Bismaleimide compound and low dielectric resin composition containing the same

Abstract

A bismaleimide compound of formula (I) (wherein R1 is a divalent aliphatic radical and R2 is a divalent aromatic radical), and a resin composition containing the bismaleimide compound of formula (I) and having a low dielectric constant (Dk), a low dielectric dissipation factor (Df), and a high glass transition point (Tg).

Description

[Technical Field]

[0001] This disclosure relates to new bismaleimide compounds and resin compositions containing the compounds, their manufacturing processes, and their use in various applications, such as in the production of prepregs, laminates for printed wiring boards, molding compounds, and adhesives. The resin compositions provide cured products with high heat resistance, low water absorption, and excellent dielectric properties. Such advantageous properties are desirable in organic insulating materials for use in electronic devices such as communications equipment. [Background technology]

[0002] With the development of wireless networks and satellite communications, electronic products tend to require higher speeds, higher frequencies, and higher capacities for transmitting voice, video, and data. Furthermore, as these electronic products become thinner and smaller, electrical circuit boards tend to become more complex, denser, and multi-layered. In order to maintain high transmission speeds and signal integrity, the dielectric constant (D k ) and low dielectric loss (dielectric loss factor or dielectric dissipation factor (D f Materials with low dielectric constant (sometimes called dielectric loss), which results in low signal loss, are desired for printed circuit boards ("PCBs").

[0003] Polymer insulating materials are typically used as substrates for PCBs. PCB laminates are made from polymer insulating materials alone or by blending them with glass, fiber, nonwoven fabric, inorganic fillers, or similar materials. Epoxy resins have traditionally been used due to their low cost and high heat and chemical resistance upon curing. However, their relatively high dielectric constants and high dielectric loss tangents make it difficult to achieve the low dielectric loss tangents required for high-frequency signals. Polyphenylene ether (PPO) resins are also used in laminates due to their low dielectric constant and dissipation characteristics, but even lower dielectric loss factors and dissipation tangents are required for high-frequency signal applications in emerging electronic fields. Fluororesins, typically represented by polytetrafluoroethylene (PTFE), have low dielectric constants and dissipation tangents, but because they are thermoplastic resins, they tend to expand and contract significantly during molding and processing, making them difficult to handle.

[0004] Other types of resins are known, but they are unable to reach the low dielectric loss values ​​Df required in view of the requirements in high frequency signal transmission.

[0005] Bismaleimide compounds are well known in formulations for electronic materials.

[0006] Patent Document 1 discloses a thermosetting resin composition suitable for use in the electrical and electronics industry as an underfill and for potting. The thermosetting resin composition contains a thermosetting resin and a bismaleimide compound that is in a liquid form at 25°C.

[0007] US Patent No. 5,999,629 discloses imide-extended mono-, bis-, or polymaleimide compounds and their use for preparing thermosetting adhesive compositions useful for various purposes in the fabrication and assembly of semiconductor packages and microelectronic devices.

[0008] Patent Document 3 discloses aromatic polyimides with improved solubility in polar organic solvents and their use as adhesives, laminating resins (especially for printed circuit boards), fibers, coatings (for decorative and electrical purposes), films, enameled wire, and molding compounds.

[0009] However, prior art bismaleimide and aromatic polyimide compounds suffer from drawbacks due to limited solubility and moisture sensitivity.

[0010] There remains a need for resin compositions that can be used in electronic devices and that provide higher dielectric loss tangents and / or higher decomposition temperatures.

[0011] Specifically, there remains a need to provide curable bismaleimide compounds that provide resin compositions that are easily processable and have improved properties with respect to Df, thermomechanical properties, and moisture resistance. There is a need to improve high-speed signal transmission while reducing power and interference problems in electronic applications. This requires material compositions with improved dielectric properties while ensuring the thermomechanical properties and ease of manufacturing required for sustainable mass production of printed circuit boards and antennas.

[0012] It is an object of the present invention to overcome the aforementioned shortcomings of prior art resin compositions and to provide an improved polymeric insulating material which has satisfactory thermomechanical properties, moisture resistance, low dielectric characteristics, and is easily processable to address ever increasing high frequency signal transmission. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] European Patent Application Publication No. 3135722 [Patent Document 2] U.S. Patent No. 7,884,174 [Patent Document 3] U.S. Patent No. 3,856,752 Summary of the Invention

[0014] The present invention relates to a compound of the following formula (I): [ka] The present invention relates to a novel bismaleimide compound: During the ceremony, n is an integer, n is in the range of 1 to 10, m is an integer ranging from 1 to 10; each Q is independently a tetravalent radical selected from a C6-C50 hydrocarbon containing at least one aromatic group and optionally one or more heteroatoms selected from O, N, S, F, Cl, and Br; each R1 is independently a divalent radical selected from aliphatic and aromatic straight or branched chain C1 to C60 hydrocarbons optionally containing one or more NH2 groups or one or more NH bridges; Each R2 independently represents a C6 to C54 aromatic carbon atom optionally containing one or more halogen atoms. is a divalent radical selected from hydrogen, R is a divalent radical selected from R1 and R2; Each Y is independently H or CH3.

[0015] The present invention also relates to novel bismaleimide compounds obtainable by a process comprising the steps of: [ka] Step 1: reacting a dianhydride (IV) with a diamine of formula (II) and a diamine of formula (III) to obtain an amine-terminated extended imide (V); Step 2: Reacting the amine-terminated extended imide obtained from Step 1 with maleic anhydride compound (VI). During the ceremony, n, m, Q, R1, R2, R, and Y have the same definitions as in formula (I) above; An and Am represent the relative molar amounts of diamine H2N-R1-NH2 and diamine H2N-R2-NH2, respectively, introduced into the reaction medium relative to the amount of dianhydride.

[0016] The present invention also relates to a curable resin composition comprising at least the bismaleimide compound disclosed above and at least a thermosetting resin.

[0017] The present invention further relates to a process for manufacturing an article, comprising at least the following steps: -Step 1: preparing a curable resin composition comprising at least the bismaleimide compound disclosed above and a thermosetting resin; -Step 2: shaping the composition; -Step 3: Partially or fully curing the composition.

[0018] The present invention relates to an article (cured resin, resin composition) obtained by the method, which comprises the resin composition of the present disclosure. The present invention also relates to polymerizable compositions, including polymerizable cured resins, laminates, prepregs, electronic components, and single and multi-layer circuit boards.

[0019] The present invention also relates to the use of the resin composition as defined above in prepregs, metal clad laminates, printed circuit boards, light emitting diodes, electronic coatings, textiles, polymeric moulding compounds, medical moulding compounds and adhesives.

[0020] The bismaleimide compounds according to the present invention exhibit optimized performance between thermomechanics (glass transition) and low dielectric constant and loss at high frequencies, improved solubility in solvents (MEK (methyl ethyl ketone), cyclohexanone, toluene, xylene, etc.), together with processing characteristics suitable for formulation of electronic materials in improving dielectric and thermomechanical properties. DETAILED DESCRIPTION OF THE INVENTION

[0021] The present disclosure is generally directed to novel bismaleimide compounds and resin compositions derived from such novel bismaleimide compounds, which resins have a low dielectric constant (Dk), a low dissipation factor (Df), and excellent thermomechanical properties, such as high thermal stability, good processability, high peel strength, good moisture resistance, and / or a high glass transition temperature (Tg). In attempts to achieve the objectives of the present disclosure, it was surprisingly discovered that when resin compositions are made using the above-described bismaleimide compounds, significant reductions in Df can be achieved compared to resin compositions containing state-of-the-art resins, while still maintaining a high Tg. Overall, the novel resin compositions exhibit low Dk and low Df (typically Df<0.003) in the gigahertz range (e.g., 1-10 GHz), enabling them to meet stringent required industry standards in a variety of applications, such as prepregs, metal-clad laminates, printed circuit boards, light-emitting diodes, and electronic coatings. The novel resin compositions exhibit high thermomechanical performance (high Tg) and high solubility (>50 wt % in typical CCL (copper clad laminate) solvents (toluene, MEK, etc.).

