HK1192895A

HK1192895A - Halogen free thermoset resin system for low dielectric loss at high frequency applications

Info

Publication number: HK1192895A
Application number: HK14106413.0A
Authority: HK
Inventors: R．蒂策; Y-L．古彦
Original assignee: 亨斯迈先进材料美国有限责任公司
Priority date: 2011-05-17
Filing date: 2012-05-09
Publication date: 2014-09-05

Description

Halogen-free thermosetting resin system with low dielectric loss in high frequency applications

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable to

Declaration of federally sponsored research or development

Not applicable to

Technical Field

The present disclosure relates to a polymaleimide-based thermosetting resin composition and to their use in a variety of applications, for example, in the preparation of prepregs, laminates for printed wiring boards, molding compounds and adhesives.

Background

Articles prepared from resin compositions having improved high temperature resistance and low dielectric loss for elevated temperatures are desirable for many applications. In particular, due to the industry's trend toward higher circuit densities, increased board thicknesses, lead-free soldering, higher temperatures, and higher frequency use environments, such articles are desirably suitable for prepregs and laminates for Printed Circuit Board (PCB) and semiconductor applications.

Laminates, and in particular structural and electrical copper clad laminates, are typically prepared by pressing multiple layers of partially cured prepreg and optionally copper sheet at elevated temperature and pressure. Prepregs are typically prepared by: the curable thermosetting epoxy resin composition is impregnated into a porous substrate, e.g., a fiberglass mat, and then treated at elevated temperatures to promote partial curing of the epoxy resin in the mat to a "B-stage". During the lamination step, complete curing of the epoxy resin impregnated in the glass fiber mat typically occurs when the prepreg layer is pressed at high pressure and elevated temperature for a period of time.

Although epoxy resin compositions are known to impart improved thermal performance to the preparation of prepregs and laminates, such epoxy resin compositions are generally more difficult to handle, more expensive to formulate, and may suffer from poor performance for complex printed circuit board circuits and for higher manufacturing and use temperatures.

Based on this, there is a need in the art for resin compositions that can be used to prepare articles with improved thermal properties and low dielectric loss at high frequencies, as well as methods for preparing such articles.

Disclosure of Invention

The present disclosure provides a thermosetting resin composition comprising:

(a) a polymaleimide prepolymer obtained by a chain extension reaction of a polyimide and an alkenylphenol, alkenylphenol ether or a mixture thereof in the presence of an amine catalyst;

(b) a poly (arylene ether) prepolymer obtained by a chain extension reaction of a poly (arylene ether) and an allylic monomer, optionally in the presence of a catalyst; characterized in that the resulting cured product formed by curing the thermosetting resin composition comprises at least two well-balanced properties of: (1) a glass transition temperature (Tg) greater than about 170 ℃; (2) a UL94 flame retardancy rating of at least V1; (3) a dielectric loss tangent of less than 0.005 at 16GHz, and (4) a dielectric loss constant of less than 3.00 at 16 GHz.

Another aspect of the present disclosure relates to the use of the above thermosetting resin to obtain a prepreg or a metal-clad foil; and a laminate obtained by laminating the prepreg and/or the metal-clad foil.

Detailed Description

According to one embodiment, the thermosetting resin composition disclosed herein is halogen-free or substantially halogen-free. The term "substantially halogen-free" as used herein means that the final composition does not contain any covalently bonded halogen groups, but may contain: a minimum amount of residual halogen present in any residual halogenated solvent or catalyst or residual amounts of halogen leached from any container or glassware used to synthesize and/or store the composition. In certain embodiments, substantially halogen-free means that the total halogen content in the final composition is less than about 0.12 weight percent, and more particularly, the total halogen content in the final composition is less than about 0.09 weight percent. Although residual amounts of halogen may be present in the final composition, the residual amounts do not impart or impair the physical properties of the final composition, e.g., flame retardancy, peel strength, dielectric properties, and the like. Furthermore, any residual amounts of halogen present during incineration do not produce significant amounts of dioxin, or other toxic substances, that are considered to be detrimental to the health of mammals (e.g., humans).

One of ordinary skill in the art will recognize, given the advantages of the present disclosure, that the thermosetting resin compositions, articles made using the thermosetting resin compositions, provide significant advantages not realized by prior art compositions. The thermosetting resin composition may be used in the assembly of a plurality of single or multi-layer articles, including, but not limited to, laminates, printed circuit boards, molded articles, automotive and aerospace plastics, silicon chip carriers, structural composites, fairing composites for aerospace applications, resin-clad foils, unreinforced substrates for high density circuit interconnect applications, and other suitable applications where it is desirable to use single or multi-layer articles having flame retardancy and/or excellent electrical properties, particularly at high frequencies.

According to one aspect, the present disclosure relates to a thermosetting resin composition comprising: (a) a polymaleimide prepolymer obtained by a chain extension reaction of a polyimide and an alkenylphenol, alkenylphenol ether or a mixture thereof in the presence of an amine catalyst; (b) a poly (arylene ether) prepolymer obtained by a chain extension reaction of a poly (arylene ether) and an allylic monomer, optionally in the presence of a catalyst; characterized in that the resulting cured product formed by curing the thermosetting resin composition comprises at least two well-balanced properties of: (1) a glass transition temperature (Tg) greater than about 170 ℃; (2) a UL94 flame retardancy rating of at least V1; (3) a dielectric loss tangent of less than 0.005 at 16GHz, and (4) a dielectric loss constant of less than 3.00 at 16 GHz. As used herein, "chain extension reaction" refers to a reaction in which the molecular weight of a particular compound is increased. In contrast, "cured product" refers to a cured thermoset resin whereby substantial networking or crosslinking occurs.

