Low-loss composite material layer and composition for forming the same

Abstract

In one aspect, the composition comprises: a hydrocarbon thermoplastic polymer containing repeating units derived from an α-olefin and a C4-30 cycloolefin; a reactive monomer that can be free-radically crosslinked to produce a crosslinked network; a free-radical source; and a functionalized fused silica capable of chemically coupling with the crosslinked network.

Description

[0001] Cross - reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application Serial No. 62 / 851,846, filed May 23, 2019. The related application is incorporated herein by reference in its entirety. Background of the Invention

[0003] This application relates to low - loss composite material layers. Laminates and prepreg systems for cellular telecommunications, laminate - based chip carriers, high - speed digital servers, etc. must meet many physical and electrical performance criteria, e.g., low loss, low dielectric constant, good heat resistance, good dimensional stability, etc. Such systems are constantly trending towards smaller components with higher performance requirements that need improvement at various levels. Thus, there is still a need for improved materials for circuit materials. Specifically, improvements are needed, e.g., including increased peel strength for very low - profile metal foils. Additional advantages include achieving further reduced dielectric loss values and other desired electrical, thermal, and physical properties. Summary of the Invention

[0004] Disclosed herein are low - loss dielectric layers and compositions for forming them.

[0005] In one aspect, the composition comprises a hydrocarbon - based thermoplastic polymer; a reactive monomer that can be free - radically cross - linked to produce a cross - linked network; a free - radical source; and functionalized fused silica capable of chemically coupling with the cross - linked network.

[0006] In another aspect, a composite material layer can be derived from the composition.

[0007] In one aspect, a method of manufacturing the composite material layer includes forming a layer from the composition; and polymerizing the reactive monomer in the composition to form a cross - linked network.

[0008] In another aspect, a multi - layer article includes the composite material layer.

[0009] The above and other features are illustrated by the following drawings, detailed description, and claims. Brief Description of the Drawings

[0010] The following drawings are exemplary aspects provided to illustrate the present disclosure. The drawings are illustrative embodiments and are not intended to limit the devices made in accordance with the present disclosure to the materials, conditions, or process parameters described herein.

[0011] Figure 1 is a graphical illustration of the minimum melt viscosity value and the coefficient of thermal expansion value versus the filler content;

[0012] Figure 2A scanning electron microscope of a composition of an embodiment containing fused silica; and

[0013] Figure 3 A scanning electron microscope of a composition of an embodiment containing methacrylated fused silica. Detailed Description

[0014] The dielectric composition for a bonding sheet layer of a multilayer printed circuit board needs to have a minimum melt viscosity low enough so that it can fully flow into and fill the surface topography associated with adjacent signal layers and / or ground layers, while maintaining a low coefficient of thermal expansion in the z-axis direction to ensure high reliability of the plated through holes. Since these two properties are generally completely opposite, it is difficult to achieve a dielectric composition with an optimal balance between the minimum melt viscosity and the coefficient of thermal expansion. Compositions for forming composite layers have been developed that can not only achieve a good balance between the minimum melt viscosity and the coefficient of thermal expansion, but also exhibit at least one of low loss or high peel strength to copper. The composition contains a hydrocarbon-based thermoplastic polymer; a reactive monomer that can be free-radically crosslinked to produce a crosslinked network; a free-radical source; and functionalized fused silica.

[0015] It has been found that the presence of functionalized fused silica in the composite layer has a greater peel strength to copper compared to a composite layer formed from the same composition, except that it contains fused silica without functionality. For example, the composite layer can achieve a high peel strength to copper of greater than or equal to 0.54 kilograms per centimeter (kg / cm). It has also been found that the presence of functionalized fused silica in the composite layer results in a lower average coefficient of thermal expansion in the z-direction, even in the absence of a reinforcing layer, compared to a composite layer formed from the same composition, except that it contains fused silica without functionality. In addition, with respect to the reinforcing layer, unlike the bonding sheet layer that requires weaving or non-woven reinforcement to be feasible, this composite layer also has the advantage that it can be non-reinforced and can be made relatively thin. In addition, the composite layer formed from the composition can exhibit a low dielectric loss at 10 gigahertz (GHz) of less than or equal to 0.0030.

