group.

[0074] For example, in another embodiment, in the structure shown in formula (I), the Ar group may be a substituted divalent aromatic hydrocarbon group. For example, in one embodiment, the substituent on the Ar group may be an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an alkylamine group having 1 to 4 carbon atoms, a phenyl group, or a benzyl group, and is not limited thereto.

[0075] In the structure shown in formula (I), n can be 0 or 1. When n is 0, the phosphorus atom (P) is directly attached to the Ar group. When n is 1, the phosphorus atom (P) is attached to the Ar group via an oxygen atom (O). For example, in one embodiment, when n is 0, the terminal vinyl and phosphorus atoms in the structure shown in formula (I) can be located at any two substitution sites of the divalent aromatic hydrocarbon group (i.e., the Ar group). For example, in another embodiment, when n is 1, the terminal vinyl and oxygen atoms in the structure shown in formula (I) can be located at any two substitution sites of the divalent aromatic hydrocarbon group (i.e., the Ar group).

[0076] For example, in one embodiment, the Ar group in the structure shown in formula (I) is a benzene group. In other words, the aforementioned phosphorus-containing compound can have the structure shown in formula (II):

[0077]

[0078] As can be seen from the structure shown in formula (II), the terminal vinyl group can be located at any substitution site on the benzene ring. For example, in one embodiment, the terminal vinyl group can be located at the para position on the benzene ring, as shown in formula (III), but is not limited thereto.

[0079]

[0080] As can be seen from the structures shown in Formula (I), Formula (II), or Formula (III), the phosphorus-containing heterospirocyclic structure of the aforementioned compounds provided by the present invention possesses structural symmetry, good thermal stability, and is rich in phosphorus and carbon elements, thus exhibiting good flame retardancy. Furthermore, the phosphorus-containing compounds having the structures shown in Formula (I), Formula (II), or Formula (III) have reactive double bonds at both ends, which can crosslink with resin to form an interconnected network, enabling materials such as copper-clad laminates to possess high glass transition temperatures and low coefficients of thermal expansion. For example, in one embodiment, the phosphorus-containing compound with the structure shown in Formula (I), Formula (II), or Formula (III) has a phosphorus content of 9% to 15% (including 9%, 10%, 11%, 12%, 13%, 14%, or 15%), for example, between 13% and 15%, and is not limited thereto.

[0081] On the other hand, the phosphorus-containing compounds with structures shown in Formula (I), Formula (II) or Formula (III) provided by the present invention are reactive phosphorus-containing flame retardants. Compared with additive phosphorus-containing flame retardants, they can participate in cross-linking reactions and can effectively prevent the migration, precipitation, detachment or cross-linking gaps of phosphorus-containing flame retardants in materials such as copper-clad laminates.

[0082] For example, phosphorus-containing compounds having the structures shown in Formula (I), Formula (II), or Formula (III) contain at least two vinyl reactive functional groups and can participate in the reaction, thus also serving as crosslinking agents. For example, phosphorus-containing compounds having the structures shown in Formula (I), Formula (II), or Formula (III) in maleimide (BMI) resin systems can achieve one, more, or all of the following effects: improved glass transition temperature, Z-axis thermal expansion coefficient, T288 heat resistance, flame retardancy, flame retardant migration, flame retardant shedding, and crosslinking gap.

[0083] Preparation of phosphorus-containing compounds

[0084] The aforementioned phosphorus-containing compounds having the structures shown in formula (I), formula (II) or formula (III), or collectively referred to as the phosphorus-containing compounds of the present invention, can be prepared by various methods.

[0085] For example, in one embodiment, the method for preparing the phosphorus-containing compound of the present invention includes: reacting a compound with the structure shown in formula (A) with a compound with the structure shown in formula (B) to obtain the phosphorus-containing compound of the present invention:

[0086]

[0087] Wherein, X represents a hydroxyl group or a magnesium halide group (e.g., but not limited to magnesium chloride or magnesium bromide), and Ar represents a divalent aromatic hydrocarbon group (e.g., but not limited to benzoxyl, naphthyl, or biphenylxyl).

[0088] The compound with the structure shown in formula (A) can be synthesized by known methods or obtained commercially. For example, in one embodiment, the aforementioned preparation method further includes reacting pentaerythritol with phosphorus oxychloride to prepare the compound with the structure shown in formula (A).

[0089] For example, in one embodiment, a method for preparing a phosphorus-containing compound having the structure shown in formula (I) includes: reacting pentaerythritol with phosphorus oxychloride to obtain an intermediate product pentaerythritol diphosphate diphosphonate chloride (i.e., a compound with the structure shown in formula (A)); and then reacting the intermediate product with hydroxystyrene (one of the states of a compound with the structure shown in formula (B), such as, but not limited to, 2-hydroxystyrene, 3-hydroxystyrene, or 4-hydroxystyrene) to obtain a phosphorus-containing compound having the structure shown in formula (I), wherein n is 1.

[0090] For example, in one embodiment, pentaerythritol and phosphorus oxychloride can be reacted by heating and reflux in a reactor for a reaction time that can be between 2 hours and 10 hours, for example, between 4 hours and 8 hours, or between 6 hours and 7 hours, and is not limited thereto.

[0091] For example, in one embodiment, the molar ratio of pentaerythritol to phosphorus oxychloride can be between 1:3 and 1:5, and is not limited thereto. After the reaction is complete, excess phosphorus oxychloride can be removed to obtain the intermediate pentaerythritol diphosphate diphosphoryl chloride, and the reaction yield of pentaerythritol diphosphate diphosphoryl chloride can be, for example, 60% to 70%.

[0092] For example, in one embodiment, a solvent may be added to the reaction of pentaerythritol diphosphate diphosphonate chloride with hydroxystyrene, and the solvent may include, but is not limited to, acetonitrile, dichloromethane, dichloroethane, acetone, chloroform, benzene, toluene, tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, ethyl acetate, dioxane, chlorobenzene, or combinations thereof. The amount of solvent is not particularly limited, as long as it is sufficient to dissolve the above components and allow the reaction to proceed.

[0093] For example, in one embodiment, an acid-binding agent may be added to the reaction of pentaerythritol diphosphate diphosphonate chloride with hydroxystyrene. The type of acid-binding agent is not particularly limited, but specific examples include, but are not limited to, triethylamine, diisopropylethylamine, pyridine, or hexahydropyridine, such as N,N-diisopropylethylamine. The amount of acid-binding agent is not particularly limited, as long as it is sufficient to absorb the acid generated in the reaction so that it does not affect the reaction.

[0094] For example, in one embodiment, pentaerythritol diphosphate diphosphoryl chloride is reacted with hydroxystyrene by heating. For example, in one embodiment, the molar ratio of pentaerythritol diphosphate diphosphoryl chloride to hydroxystyrene is between 1:3 and 1:5. For example, in one embodiment, the heating temperature can be between 50°C and 80°C, for example, between 60°C and 70°C. For example, in one embodiment, the reaction time is between 14 hours and 20 hours, for example, between 14 hours and 18 hours, or for example, between 16 hours and 17 hours. For example, in one embodiment, after the aforementioned reaction is completed, the reaction solution can be subjected to rotary evaporation under reduced pressure to obtain a crude product (a phosphorus-containing compound having the structure shown in formula (I), formula (II), or formula (III), where n is 1), which can be further purified by column chromatography as needed, with a yield of, for example, 40% to 60%.