Polymaleimide prepolymers

According to one embodiment, the thermosetting resin composition of the present disclosure comprises: about 3 to 20 parts by weight, preferably about 5 to 18 parts by weight, and more preferably about 7 to 15 parts by weight, based on 100 parts by weight of the thermosetting resin composition, of a polymaleimide prepolymer obtained by chain-extension reaction of a polyimide with an alkenylphenol, alkenylphenol ether, or a mixture thereof in the presence of an amine catalyst.

The applicable polyimides contain at least two groups of the formula

Wherein R is¹Is hydrogen or methyl. In one embodiment, the polyamide is a bismaleimide of the formula

Wherein R is¹Is hydrogen or methyl, and X is-C_iH_2i-, where i =2 to 20, -CH₂CH₂SCH₂CH₂-, phenylene, naphthylene, xylylene, cyclopentylene, 1,5, 5-trimethyl-1, 3-cyclohexylene, 1, 4-bis- (methylene) -cyclohexylene or a group of the formula,

wherein R is²And R³Independently methyl, ethyl or hydrogen, and Z is a direct bond, methylene, 2-propylene, -CO-, -O-, -S-, -SO-or-SO₂-. Preferably, R¹Is methyl, X is hexamethylene, trimethylhexamethylene, 1,5, 5-trimethyl-1, 3-cyclohexylene or a group of the general formula (a), wherein Z is methylene, 2-propylene or-O-, and R²And R³Is hydrogen.

Applicable alkenyl phenols and alkenyl phenol ethers may include allyl phenol, methallyl phenol, or ethers thereof. Preferably, the alkenylphenols and alkenylphenol ethers are compounds of the general formulae (1) to (4):

wherein R is a direct bond, methylene, isopropylidene, -O-, -S-, -SO-or-SO-₂-；

Wherein R is⁴、R⁵And R⁶Each independently is hydrogen or C₂-C₁₀Alkenyl, preferably allyl or propenyl, with the proviso that R⁴、R⁵Or R⁶At least one of them is C₂-C₁₀An alkenyl group;

wherein R is⁴、R⁵、R⁶And R⁷Each independently is hydrogen or C₂-C₁₀Alkenyl, preferably allyl or alkenyl, with the proviso that R⁴、R⁵、R⁶Or R⁷At least one of them is C₂-C₁₀Alkenyl, and R is as defined in the general formulae (1) and (4)

Wherein R is⁸、R⁹、R¹⁰、R¹¹、R¹²And R¹³Each independently is hydrogen, C₁-C₄Alkyl and C₂-C₁₀Alkenyl, preferably allyl or propenyl, with the proviso that R⁸、R⁹、R¹⁰、R¹¹、R¹²And R¹³At least one of them is C₂-C₁₀Alkenyl, and b is an integer of 0 to 10. It is also possible to use mixtures of compounds of the general formulae (1) to (4).

Examples of the alkenylphenol and alkenylphenol ether compounds include: o, O '-diallyl-bisphenol A, 4' -dihydroxy-3, 3 '-diallyldiphenyl, bis (4-hydroxy-3-allylphenyl) methane, 2-bis (4-hydroxy-3, 5-diallylphenyl) propane, O' -dimethylallyl-bisphenol A, 4 '-dihydroxy-3, 3' -dimethylallyl-diphenyl, bis (4-hydroxy-3-methylallylphenyl) methane, 2-bis (4-hydroxy-3, 5-dimethylallylphenyl) -propane, 4-methylallyl-2-methoxyphenol, 2-bis (4-methoxy-3-allylphenyl) propane, 2, 2-bis (4-methoxy-3-methylallylphenyl) propane, 4 '-dimethoxy-3, 3' -diallyldiphenyl, 4 '-dimethoxy-3, 3' -dimethylallyldiphenyl, bis (4-methoxy-3-allylphenyl) methane, bis (4-methoxy-3-methylallylphenyl) methane, 2-bis (4-methoxy-3, 5-diallylphenyl) propane, 2-bis (4-methoxy-3, 5-dimethylallylphenyl) propane, 4-allylveratrole and 4-methylallylveratrole.

The alkenylphenol, alkenylphenol ether, or mixture thereof may be used in an amount of about 0.05 moles to about 2.0 moles per mole of the polyimide. In another embodiment, the alkenylphenol, alkenylphenol ether, or mixture thereof may be used in an amount of about 0.1 to 1.0 mole per mole of polyimide.

Amine catalysts that can be used include tertiary, secondary and primary amines or amines containing some different type of amino group therein, and quaternary ammonium compounds. The amine may be a monoamine or polyamine, and may include: diethylamine, tripropylamine, tributylamine, triethylamine, tripentylamine, benzylamine, tetramethyl-diaminodiphenylmethane, N-diisobutylaminoacetonitrile, N-dibutylaminoacetonitrile; heterocyclic bases, for example quinoline, N-methylpyrrolidine, imidazole, benzimidazole and their homologues, also for example mercaptobenzothiazole. Examples of suitable quaternary ammonium compounds which may be mentioned are benzyltrimethylammonium hydroxide and benzyltrimethylammonium methoxide. Tripropylamine is preferred.

The basic catalyst may be used in an amount of about 0.1wt% to 10wt% based on the total weight of the chain extension reactants. In other embodiments, the basic catalyst may be present in an amount of about 0.2wt% to 5wt% of the total weight of the chain extension reactants.