[0016] The composition contains a hydrocarbon-based thermoplastic polymer. As used herein, the term "hydrocarbon-based thermoplastic polymer" refers to a polymer prepared by addition polymerization of at least one unsaturated hydrocarbon without heteroatoms. The hydrocarbon-based thermoplastic polymer can be non-reactive with other components of the composition. The hydrocarbon-based thermoplastic polymer can be derived from at least one of α-olefins or cyclic olefins. The α-olefins can include at least one C 2-20 olefin, such as ethylene, propylene, 1-butene, or 1-decene. The cyclic olefins can include at least one C 4-30Cyclic olefins, such as cyclobutene, cyclopentene, cycloheptene, cyclooctene, cyclodecene, norbornene, or other alkyl- or aryl-substituted norbornenes (e.g., 5-methyl-2-norbornene, 5-hexyl-2-norbornene, 5-phenyl-2-norbornene, 5-ethyl-2-norbornene, 4,5-dimethyl-2-norbornene, or exo-1,4,4a,9,9a,10-hexahydro-9,10(1',2')-ethanoanthracene (HBMN)). Additional cyclic olefins include tricyclic monomers (e.g., exo-dihydrodicyclopentadiene) or tetracyclic monomers (e.g., endo,exo-tetracyclododecene). Any remaining unsaturation on the hydrocarbon polymer can be removed by hydrogenation prior to incorporation into the composition.

[0017] The hydrocarbon thermoplastic polymer can have the formula (I),

[0018]

[0019] wherein R1, R2, and R3 can each independently be H, C 1-30 alkyl, or C 6-30 aryl; n can be from 0 to 3,500, or from 10 to 2,500, or from 100 to 1,000; and m can be from 1 to 5,300, or from 100 to 3,000, or from 1,000 to 3,000. R1 can be H, C 1-30 alkyl, or C 6-30 aryl, and R2 and R3 can each independently be H, C 1-23 alkyl, or C 6-23 aryl. The molar ratio of cyclic olefin (e.g., C 4-30 cyclic olefin) repeat units to α-olefin repeat units in the hydrocarbon thermoplastic polymer can be from 6:1 to 0.5:1, or from 6:1 to 1.5:1.

[0020] The cyclic olefin can contain a functional group, such as at least one of an alkyl group (e.g., methyl, ethyl, propyl, or butyl). The cyclic olefin can contain a cyclic alkyl functional group (e.g., bicyclo[2.2.1]hept-2-ene, 6-methylbicyclo[2.2.1]hept-2-ene, 5,6-dimethylbicyclo[2.2.1]-hept-2-ene, 1-methylbicyclo[2.2.1]hept-2-ene, 6-ethylbicyclo[2.2.1]hept-2-ene). The cyclic olefin can contain a tetracyclic alkyl functional group (e.g., tetracyclo[4.4.0.1 2,5 .1 7,10 -3-dodecene, 8-methyltetracyclo[4.4.0.1 2,5 .1 7,10 -3-dodecene, 8-ethyltetracyclo[4.4.0.1 2,5 .1 7,10-3-Dodecene, 8,9-dimethyltetracyclo[4.4.0.1 2,5 .1 7,10 -3-Dodecene, 8-methyl-9-ethyltetracyclo[4.4.0.1 2,5 .1 7 ,10 -3-Dodecene, or 8-stearyltetracyclo[4.4.0.1 2,5 .1 7,10 -3-dodecene). The cyclic olefin can include an aryl group (e.g., phenyl, tolyl, or naphthyl) or a heteroatom-containing group (e.g., nitrile or halogen). Based on the total weight of the hydrocarbon-based thermoplastic polymer, the functionalized cyclic olefin repeating unit can be present in the hydrocarbon-based thermoplastic polymer in an amount of 5 wt% to 45 wt%, or 35 wt% to 75 wt%, or 65 wt% to 85 wt%.

[0021] The α-olefin can include at least one of a functional group such as an alkyl group, an aryl group (e.g., phenyl, tolyl, or naphthyl), or a heteroatom-containing group (e.g., nitrile or halogen). Based on the total weight of the hydrocarbon-based thermoplastic polymer, the functionalized α-olefin repeating unit can be present in the hydrocarbon-based thermoplastic polymer in an amount of 55 wt% to 95 wt%, or 25 wt% to 65 wt%, or 15 wt% to 35 wt%.

[0022] A single-site catalyst (e.g., a highly active metallocene, a constrained geometry catalyst (CGC), a nickel or palladium diimine complex) used in combination with methylaluminoxane (MAO) or a borate / ester cocatalyst can effect the copolymerization of a cyclic olefin and an α-olefin (e.g., ethylene or propylene).