[0095] For example, in another embodiment, a method for preparing a phosphorus-containing compound having the structure shown in formula (I) includes: reacting pentaerythritol with phosphorus oxychloride to obtain an intermediate product, pentaerythritol diphosphate diphosphonate chloride (i.e., a compound with the structure shown in formula (A)); and then reacting the intermediate product with styryl magnesium halide (one of the states of a compound with the structure shown in formula (B), such as, but not limited to, 2-styryl magnesium bromide, 3-styryl magnesium bromide, 4-styryl magnesium bromide, 2-styryl magnesium chloride, 3-styryl magnesium chloride, or 4-styryl magnesium chloride) to obtain a phosphorus-containing compound having the structure shown in formula (I), wherein n is 0.

[0096] For example, in one embodiment, the reaction of pentaerythritol diphosphate diphosphoryl chloride with styrene magnesium halide is carried out in the absence of an acid-binding agent.

[0097] For example, in one embodiment, a solvent may be added to the reaction of pentaerythritol diphosphate diphosphonate chloride with styrene-based magnesium halide, and the solvent may include, but is not limited to, acetonitrile, dichloromethane, dichloroethane, acetone, chloroform, benzene, toluene, tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, ethyl acetate, dioxane, chlorobenzene, or combinations thereof. The amount of solvent is not particularly limited, as long as it is sufficient to dissolve the above components and allow the reaction to proceed.

[0098] For example, in one embodiment, pentaerythritol diphosphate diphosphoryl chloride is reacted with styrene magnesium halide by heating. For example, in one embodiment, the molar ratio of pentaerythritol diphosphate diphosphoryl chloride to styrene magnesium halide is between 1:3 and 1:5. For example, in one embodiment, the heating temperature can be between 50°C and 80°C, for example, between 60°C and 70°C. For example, in one embodiment, the reaction time is between 2 hours and 18 hours, for example, between 4 hours and 16 hours, or for example, between 6 hours and 14 hours. For example, in one embodiment, after the aforementioned reaction is completed, the reaction solution can be subjected to rotary evaporation under reduced pressure to obtain a crude product (a phosphorus-containing compound having the structure shown in formula (I), formula (II), or formula (III), where n is 0), which can be further purified by column chromatography as needed, with a yield of, for example, 40% to 60%.

[0099] Synthesis and qualitative analysis of phosphorus-containing compounds

[0100] Synthesis example 1

[0101] In a three-necked flask, a thermometer and a condenser were inserted. 2 moles (approximately 272 g) of pentaerythritol and 6 moles (approximately 920 g) of phosphorus oxychloride were added. The solution was heated to reflux for 6 hours. After the reaction was complete, excess phosphorus oxychloride was removed by rotary evaporation under reduced pressure to obtain a white solid intermediate, pentaerythritol diphosphate diphosphoryl chloride, with a yield of approximately 68%.

[0102] In a three-necked flask, a thermometer and a condenser were inserted. 1 mole of pentaerythritol diphosphate diphosphonate chloride (approximately 296 g), a suitable amount of chlorobenzene solvent, 3 moles of 4-hydroxystyrene (approximately 360 g), and a suitable amount of acid-binding agent N,N-diisopropylethylamine were added. The mixture was heated to 60°C and reacted for 16 hours. After the reaction was complete, excess 4-hydroxystyrene was removed by rotary evaporation to obtain a white solid product, which is the phosphorus-containing compound of the present invention (structure shown below), with a yield of approximately 50%. The phosphorus content of the above-mentioned phosphorus-containing compound was calculated (relative atomic weight of phosphorus atoms * number / molecular weight of the compound * 100%), for example, between 9% and 15%, preferably between 13% and 15%.

[0103]

[0104] Melting point tests were performed on the purified phosphorus-containing compounds, revealing that their melting points ranged from 198.4°C to 200.7°C, for example, between 198°C and 201°C, or between 199°C and 200°C. Furthermore, thermogravimetric analysis (TGA) was performed on the purified phosphorus-containing compounds. The TGA results confirmed that when the phosphorus-containing compound decomposed by 1%, its thermal decomposition temperature 1 was 384.03°C; when it decomposed by 2%, its thermal decomposition temperature 2 was 398.61°C; and when it decomposed by 5%, its thermal decomposition temperature 3 was 403.61°C.

[0105] The aforementioned melting point test method refers to Method B, Section 1 of General Chapter 0612, Melting Point Determination, Part IV of the 2020 edition of the Chinese Pharmacopoeia. The specific steps include: after drying the sample, taking an appropriate amount and placing it in a capillary tube for melting point determination; heating the heating block of the automatic melting point apparatus to 190°C; inserting the capillary tube containing the sample into the heating block; continuing to heat; adjusting the heating rate to 1.0°C per minute; heating to 215°C; repeating the determination 5 times; and taking the average value to obtain the melting point.

[0106] The aforementioned thermogravimetric analysis was performed according to the method described in IPC-TM-650 2.4.24.6. The specific steps included: baking the copper-free substrate 1 (prepared as described below) at 120°C for 2 hours, and then cooling it in a drying oven for 30 minutes. Next, a sample of 25±5 mg was taken from the copper-free substrate 1 and placed in the thermogravimetric analyzer. Under a nitrogen atmosphere, the sample was heated to 550°C at a heating rate of 10°C / min, and the temperatures corresponding to 1%, 2%, and 5% weight loss were recorded.

[0107] In addition, the phosphorus-containing compound prepared in Synthesis Example 1 was purified and subjected to Fourier Transmission Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance Spectroscopy (NMR) analyses, respectively. 1 H NMR and 31 The results of the analysis by P NMR and liquid chromatography-mass spectrometry (LC-MS) are described below.

[0108] Figure 1 The FTIR spectrum of the phosphorus-containing compound prepared in Synthesis Example 1 shows that at 1600 cm⁻¹... -1 With 1502cm -1 The absorption peak at 3078 cm⁻¹ confirms the presence of a benzene ring skeleton in this phosphorus-containing compound. -1 With 1630cm -1 The absorption peak at 1300 cm⁻¹ is the C=CH group. -1 The absorption peak at 1152 cm⁻¹ is P=O. -1 With 1017cm -1 The absorption peak of POC is at 852 cm⁻¹. -1With 771cm -1 The peak at this point is the vibrational absorption peak of the pentaerythritol spirocyclic carbon skeleton, which is consistent with the expected structure of Synthetic Example 1, preliminarily proving that a phosphorus-containing compound with the structure shown in Formula (I) has been synthesized.

[0109] Figure 2 The phosphorus-containing compound prepared in Synthesis Example 1 1 The 1H NMR spectrum reveals that this phosphorus-containing compound contains six hydrogen atoms with different chemical environments, each corresponding to... 1 The chemical shifts of hydrogen atoms at six positions in the 1H NMR spectrum are as follows: chemical shifts (δ) 4.2–5.0 ppm represent hydrogen atoms in the -CH2- group of pentaerythritol; chemical shifts 5.2–6.0 ppm represent hydrogen atoms in the -CH2- group of the terminal vinyl group; chemical shifts 6.5–7.0 ppm represent hydrogen atoms in the -CH- group of the terminal vinyl group; and chemical shifts 7.3–7.6 ppm represent hydrogen atoms in the two -CH- groups of the benzene ring (adjacent to the C atoms on the benzene ring in the -CO- bond of the vinylphenoxy group, and adjacent to the C atoms on the benzene ring in the -CC- bond of the vinylphenoxy group, respectively). This is sufficient to confirm that a phosphorus-containing compound with the structure shown in formula (I) has been synthesized.