The method for preparing the polymaleimide prepolymer comprises the following steps: the polyimide and the alkenylphenol, alkenylphenol ether, or mixture thereof are mixed and the mixture is heated to about 25 ℃ to 150 ℃ until a clear melt is obtained. The amine catalyst is then added and the reaction is continued at a temperature of about 100 ℃ to 140 ℃ for a suitable amount of time, then all of the amine catalyst is removed under vacuum. The extent of chain extension can be monitored by measuring the melt viscosity of the resin at 125 ℃ using a poise scale (poise scale) of 0 to 100, which can range from 20 to 85 poise for the chain extended polymaleimide prepolymer. Gel time may also be used as an additional parameter, reflecting the time for total gel formation when measured at a temperature of about 170 ℃ to 175 ℃ and may be 300-.

Poly (arylene ether) prepolymer

The thermosetting resin composition of the present disclosure further comprises: about 80 to 97 parts by weight, preferably about 82 to 95 parts by weight, based on 100 parts by weight of the thermosetting resin composition, of a poly (arylene ether) prepolymer resulting from a chain extension reaction of a poly (arylene ether) and an allylic monomer.

In one embodiment, the poly (arylene ether) comprises one or more compounds comprising a plurality of structural units having the formula:

wherein, for each structural unit, Q is¹Independently is primary or secondary C₁-C₁₂Hydrocarbyl radical, C₁-C₁₂Mercapto or C₁-C₁₂A hydrocarbyloxy group; and in each case Q²Radix rehmanniae is primary or secondary C₁-C₁₂Hydrocarbyl radical, C₁-C₁₂Hydrocarbyloxy or C₁-C₁₂A hydrocarbyloxy group. The term "hydrocarbyl", by itself or as a prefix, suffix, or fragment of another term, refers to a residue that contains only carbon and hydrogen. The residue may be aliphatic or aromatic, straight-chain, cyclic, bicyclic, branched, saturated or unsaturated. It may contain aliphatic, aromatic,Combinations of linear, cyclic, bicyclic, branched, saturated, and unsaturated hydrocarbon moieties. However, when the hydrocarbyl residue is described as "substituted," it may contain heteroatoms over and above the carbon and hydrogen members of the substituent residue. Thus, when specifically described as substituted, the hydrocarbyl residue may also contain nitro groups, cyano groups, carbonyl groups, carboxylic acid groups, ester groups, amino groups, amide groups, sulfonyl groups, sulfoxide groups (sulfoxyl groups), sulfonamide groups, sulfamoyl groups, hydroxyl groups, alkoxy groups, and the like, and may contain heteroatoms within the backbone of the hydrocarbon residue.

In some embodiments, the poly (arylene ether) comprises 2, 6-dimethyl-1, 4-phenylene ether units, 2,3, 6-trimethyl-1, 4-phenylene ether units, or a combination thereof. In other embodiments, the poly (phenylene ether) is a poly (2, 6-dimethyl-1, 4-phenylene ether), and in other embodiments, the poly (arylene ether) is a copolymer of 2, 6-dimethylphenol and 2,3, 6-trimethylphenol.

The poly (arylene ether) can also comprise molecules having aminoalkyl-containing terminal group, typically in an ortho position to the hydroxy group. Further, typically present are tetramethyl dibenzoquinone (TMDQ) end groups, typically obtained from a 2, 6-dimethylphenol-containing reaction mixture in which tetramethyl dibenzoquinone by-product is present.

In some embodiments, the poly (arylene ether) may be in the form of a homopolymer, copolymer, graft copolymer, ionomer, or block copolymer, and combinations thereof.

The poly (arylene ether) may be prepared by the oxidative coupling of monohydroxyaromatic compounds, such as 2, 6-dimethylphenol and/or 2,3, 6-trimethylphenol. Catalyst systems are typically employed for such attachment, which may comprise heavy metal compounds, for example, copper, manganese or cobalt compounds, typically in combination with a variety of other materials (e.g., secondary amines, tertiary amines, halides or combinations of two or more of the foregoing).

In other embodiments, the poly (arylene ether) can have a number average molecular weight of 3,000-40,000 grams per mole (g/mol) and a weight average molecular weight of 5,000-80,000g/mol as determined by gel permeation chromatography using monodisperse polystyrene standards, a styrene divinylbenzene gel at 40 ℃, and a sample having a concentration of 1 mg/1 ml of chloroform. The poly (arylene ether) or combination of poly (arylene ether) s may have an initial intrinsic viscosity of 0.1 to 0.60 deciliters per gram (dl/g) when measured at 25 ℃ in chloroform. Initial intrinsic viscosity is defined as the intrinsic viscosity of the poly (arylene ether) prior to melt mixing with the other components of the composition, and final intrinsic viscosity is defined as the intrinsic viscosity of the poly (arylene ether) after melt mixing with the other components of the composition. It should be understood by those skilled in the art that the viscosity of the poly (arylene ether) may be increased by up to 30% after melt mixing. The percentage increase can be calculated as follows: (final intrinsic viscosity-initial intrinsic viscosity)/initial intrinsic viscosity. When two initial intrinsic viscosities are used, the determination of the exact ratio will depend in part on the exact intrinsic viscosities of the poly (arylene ether) used and the ultimate physical properties desired.

According to another embodiment, the poly (arylene ether) is a functionalized poly (arylene ether). The functionalized poly (arylene ether) may be a capped poly (arylene ether), a diterminated poly (arylene ether), a ring-functionalized poly (arylene ether), or a poly (arylene ether) resin comprising at least one terminal functional group selected from carboxylic acids, glycidyl ethers, vinyl ethers, and anhydrides.