[0022] The novel bismaleimide compounds and resin compositions may also be useful in chip design (integrated circuit (IC) packaging), coatings, chemical vapor deposition (CVD), and photochemistry. Furthermore, they may be used in the preparation of membranes, filters, and high-performance coatings, fiber-reinforced composites, and adhesives. The novel bismaleimide compounds may also be used as intermediates for radical and condensation polymerization.

[0023] The following terms shall have the following meanings:

[0024] The term "comprising" and its derivatives are not intended to exclude the presence of any additional component, step, or procedure, whether or not disclosed herein. For the avoidance of doubt, all compositions claimed herein through the use of the term "comprising" may include any additional additive, adjuvant, or compound, unless stated to the contrary. In contrast, the term "consisting essentially of," as used herein, excludes any other component, step, or procedure from the scope of any succeeding description, except those that are not essential to operability, and the term "consisting of," when used, excludes any component, step, or procedure not specifically described or listed. The term "or," unless otherwise stated, refers to the listed members individually or in any combination.

[0025] The articles "a" and "an" are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, "a cross-linking agent" is used in the context of "osslinker" refers to a crosslinker or multiple crosslinkers. The phrases "in one embodiment," "according to one embodiment," and the like generally mean that the particular feature, structure, or characteristic that follows the phrase is included in at least one embodiment of the present disclosure and may be included in multiple embodiments of the present disclosure. Importantly, such phrases do not necessarily refer to the same aspect. When a statement herein states that a component or feature "may," "can," "could," or "might" be included or have a characteristic, it does not require that the particular component or feature be included or have that characteristic.

[0026] The term "about," as used herein, allows for a degree of variation in a value or range, for example, it may be within 10%, within 5%, or within 1% of a stated value or stated range limit.

[0027] Values ​​expressed in range format should be interpreted in an open manner to include not only the numerical values ​​expressly recited as the limits of the range, but also all individual numerical values ​​or subranges subsumed within that range, as if each numerical value and subrange were expressly recited. For example, a range (such as 1 to 6) should be considered to specifically disclose subranges within that range (such as 1 to 3, 2 to 4, 3 to 6, etc.) as well as individual numbers (e.g., 1, 2, 3, 4, 5, and 6). This applies regardless of the breadth of the range.

[0028] The terms "preferred" and "preferably" refer to embodiments that may offer certain advantages, under certain circumstances, while other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the present disclosure.

[0029] The terms "in the range" or "within a range" (and similar descriptions) include the endpoints of the stated range.

[0030] Where a substituent is specified by its conventional chemical formula (written from left to right), such substituent is intended to equally encompass the chemically identical substituent that would be obtained by writing the structure from right to left, e.g., -CHO- is equivalent to -OCH-.

[0031] The term "optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes cases where the event or circumstance occurs and cases where it does not occur.

[0032] The term "alkyl" refers to a straight or branched chain hydrocarbyl radical having from 1 to 50 carbon atoms, and "substituted alkyl" refers to an alkyl further bearing one or more substituents selected from, but not limited to, hydroxy, alkoxy, mercapto, cycloalkyl, heterocyclic, aryl, heteroaryl, aryloxy, halogen, trifluoromethyl, cyano, nitro, nitrone, amino, amido, C(O)H, acyl, oxyacyl, carboxyl, carbamate, sulfonyl, sulfonamido, and sulfuryl.

[0033] The term "alkenyl" refers to a straight- or branched-chain hydrocarbyl radical having 2 to 50 carbon atoms and at least one carbon-carbon double bond.

[0034] The term "alkynyl" refers to an alkyl group having 2 to 50 carbon atoms and at least one carbon-carbon triple bond. refers to a straight or branched chain hydrocarbyl radical bearing a bond.

[0035] The term "aromatic" refers to a hydrocarbyl radical having 6 to 50 carbon atoms containing at least one ring (such as a benzene ring) with delocalized π electrons.

[0036] The term "aralkyl" refers to any monovalent radical derived from an alkyl radical by the replacement of one or more hydrogen atoms by an aryl group.

[0037] The terms "dissipation factor (Df)" and "loss tangent" are synonymous as used herein and refer to the amount of energy dissipated in an insulating material (i.e., electrical loss) when a voltage is applied to a circuit. Df represents the loss of a signal in a circuit.

[0038] The terms "dielectric constant (Dk)" and "permittivity" as used herein are synonymous and refer to a measure of the relative capacitance of an insulating material to that of air or vacuum. Permittivity determines the speed of electronic signals.

[0039] "Glass transition temperature" or "T g The term "temperature at which the amorphous domains of a polymer exhibit the characteristic properties of a glassy state (brittleness, rigidity, and rigidity) as used herein. The term also refers to the temperature at which a cured resin changes from a glassy state to a softer, more rubbery state.

[0040] Bismaleimide compounds

[0041] According to a first aspect, the present invention provides a compound of formula (I): [ka] The present invention relates to a novel bismaleimide compound: During the ceremony, n is an integer, n is in the range of 1 to 10, preferably n is in the range of 1 to 5; m is an integer, m is in the range of 1 to 10, preferably n is in the range of 1 to 5; each Q is independently a tetravalent radical selected from a C6-C50 hydrocarbon containing at least one aromatic group and optionally one or more heteroatoms selected from O, N, S, F, Cl, and Br; each R1 is independently a divalent radical selected from aliphatic and aromatic straight or branched chain C1 to C60 hydrocarbons optionally containing one or more NH2 groups and / or one or more NH bridges; Each R2 independently represents a C6 to C54 aromatic carbon atom optionally containing one or more halogen atoms. is a divalent radical selected from hydrogen, R is a divalent radical R or R, Y represents H or CH. Preferably, Y is H.

[0042] Q is a tetravalent radical present in the diamine H2N-R1-NH2 and the aromatic dianhydride reacted with the diamine H2N-R2-NH2.

[0043] Examples of radicals Q include the following structures: [ka] Q' is a divalent radical that may be selected from C1 to C38 hydrocarbons optionally containing one or more heteroatoms selected from O, N, S, F, Cl, Br. For example, Q' can be -CO-, -CO-NH-, -CO-O-, -O-CO-O-, -NH-CO-NH-, a divalent C1-C40 alkyl radical, a divalent C1-C40 alkenyl radical, or a divalent C1-C40 alkynyl radical, where the alkyl radical, alkenyl radical, or alkynyl radical optionally includes one or more -O- bridges, one or more -NH- bridges, one or more substituents selected from -OH, NH2, COOH, CONH2, -SH, -SO3H, and halogen atoms.