[0110] Furthermore, the structure described above confirms that the phosphorus-containing compound prepared in Synthetic Example 1 has two phosphorus atoms in the same chemical environment. Accordingly, the phosphorus-containing compound prepared in Synthetic Example 1... 31 The P NMR spectrum results showed only one peak at a chemical shift of -13.666 ppm, indicating that this phosphorus-containing compound contains only one type of phosphorus atom in a chemical environment. It also indicates that this phosphorus-containing compound has a symmetrical structure, which is consistent with the expected structure of Synthetic Example 1.

[0111] Figure 3 The LC-MS spectrum of the phosphorus-containing compound prepared in Example 1 shows that the molecular weight of the compound was calculated to be 464.35. Comparing this with the theoretical molecular weight calculated from the molecular structure of the phosphorus-containing compound, the molecular weight test result is consistent with the theoretical molecular weight, indicating that the phosphorus-containing compound has been synthesized.

[0112] Synthesis example 2

[0113] Pentaerythritol diphosphate diphosphoryl chloride was prepared according to the method described in Synthetic Example 1. Without the addition of an acid-binding agent, 3 moles of 4-styrene-based magnesium chloride (approximately 495 g, purchased from Suzhou Siasun) and 1 mole of pentaerythritol diphosphate diphosphoryl chloride (approximately 296 g) were reacted in a three-necked flask at 60°C for 8 hours. After the reaction was complete, excess 4-styrene-based magnesium chloride was removed by rotary evaporation under reduced pressure to give a white solid product, which was a phosphorus-containing compound having the structure shown in Formula (I) (structure shown below), with a yield of approximately 45%.

[0114]

[0115] In Synthesis Example 2, 4-styryl magnesium chloride can also be replaced by other organomagnesium halides, such as, but not limited to, 4-styryl magnesium bromide. The structures of 4-styryl magnesium chloride and 4-styryl magnesium bromide are shown below, respectively.

[0116]

[0117] Resin Composition

[0118] As mentioned above, another major object of the present invention is to provide a resin composition comprising 100 parts by weight of maleimide resin and 10 to 80 parts by weight of a phosphorus-containing compound having the structure shown in formula (I).

[0119] In one embodiment, the maleimide resin may be a multifunctional maleimide resin. In one embodiment, the maleimide resin may include 4,4'-diphenylmethane bismaleimide, benzene maleimide oligomer, biphenyl aryl bismaleimide, indane-containing bismaleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 2,3-dimethylbenzenemaleimide, 2,6-dimethylbenzenemaleimide, N-phenylmaleimide, and resins containing C5 to C64. 50 Maleimide resins with aliphatic long-chain structures, or combinations thereof, but not limited to these.

[0120] For example, the maleimide resin may be a maleimide resin produced by Daiwa Kasei Corporation under trade names such as BMI-1000, BMI-1000H, BMI-1100, BMI-1100H, BMI-2000, BMI-2300, BMI-3000, BMI-3000H, BMI-4000H, BMI-5000, BMI-5100, BMI-7000, and BMI-7000H; or a maleimide resin produced by KI Chemicals Corporation under trade names such as BMI-70 and BMI-80; or a maleimide resin produced by Nippon Kayaku Corporation under trade names such as MIR-3000 and MIR-5000; or a maleimide resin produced by DIC (Dai Nippon Ink Chemicals) Corporation under trade names such as X9-470, NE-X-9470S, and NE-X-9480.

[0121] For example, the C5 to C 50Aliphatic long-chain maleimide resins, marketed under trade names such as BMI-689, BMI-1400, BMI-1500, BMI-1700, BMI-2500, BMI-3000, BMI-5000, and BMI-6000, are maleimide resins manufactured by the designer's subsidiaries. They contain C5 to C6... 50 Maleimide resins with aliphatic long-chain structures may have at least one C5 to C6 bond with substituted or unsubstituted bonds. 50 Maleimide functional groups linked to long-chain aliphatic groups. The C5 to C6... 50 The carbon number of aliphatic long-chain structures can be C. 10 To C 50 C 20 To C 50 C 30 To C 50 C 20 To C 40 Or C 30 To C 40 However, this is not the only example. For instance, commercially available maleimide resins containing aliphatic long-chain structures include: BMI-689. BMI-1400: BMI-1500: BMI-1700: BMI-2500:

[0122] BMI-3000, BMI-5000, BMI-6000:

[0123]

[0124] For example, in one embodiment, the resin composition comprises 100 parts by weight of maleimide resin and 20 to 70 parts by weight of a phosphorus-containing compound having the structure shown in formula (I).

[0125] For example, in one embodiment, the resin composition may further include amine curing agents, inorganic fillers, curing accelerators, polymerization inhibitors, colorants, solvents, toughening agents, silane coupling agents, or combinations thereof.

[0126] In this invention, for example, the amine curing agent can be any type of amine curing agent known in the art. Specific examples include, but are not limited to, at least one or a combination of diaminodiphenyl sulfone, diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfide, and dicyandiamide. Unless otherwise specified, in the resin composition of this invention, the amount of amine curing agent used is not particularly limited relative to 100 parts by weight of maleimide resin, for example, it can be from 1 part by weight to 15 parts by weight, such as, but not limited to, 1 part by weight, 4 parts by weight, 7.5 parts by weight, 12 parts by weight, or 15 parts by weight.

[0127] In one embodiment, the resin composition includes an inorganic filler. The inorganic filler may be any one or more fillers suitable for making resin films, prepregs, laminates, printed circuit boards, or cured insulators. The inorganic filler may be silica (molten, non-molten, porous, or hollow), alumina, aluminum hydroxide, magnesium oxide, magnesium hydroxide, calcium carbonate, aluminum nitride, boron nitride, silicon aluminum carbide, silicon carbide, titanium dioxide, zinc oxide, zirconium oxide, mica, boehmite (AlOOH), calcined talc, talc, silicon nitride, calcined kaolin, or combinations thereof, but is not limited thereto. The inorganic filler may be spherical, fibrous, plate-like, granular, flake-like, or needle-like. The inorganic filler may be pretreated with a silane coupling agent (especially an aminosilane coupling agent). The inorganic filler may be spherical silica with a surface treated with an aminosilane coupling agent. The amount of inorganic filler used is not particularly limited. In one embodiment, based on 100 parts by weight of all resins in the resin composition (excluding silane coupling agents, curing accelerators, solvents, and inorganic fillers), the resin composition may contain 20 to 300 parts by weight of inorganic fillers, preferably 50 to 250 parts by weight, but not limited thereto.