In one embodiment, the functionalized poly (arylene ether) comprises a capped poly (arylene ether) having the general formula:

A(J-K)_y

wherein A is the residue of a monohydric, dihydric or polyhydric phenol, y is an integer from 1 to 100, preferably from 1 to 6, and J is a compound of the formula:

for each structural element, Q³Independently of one another, primary or secondary C₁-C₁₂Alkyl radical, C₂-C₁₂Alkenyl radical, C₂-C₁₂Alkynyl, C₁-C₁₂Aminoalkyl radical, C₁-C₁₂Hydroxyalkyl, phenyl or C₁-C₁₂A hydrocarbyloxy group; and in each case Q⁴Independently is primary or secondary C₁-C₁₂Alkyl radical, C₂-C₁₂Alkenyl radical, C₂-C₁₂Alkynyl, C₁-C₁₂Aminoalkyl radical, C₁-C₁₂Hydroxyalkyl, phenyl or C₁-C₁₂A hydrocarbyloxy group; m is an integer from 1 to about 200; and K is a capping group selected from:

wherein Q is⁵Is C₁-C₁₂An alkyl group; q⁶、Q⁷And Q⁸Each independently selected from hydrogen and C₁-C₁₂Alkyl radical, C₂-C₁₂Alkenyl radical, C₆-C₁₈Aryl radical, C₇-C₁₈Alkyl-substituted aryl, C₇-C₁₈Aryl-substituted alkyl; c₂-C₁₂Alkoxycarbonyl group, C₇-C₁₈Aryloxycarbonyl group, C₈-C₁₈Alkyl-substituted aryloxycarbonyl, C₈-C₁₈Aryl substituted alkoxycarbonyl, cyano, formyl, carboxylate, imidate (imidate) and thiocarboxylate (thiocarboxylate); and Q⁹、Q¹⁰、Q¹¹、Q¹²And Q¹³Each independently selected from hydrogen and C₁-C₁₂Alkyl, hydroxy and amino; and Y is a divalent group selected from:

wherein Q is¹⁴And Q¹⁵Each independently selected from hydrogen and C₁-C₁₂An alkyl group.

In one embodiment, a is phenol, includes the residue of a multifunctional phenol, and includes groups of the following structure:

wherein Q is³And Q⁴W is hydrogen, C as defined above₁-C₁₈Hydrocarbyl or C containing substituents₁-C₁₈Hydrocarbyl radicals, e.g. carboxylic acids, aldehydes, alcohols, amino groups, sulfur, sulfonyl groups, thioacyl groups, oxygen, C₁-C₁₂Alkylene groups or other bridging groups having a valence above 2 which form a plurality of di-or higher polyphenols; and n is an integer of 1 to 100, preferably 1 to 3.

In other embodiments, a is the residue of a monohydric phenol, a diphenol (e.g., 2 ', 6,6 ' -tetramethyl-4, 4' -diphenol), or a bisphenol (e.g., bisphenol a).

Thus, in one embodiment, the capped poly (arylene ether) is prepared by capping a poly (arylene ether) consisting essentially of the polymerization product of at least one monohydric phenol having the structure:

wherein Q is³And Q⁴As defined above. Suitable examples of monohydric phenols include, but are not limited to, 2, 6-dimethylphenol and 2,3, 6-trimethylphenol. The poly (arylene ether) may further comprise at least two monohydric phenols(e.g., 2, 6-dimethylphenol and 2,3, 6-trimethylphenol).

In yet another embodiment, the capped poly (arylene ether) comprises a diterminated poly (arylene ether) having the structure:

wherein, in each case, Q³And Q⁴As defined above: in each case, Q¹⁶Independently hydrogen or methyl; in each instance, t is an integer from 1 to about 100; z is 0 or 1; and Y has a structure selected from:

wherein, in each case, Q¹⁷And Q¹⁸And Q¹⁹Independently selected from hydrogen and C₁-C₁₂A hydrocarbyl group.

Procedures for capping poly (arylene ether) s are known to those skilled in the art, for example, as taught in U.S. Pat. Nos. 6,306,978 and 6,627,704, the contents of which are incorporated herein by reference. Thus, a capped poly (arylene ether) may be formed by reacting an uncapped poly (arylene ether) with a capping agent. Capping agents include, but are not limited to, monomers or polymers containing anhydride, acid chloride, epoxy, carbonate, ester, isocyanate, or cyanate ester groups. For example, the capping agent may be acetic anhydride, succinic anhydride, maleic anhydride, salicylic anhydride, acrylic anhydride, methacrylic anhydride, a polyester comprising salicylate units, a homopolyester of salicylic acid, acrylic anhydride, methacrylic anhydride, glycidyl acrylate, glycidyl methacrylate, bis (4-nitrophenyl) carbonate, phenyl isocyanate, 3-isopropenyl-alpha, alpha-dimethylphenyl isocyanate, phenyl cyanate, or 2, 2-bis (4-cyanatophenyl) propane).

In yet another embodiment, the functionalized poly (arylene ether) comprises a ring-functionalized poly (arylene ether) having repeating structural units of the formula:

wherein, in each case, L¹And L²Independently of one another is hydrogen, C₁-C₁₂An alkyl group, an alkenyl group represented by the general formula:

wherein L is³、L⁴And L⁵Independently hydrogen or methyl, and e is an integer from 0 to 4, or an alkynyl group represented by the formula:

wherein L is⁶Is hydrogen, methyl or ethyl, and f is an integer from 0 to 4; and wherein about 0.02 mol% to about 25 mol% of total L¹And L²The substituents are alkenyl and/or alkynyl groups.

In another embodiment, the ring-functionalized poly (arylene ether) is the melt reaction product of a poly (arylene ether) and an α, β -unsaturated carbonyl compound or a β -hydroxycarbonyl compound. Examples of the α, β -unsaturated carbonyl compound include maleic anhydride and citraconic anhydride. Examples of beta-hydroxycarbonyl compounds include citric acid. The functionalization may be performed by melt mixing the poly (arylene ether) with the desired carbonyl compound at a temperature of about 190 ℃ to about 290 ℃.