[0044] According to a particularly preferred embodiment, Q is selected from the following radicals: [ka]

[0045] Each R1 is independently a divalent radical selected from aliphatic and aromatic straight or branched chain C1-C60 hydrocarbyls, optionally containing one or more NH2 groups, one or more NH bridges. Preferably, each R1 is independently a divalent radical selected from C1-C60 alkyl, C2-C60 alkenyl, C2-C60 alkynyl, and C6-C60 aralkyl, optionally containing one or more NH2 groups, one or more NH bridges.

[0046] Each R1 can independently be straight or branched chain.

[0047] Advantageously, each R1 is independently selected from C1 to C60 alkyl, alkenyl, or aralkyl, optionally containing one or more NH2 groups, one or more NH bridges, and preferably from C12 to C60 alkyl, alkenyl, or aralkyl, optionally containing one or more NH2 groups, one or more NH bridges.

[0048] More advantageously, each R1 is independently selected from dimeric and trimeric hydrocarbon groups having a total number of C atoms between 12 and 60, and mixtures thereof.

[0049] Advantageously, R1 is chosen from linear, branched or cyclic alkyl or alkenyl or aromatic hydrocarbons having a total number of C atoms between 12 and 60, and mixtures thereof.

[0050] Each R2 is a divalent radical independently selected from aromatic C6 to C54 hydrocarbons.

[0051] Preferably, R2 is an aromatic C6-C54 divalent radical containing a phenylindane group.

[0052] Advantageously, R2 is of formula (IIIA) [ka] is selected from the divalent radicals During the ceremony, Y1 and Y2 independently represent H or C1-C5 alkyl; Each of Y3 and Y4 independently represents H, halogen, or C1-C4 alkyl. Y3 and / or Y4, when it is halogen, is preferably Cl. Preferably, in formula (IIIA), Y3 and Y4 are all H. Preferably, in formula (IIIA), Y1, Y2 independently represent H or a methyl group. According to one embodiment, Y1 and Y2 represent CH3. Preferably, in formula (IIIA), the radical substituents are located at the 5' or 6' position and the 4' position.

[0053] Preparation of bismaleimide compounds

[0054] The present invention also relates to novel bismaleimide compounds obtainable by a process comprising the steps of: [ka] Step 1: reacting a dianhydride (IV) with a diamine of formula (II) and a diamine of formula (III) to obtain an amine-terminated extended imide (V); Step 2: Reacting the amine-terminated extended imide (V) obtained from Step 1 with a maleic anhydride compound (VI). During the ceremony, n, m, Q, R1, R2, R, and Y have the same definitions and preferred embodiments as in formula (I) above; An and Am represent the relative molar amounts of diamine H2N-R1-NH2 (II) and diamine H2N-R2-NH2 (III), respectively, introduced into the reaction medium relative to the amount of dianhydride (IV).

[0055] Examples of aromatic dianhydrides (IV) include pyromellitic dianhydride; 1,4,5,8-naphthalenetetracarboxylic dianhydride; 2,3,6,7-naphthalenetetracarboxylic dianhydride; 1,2,4,5-naphthalenetetracarboxylic dianhydride; 1,2,5,6-naphthalenetetracarboxylic dianhydride; benzene-1,2,3,4-tetracarboxylic dianhydride; pyrazine-2,3,5,6-tetracarboxylic dianhydride; thiophene-2,3,4,5-tetracarboxylic dianhydride; and 3,4,9,10-perylenenetetracarboxylic dianhydride. ;2,3,9,10-Perylenetetracarboxylic dianhydride;2,6-Dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride;2,7-Dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride;2,3,6,7-Tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride;Phenanthrene-1,8,9,10-tetracarboxylic dianhydride;3,3',4,4'-Benzophenonetetracarboxylic dianhydride;2,2',3,3'-Benzophenonetetracarboxylic dianhydride;3,3',4,4'-Biphenyltetracarboxylic dianhydride;2,2',3,3'-Biphenyltetracarboxylic dianhydride 4,4'-Oxydiphthalic anhydride; 3,3'-oxydiphthalic anhydride; 4,4'-isopropylidenediphthalic anhydride; 3,3'-isopropylidenediphthalic anhydride; 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride; 4,4'-sulfonyldiphthalic anhydride; 4,4'-methylenediphthalic anhydride; 4,4'-thiodiphthalic anhydride; 4,4'-ethylidenediphthalic anhydride; 2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride; 4,4'-bisphenol A diphthalic anhydride; ethylene glycol bis(trimellitic anhydride); and hydroquinone diphthalic anhydride.

[0056] According to a particularly preferred embodiment, the aromatic dianhydride (IV) is pyromellitic dianhydride or 3,3',4,4'-benzophenonetetracarboxylic dianhydride.

[0057] Amines of formula (II) are commercially available. Examples of diamines (II) NH2-R1-NH2 that can be used in accordance with the present invention include 1,10-diaminodecane; 1,12-diaminododecane; 1,18-diamino-6,8-dialkylene; dimeric diamines like C36-alkylenediamine; trimer amines like C54 trimer amine; 1,2-diamino-2-methylpropane; 1,2-diaminocyclohexane; 1,2-diaminopropane; 1,3-diaminopropane; 1,4-diaminobutane; 1,5-diaminopentane; 1,7-diaminoheptane; 1,8-diaminomenthane; 1,8-diaminooctane; 1,9-diaminononane; 3,3'-diamino-N-methyldipropylamine; 1,3-diaminopentane; 1,3-bisaminomethylcyclohexane; polyoxyalkylenediamines (e.g., Jeffamine from Huntsman, D-230, D400, D-2000, and D-4000 products; 1,3-cyclohexanebis(methylamine); bis(4-amino-3-methylcyclohexyl)methane; 1,2-bis(2-aminoethoxy)ethane; 3(4),8(9)-bis(aminomethyl)tricyclo(5.2.1.0<2,6>)decane. Examples of amines include the mixtures of amines commercialized by Croda under the reference names Priamine 1075 (mainly dimeric amines) or Priamine 1071 (containing a mixture of dimeric amine C36 and trimeric amine C54). Other examples of amines from which R1 groups can be derived are amines derived from dimerized fatty acids, as illustrated in the following scheme: [ka]

[0058] Preferably, the diamine (II) NH2-R1-NH2 is selected from aliphatic C12-C60 dimeric diamines, C12-C60 trimer triamines, and mixtures thereof.