[0128] In one embodiment, the resin composition includes a curing accelerator. The curing accelerator may include catalysts such as Lewis bases and Lewis acids. Lewis bases may include, but are not limited to, imidazole, boron trifluoride amine complexes, ethyltriphenyl phosphonium chloride, 2-methylimidazole (2MI), 2-phenyl-1H-imidazole (2PZ), 2-ethyl-4-methylimidazole (2E4MI), triphenylphosphine (TPP), 4-dimethylaminopyridine (DMAP), or combinations thereof. Lewis acids may include metal salt compounds, such as manganese, iron, cobalt, nickel, copper, and zinc salts, particularly metal catalysts such as zinc octoate and cobalt octoate. The curing accelerator may include a curing initiator (i.e., a curing starter). The curing initiator may include a peroxide capable of generating free radicals. Curing initiators include, but are not limited to, 2,3-dimethyl-2,3-diphenylbutane, dicumyl peroxide, tert-butyl peroxide, tert-butyl isopropyl percarbonate, dibenzoyl peroxide (BPO), 2,5-dimethyl-2,5-di(tert-butylperoxy)-3-hexyne (25B), bis(tert-butylperoxyisopropyl)benzene, azobisisobutyronitrile, or combinations thereof. For example, in one embodiment, the resin composition may further include 0.01 to 2.0 parts by weight of a curing accelerator, preferably 0.3 to 1.5 parts by weight, but not limited to, relative to 100 parts by weight of maleimide resin.

[0129] In one embodiment, for example, the polymerization inhibitor described in this invention is not particularly limited, and may be any type of polymerization inhibitor known in the art, including but not limited to various commercially available polymerization inhibitor products. For example, the above-mentioned polymerization inhibitor may include, but is not limited to, 1,1-diphenyl-2-trinitrophenylhydrazine, methacrylonitrile, disulfide, nitroxide-stabilized free radicals, triphenylmethyl free radicals, metal ion free radicals, sulfur free radicals, hydroquinone, p-methoxyphenol, p-benzoquinone, phenthiazide, β-phenylnaphthylamine, p-tert-butylcatechol, methylene blue, 4,4'-butylenebis(6-tert-butyl-3-methylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), or combinations thereof. For example, the above-mentioned nitroxide-stabilized free radicals may include, but are not limited to, 2,2,6,6-substituted-1-piperidinoxy free radicals or 2,2,5,5-substituted-1-pyrrolidineoxy free radicals derived from cyclic hydroxylamines. As substituents, alkyl groups with 4 or fewer carbon atoms, such as methyl or ethyl, are preferred. Specific examples of nitroxide free radical compounds include 2,2,6,6-tetramethyl-1-piperidinoxy radical, 2,2,6,6-tetraethyl-1-piperidinoxy radical, 2,2,6,6-tetramethyl-4-oxo-1-piperidinoxy radical, 2,2,5,5-tetramethyl-1-pyrrolidineoxy radical, 1,1,3,3-tetramethyl-2-isodihydroindoleoxy radical, and N,N-di-tert-butylamineoxy radical. Stable free radicals such as galvinoxyl radicals can also be used instead of nitroxide free radicals. The polymerization inhibitor suitable for the resin compositions of the present invention can also be a product derived from the substitution of hydrogen atoms or groups in the inhibitor by other atoms or groups. For example, products derived from the substitution of hydrogen atoms in the inhibitor by groups such as amino, hydroxyl, or ketone carbonyl groups. For example, in one embodiment, the resin composition of the present invention may further include 0.001 to 2 parts by weight of a polymerization inhibitor relative to 100 parts by weight of maleimide resin.

[0130] In this invention, for example, the dyeing agent may include, but is not limited to, dyes or pigments.

[0131] In this invention, for example, the solvent can be any solvent suitable for dissolving the resin composition of this invention, including but not limited to: methanol, ethanol, ethylene glycol monomethyl ether, acetone, butanone (also known as methyl ethyl ketone), methyl isobutyl ketone, cyclohexanone, N-methylpyrrolidone, toluene, xylene, methoxyethyl acetate, ethoxyethyl acetate, propoxyethyl acetate, ethyl acetate, dimethylformamide, dimethylacetamide, propylene glycol methyl ether acetate, and other solvents or mixtures thereof. The amount of solvent added is intended to completely dissolve the resin and adjust to a specific total solids content of the resin composition. For example, in one embodiment, the amount of solvent added is adjusted to adjust the total solids content of the resin composition to 50% to 85% (by weight), but is not limited thereto. The solvent added to the resin composition can evaporate and be removed during the processing of the resin composition into products such as prepregs or resin films, so that the insulating layer of the prepregs or resin films contains no solvent or only a trace amount of solvent less than or equal to 3 wt% (i.e., 3% by weight). Therefore, the presence or absence of solvent in the resin composition does not affect the properties of the product.

[0132] In this invention, the main function of adding toughening agents is to improve the toughness of the resin composition. For example, toughening agents suitable for this invention may include, but are not limited to, carboxyl-terminated butadiene acrylonitrile rubber (CTBN), core-shell rubber, ethylene propylene rubber, and other compounds or combinations thereof.

[0133] In this invention, for example, the silane coupling agent may include silane compounds (e.g., including but not limited to siloxane compounds), which, according to the type of functional group, may be classified as amino silane compounds, epoxy silane compounds, vinyl silane compounds, hydroxy silane compounds, isocyanate silane compounds, methacryloxy silane compounds, and acryloyloxy silane compounds. For example, in one embodiment, relative to 100 parts by weight of maleimide resin, the resin composition of this invention may further include 0.001 parts by weight to 10 parts by weight of silane coupling agent, preferably 0.01 parts by weight to 5 parts by weight of silane coupling agent, but is not limited thereto.

[0134] Articles of resin composition

[0135] In addition to the aforementioned resin composition, the present invention also provides an article made from the above-described resin composition, for example, suitable for components in various electronic products, including but not limited to: prepregs, resin films, laminates, printed circuit boards, or cured insulators. The article may include the resin composition in a semi-cured (B-stage) or cured (C-stage) state. The article may include a resin layer, which is the resin composition in a semi-cured or cured state. The article may include an insulating layer, which is the resin composition in a cured state.

[0136] For example, the resin composition of the present invention can be made into a prepreg, which includes a reinforcing material and a layer disposed on the reinforcing material. The layer is obtained by heating the aforementioned resin composition at a high temperature to form a semi-cured state (B-stage). The baking temperature for making the prepreg is between 100°C and 200°C, preferably between 120°C and 160°C. The reinforcing material can be any of a fiber material, woven fabric, or nonwoven fabric, and the woven fabric preferably includes glass fiber cloth. There is no particular limitation on the type of glass fiber cloth; it can be any type of glass fiber cloth suitable for printed circuit boards, such as E-type glass fiber cloth, D-type glass fiber cloth, S-type glass fiber cloth, T-type glass fiber cloth, L-type glass fiber cloth, Q-type glass fiber cloth, or QL-type glass fiber cloth (a glass fiber cloth with a mixed structure made of Q glass and L glass). The types of glass fibers include yarn and roving, and the form includes open or closed fibers, with end face shapes including round or flat shapes. The aforementioned nonwoven fabric preferably includes liquid crystal resin nonwoven fabric, such as polyester nonwoven fabric, polyurethane nonwoven fabric, etc., but is not limited thereto. The aforementioned fabric may also include liquid crystal resin fabric, such as polyester fabric or polyurethane fabric, and is not limited thereto. This reinforcing material can increase the mechanical strength of the prepreg. In a preferred embodiment, the reinforcing material may also be selectively pretreated with a silane coupling agent. The prepreg subsequently undergoes heating and curing (C-stage) to form an insulating layer.