According to another embodiment, the functionalized poly (arylene ether) comprises at least one terminal functional group selected from the group consisting of a glycidyl ether of a carboxylic acid, a vinyl ether, and an anhydride. Suitable methods for preparing these can be found, for example, in EP0261574B1, u.s6,794,481, and US6,835,785, and U.S. patent publication nos. 2004/0265595 and 2004/0258852, the contents of which are incorporated by reference into this application.

In some embodiments, the functionalized poly (arylene ether) has a number average molecular weight of about 500g/mol to about 18,000 g/mol.

The allyl monomer may be a mono, di, or polyallyl monomer, or a mixture thereof. According to one embodiment, the allyl monomer is selected from triallyl isocyanurate, trimethylallyl isocyanurate, triallyl cyanurate, trimethylallyl cyanurate, diallylamine, triallylamine, diallyl chlorendate (diacryl chlorendate), allyl acetate, allyl benzoate, allyl dipropyl isocyanurate, allyl octyl oxalate, allyl propyl phthalate, butylallyl malate, diallyl adipate, diallyl carbonate, diallyl dimethyl ammonium chloride, diallyl fumarate, diallyl isophthalate, diallyl malonate, diallyl oxalate, diallyl phthalate, diallyl isopropyl isocyanurate, diallyl sebacate, diallyl succinate, diallyl terephthalate, diallyl phthalate, diallyl talolate, dimethylallyl phthalate, ethylallyl malate, methylallyl fumarate, and methylmethacllyl malate. Of these monomers, triallyl isocyanurate (hereinafter referred to as TAIC) and trimethylallyl isocyanurate (hereinafter referred to as TMAIC) are particularly desirable.

The chain extension of the poly (arylene ether) is carried out by reacting the poly (arylene ether) with an allylic monomer, optionally in the presence of a catalyst. In one embodiment, the catalyst is a metal acetylacetonate having the structure:

wherein M is selected from the group consisting of aluminum, barium, cadmium, calcium, cerium (III), chromium (III), cobalt (II), cobalt (III), copper (II), indium, iron (III), lanthanum, lead (II), manganese (III), neodymium, nickel (II), palladium (II), potassium, samarium, sodium, terbium, titanium, vanadium, yttrium, zinc, and zirconium.

In other embodiments, the catalyst is an organic peroxide, for example, dicumyl peroxide, t-butylcumyl peroxide, bis (t-butylperoxyisopropyl) benzene, di-t-butyl peroxide, 2, 5-dimethylhexane-2, 5-hydroperoxide, 2, 5-dimethylhexyne-3, 2, 5-hydroperoxide, dibenzoyl peroxide, bis- (2, 4-dichlorobenzoyl) peroxide, or t-butyl perbenzoic acid. In yet other embodiments, the catalyst is a cobalt salt, e.g., cobalt octoate or cobalt naphthenate, or a metal catalyst, e.g., manganese or cyanoureic anhydride. In another embodiment, the catalyst is a Grubbs catalyst having the general formula:

the catalyst may be used in an amount of about 0.25 parts to about 1.25 parts, preferably about 0.5 parts to about 1 part, based on 100 parts by weight of the poly (arylene ether).

According to one embodiment, the chain growth reaction is initiated by contacting the poly (arylene ether) with an allylic monomer and optionally a catalyst to form a chain growth reaction mixture. The amounts of poly (arylene ether) and allylic monomer contacted in the chain extension reaction include greater than 50 weight percent of poly (arylene ether) and less than 50 weight percent of allylic monomer, based on the total weight of the chain extension reaction mixture. In another embodiment, the amounts of poly (arylene ether) and allyl monomer contacted in the chain extension reaction comprise at least about 50.5 to about 70 parts by weight of poly (arylene ether) and at least about 30 to about 49.5 parts by weight of allyl monomer, based on 100 parts by weight of the chain extension reaction mixture. In yet another embodiment, the amounts of poly (arylene ether) and allyl monomer contacted in the chain extension reaction comprise at least about 51 to 60 parts by weight of poly (arylene ether) and at least about 40 to 49 parts by weight of allyl monomer, based on 100 parts by weight of the chain extension reaction mixture.

Conditions under which the chain extension reaction occurs include: a high vacuum and a temperature in the range of at least about 140 ℃ to less than about 150.5 ℃. The reaction is continued for a sufficient period of time to allow the poly (arylene ether) prepolymer to reach the desired average molecular weight. According to one embodiment, the chain extension reaction is allowed to continue until the poly (arylene ether) prepolymer reaches an average molecular weight of at least 40,000 g/mol. In another embodiment, the chain extension reaction is allowed to continue until the poly (arylene ether) reaches an average molecular weight of at least 50,000g/mol, and in yet another embodiment, it is allowed to continue until the poly (arylene ether) reaches an average molecular weight of at least about 60,000 g/mol. In another embodiment, the chain extension reaction is continued until the poly (arylene ether) reaches an average molecular weight of no more than about 160,000g/mol, and in other embodiments, the reaction is continued until the poly (arylene ether) reaches an average molecular weight of no more than about 140,000 g/mol. The reaction time required to achieve the desired average molecular weight will vary, but will generally range from about 0.1 hour to about 20 hours, preferably from about 0.5 hours to about 16 hours, in most embodiments.