[0023] Based on the total volume of the composition, the composition can include 10 volume percent (vol%) to 90 volume percent (vol%), or 25 vol% to 75 vol%, or 30 vol% to 50 vol% of the hydrocarbon-based thermoplastic polymer. As used herein, when referring to the amount of a component in weight percent or volume percent based on the total volume of the composition, the amount is based on the total amount of solids (i.e., minus any solvent present) and is also based on the total amount minus any reinforcing fabric (e.g., woven or non-woven fabric) present. Based on polystyrene standards, the weight-average molecular weight of the hydrocarbon-based thermoplastic polymer can be 500 grams per mole (g / mol) to 105,000 g / mol, or 3,000 g / mol to 100,000 g / mol, or 20,000 g / mol to 90,000 g / mol, or 70,000 g / mol to 90,000 g / mol.

[0024] The composition comprises reactive monomers capable of crosslinking to produce a crosslinked network. The reactive monomers may comprise at least one of the following: diallyl compounds, triallyl compounds, divinyl compounds, trivinyl compounds, conjugated dienes, non-conjugated dienes, di(meth)acrylate compounds, or tri(meth)acrylate compounds. The reactive monomers may comprise at least one of the following: triallyl (iso)cyanurate, 1,9-decadiene, 1,7-octadiene, tris(2-hydroxyethyl)isocyanurate triacrylate (THEIC TA), or trimethylolpropane trimethacrylate (TMP TMA). The reactive monomers may include triallyl (iso)cyanurate. As used herein, triallyl (iso)cyanurate includes at least one of triallyl isocyanurate and triallyl cyanurate as represented by formula (2A) and formula (2B), respectively.

[0025]

[0026] Based on the total volume of the composition, the composition may comprise 1 vol% to 35 vol%, or 5 vol% to 25 vol%, or 5 vol% to 15 vol% of the reactive monomers. The volume ratio of the hydrocarbon-based thermoplastic polymer to the reactive monomers may be from 1:1 to 50:1, or 1:1 to 10:1, or 2:1 to 5:1.

[0027] The composition may comprise a radical source (also referred to herein as an initiator), such as a radical source that can be thermally activated. Examples of radical sources that can be thermally activated include peroxides, azo compounds (e.g., α,α'-azobis(isobutyronitrile)), redox initiators (e.g., a combination of a peroxide such as H2O2 and a ferrous salt), or azides (e.g., acetyl azide). The radical source may comprise at least one of a peroxide initiator, an azo initiator, a carbon-carbon initiator, a persulfate initiator, a hydrazine initiator, an acyl hydrazine initiator, or a halogen initiator. The radical source may comprise at least one of 2,3-dimethyl-2,3-diphenylbutane, 3,4-dimethyl-3,4-diphenylhexane, or 1,4-diisopropylbenzene. The radical source may include organic peroxides, for example, at least one of dicumyl peroxide, tert-butyl perbenzoate, α,α′-bis(tert-butylperoxy)diisopropylbenzene, or 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne.

[0028] The free radical source may include peroxides having a decomposition temperature of at least 50 degrees Celsius (°C). Examples of peroxides include ketone peroxides (e.g., methyl ethyl ketone peroxide or cyclohexanone peroxide), peroxyacetals (e.g., 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane or 2,2-bis(tert-butylperoxy)butane), hydroperoxides (e.g., tert-butyl hydroperoxide or 2,5-dimethylhexane-2,5-dihydroperoxide), dialkyl peroxides (e.g., dicumyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hex-3-yne, or α,α'-bis(tert-butylperoxy-m-isopropyl)benzene), diacyl peroxides (e.g., octanoyl peroxide or isobutyryl peroxide), or peroxycarbonates / salts (e.g., diperoxycarbonates / salts, such as bis(4-tert-butylcyclohexyl) diperoxycarbonate)).

[0029] Based on the total weight of the composition, the composition may contain from 0.01% to 10% by volume, or from 0.05% to 3% by volume, or from 0.1% to 2% by volume, or from 0.5% to 1% by volume of the free radical source.

[0030] The composition contains functionalized fused silica. Based on the total volume of the composition, the composition may contain from 10% to 70% by volume, or from 20% to 60% by volume, or from 40% to 55% by volume, or from 10% to 40% by volume of functionalized fused silica. The functionalized fused silica may have a spherical morphology with an average diameter of from 1 micron to 50 microns, or from 1 micron to 10 microns.