[0137] For example, the resin composition of the present invention can be made into a resin film, which is obtained by baking and heating the aforementioned resin composition to form a semi-cured state. The resin composition can be selectively coated onto a support material, including but not limited to liquid crystal resin film, polytetrafluoroethylene film, polyethylene terephthalate film (PET film), polyimide film (PI film), copper foil or resin-coated copper (RCC), and then baked and heated to form a semi-cured state, so that the resin composition forms a resin film.

[0138] For example, the resin composition of the present invention can be used to form various laminates comprising at least two metal foils and at least one insulating layer disposed between the two metal foils. The insulating layer can be formed by curing the aforementioned resin composition under high temperature and high pressure (C-stage). Applicable curing temperatures are, for example, between 180°C and 250°C, preferably between 210°C and 240°C, and the curing time is 80 to 180 minutes, preferably 100 to 150 minutes. The aforementioned insulating layer can be obtained by curing the aforementioned prepreg or resin film. The aforementioned metal foils can be made of copper, aluminum, nickel, platinum, silver, gold, or alloys thereof, such as copper foil. In a preferred embodiment, the laminate is a copper foil substrate.

[0139] In one embodiment, the aforementioned multilayer board can be further processed into a printed circuit board.

[0140] For example, in one embodiment, the resin composition of the present invention can also be made into a cured insulator, which is obtained by curing the aforementioned resin composition through a single curing process or through multiple curing processes, wherein multiple curing refers to two or more curing processes. For example, the aforementioned resin composition can be semi-cured (B-stage) first, and then further cured (C-stage) to obtain a cured insulator. The cured insulator may include the cured resin composition, the cured resin composition containing reinforcing material, or a combination thereof. The semi-curing or curing method is preferably heating, such as baking heating. In one embodiment, the suitable semi-curing temperature may be, for example, between 100°C and 200°C, preferably between 120°C and 160°C. The suitable curing temperature may be, for example, between 180°C and 250°C, preferably between 210°C and 240°C. The suitable curing time may be, for example, between 80 and 180 minutes, preferably between 100 and 150 minutes. The aforementioned curing (C-stage) method can be further carried out under pressure.

[0141] The aforementioned cured insulator may include the cured resin composition. In one embodiment, the present invention provides a method for preparing a cured insulator, comprising: curing the resin film. The method for preparing a cured insulator may include: coating the resin composition onto a substrate (e.g., polyethylene terephthalate film (PET film), polyimide film (PI film), copper foil, or adhesive-backed copper foil); semi-curing the resin composition to form a resin film; and curing the resin film. The semi-curing or curing method is preferably heating, such as baking.

[0142] The cured insulator may include the cured resin composition in a cured state containing reinforcing material. In some embodiments, the present invention provides a method for preparing a cured insulator, comprising: curing the prepreg. The method for preparing a cured insulator may include: disposing a resin composition on the aforementioned reinforcing material; semi-curing the resin composition to form a prepreg comprising the reinforcing material and a semi-cured layer; and curing the prepreg. The semi-curing or curing method is preferably heating, such as baking.

[0143] The method for preparing the cured insulator may include molding. For example, the resin composition or semi-cured resin composition may be placed in a mold, and the resin composition or semi-cured resin composition may be formed and cured in the mold under curing temperature and certain pressure to obtain a cured insulator of a specific shape.

[0144] The cured insulator may be an insulating layer with a metal-free surface obtained by removing the surface metal foil from the aforementioned laminate or printed circuit board.

[0145] Preferably, resin compositions or articles thereof comprising phosphorus-containing compounds having the structure shown in Formula (I) of the present invention can be improved in one or more aspects such as glass transition temperature, Z-axis thermal expansion coefficient, T288 heat resistance, flame retardancy, flame retardant migration, flame retardant shedding, and crosslinking gap.

[0146] For example, in one embodiment, the resin composition disclosed in this invention and various articles prepared therefrom preferably have one, more, or all of the following characteristics:

[0147] The glass content measured using a dynamic mechanical analyzer is obtained by referring to the method described in IPC-TM-650 2.4.24.4.

[0148] Glass transition temperature is greater than or equal to 245°C, for example, between 245°C and 269°C, or between

[0149] Between 258℃ and 269℃;

[0150] The Z-axis thermal expansion coefficient, as measured by a thermomechanical analyzer according to the method described in IPC-TM-650 2.4.24.5, is less than or equal to 1.45%, for example, between 0.95% and 1.45%, or between 0.95%.

[0151] And between 1.21%;

[0152] The non-explosiveness was measured using a thermomechanical analyzer according to the method described in IPC-TM-650 2.4.24.1.

[0153] The board time is greater than or equal to 50 minutes, for example, the time without board explosion is greater than or equal to 60 minutes;

[0154] Flame retardancy measured according to the method described in UL 94 specification is rated V-0 or V-1.

[0155] For example, the flame retardancy rating is V-0;

[0156] Visually confirmed that no flame retardant has migrated into the product (e.g., a sample tested for flame retardant migration).

[0157] SEM observation confirmed that no flame retardant had detached from the product (e.g., the sample tested for flame retardant detachment).

[0158] as well as

[0159] SEM observation confirmed that there were no cross-linking gaps in the product (e.g., the cross-linking gap test sample).

[0160] The resin compositions of the embodiments and comparative examples of the present invention were prepared according to the amounts specified in Tables 1 to 3 using various raw materials from the following sources, and further processed into various test samples or articles. The composition and test results of the resin compositions of the embodiments and comparative examples of the present invention are shown in Tables 1 to 3 (all units are parts by weight).

[0161] X9-470: Contains indene-structured bismaleimide, purchased from DIC.

[0162] MIR-5000: The structural formula is as follows, purchased from Nippon Kayaku Co., Ltd. Where 1≤n≤5.

[0163]

[0164] Phosphorus-containing compound 1: prepared from synthesis example 1.

[0165] Phosphorus-containing compound 2: prepared from synthesis example 2.

[0166] FCX-210: The structure is as follows, purchased from Teijin Corporation.

[0167]

[0168] PX-200: Resorcinol bis-(xylyl phosphate) (condensation polymer), or tetra(2,6-dimethylphenyl) phosphate (condensation polymer), purchased from Daihachi Chemical, Japan.

[0169] Comparative compound 1: Prepared according to the following method.

[0170] One mole of pentaerythritol diphosphate diphosphonate chloride (approximately 296 g), an appropriate amount of chlorobenzene solvent, and three moles of vinyl magnesium chloride (approximately 260 g) were added to a three-necked flask, and the mixture was heated to 60 °C and reacted for 8 hours. After the reaction was completed, excess vinyl magnesium chloride was removed by rotary evaporation under reduced pressure to obtain a white solid product, which is the comparative compound 1, having the following structure.

[0171]

[0172] Comparative compound 2: prepared according to the following method.