Flame retardant

In other aspects, the thermosetting resin composition may further comprise a phosphorylated flame retardant. In certain embodiments, the thermosetting resin composition comprises about 1 to about 20 parts by weight of the phosphorylated flame retardant, based on 100 parts by weight of the thermosetting resin composition. In other embodiments, the thermosetting resin composition comprises about 4 to about 15 parts by weight of the phosphorylated flame retardant, and preferably about 5 to about 10 parts by weight of the phosphorylated flame retardant, based on 100 parts by weight of the thermosetting resin composition.

The exact chemical form of the phosphorylated flame retardant may vary based on the thermosetting resin composition. For example, in certain embodiments, the phosphorylated flame retardant has the general formula shown in general formulas (5) - (7):

and

in the general formulae (5) to (7), D₂、D₃And D₄Each of which may be independently selected from substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted alicyclic groups, and substituted or unsubstituted heterocyclic groups containing nitrogen, oxygen, and/or phosphorus, and g is an integer of 1 to 20.

Exemplary commercially available materials that can be used include, but are not limited to, ammonium polyphosphates (ammonium polyphosphates), such as Exolit APP-422 and APP-423 (available from Clariant), andMC flame retardants (available from Albemarle), melamine phosphates, e.g., Melapurg-200 and Melapurg-MP (available from Ciba) and Fyrol (V-MP) (available from Akzo Nobel), organic phosphates, e.g., OP-930 and OP-1230 (available from Clariant) and polyphenylene phosphates, e.g., Fyrol PMP (available from Akzo Nobel).

Optional additives

If necessary, the thermosetting resin may further include additives for improving strength, mold release properties, hydrolysis resistance, electrical conductivity, and other characteristics. The amount of the additive that may be added to the thermosetting resin composition may be less than about 50 parts by weight, preferably less than about 30 parts by weight, and most preferably less than about 20 parts by weight, based on 100 parts by weight of the thermosetting resin composition.

Such optional additives may include inert particulate fillers, for example, talc, clay, mica, silica, alumina, and calcium carbonate. Fabric wettability enhancing agents (e.g., wetting agents and coupling agents) are also advantageous under certain conditions. In addition, such materials may also be present as antioxidants, heat and uv stabilizers, lubricants, antistatic agents, microspheres and hollow spheres, dyes and pigments.

Organic solvent

In some embodiments, the thermosetting resin composition may be dissolved or dispersed in an organic solvent. The amount of solvent is not limited, but is typically provided in an amount sufficient to provide a concentration of solids in the solvent of at least 30% to no more than 90% solids, preferably from about 55% to about 85% solids, and more preferably from about 60% to about 75% solids.

The organic solvent is not particularly limited, and may be a ketone, an aromatic hydrocarbon, an ester, an amide, a heterocyclic acetal, or an alcohol. More specifically, examples of the organic solvent that can be used include: acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, xylene, methoxyethyl acetate, ethoxyethyl acetate, butoxyethyl acetate, ethyl acetate, N-methylpyrrolidone formamide, N-methylformamide, N-dimethylacetamide, methanol, ethanol, 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, 1, 3-dioxolane, and mixtures thereof.

The thermosetting resin compositions of the present disclosure can be prepared by known means, for example, by premixing individual components and then mixing the premixes, or by mixing all of the components together using conventional equipment (e.g., stirred vessels, stirred rods, ball mills, sample mixers, static mixtures, or ribbon mixers). Once formulated, the thermosetting resin compositions of the present disclosure may be packaged in a variety of containers, such as steel, tin, aluminum, plastic, glass, or cardboard containers.

According to another embodiment, the thermosetting resin composition of the present disclosure is prepared by: about 3 to 20 parts by weight of the polymaleimide prepolymer and about 80 to 97 parts by weight of the poly (arylene ether) prepolymer are mixed together. In another embodiment, the thermosetting resin composition of the present disclosure is prepared by: about 3 to 20 parts by weight of the polymaleimide prepolymer, about 80 to 97 parts by weight of the poly (arylene ether), and then a solvent are mixed together in an amount sufficient to provide a concentration of solids in the solvent of at least 30% to no more than 90% solids. Once the thermosetting resin composition is prepared, it may then be coated onto an article or substrate and cured at a temperature greater than 150 ℃ to form a composite article.

The thermosetting resin compositions of the present disclosure can be used to prepare composite articles by techniques known in the industry (e.g., by pulverizing, molding, encapsulating, or coating). Due to their thermal properties, the thermosetting resin compositions of the present disclosure are particularly useful in preparing articles for continuous use applications at high temperatures. Examples include electrical laminates and electrical packages. Other examples include: molded powders, coatings, structural composite parts, such as fairings for aerospace applications, and gaskets.

In another aspect, the present disclosure provides a method for making a resin coated article. The method steps include contacting an article or substrate with the thermosetting resin composition of the present disclosure. The compositions of the present disclosure may be contacted with the article or substrate by any method known to those skilled in the art. Examples of such a contacting method include: powder coating, spray coating, spot coating (curing), roll coating, resin dipping methods, and contacting an article with a bath comprising the thermosetting resin composition. In one embodiment, the article or substrate is contacted with the thermosetting resin composition in a varnish bath. In another embodiment, the present disclosure provides articles or substrates, particularly prepregs and laminates, prepared by the methods of the present disclosure.

In yet another aspect, the present disclosure provides a prepreg obtained by impregnating a reinforcing material with the thermosetting resin composition of the present disclosure.

The present disclosure also provides a metal-clad foil obtained by coating a metal foil with the thermosetting resin composition of the present disclosure.

In yet another aspect, the present disclosure also provides a laminate having improved properties obtained by laminating the above prepreg and/or the above metal-clad foil.