[0059] Examples of aromatic diamines (III) NH2-R2-NH2 that can be used in accordance with the present invention include DAPI (4',5-6-diamino-1,3,3-trimethyl-1-phenylindane); 9,10-diaminophenanthrene; 4,4'-diaminooctafluorobiphenyl; 3,5-diaminobenzoic acid; 3,7-diamino-2-methoxyfluorene; 4,4'-diaminobenzophenone; 3,4-diaminobenzophenone; 3,4-diaminotoluene; 2,6-diaminoanthraquinone; 2,6-diaminotoluene; 2,3- Diaminotoluene;1,8-Diaminonaphthalene;2,4-Diaminotoluene;2,5-Diaminotoluene;1,4-Diaminoanthraquinone;1,5-Diaminoanthraquinone;1,5-Diaminonaphthalene;1,2-Diaminoanthraquinone;2,4-Cumenediamine;1,3-Bisaminomethylbenzene;2-Chloro-1,4-diaminobenzene;1,4-Diamino-2,5-dichlorobenzene;1,4-Diamino-2,5-dimethylbenzene;4,4'-Diamino-2,2'-bistrifluoromethylbiphenyl;Bis(amino) Bis(4-amino-3,5-dimethylphenyl)ethane;Bis(4-amino-3,5-diethylphenyl)methane;Bis(4-amino-3-ethyldiaminofluorene;Diaminobenzoic acid;2,3-Diaminonaphthalene;2,3-Diaminophenol;-5-methylphenyl)methane;Bis(4-amino-3-methylphenyl)methane;Bis(4-amino-3-ethylphenyl)methane;4,4'-Diaminophenyl sulfone;3,3'-Diaminophenyl sulfone;2,2-Bis(4,-(4-aminophenyl)methane) 4,4'-Diaminophenoxy)phenyl) sulfone;2,2-Bis(4-(3-aminophenoxy)phenyl) sulfone;4,4'-Oxydianiline;4,4'-Diaminodiphenyl sulfide;3,4'-Oxydianiline;2,2-Bis(4-(4-aminophenoxy)phenyl)propane;1,3-Bis(4-aminophenoxy)benzene;4,4'-Bis(4-aminophenoxy)biphenyl;4,4'-Diamino-3,3'-dihydroxybiphenyl;4,4'-Diamino-3,3'-dimethylbiphenyl;4,4'-Diamino-3, Examples of suitable amines include 3'-dimethoxybiphenyl; bisaniline M; bisaniline P; 9,9-bis(4-aminophenyl)fluorene; o-tolidine sulfone; methylenebis(anthranilic acid); 1,3-bis(4-aminophenoxy)-2,2-dimethylpropane; 1,3-bis(4-aminophenoxy)propane; 1,4-bis(4-aminophenoxy)butane; 1,5-bis(4-aminophenoxy)butane; 2,3,5,6-tetramethyl-1,4-phenylenediamine; 3,3',5,5'-tetramethylbenzidine; 4,4'-diaminobenzanilide; 2,2-bis(4-aminophenyl)hexafluoropropane; m-xylylenediamine; and p-xylylenediamine.

[0060] Some phenylindanamines are commercially available. Others may be prepared by the methods disclosed in US 3,856,752, the contents of which are incorporated herein by reference.

[0061] Preferably, the diamine (III) NH2-R2-NH2 is selected from DAPI (4',5-6-diamino-1,3,3-trimethyl-1-phenylindane).

[0062] Preferably, according to the present invention, the ratio of the sum of amines (Am+An) to dianhydride compounds is in the range of about 5:1 to about 1.05:1, more preferably in the range of about 3:1 to about 1.1:1, even more preferably in the range of about 2:1 to about 1.2:1, and in a preferred embodiment, about 1.5:1.

[0063] Preferably, according to the invention, the molar ratio Am / An of aromatic amine(s) to aliphatic amine(s) is in the range of about 20:1 to about 1:1, more preferably in the range of about 10:1 to about 2:1, even more preferably in the range of about 5:1 to about 3:1, and advantageously about 4:1.

[0064] Preferably, the maleic anhydride compound (VI) is maleic anhydride.

[0065] The amount of maleic anhydride compound is selected to provide a product end-capped with maleimide groups on both ends.

[0066] According to a preferred embodiment, the first step of the process for the preparation of the bismaleimide compounds of formula (I) proceeds in two substeps: Substep 1a: reacting the dianhydride (IV) with an aliphatic diamine of formula H2N-R1-NH2 (II), Sub-step 1b: Reacting the product obtained from sub-step 1a with an aromatic diamine H2N-R2-NH2 to obtain an amine-terminated extended imide (V).

[0067] Advantageously, the process for the preparation of the bismaleimide compounds of formula (I) is carried out in one pot without isolating intermediate compounds such as the amine-terminated extended imide (V).

[0068] The reaction mixture comprises a mixture of compounds of formula (I), where R1, R2, Y, n, and m can vary depending on the parameters selected for carrying out the reaction. Those skilled in the art are knowledgeable in the preparation of bismaleimide compounds and understand that other products may be present in the reaction mixture in addition to the compounds of formula (I) and intermediate compounds according to the present invention. For example, the mixture may comprise some compounds of formula (I) where n=0 and some compounds of formula (I) where m=0.

[0069] Curable resin composition

[0070] The bismaleimide compound of formula (I) and / or the bismaleimide compound obtained by the method disclosed above advantageously represents from about 20 to about 99 wt %, more preferably from about 30 to about 98 wt %, of the total weight of the resin composition.

[0071] In addition to the bismaleimide compound of formula (I) and / or the bismaleimide compound obtained from the method disclosed above, the resin composition advantageously comprises a co-curing agent or a thermosetting resin.

[0072] The use of a co-curing agent in the resin composition makes it possible to lower the curing temperature or accelerate the curing reaction. According to a particularly preferred embodiment, the composition of the present invention comprises at least one co-curing agent or thermosetting resin, which can be selected from, for example, polyphenylene ether derivatives, maleimide, styrene, divinylbenzene, trivinylcyclohexane, trialkenyl isocyanurate compounds, and mixtures thereof.

[0073] Advantageously, the co-curing agent is selected from trialkenyl isocyanurate compounds, such as triallyl isocyanurate (TAIC).

[0074] The amount of co-curing agent used will vary depending on the content of unsaturated groups in the curable resin composition, the selection of the particular co-curing agent, its half-life temperature, and the stability required. In one embodiment, the curable resin composition of the present invention may contain co-curing agents and mixtures thereof in an amount ranging from about 1% to about 50% by weight, or from about 2% to about 20% by weight, based on the total weight of the composition plus additives.

[0075] Additional ingredients

[0076] Before curing, the curable resin composition can be mixed with a variety of additives selected according to the intended use and expected properties. Such additives are detailed below in a non-limiting manner. In this section, percentages are expressed in terms of the weight of the additional compound relative to the total weight of the resin composition plus the additive.

[0077] The resin composition of the present disclosure can be cured by simple heating, but to improve curing efficiency, a curing catalyst that generates free radical species can be added. Examples of such curing catalysts include, but are not limited to, benzoin-type compounds (such as benzoin and benzoin methyl), acetophenone-type compounds (such as acetophenone and 2,2-dimethoxy-2-phenylacetophenone and the like); thioxanthone-type compounds (such as thioxanthone and 2,4-diethylthioxanthone), bisazide compounds (such as 4,4'-diazidochalcone, 2,6-bis(4-azidobenzal)cyclohexanone, and 4,4'-diazidobenzophenone), azo compounds (such as azobisisobutyronitrile, 2,2-azobispropane, m.m'-azoxy-styrene, and hydrazones), organic peroxides (such as 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, and dicumyl peroxide).

[0078] The resin composition may contain the curing catalyst in an amount of about 0.1% to 10% by weight, or about 0.3% to 7% by weight, or about 0.5% to 5% by weight, or about 1% to 3% by weight, where the weight percent is based on the total weight of the resin composition.

[0079] In another embodiment, a polymerization inhibitor may be optionally added to the resin composition to enhance storage stability. Examples include quinones and aromatic diols (such as hydroquinone, p-benzoquinone, chloranil, trimethylquinone, and 4-t-butylpyrocatechol). When present, the resin composition may contain about 0.0005% to 5% by weight of a polymerization inhibitor, the weight percent being based on the total weight of the resin composition.