[0173] One mole of pentaerythritol diphosphate diphosphonate chloride (approximately 296 g), an appropriate amount of chlorobenzene solvent, an appropriate amount of acid-binding agent N,N-diisopropylethylamine, and three moles of 4-hydroxybenzene (approximately 282 g) were added to a three-necked flask, and the mixture was heated to 60 °C and reacted for 16 hours. After the reaction was completed, excess 4-hydroxybenzene was removed by rotary evaporation under reduced pressure to obtain a white solid product, which is the comparative compound 2, having the following structure.

[0174]

[0175] Stilbene pentaerythritol diphosphite: purchased from Zhejiang Wansheng Co., Ltd.

[0176] Allyl phosphate: The structural formula is as follows, and it is prepared according to the method described in the patent specification CN110938234A.

[0177]

[0178] 25B: 2,5-Dimethyl-2,5-Di(tert-butylperoxy)-3-hexyne, purchased from Nippon Oil Co., Ltd.

[0179] SC-2500SMJ: Spherical silica treated with acrylate-based silane coupling agent, purchased from [source missing].

[0180] Admatechs.

[0181] Toluene: Purchased from Qiangdi Enterprise Co., Ltd.

[0182] Butyl ketone (MEK): Commercially available, source is not limited.

[0183] In the table, "Z" represents the total amount of all components in the resin compositions of each group of examples or comparative examples, excluding (i.e., not containing) curing accelerators, inorganic fillers, and solvents. For example, "Z*1.0"

[0184] The amount of inorganic filler added is 1.0 times that of Z mentioned above. For example, "Z*1.0" in Example E1 represents an amount of inorganic filler added of 150 parts by weight (150 parts by weight multiplied by 1.0). "Suitable" solvent addition in the table represents the amount of solvent used to achieve the ideal solid content of the overall resin composition. For resin compositions using both methyl ethyl ketone (MEK) and toluene as solvents, "Suitable" means that the total amount of these two solvents results in the ideal solid content of the overall resin composition, for example, but not limited to, a solid content of 70% by weight.

[0185] The resin composition and test results of the embodiments and comparative examples of the present invention are shown in Tables 1 to 3 (all units are parts by weight):

[0186] [Table 1] Composition (parts by weight) and property test results of the resin compositions in the examples

[0187] [Table 2] Composition (parts by weight) and property test results of the resin compositions in the examples

[0188]

[0189] [Table 3] Composition (parts by weight) and property test results of comparative example resin compositions

[0190]

[0191] The various resin compositions shown in Tables 1 to 3 were prepared with varnish and various test samples according to the following methods, and their properties were measured according to specific test conditions to obtain test results.

[0192] 1. Varnish (or adhesive)

[0193] Each embodiment (represented by E, such as E1 to E10) or comparative example (represented by C, such as C1 to C6) is added to a mixing tank according to the amounts in Tables 1 to 3 and stirred. The resin composition formed after uniform mixing is called resin varnish.

[0194] Taking Example E1 as an example, 100 parts by weight of maleimide resin (X9-470) and 20 parts by weight of phosphorus-containing compound 1 were added to a stirrer containing an appropriate amount of toluene and an appropriate amount of methyl ethyl ketone (the solvent "appropriate amount" in Tables 1 to 3 represents the amount of solvent used to obtain the ideal solid content of the resin composition, for example, the solid content of the varnish is 70% by weight). The mixture was stirred until all solid components were dissolved into a homogeneous liquid phase. Then, "Z*1.0" parts by weight of spherical silica (SC-2500SMJ, i.e., 150 parts by weight) were added and stirred until completely dispersed. Then, 0.5 parts by weight of curing accelerator (25B, which was first dissolved in an appropriate amount of solvent) was added and stirred for 1 hour to obtain the varnish of resin composition E1.

[0195] In addition, in accordance with the ingredient amounts listed in Tables 1 to 3 and the method for preparing the varnish of Example E1, varnishes of other Examples E2 to E10 and Comparative Examples C1 to C6 were prepared.

[0196] 2. Prepreg (using 2116E-glass fiber cloth)

[0197] The resin compositions of the different examples (E1 to E10) and comparative examples (C1 to C6) listed in Tables 1 to 3 were added to a mixing tank in batches, mixed evenly, and stirred until completely dissolved into varnish. The resin compositions were then placed in an impregnation tank. Fiberglass cloth (e.g., E-fiberglass cloth of specification 2116) was passed through the impregnation tank to adhere the resin composition to the fiberglass cloth. The mixture was then heated at 120°C to 150°C to a semi-cured state (B-Stage) to obtain a semi-cured sheet (resin content approximately 52%).

[0198] 3. Copper foil substrate 1 (made of eight prepreg sheets laminated together)

[0199] Two 18-micron-thickness reverse-treat copper foils (RTF copper foils) and eight prepregs (using 2116E-glass fiber cloth) made from various resin compositions are prepared in batches. Each prepreg has a resin content of approximately 52%. The copper foils, eight prepregs, and copper foils are stacked in sequence and pressed under vacuum at 210°C for 2 hours to form each copper foil substrate 1. The eight stacked prepregs are cured (C-stage) to form an insulating layer between the two copper foils, with a resin content of approximately 52%.

[0200] 4. Copper foil substrate 2 (composed of six prepreg sheets laminated together)

[0201] Two 18-micron-thickness reverse-treat copper foils (RTF copper foils) and six prepregs (using 2116E-glass fiber cloth) made from various resin compositions are prepared in batches. Each prepreg has a resin content of approximately 52%. The copper foils, six prepregs, and copper foils are stacked in sequence and pressed under vacuum at 210°C for 2 hours to form each copper foil substrate 2. The six stacked prepregs are cured (C-stage) to form an insulating layer between the two copper foils, with a resin content of approximately 52%.

[0202] 5. Copper-free substrate 1 (made of eight prepreg sheets laminated together)

[0203] The copper foil substrate 1 is etched to remove the copper foil on both sides to obtain a copper-free substrate 1, which is made of eight prepreg sheets and has a resin content of about 52%.

[0204] 6. Copper-free substrate 2 (composed of six prepreg sheets laminated together)

[0205] The copper foil substrate 2 is etched to remove the copper foil on both sides to obtain a copper-free substrate 2, which is made of six prepreg sheets and has a resin content of about 52%.

[0206] The test methods and characteristic analysis items for the samples to be tested are described below.

[0207] 1. Glass transition temperature (DMA-Tg)

[0208] In the glass transition temperature test, the copper-free substrate 1 described above was selected as the test sample. Using a dynamic mechanical analyzer (DMA), following the method described in IPC-TM-650 2.4.24.4, the sample was heated at a rate of 2°C per minute, from 50°C to 400°C, and the glass transition temperature (unit: °C, denoted as DMA-Tg) was measured. A higher glass transition temperature is better, and a difference of 5°C or more between the glass transition temperatures of different test samples is considered significant (presenting significant technical difficulty).

[0209] For example, an article made using a resin composition containing a phosphorus-containing compound having the structure shown in formula (I) disclosed in this invention has a glass transition temperature greater than or equal to 245°C, for example, between 245°C and 269°C, or between 258°C and 269°C, as measured with reference to the method described in IPC-TM-650 2.4.24.4.