The thermosetting resin composition of the present disclosure can be used to impregnate a reinforcing material, for example, glass cloth or quartz cloth, and cured into a product having heat resistance and/or low dielectric loss at high frequencies, so that the composition is suitable for preparing a laminate having well-balanced properties, very reliable with respect to electrical insulation and mechanical strength at high temperatures. Reinforcing materials or reinforcing materials that can be coated with the thermosetting resin compositions of the present disclosure include any material used by those skilled in the art to form composites, prepregs, and laminates. Examples of suitable substrates include fiber-containing materials such as woven fabrics, meshes, felts, fibers, and non-woven aramid reinforcements. Preferably, such materials are made of glass, fiberglass, quartz, paper which may be cellulosic or synthetic, thermosetting resin substrates such as aromatic polyamide reinforcement, polyethylene, poly (p-phenylene terephthalamide), polyester, polytetrafluoroethylene and poly (p-phenylene benzobisthiazole), syndiotactic polystyrene, carbon, graphite, ceramics or metals. Preferred materials include glass or glass fibers or quartz in the form of woven cloth or felt.

In one embodiment, the reinforcing material is contacted with a varnish bath comprising the thermosetting resin composition of the present disclosure dissolved and intimately mixed in a solvent or solvent mixture. The coating is performed under conditions such that the reinforcing material is coated with the thermosetting resin composition. The coated reinforcing material is then passed through a heated zone at a temperature sufficient to cause the solvent to evaporate but below a temperature at which the thermosetting resin composition undergoes substantial curing during the residence time of the heated zone.

The reinforcement preferably has a residence time in the bath of from 1 second to 300 seconds, more preferably from 1 second to 120 seconds, and most preferably from 1 second to 30 seconds. The temperature of such a bath is preferably from 0 ℃ to 100 ℃, more preferably from 10 ℃ to 40 ℃, and most preferably from 15 ℃ to 30 ℃. The residence time of the coated reinforcement material in the heating zone is preferably from 0.1 to 15 minutes, more preferably from 0.5 to 10 minutes, and most preferably from 1 to 5 minutes.

The temperature of this zone is sufficient to cause any residual solvent to evaporate, but not so high that the components fully cure during the residence time. Preferred temperatures in such regions are from 80 ℃ to 250 ℃, more preferably from 100 ℃ to 225 ℃, and most preferably from 150 ℃ to 210 ℃. Preferably, there is a means of removing the solvent in the heated zone, either by passing an inert gas through the oven, or by drawing a slight vacuum in the oven. In many embodiments, the coated material is exposed to an area of increasing temperature. The first region is designed to evaporate the solvent so that it can be removed. The latter region is designed to cause partial curing (B-staging) of the thermosetting resin component.

One or more sheets of prepreg are optionally processed into a laminate with one or more sheets of conductive material (e.g., copper). In such further processing, one or more segments or portions of the coated reinforcing material are brought into contact with each other and/or with the conductive material. The contacted portions are then exposed to elevated pressure and temperature sufficient to cause the components to cure, wherein the resin on adjacent portions reacts to form a continuous resin matrix between the reinforcing materials. The sections may be cut and stacked or folded and stacked as part of the desired thickness or shape prior to curing. The pressure used can be anywhere from 1psi to 1000psi, with 10psi to 800psi being preferred. The temperature used to cure the resin in the part or laminate depends on the specific residence time, the pressure used and the resin used. Preferred temperatures that may be used are from 100 ℃ to 250 ℃, more preferably from 120 ℃ to 220 ℃, and most preferably from 170 ℃ to 200 ℃. The residence time is preferably 10 minutes to 120 minutes, and more preferably 20 minutes to 90 minutes.

In one embodiment, the process is a continuous process, wherein the reinforcement material is removed from the oven, suitably configured to the desired shape and thickness, and pressed at very high temperatures for a short period of time. In particular, such high temperatures are from 180 ℃ to 250 ℃, more preferably from 190 ℃ to 210 ℃, for times ranging from 1 minute to 10 minutes, and from 2 minutes to 5 minutes. Such high speed pressing allows for more efficient use of processing equipment. In such embodiments, the preferred reinforcing material is a glass mesh or woven step.

In some embodiments, it is desirable to subject the laminate or final product to post-cure after pressing. This step is designed to complete the curing reaction. The post-curing is typically carried out at 130 ℃ to 220 ℃ for a period of 20 minutes to 200 minutes. This post-cure step may be performed in a vacuum to remove any components that may be volatilized.

In another aspect, the thermosetting resin composition, after mixing and curing, provides a cured product, e.g., a laminate, having very well-balanced properties. The properties of the cured product according to the present disclosure having a very well balanced balance include at least two of: a glass transition temperature (Tg) greater than about 170 ℃, preferably greater than about 175 ℃, and more preferably greater than about 180 ℃; at least V1, and preferably V0 for the flame retardancy rating of UL 94; a dielectric loss tangent of less than about 0.0034 at 5GHz, preferably less than about 0.005 at 16 GHz; and a dielectric constant of less than about 3.00 at 5GHz, preferably less than about 2.80 at 5GHz, and more preferably less than about 3.00 at 16GHz, and even more preferably less than about 2.70 at 16 GHz. In one aspect, the thermosetting resin composition is cured in a curing cycle comprising heating the composition at a temperature of about 120 ℃ for about 16 hours, then at a temperature of about 170 ℃ for about 1 hour, then at a temperature of about 200 ℃ for about 1 hour, then at a temperature of about 230 ℃ for about 1 hour, and finally at a temperature of about 250 ℃ for about 1 hour.