[0080] In another embodiment, the resin composition may optionally include an inorganic filler, an organic filler, or a mixture thereof. The fillers contemplated for use in the practice of the present disclosure may be in any of a variety of forms, such as angular, platelet-like, spherical, amorphous, sintered, fired, powdered, flaked, crystalline, ground, crushed, pulverized, and the like, or a mixture of any two or more thereof. Currently preferred particulate fillers contemplated for use herein are substantially spherical.

[0081] Such fillers may optionally be thermally conductive. Both powder and flake forms of fillers may be used in the resin compositions of the present disclosure. Fillers having a wide range of particle sizes may also be used in the practice of the present disclosure. Particle sizes ranging from about 500 nm up to about 300 microns may be used, with particle sizes less than about 100 microns being preferred, and particle sizes within the range of about 5 up to about 75 microns being particularly preferred.

[0082] A wide variety of fillers can be used in the practice of the present disclosure, including, for example, soft fillers (e.g., uncalcined talc), naturally occurring minerals (e.g., aluminum nitride, boron nitride, silicon carbide, diamond, graphite, beryllium oxide, magnesia, silica, alumina, aluminum silicate, and the like), calcined naturally occurring minerals (e.g., enstatite), synthetic calcined minerals (e.g., cordierite), treated fillers (e.g., silane-treated minerals), organic polymers (e.g., polytetrafluoroethylene), hollow spheres, microspheres, powdered polymeric materials, and the like.

[0083] Examples of fillers include talc, mica, calcium carbonate, calcium sulfate, aluminum nitride, boron nitride, silicon carbide, diamond, graphite, beryllium oxide, magnesia, silica, alumina, TiO2, aluminum silicate, aluminum-zirconium-silicate, cordierite, silane-treated minerals, polytetrafluoroethylene, polyphenylene sulfide, and the like.

[0084] Thermally conductive fillers contemplated for optional use in the practice of the present disclosure include, for example, aluminum nitride, boron nitride, silicon carbide, diamond, graphite, beryllium oxide, magnesia, silica, alumina, zirconium silicate, and the like. Preferably, the particle size of such fillers is about 20 microns. If aluminum nitride is used as the filler, it is preferable to passivate it via an adherent conformal coating (e.g., silica or the like).

[0085] When filler is present, the resin composition may contain up to about 75 wt. %, or up to about 50 wt. %, or up to about 25 wt. %, or up to about 10 wt. % filler, where the wt. % is based on the total weight of the resin composition.

[0086] In another embodiment, the resin composition may be dissolved or dispersed in an organic solvent to form a resin composition varnish. The amount of solvent is not limited, but is typically sufficient to achieve a solids concentration in the solvent of at least about 30% to about 90% by weight, or about 50% to 85% by weight, or about 55% to 75% by weight.

[0087] The organic solvent is not particularly limited and may be a ketone, an aromatic hydrocarbon, an ester, an amide, or an alcohol. More specifically, examples of the organic solvent that can be used include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, and xylene. , methoxyethyl acetate, ethoxyethyl acetate, butoxyethyl acetate, ethyl acetate, N-methylpyrrolidone formamide, N-methylformamide, N,N-dimethylacetamide, methanol, ethanol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, propylene glycol monopropyl ether, dipropylene glycol monopropyl ether, and mixtures thereof.

[0088] The resin compositions of the present disclosure may optionally include one or more additives, such as softeners, antioxidants, dyes, pigments, surfactants, defoamers, silane coupling agents, dispersants, thixotropic agents, processing aids, flow improvers, cure accelerators, strength enhancers, toughening agents, UV protectants (particularly UV blocking dyes suitable for enabling automated optical inspection (AOI) of circuits), flame retardants, and the like, as well as mixtures of any two or more thereof.

[0089] Softeners (also called plasticizers) contemplated for use in certain embodiments of the present invention include compounds that reduce the brittleness of the formulation (e.g., branched polyalkanes or polysiloxanes, which lower the glass transition temperature of the composition). Such plasticizers include, for example, polyethers, polyesters, polythiols, polysulfides, and polybutadienes (such as those sold under the brand names PolyBD® and RICON®). When used, plasticizers are typically present in a range of about 0.5% up to about 30% by weight of the resin composition.

[0090] Antioxidants contemplated for use in the practice of the present invention include hindered phenols (e.g., BHT (butylated hydroxytoluene), BHA (butylated hydroxyanisole), TBHQ (tertiary-butylhydroquinone), 2,2′-methylenebis(6-tertiarybutyl-p-cresol), and the like), hindered amines (e.g., diphenylamine, N,N′-bis(1,4-dimethylpentyl-p-phenylenediamine, N-(4-anilinophenyl)methacrylamide, 4,4′-bis(α,α-dimethylbenzyl)diphenylamine, and the like), phosphites, and the like. If used, the amount of antioxidant typically falls within the range of about 100 up to 2000 ppm by weight of the resin composition.

[0091] Dyes contemplated for use in certain embodiments of the present disclosure include nigrosine, Orasol blue GN, phthalocyanines, fluorescent dyes (e.g., Fluoral green gold dye, and the like), and the like. When used, organic dyes provide contrast in relatively small amounts (i.e., less than about 0.2% by weight).

[0092] Pigments contemplated for use in certain embodiments of the present disclosure include any particulate material added solely for the purpose of imparting color to the formulation, such as carbon black, metal oxides (e.g., Fe2O3, titanium dioxide), and the like. When present, pigments are typically present in a range of about 0.5% up to about 5% by weight based on the weight of the resin composition.

[0093] Toughening agents contemplated for use in the practice of the present disclosure are materials that increase the impact resistance of various articles. Examples of toughening agents include synthetic rubber containing compounds such as Hypro, Hypox, and the like.

[0094] UV protection agents contemplated for use in certain embodiments of the present invention include those capable of blocking incident ultraviolet light ( UV protectants include compounds that absorb UV (ultraviolet rays) and thereby reduce the negative effects of such exposure on the resin or polymer system to which they are added. Examples of UV protectants include bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, silicones, powdered metal compounds, hindered amines (known in the art as "HALS"), and the like.

[0095] Antifoaming agents contemplated for use in certain embodiments of the present invention include materials that inhibit the formation of foam or bubbles when the solution is agitated or sheared during processing. Examples of antifoaming agents contemplated for use herein include n-butyl alcohol, silicon-containing antifoaming agents, and the like.

[0096] Examples of silane coupling agents contemplated for use in the practice of the present invention include materials that form crosslinks between inorganic surfaces and reactive polymeric components, including materials such as epoxy silanes, amino silanes, and the like.

[0097] Examples of thixotropic agents contemplated for use in the practice of the present invention include materials that impart to a liquid the property of enhanced flow when shear is applied, including materials such as high surface area fillers (e.g., fumed silica) having particle sizes in the range of about 2-3 microns or even submicron in size.

[0098] The resin composition of the present disclosure can be prepared by appropriately mixing the above components, and then kneading or mixing them as needed using a kneading device (such as a three-roll mill, ball mill, bead mill, or sand mill) or a stirring device (such as a high-speed rotary mixer, super mixer, or planetary mixer). Furthermore, a resin composition varnish can be prepared as described above by adding one or a mixture of the organic solvents described above. The amount of solvent is not limited, but is typically sufficient to achieve a solids concentration in the solvent of at least 30% to 90% by weight, or about 50% to 85% by weight, or about 55% to 75% by weight.