[0210] 2. Z-axis thermal expansion ratio (Z-PTE)

[0211] In the measurement of Z-axis thermal expansion coefficient, the aforementioned copper-free substrate 2 was selected as the test sample for thermomechanical analysis (TMA). The copper-free substrate 2 was cut into samples with a length and width of 10 mm. The samples were heated at a rate of 10 °C per minute, from 35 °C to 300 °C. The Z-axis thermal expansion coefficient (in %) of each test sample was measured within the temperature range of 50 °C to 260 °C, referring to the method described in IPC-TM-650 2.4.24.5. A lower Z-axis thermal expansion coefficient indicates better characteristics. Generally, a difference in Z-axis thermal expansion coefficient greater than or equal to 0.1% is considered significant (presenting significant technical difficulty).

[0212] For example, an article made using a resin composition containing a phosphorus-containing compound having the structure shown in formula (I) disclosed in this invention has a Z-axis thermal expansion coefficient of less than or equal to 1.45%, for example, between 0.95% and 1.45%, or between 0.95% and 1.21%, as measured with reference to the method described in IPC-TM-650 2.4.24.5.

[0213] 3. Heat resistance of T288

[0214] In the T288 heat resistance test, the aforementioned copper foil substrate 2 (6.5 mm × 6.5 mm) was selected as the test sample. Using a thermomechanical analyzer (TMA), at a constant temperature of 288°C, the measurements of each test sample were taken according to the method described in IPC-TM-650 2.4.24.1, and the time it took for the copper foil substrate to burst under heat was recorded. A longer bursting time indicates higher heat resistance of the copper foil substrate made using the resin composition. If the test time exceeds 60 minutes without bursting, it is marked ">60", indicating that the T288 heat resistance test can be performed for more than 60 minutes without bursting.

[0215] For example, an article made using a resin composition containing a phosphorus-containing compound having the structure shown in Formula (I) disclosed in this invention has a non-explosion time greater than or equal to 50 minutes, for example, greater than or equal to 60 minutes, for example, between 50 minutes and 100 minutes, or for example, between 50 minutes and 80 minutes, as measured by a thermomechanical analyzer with reference to the method described in IPC-TM-650 2.4.24.1.

[0216] 4. Flame retardancy

[0217] In the flame retardancy test, the copper-free substrate 1 mentioned above was selected as the test sample. Measurements were performed according to the method described in UL 94. The flame retardancy analysis results are expressed as V-0, V-1, and V-2 ratings, where V-0 has better flame retardancy than V-1, and V-1 has better flame retardancy than V-2.

[0218] For example, an article made using a resin composition containing a phosphorus-containing compound having the structure shown in Formula (I) disclosed in this invention has a flame retardancy rating of V-0 or V-1 when measured with reference to the method described in UL 94 specification, for example, a flame retardancy rating of V-0.

[0219] 5. Flame retardant migration

[0220] In the flame retardant migration test, two copper-free substrates 1 were selected as test samples. One substrate was not tin-immersed, while the other was tin-immersed according to the method described in IPC-TM-650 2.4.23. The copper-free substrate 1 was immersed in a tin bath at a temperature set to 288°C for 20 seconds, and then removed. The two copper-free substrates 1 were visually compared to each other to observe whether the surface of the tin-immersed substrate 1 was different from that of the untin-immersed substrate 1, such as whether it became brighter or whether there were foreign objects. If the surface became brighter or had foreign objects, a Fourier Transmission Infrared (FTIR) test was performed. The FTIR spectra of the substances appearing on the surface of the copper-free substrate 1 were then compared with those of the flame retardant used on the copper-free substrate 1. If they were similar, it could be confirmed that the flame retardant had migrated, and it was recorded as "Yes". If no abnormalities were observed on the surface of the copper-free substrate 1, it could be considered that the flame retardant had not migrated, and it was recorded as "No".

[0221] 6. Flame retardant detachment

[0222] In the flame retardant shedding test, the aforementioned copper-free substrate 1 was selected as the test sample. A 1.5 cm long sample of the copper-free substrate 1 was cut, and then subjected to various known slicing processes in the art, such as resin potting, grinding, cleaning, polishing, and gold plating, to produce qualified slices. The slices were then placed in an ultrasonic cleaner (ultrasonic power frequency set to 40 kHz) and subjected to ultrasonic vibration for 10 minutes before being removed. After drying, the slices were observed using a scanning electron microscope (SEM). The morphology of the resin layer in the sliced ​​sample could be clearly observed at magnifications from 500 to 2000. This invention uses a magnification of 2000 for sequential observation of the elongated samples. When voids were observed in the sample slice, such as... Figure 4 As shown, this can be confirmed as flame retardant detachment, denoted as "detachment". When no voids are observed in the sample slices, as... Figure 5 As shown, it can be confirmed that the flame retardant has not detached, and it is recorded as "none".

[0223] If the flame retardant in the substrate detaches under external forces, such as ultrasonic vibration, it can be assumed that the flame retardant will also detach during subsequent printed circuit board (PCB) processing. When external forces are applied, such as during drilling (specifically laser drilling, which involves both vibration and heat), if the flame retardant detaches, it will cause unevenness in the hole walls, leading to quality issues during electroplating and potentially affecting PCB reliability. Therefore, preventing flame retardant detachment is one of the most important quality requirements for the substrate.

[0224] 7. Bonding gap

[0225] In the crosslinking gap test, the copper-free substrate 1 mentioned above was selected as the test sample. A strip sample measuring 2.0 cm × 1.5 cm was cut from both the radial and weft directions of the test sample, and each strip was ultrasonically cleaned for 1 minute. After ultrasonic cleaning twice, the strip sample underwent various known slicing processes in the art, including resin potting, grinding, cleaning, polishing, and gold plating, to produce qualified slices. These slices were then observed using a scanning electron microscope (SEM). Using a magnification of 20,000, the presence of crosslinking gaps at the interface between the flame retardant and resin in the resin layer of the sliced ​​sample could be observed sequentially. When a crosslinking gap was observed at the interface between the flame retardant and resin in one of the sliced ​​samples, such as... Figure 6 and Figure 7 As shown, it can be confirmed that there are cross-linking gaps, for example... Figure 6 The strip-shaped cross-linking gaps shown in the black circle, or for example... Figure 7 The annular crosslinking gaps surrounding the flame retardant. The shape and width of the crosslinking gaps are not particularly limited; their presence is recorded as "present." When no crosslinking gaps are observed at the interface between the flame retardant and resin in two sliced ​​samples, such as... Figure 8 As shown, it can be confirmed that there are no cross-linking gaps, which is denoted as "none".

[0226] When cross-linking gaps exist at the interface between the flame retardant and the resin in the substrate, channels for ion migration may be formed, which may negatively affect the reliability of the subsequent PCB.

[0227] Based on the test results in Tables 1 to 3, the following phenomena can be observed.

[0228] By comparing Examples E2 and E5 and Comparative Example C1, it can be confirmed that the phosphorus-containing compound of the present invention having the structure shown in Formula (I) can achieve one or more of the following technical effects compared to FCX-210: increasing glass transition temperature, reducing Z-axis thermal expansion coefficient, improving T288 heat resistance, improving flame retardant migration, improving flame retardant shedding, and improving crosslinking gap.

[0229] By comparing Examples E2 and E5 and Comparative Example C3, it can be confirmed that the phosphorus-containing compound of the present invention having the structure shown in Formula (I) can achieve one or more of the following technical effects compared with Comparative Compound 1: increasing the glass transition temperature and reducing the Z-axis thermal expansion coefficient.