[0031] The composition may contain a hydrocarbon-based thermoplastic polymer containing repeating units derived from an α-olefin and a C 4-30 cycloolefin; a reactive monomer that can be free-radically crosslinked to produce a crosslinked network; a free radical source; and functionalized fused silica capable of chemically coupling with the crosslinked network. The hydrocarbon-based thermoplastic polymer may contain repeating units derived from at least one of the following: cyclobutene, cyclopentene, cycloheptene, cyclooctene, cyclodecene, norbornene, or an alkyl- or aryl-substituted norbornene (e.g., 5-methyl-2-norbornene, 5-hexyl-2-norbornene, 5-phenyl-2-norbornene, 5-ethyl-2-norbornene, 4,5-dimethyl-2-norbornene, exo-1,4,4a,9,9a,10-hexahydro-9,10(1',2')-bridged-phenylene-1,4-methanoanthracene, exo-dihydrodicyclopentadiene, or endo,exo-tetracyclododecene). The hydrocarbon-based thermoplastic polymer may have the formula (I). C 4-30The molar ratio of the cycloolefin repeating unit to the α-olefin repeating unit can be from 6:1 to 0.5:1, or from 6:1 to 1.5:1. Based on polystyrene standards, the weight-average molecular weight of the hydrocarbon thermoplastic polymer can be from 500 grams per mole to 105,000 grams per mole. The reactive monomer can include triallyl (iso)cyanurate. The free radical source can include at least one of the following: dicumyl peroxide, dimethyldiphenylhexane, methyl ethyl ketone peroxide, cyclohexanone peroxide, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 2,2-bis(tert-butylperoxy)butane, tert-butyl hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hex-3-yne, tert-butyl perbenzoate, α,α'-di-(tert-butylperoxy)diisopropylbenzene, or 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne, α,α'-bis(tert-butylperoxy-m-isopropyl)benzene, octanoyl peroxide, isobutyryl peroxide, peroxydicarbonate / ester, α,α'-azobis(isobutyronitrile), redox initiator, acetyl azide, 2,3-dimethyl-2,3-diphenylbutane, 3,4-dimethyl-3,4-diphenylhexane, or 1,4-diisopropylbenzene. The composition can contain a hydrocarbon resin diluent. Based on polystyrene standards, the weight-average molecular weight of the hydrocarbon resin diluent can be from 200 grams per mole to 2,000 grams per mole. The hydrocarbon resin diluent can be derived from piperylene and optionally aromatic repeating units. The hydrocarbon resin diluent can be saturated. The composition can contain a flame retardant. The functional group of the functionalized fused silica can contain at least one of (meth)acrylate group, vinyl group, allyl group, propargyl group, butenyl group, or styryl group.

[0032] Based on the total volume of the composition, the composition may comprise from 10 volume percent to 90 volume percent, or from 25 volume percent to 75 volume percent, or from 30 volume percent to 50 volume percent of a hydrocarbon-based thermoplastic polymer. Based on the total weight of the composition, the composition may comprise from 0.1 volume percent to 2 volume percent, or from 0.5 volume percent to 1 volume percent of a free radical source. Based on the total volume of the composition, the composition may comprise from 1 volume percent to 35 volume percent, or from 5 volume percent to 25 volume percent, or from 5 volume percent to 15 volume percent of a reactive monomer. Based on the total volume of the composition, the composition may comprise from 10 volume percent to 70 volume percent, or from 20 volume percent to 60 volume percent, or from 40 volume percent to 55 volume percent of functionalized fused silica. Based on the total volume of the composition, the composition may comprise from 0 volume percent to 50 volume percent, or from 10 volume percent to 40 volume percent, or from 5 volume percent to 30 volume percent of a hydrocarbon resin diluent. Based on the total volume of the composition, the composition may comprise from 5 volume percent to 25 volume percent, or from 8 volume percent to 20 volume percent of a flame retardant.