[0099] hardening

[0100] According to yet another embodiment of the present disclosure, there is provided an article comprising a partially or fully cured layer of the above-described resin composition. According to one particularly preferred embodiment, there is provided an article comprising a partially or fully cured layer of the above-described resin composition on a substrate.

[0101] When the resin is cured by heat, the curing temperature varies depending on the resin composition and the type and amount of curing agent used. Generally, the curing temperature is in the range of about 20°C to about 250°C, and preferably in the range of about 50°C to about 250°C.

[0102] Purpose

[0103] According to yet another embodiment of the present disclosure, an article is provided comprising a partially or fully cured layer of the above-described composition, preferably in association with a substrate.

[0104] The cured articles may be suitable for use in electronic equipment (such as communications equipment) and as organic insulating materials, particularly for use in the manufacture of high frequency laminates.

[0105] The selection of diamines (II) and (III), dianhydride (IV), their ratios, and the selection of parameters that result in the bismaleimide compound of formula (I) results in a resin composition with improved processing, dielectric, and thermomechanical properties, and reduced water sensitivity.

[0106] The present invention relates to a method for manufacturing an article, the method comprising at least the steps of preparing the curable resin composition disclosed above, molding the composition, and curing the composition.

[0107] Molding involves structuring the composition by forcing it into a desired shape and / or by associating it with another material, such as a support material (also called a substrate or support article). Molding can include dissolving the resin composition in a solvent. Below, several variants of the method according to the invention for producing an article are detailed.

[0108] The present invention further relates to a process for manufacturing an article (eg, a high frequency laminate) comprising at least the following steps: - Step 1: Preparing the curable resin composition disclosed above; - Step 2: Dissolving the curable resin composition of step 1 in a solvent to form a varnish and applying the varnish to a support article. Step 3: Curing the composition.

[0109] Applying the varnish to the support article can be carried out by any method known to those skilled in the art, such as, for example, brushing the curable resin composition onto the support article, spraying the curable resin composition onto the support article, or spin-coating the curable resin composition onto the support article.

[0110] The present invention further relates to a process for manufacturing an article, in particular a high frequency laminate, comprising at least the following steps: - Step 1: Preparing the curable resin composition disclosed above; Step 2: Impregnating the support material, in particular the fibrous material, with the composition of step 1. Step 3: Curing the composition.

[0111] Impregnation of the textile material with the curable resin composition can be carried out by any method known to those skilled in the art, such as, for example, immersing the textile material in a solution of the curable resin composition, spraying the curable resin composition onto the textile material, or spin-coating the curable resin composition onto the textile material. Such methods may require dissolving the curable resin composition in a solvent to form a varnish.

[0112] The present invention further relates to a process for manufacturing an article, comprising at least the following steps: - Step 1: Preparing the curable resin composition disclosed above; Step 2: introducing the composition of step 1 into a mold; - Step 3: Allowing the composition to partially or completely cure.

[0113] The present invention also relates to an article obtainable by a process comprising at least the step of curing a composition according to the invention.

[0114] The compositions of the present invention can provide articles that can be used in a variety of applications, such as prepregs, metal clad laminates (e.g., copper clad laminates), printed circuit boards, light emitting diodes, and electronic coatings.

[0115] In particular, the present invention relates to a prepreg obtainable by impregnating a fibrous material with the curable resin composition according to the present invention and curing the resin.

[0116] The present invention also provides a laminate sheet, which can be used as a high-frequency laminate, and which comprises a prepreg as defined above and a layer of conductive material disposed on at least one surface of the prepreg.

[0117] The present invention is also directed to a printed wiring board obtained by forming a conductive pattern on the surface of the laminate sheet as defined herein above.

[0118] As will be readily appreciated by those skilled in the art, a variety of substrates are suitable for use in the practice of the present disclosure, such as polyesters, liquid crystal polymers, polyamides (e.g., aramids), polyimides, polyamide-imides, polyolefins, polyphenylene oxides, polyphenylene sulfides, polybenzoxazines, conductive materials (e.g., conductive metals), and the like, as well as combinations of any two or more thereof. When conductive metal substrates are used, materials such as silver, nickel, gold, cobalt, copper, aluminum, alloys of such metals, and the like are contemplated for use herein.

[0119] According to yet another embodiment of the present disclosure, there is provided a method of making the above-described article (i.e., an article comprising a composition according to the present disclosure on a substrate / support article), the method comprising applying the resin composition to the substrate and removing substantially all organic solvent therefrom, if organic solvent is optionally used to facilitate such application. The resin composition may be applied to the substrate by dipping, impregnation, spraying, and the like.

[0120] According to yet another embodiment of the present disclosure, there is provided a prepreg obtained by impregnating a porous substrate with a resin composition according to the present disclosure, and, if an organic solvent is optionally used to facilitate such impregnation, subjecting the resulting impregnated substrate to conditions suitable for removing substantially all of the organic solvent therefrom.

[0121] As will be readily apparent to those skilled in the art, a variety of porous substrates can be used to prepare the prepregs of the present invention. The porous substrate can be a woven or nonwoven fabric. The thickness of such a substrate is not particularly limited and can be, for example, in the range of about 0.01 mm to 0.3 mm.

[0122] Examples of porous substrates include, but are not limited to, woven glass, nonwoven glass, woven aramid fiber, nonwoven aramid fiber, woven liquid crystal polymer fiber, nonwoven liquid crystal polymer fiber, woven synthetic polymer fiber, nonwoven synthetic polymer fiber, randomly distributed fiber reinforcement, expanded polytetrafluoroethylene (PTFE) structure, and any combination of two or more thereof. Specifically, materials contemplated for use as porous substrates may include, but are not limited to, fiberglass, quartz, polyester fiber, polyamide fiber, polyphenylene sulfide fiber, polyetherimide fiber, cyclic olefin copolymer fiber, polyalkylene fiber, liquid crystal polymer, poly(p-phenylene-2,6-benzobisoxazole), copolymer of polytetrafluoroethylene and perfluoromethylvinylether (MFA), and any combination of two or more thereof.

[0123] According to yet another embodiment of the present disclosure, there is provided a laminated sheet obtained by layering and molding a predetermined number of sheets of the above prepreg.

[0124] Laminate sheets according to the present disclosure have many particularly advantageous properties, such as, for example, low dielectric constants, low dielectric loss tangents, high pyrolysis temperatures, and the like. The laminated sheets according to the present disclosure have a nominal dielectric constant of ≦4.0, a dissipation factor at 10 GHz of ≦0.004, and a glass transition temperature of at least 100°C, or better, at least 150°C, and better, at least 200°C.

[0125] In one aspect of the present disclosure, the laminated sheets described herein may optionally further comprise one or more conductive layers. Such optional conductive layers may be selected from the group consisting of metal foils, metal plates, conductive polymer layers, and the like. In one embodiment, the metal may be copper, silver, nickel, gold, cobalt, aluminum, and alloys of such metals.

[0126] In another embodiment, a method for forming a laminate sheet is provided. The method includes contacting a porous substrate with a varnish bath containing the resin composition of the present disclosure dissolved in a solvent or mixture of solvents and intimately mixed therein. The contacting is carried out under conditions such that the porous substrate is coated with the resin composition. The coated porous substrate is then passed through a heated zone at a temperature sufficient to evaporate the solvent but below a temperature such that significant cure of the resin composition occurs during the residence time in the heated zone to form a prepreg.