[0230] By comparing Examples E2 and E5 and Comparative Example C4, it can be confirmed that the phosphorus-containing compound of the present invention having the structure shown in Formula (I) can achieve one or more of the following technical effects compared with Comparative Compound 2: increasing glass transition temperature, reducing Z-axis thermal expansion coefficient, improving T288 heat resistance, improving flame retardant migration, improving flame retardant shedding, and improving crosslinking gap.

[0231] By comparing Examples E2 and E5 and Comparative Example C5, it can be confirmed that the phosphorus-containing compound of the present invention having the structure shown in Formula (I) can achieve one or more of the following technical effects compared with stilbene pentaerythritol diphosphite: increasing the glass transition temperature, reducing the Z-axis thermal expansion coefficient and improving the heat resistance of T288.

[0232] By comparing Examples E2 and E5 and Comparative Examples C2 or C6, it can be confirmed that the phosphorus-containing compounds of the present invention having the structure shown in Formula (I) can achieve one or more of the following technical effects compared to other phosphate ester flame retardants (such as PX-200 and allyl phosphate) that do not have a pentaerythritol spiroheterocycle: increasing the glass transition temperature, reducing the Z-axis thermal expansion coefficient, improving the heat resistance of T288, and improving flame retardant migration.

[0233] By comparing Examples E1 and E3 and Examples E9 and E10, it can be confirmed that if the amount of phosphorus-containing compound with the structure shown in Formula (I) is between 20 parts by weight and 70 parts by weight, compared with the amount range of 10 parts by weight or 80 parts by weight, it can achieve one or more of the following technical effects: increase the glass transition temperature, reduce the Z-axis thermal expansion coefficient, improve the heat resistance of T288 and improve the flame retardancy.

[0234] By comparing Examples E1-E10 with Comparative Examples C1-C6, it can be confirmed that articles made from phosphorus-containing compounds having the structure shown in Formula (I) of the present invention can achieve one, multiple, or all of the following technical effects: glass transition temperature greater than or equal to 245°C, Z-axis thermal expansion coefficient less than or equal to 1.45%, non-explosion time greater than or equal to 50 minutes, UL 94 flame retardancy rating of V-1 or V-0, no flame retardant migration, no flame retardant shedding, and no crosslinking gaps. Conversely, Comparative Examples C1-C6, which do not use the technical solution of the present invention, cannot simultaneously achieve the aforementioned technical effects.

[0235] The above embodiments are merely illustrative in nature and are not intended to limit the embodiments of the subject matter of the application or the application or use of such embodiments. In this document, the term "illustrative" means "as an example, illustration, or description." Any illustrative embodiment herein should not necessarily be interpreted as preferred or more advantageous than other embodiments.

[0236] Furthermore, although at least one exemplary embodiment or comparative example has been presented in the foregoing embodiments, it should be understood that numerous variations are possible with respect to the invention. It should also be understood that the embodiments described herein are not intended to limit the scope, use, or configuration of the claimed subject matter in any way. Rather, the foregoing embodiments will provide a simple guide for those skilled in the art to implement one or more of the described embodiments. Moreover, various changes can be made to the function and arrangement of the elements without departing from the scope defined by the claims, and the claims include known equivalents and all foreseeable equivalents at the time of filing of this patent application.

Claims

1. A phosphorus-containing compound having the structure shown in formula (I): Its features are, n is 0 or 1, and the Ar group represents a divalent aromatic hydrocarbon group.

2. The phosphorus-containing compound according to claim 1, characterized in that, The divalent aromatic hydrocarbon group includes benzoxyl, naphthyl, or biphenylxyl.

3. The phosphorus-containing compound according to claim 1, characterized in that, The divalent aromatic hydrocarbon group is unsubstituted.

4. The phosphorus-containing compound according to claim 1, characterized in that, The phosphorus-containing compound has the structure shown in formula (II):

5. The phosphorus-containing compound according to claim 1, characterized in that, The phosphorus-containing compound has the structure shown in formula (III):

6. The phosphorus-containing compound according to claim 1, characterized in that, The phosphorus content of the phosphorus-containing compound is between 9% and 15%.

7. A method for preparing a phosphorus-containing compound having the structure shown in formula (I) according to claim 1, characterized in that, The preparation method includes reacting a compound with the structure shown in formula (A) with a compound with the structure shown in formula (B) to obtain the phosphorus-containing compound having the structure shown in formula (I): Where X represents a hydroxyl or magnesium halide group, and Ar group represents a divalent aromatic hydrocarbon group.

8. The preparation method according to claim 7, characterized in that, The preparation method further includes reacting pentaerythritol with phosphorus oxychloride to prepare the compound with the structure shown in formula (A).

9. The preparation method according to claim 7, characterized in that, The compound with the structure shown in formula (A) and the compound with the structure shown in formula (B) react in the presence of an acid-binding agent.

10. The preparation method according to claim 7, characterized in that, The compound with the structure shown in formula (A) and the compound with the structure shown in formula (B) react in the absence of an acid-binding agent.

11. The preparation method according to claim 7, characterized in that, The compound with the structure shown in formula (B) is hydroxystyrene, styrene-based magnesium bromide, or styrene-based magnesium chloride.

12. A resin composition, characterized in that, The resin composition comprises 100 parts by weight of maleimide resin and 10 to 80 parts by weight of the phosphorus-containing compound according to claim 1.

13. The resin composition according to claim 12, characterized in that, The maleimide resin includes 4,4'-diphenylmethane bismaleimide, benzene maleimide oligomer, biphenyl aryl bismaleimide, indene-containing bismaleimide, m-phenylene bismaleimide, bisphenol A diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 2,3-dimethylbenzenemaleimide, 2,6-dimethylbenzenemaleimide, N-phenylmaleimide, and resins containing C5 to C64. 50 Maleimide resins or combinations thereof with aliphatic long-chain structures.

14. The resin composition according to claim 12, characterized in that, The resin composition comprises 100 parts by weight of maleimide resin and 20 to 70 parts by weight of the phosphorus-containing compound according to claim 1.

15. The resin composition according to claim 12, characterized in that, The resin composition further includes amine curing agents, inorganic fillers, curing accelerators, polymerization inhibitors, colorants, solvents, toughening agents, silane coupling agents, or combinations thereof.

16. An article made from the resin composition according to any one of claims 12 to 15, characterized in that, The products include prepregs, resin films, laminates, printed circuit boards, or cured insulators.

17. The article of claim 16, characterized in that, The article has one, more, or all of the following characteristics: The glass transition temperature measured by a dynamic mechanical analyzer according to the method described in IPC-TM-650 2.4.24.4 is greater than or equal to 245°C. The Z-axis thermal expansion coefficient measured by a thermomechanical analyzer according to the method described in IPC-TM-650 2.4.24.5 is less than or equal to 1.45%; The non-explosion time measured by a thermomechanical analyzer, as described in IPC-TM-650 2.4.24.1, is greater than or equal to 50 minutes. The flame retardancy rating obtained by measuring according to the method described in UL 94 is V-0 or V-1. Visual inspection confirmed that no flame retardant migration was found in the product; Scanning electron microscopy confirmed that no flame retardant had detached from the product. as well as Scanning electron microscopy confirmed that there were no cross-linking gaps in the product.

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