While various preparation and use embodiments of the disclosure have been described above in detail, it should be understood that this disclosure provides many applicable inventive concepts that can be embodied in a wide variety of contexts within this specification. The specific embodiments discussed in this application are merely illustrative of specific ways to make and use the disclosure, and do not delimit the scope of the disclosure.

Claims

1. A thermosetting resin composition comprising:

(a) a polymaleimide prepolymer obtained by a chain extension reaction of a polyimide and an alkenylphenol, alkenylphenol ether or a mixture thereof in the presence of an amine catalyst; and

(b) a poly (arylene ether) prepolymer obtained by a chain extension reaction of a poly (arylene ether) and an allylic monomer, optionally in the presence of a catalyst; characterized in that the resulting cured product formed by curing the thermosetting resin composition comprises at least two well-balanced properties of: (1) a glass transition temperature (Tg) greater than about 170 ℃; (2) a UL94 flame retardancy rating of at least V1; (3) a dielectric loss tangent of less than about 0.005 at 16GHz, and (4) a dielectric loss constant of less than about 3.00 at 16 GHz.

2. The thermosetting resin composition of claim 1, wherein the polyimide is a bismaleimide of the general formula:

wherein R is¹Is hydrogen or methyl; and X is-C_iH_2i-, where i =2 to 20, -CH₂CH₂SCH₂CH₂-, phenylene, naphthylene, xylylene, cyclopentylene, 1,5, 5-trimethyl-1, 3-cyclohexylene, 1, 4-bis- (methylene) -cyclohexylene, or a group of the formula:

wherein R is²And R³Independently methyl, ethyl or hydrogen, and Z is a direct bond, methylene, 2-propylene, -CO-, -O-, -S-, -SO-or-SO₂-。

3. The thermosetting resin composition of claim 2, wherein the poly (arylene ether) comprises one or more compounds comprising a plurality of structural units having the general formula:

wherein, for each structural unit, Q is¹Independently is primary or secondary C₁-C₁₂Hydrocarbyl radical, C₁-C₁₂Mercapto or C₁-C₁₂A hydrocarbyloxy group; and in each case Q²Independently is primary or secondary C₁-C₁₂Hydrocarbyl radical, C₁-C₁₂Hydrocarbyloxy or C₁-C₁₂A hydrocarbyloxy group.

4. The thermosetting resin composition of claim 2, wherein the poly (arylene ether) is a functionalized poly (arylene ether) selected from the group consisting of capped poly (arylene ether), di-capped poly (arylene ether), ring-functionalized poly (arylene ether), and poly (arylene ether) resins comprising at least one terminal functional group selected from the group consisting of carboxylic acid, glycidyl ether, vinyl ether, and anhydride.

5. The thermosetting resin composition of claim 1, wherein a catalyst is present during the chain extension reaction of the poly (arylene ether) and allyl monomer.

6. The thermosetting resin composition of claim 5, wherein the catalyst is a metal acetyl acetonate having the structure:

7. The thermosetting resin composition of claim 1, wherein the catalyst is a Grubbs catalyst.

8. The thermosetting resin composition of claim 1, further comprising a phosphorylated flame retardant.

9. The thermosetting resin composition of claim 1, further comprising an organic solvent.

10. A thermosetting resin composition comprising:

(a) 3 to 20 parts by weight of a polymaleimide prepolymer obtained by chain-extension reaction of a polyimide with an alkenylphenol, an alkenylphenol ether or a mixture thereof in the presence of an amine catalyst, based on 100 parts by weight of the thermosetting resin composition; and

(b) 80-97 parts by weight, based on 100 parts by weight of the thermosetting resin composition, of a poly (arylene ether) prepolymer obtained by a chain extension reaction of a poly (arylene ether) and an allyl monomer, optionally in the presence of a catalyst; characterized in that the resulting cured product formed by curing of the thermosetting resin composition comprises at least two well-balanced properties of: (1) a glass transition temperature (Tg) greater than about 170 ℃; (2) a UL94 flame retardancy rating of at least V1; (3) a dielectric loss tangent of less than about 0.005 at 16GHz, and (4) a dielectric loss constant of less than about 3.00 at 16 GHz.

11. The thermosetting resin composition of claim 9, wherein the amounts of poly (arylene ether) and allyl monomer contacted in the chain extension reaction comprise at least about 51-60 parts by weight of poly (arylene ether) and at least about 40-49 parts by weight of allyl monomer, based on 100 parts by weight of the chain extension reaction mixture.

12. A process for preparing a thermosetting resin composition comprising mixing together:

(b) 80-97 parts by weight, based on 100 parts by weight of the thermosetting resin composition, of a poly (arylene ether) prepolymer obtained by a chain extension reaction of a poly (arylene ether) and an allyl monomer, optionally in the presence of a catalyst; and optionally

(c) A phosphorylated flame retardant; and

(e) an organic solvent.

13. A thermosetting resin composition prepared according to the method of claim 11.

14. A method for preparing a coated article comprising: coating the article with the thermosetting resin composition of claim 1, and heating the article to cure the thermosetting resin composition.

15. A prepreg, comprising: (a) a woven fabric, and (b) the thermosetting resin composition according to claim 1.

16. The prepreg of claim 15, in which the woven fabric comprises fiberglass or quartz.

17. A laminate, comprising: (a) a substrate comprising the thermosetting resin composition of claim 1; and (b) a metal layer disposed on at least one surface of the substrate.

18. The laminate of claim 15, wherein the substrate further comprises a reinforcement of woven glass or quartz fabric, wherein the thermosetting resin composition is impregnated onto the woven glass or quartz fabric.

19. A Printed Circuit Board (PCB) prepared from the laminate of claim 15.

20. A fairing composite prepared from the laminate of claim 15.