[0127] The porous substrate has a residence time in the bath of about 1 second to about 300 seconds, more preferably about 1 second to about 120 seconds, and most preferably about 1 second to about 30 seconds. The temperature of such a bath is preferably about 0°C to about 100°C, more preferably about 10°C to about 40°C, and most preferably about 15°C to about 30°C. The residence time of the coated porous substrate in the heating zone is about 0.1 minutes to about 15 minutes, more preferably about 0.5 minutes to about 10 minutes, and most preferably about 1 minute to about 5 minutes.

[0128] The temperature in such zones is sufficient to volatilize any remaining solvent, but not so high as to result in complete cure of the components during the residence time. Preferred temperatures in such zones are from about 80°C to about 250°C, more preferably from about 100°C to about 225°C, and most preferably from about 150°C to about 210°C. Preferably, in the heated zone, there is a means for removing the solvent by passing an inert gas through the oven or by applying a slight vacuum to the oven. In many embodiments, the coated substrate is exposed to multiple zones of increasing temperature. The first zone is designed to allow the solvent to volatilize and be removed. Subsequent zones are designed to cause a partial cure of the resin composition (B-stage).

[0129] One or more sheets of prepreg are preferably processed into a laminate, optionally with one or more sheets of conductive material (such as copper). In such further processing, one or more segments or portions of the coated porous substrate are contacted with each other and / or with a conductive material. The contacted portions are then exposed to high pressure and temperature sufficient to cure the components, and the resin on adjacent portions reacts to form a continuous resin matrix between the porous substrates. Prior to curing, the portions can be cut and laminated, or folded and laminated to a desired shape and thickness. The pressure used can be anywhere from about 1 psi to about 1000 psi, with about 10 psi to about 800 psi being preferred. The temperature used to cure the resin composition in the portion or laminate depends on the specific residence time, pressure used, and components used. Preferred temperatures that can be used are about 100°C and about 250°C, more preferably about 120°C to about 220°C, and most preferably about 170°C to about 200°C. The residence time is preferably 10 to 120 minutes, more preferably about 20 to about 90 minutes.

[0130] In one embodiment, the process is a continuous process in which the porous substrate is removed from the oven, properly trimmed to the desired shape and thickness, and compressed at very high temperatures for a short period of time, specifically, temperatures of about 180° C. for a time period of about 1 minute to about 10 minutes and about 2 minutes to about 5 minutes. The preferred temperature range is from about 190°C to about 210°C, and more preferably from about 190°C to about 210°C. Such high speed compression allows for more efficient utilization of processing equipment. In such embodiments, the preferred reinforcing material is a glass fiber mesh or woven fabric.

[0131] In some embodiments, it may be desirable to subject the laminate or final product to a post-cure separate from compression. This step is designed to complete the curing reaction. Post-cure is typically carried out at about 130°C to about 220°C for a period of about 20 minutes to about 200 minutes. This post-cure step may be carried out in a vacuum to remove any volatilizable components.

[0132] Thus, according to yet another embodiment of the present disclosure, there is provided a method of making a laminate sheet, the method comprising layering and forming a predetermined number of sheets of prepreg according to the present disclosure.

[0133] According to a further embodiment of the present disclosure, there is provided a printed wiring board obtained by forming a conductive pattern on the surface of the above-mentioned laminate sheet(s). Forming the conductive pattern can be carried out, for example, by forming a resist pattern on the surface of the laminate sheet(s), removing unnecessary parts of the sheet by etching, removing the resist pattern, forming necessary through holes by drilling, forming a resist pattern again, connecting the through holes by plating, and finally removing the resist pattern.

[0134] According to another further embodiment of the present disclosure, there is provided a multilayer printed wiring board obtained by layering and molding a predetermined number of sheets of the above-described patterned laminate layer bonded together with one or more layers of prepreg from which the printed wiring board layer is prepared.

[0135] According to another further embodiment of the present invention, there is provided a method of making a printed wiring board, the method comprising forming a conductive pattern on a surface of a laminate sheet according to the present disclosure.

[0136] According to yet another embodiment of the present disclosure, there is provided a multilayer printed wiring board obtained by layering and molding a predetermined number of sheets of the above-described prepreg to obtain a printed wiring board for an inner layer, and layering the prepreg on the printed wiring board for an inner layer to form a conductive pattern on the surface thereof.

[0137] Thus, the prepregs and printed wiring boards of the present disclosure can be typically used as components of printed circuit boards for networks for use in various electric and electronic devices (such as mobile communication devices or base station devices thereof that process high frequency signals of GHz or more) and network-related electronic devices (such as servers and routers) and large computers.

[0138] In some embodiments, the resin compositions of the present invention may have a flat dissipation factor (Df) over a wide frequency range, so that components fabricated therefrom may operate efficiently at several different processing speeds. This is important because many cutting-edge electronic devices may operate over a wide frequency range, and it is therefore desirable for the electronic components to maintain proper functionality throughout this frequency range.

[0139] It has been discovered that by using the compositions of the present invention, it is possible to achieve ultra-low dielectric loss factors Df in the gigahertz range (e.g., 1-10 GHz, less than 0.005 at 10 GHz), which is unexpected in light of the prior art.

[0140] Specifically, the curable resin composition according to the present invention has a dielectric constant of less than 0.005, preferably less than 0.004, when measured with a split post dielectric resonator (SPDR) at a frequency of 10 GHz. and more preferably provides an article after curing having a dissipation factor (Df) of less than 0.0035.

[0141] According to particularly preferred embodiments, articles obtained by curing the compositions of the present disclosure have a dielectric constant (Dk) at 10 GHz of less than about 4 or less than about 3.5.

[0142] Specifically, the curable resin compositions according to the present invention provide, after curing, articles having a Tg of about 100°C or greater, preferably about 150°C or greater, and more preferably greater than about 200°C.

[0143] The present disclosure will now be further described with reference to the following non-limiting examples. [Example]

[0144] material: Priamine 1075®: an aliphatic C36 dimer diamine commercialized by CRODA DAPI: An aromatic amine (diamino-1,3,3-trimethyl-1-phenylindane) commercialized by HUNTSMAN. Pyromellitic dianhydride is commercialized by CABB Group (ex-JAYHAWK).

[0145] Example 1 - Preparation of bismaleimide compounds

[0146] Example 1a - Preparation of a bismaleimide compound according to the present invention: To a 2 L reaction flask equipped with a stirrer and a Dean-Stark trap, 0.2734 mol of pyromellitic dianhydride in 550 ml of toluene and 220 ml of N-methylpyrrolidone was added, and the mixture was heated to 90-95 °C. 0.082 mol of Priamine 1075® in 120 ml of toluene was added, and the mixture was allowed to react under reflux for 20 minutes. 0.328 mol of 4',5-6-diamino-1,3,3-trimethyl-1-phenylindane (DAPI) in 110 ml of toluene and 130 ml of N-methylpyrrolidone was added. The temperature was increased to 125 °C, and the mixture was allowed to react under reflux for 2 hours. The reaction mixture was cooled to 100 °C, and 0.3034 mol of maleic anhydride and 0.0802 mol of p-toluenesulfonic acid monohydrate were added. The temperature was raised to 125°C, and the reaction was continued under reflux for 5 hours. The solution was washed with brine, and the toluene was removed under vacuum. The solid was then purified by dissolving in N-methylpyrrolidone, followed by precipitation in methanol and drying under vacuum. The mass yield was 70%. Analyses performed included 1H, 1C NMR, HPLC, GC, and GPC, and the structure of the expected product was confirmed in the reaction mixture.

[0147] Example 1b - Preparation of a comparative bismaleimide compound: Follow the protocol of Example 1a, substituting DAPI for Priamine 1075®.

[0148] Example 1c - Preparation of a comparative bismaleimide compound: Follow the protocol of Example 1a, substituting Priamine 1075® for DAPI.

[0149] Example 2 - Preparation of Resin Compositions of the Invention and Comparative Resin Compositions The components shown in Table 1 were dissolved in toluene at room temperature to obtain homogeneous resin composition varnishes with solid content concentrations of 50 to 60% by weight (compositions C1a, C1b, and C1c). [Table 1]

[0150] Example 3 - Applications - Preparation of Prepregs and Laminates A glass cloth (E2116NE glass) was immersed in the varnish, then placed vertically in an oven and dried at 140°C for 2 minutes to obtain a prepreg sheet. The prepreg sheets were compression cured at 220° C. for 2 hours, so that the resin content in the final laminate was about 45% to about 50% by weight. The resulting laminates with a thickness of approximately 0.5 mm were evaluated for dielectric constant (Dk) and dissipation factor (Df) in a split post dielectric resonator (SPDR) at a frequency of 10 GHz, as well as for glass transition measurements in vibration mode from 23°C to 300°C at 2°C / min at 1 Hz. The glass transition was determined by G' onset and tan delta maximum. [Table 2]

[0151] The results clearly demonstrate the effect of utilizing a mixture of aromatic and aliphatic amines: the dielectric loss of the fully aromatic bismaleimide (Comparative Example 1b) is significantly increased compared to Example 1a, while the aliphatic amine-based bismaleimide (Comparative Example 1c) has a significantly lower glass transition temperature than Example 1a.

[0152] While the above provides a detailed description of making and using various embodiments of the invention, it should be understood that the invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.

Claims

1. Formula (I): 【Chemistry 1】 A bismaleimide compound of the formula: During the ceremony, n is an integer, n ranges from 1 to 10; m is an integer, m ranging from 1 to 10; each Q is independently a tetravalent radical selected from a C6-C50 hydrocarbon containing at least one aromatic group and optionally one or more heteroatoms selected from O, N, S, F, Cl, Br; each R1 is independently a divalent radical selected from aliphatic and aromatic straight or branched chain C1 to C60 hydrocarbyls optionally containing one or more NH2 groups, one or more NH bridges; each R2 is independently a divalent radical selected from a C6 to C54 aromatic hydrocarbon optionally containing one or more halogen atoms; R is a divalent radical R or R, Y is H or CH ３ The bismaleimide compound represented by the formula:

2. Q is selected from the following structures: 【Chemistry 2】 2. The bismaleimide compound of claim 1, wherein Q' is a divalent radical selected from C1 to C38 hydrocarbons optionally containing one or more heteroatoms selected from O, N, S, F, Cl, and Br.

3. 3. The bismaleimide compound of claim 1 or claim 2, wherein each R1 is independently selected from one or more NH2 groups, C12 to C60 alkyl, alkenyl, or aralkyl, optionally containing one or more NH bridges.

4. Each R2 is a group of formula (IIIA) 【Transformation 3】 are independently selected from the divalent radicals During the ceremony, Y1 and Y2 independently represent H or C1-C5 alkyl; The bismaleimide compound according to any one of claims 1 to 3, wherein each Y3 and Y4 independently represents H, halogen, or C1 to C4 alkyl.

5. A process for the preparation of the bismaleimide compounds according to any one of claims 1 to 4, said process comprising the steps of: 【Chemistry 4】 Step 1: Reacting a dianhydride (IV) with a diamine of formula (II) and a diamine of formula (III) to obtain an amine-terminated extended imide (V); Step 2: reacting the amine-terminated extended imide (V) obtained from step 1 with a maleic anhydride compound (VI); During the ceremony, n, m, Q, R1, R2, R, and Y have the same definitions as in formula (I); An and Am are the ratios of the amount of the diamine H introduced into the reaction medium relative to the amount of the dianhydride (IV), respectively. ２ N-R1-NH ２ and the diamine H ２ N-R2-NH ２ The method of claim 1, wherein the relative molar amounts of

6. 6. The method of claim 5, wherein the ratio of the total amount of amine (Am+An) to the dianhydride compound ranges from about 5:1 to about 1.05:

1.

7. 7. The method according to claim 5 or claim 6, wherein the molar ratio Am / An of the aromatic amine(s) (III) to the aliphatic amine(s) (II) is in the range of about 20:1 to about 1:1, more preferably in the range of about 10:1 to about 2:1, even more preferably in the range of about 5:1 to about 3:1, and advantageously about 4:

1.

8. The method according to any one of claims 5 to 7, wherein the first step of the method proceeds in two sub-steps: Sub-step 1a: reacting the dianhydride (IV) with a compound of formula H ２ N-R1-NH ２ reacting with an aliphatic diamine of (II); Sub-step 1b: The product obtained from sub-step 1a is reacted with the aromatic diamine H ２ N-R2-NH ２ to give the amine-terminated extended imide (V).

9. The method according to any one of claims 5 to 8, wherein the method is carried out in one pot.

10. A bismaleamide compound obtained by the method according to any one of claims 5 to 9.

11. A curable resin composition comprising at least the bismaleimide compound of formula (I) according to any one of claims 1 to 4 or claim 10, and at least one co-curing agent.

12. 12. The curable resin composition of claim 11, wherein the co-curing agent is selected from polyphenylene ether derivatives, maleimide, styrene, divinylbenzene, trivinylcyclohexane, trialkenyl isocyanurate compounds, and mixtures thereof, preferably trialkenyl isocyanurate compounds (such as triallyl isocyanurate).

13. 13. The curable resin composition according to claim 11 or claim 12, wherein the bismaleamide compound represents about 20 to about 99 wt %, more preferably about 30 to about 98 wt %, of the total weight of the resin composition, and the co-curing agent represents about 1% to about 50%, preferably about 2% to about 20%, based on the total weight of the composition.

14. A process for manufacturing an article comprising at least the steps of: - Step 1: Preparing the curable resin composition according to any one of claims 11 to 13; - Step 2: shaping the composition; - Step 3: Partially or fully curing the composition.

15. 15. An article obtainable by the method of claim 14.

16. 16. The article of claim 15, having a dissipation factor (Df) of less than 0.005, preferably less than 0.004, more preferably less than 0.0035, as measured in a split post dielectric resonator (SPDR) at a frequency of 10 GHz, a dielectric constant (Dk) at 10 GHz of less than about 4 or less than about 3.5, and a Tg of 100°C or greater, preferably 150°C or greater, more preferably greater than 200°C.

17. By impregnating a fiber material with the composition according to any one of claims 1 to 4 or 10, 17. The article according to claim 15 or claim 16, which is a prepreg obtained by the above method.

18. 20. A laminate comprising the prepreg of claim 17 and a layer of conductive material disposed on at least one surface of the prepreg.

19. A printed wiring board obtained by forming a conductive pattern on the surface of the laminate according to claim 18.

20. Use of the resin composition according to any one of claims 1 to 4 and claim 10 in prepregs, metal clad laminates, printed circuit boards, light emitting diodes, electronic coatings, textiles, polymeric molding compounds, medical molding compounds, and adhesives.

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