[0033] Functionalized fused silica can be prepared by reacting a silane containing a functional group. The functional group can include at least one of (meth)acrylate group, vinyl group, allyl group, propargyl group, butenyl group, or styryl group. Examples of (meth)acrylate-functionalized silanes include (3-acryloxypropyl)trimethoxysilane, n-(3-acryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane, (3-acryloxypropyl)methyldimethoxysilane, methacryloxypropyltrimethoxysilane, o-(methacryloxyethyl)-n-(triethoxysilylpropyl)carbamate, n-(3-methacryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane, methacryloxymethyltriethoxysilane, methacryloxymethyltrimethoxysilane, methacryloxypropyltriethoxysilane, (methacryloxymethyl)methyldiethoxysilane, (methacryloxymethyl)methyldimethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylethoxysilane, or methacryloxypropyldimethylmethoxysilane. Examples of vinyl-functionalized silanes include vinyltriacetoxysilane, vinyltriethoxysilane, vinyltriisopropenyloxysilane, vinyltriisopropoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, vinyltris(methylethylketoxime)silane, (divinylmethylsilylethyl)triethoxysilane, docosenyltriethoxysilane, hexadecafluorododec-11-enyl-1-trimethoxysilane, hexenyltriethoxysilane, 7-octenyltrimethoxysilane, 0-undecenyltrimethoxysilane, o-(vinyloxybutyl)-n-(triethoxysilylpropyl)carbamate, vinyltri-tert-butoxysilane, vinyltris(methoxypropoxy)silane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, vinyldimethylethoxysilane, trivinylmethoxysilane, bis(triethoxysilylethyl)vinylmethylsilane, triethoxysilyl-modified poly-1,2-butadiene, or diethoxymethylsilyl-modified poly-1,2-butadiene. Examples of allyl-functionalized silanes include 3-(n-allylamino)propyltrimethoxysilane, n-allyl-aza-2,2-dimethoxysilacyclopentane, allyltrimethoxysilane, allyloxyundecyltrimethoxysilane, allyltriethoxysilane, or 2-(chloromethyl)allyltrimethoxysilane. Examples of propargyl-functionalized silanes include o-(propargyloxy)-n-(triethoxysilylpropyl)carbamate. Examples of butenyl-functionalized silanes include butenyltriethoxysilane. Examples of styryl-functionalized silanes include 3-(n-styrylmethyl-2-aminoethylamino)propyltrimethoxysilane or styrylethyltrimethoxysilane.Examples of cyclopentadienyl-functionalized silanes include (3-cyclopentadienylpropyl)trimethoxysilane. Examples of cyclohexenyl-functionalized silanes include [2-(3-cyclohexenyl)ethyl]trimethoxysilane or [2-(3-cyclohexenyl)ethyl]triethoxysilane. The functionalized silane can include a methacryloyl silane, such as at least one of γ-methacryloyloxypropylmethyldimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylmethyldiethoxysilane, or γ-methacryloyloxypropyltriethoxysilane.

[0034] The composition can contain a hydrocarbon resin diluent. The hydrocarbon resin diluent can include an amorphous thermoplastic oligomer or polymer produced by the polymerization of unsaturated hydrocarbons. As used herein, based on polystyrene standards, the weight-average molecular weight of the hydrocarbon resin diluent oligomer can be less than or equal to 2,500 g / mol. The hydrocarbon resin diluent can produce at least one of a reduced minimum melt viscosity, enhanced resin flow, or improved leveling.

[0035] The hydrocarbon resin diluent can include C 2-9 hydrocarbon resin diluent. The hydrocarbon resin diluent can be derived from at least one of aliphatic C 2-9 hydrocarbons or aromatic C 6-9 hydrocarbons. The hydrocarbon resin diluent can be saturated. The hydrocarbon resin diluent can be free of (or can contain 0 mole percent of) repeating units derived from C 5-25 cycloolefins. The hydrocarbon resin diluent can contain repeating units derived from cyclooctene.

[0036] The hydrocarbon resin diluent can include polybutene (e.g., oligomeric polybutene). Oligomers of C4 olefins (primarily isobutene) are commercially available over a wide range of weight-average molecular weights. Polybutene with a short chain length is free-flowing; polybutene with a medium chain length is viscous, having a honey-like consistency, while polybutene with the longest chain length is a very sticky semi-solid. Examples of polybutene include INDOPOL available from INEOS Oligomers, London TM and PANALANE available from Vantage Specialty Ingredients, Inc., Warren, NJ TM .

[0037] Hydrocarbon resin diluents can include C5 hydrocarbon resin diluents that can be prepared from at least one of piperylene or its derivatives (such as cis / trans 1,3-pentadiene, 2-methyl-2-butene, cyclopentene, cyclopentadiene (CPD), or dicyclopentadiene (DCPD)). Piperylene monomers and their derivatives can be cationically polymerized using a Lewis acid catalyst to produce oligomeric resins with low to high softening points. C5 hydrocarbon resin diluents can be predominantly aliphatic and can thus be compatible with at least one of the following: natural rubber, styrene-isoprene-styrene (SIS) copolymers, amorphous polyolefins (APO) (such as amorphous polyalpha-olefins (APAO)), polyolefins (such as low-density polyethylene (LDPE)), many synthetic elastomers, or low-polarity cyclic olefin copolymers (COC). Based on polystyrene standards, the weight-average molecular weight of the C5 hydrocarbon resin diluent can be from 200 grams per mole (g / mol) to 2,500 grams per mole (g / mol). The softening point of the C5 hydrocarbon resin diluent can be from 85 °C to 115 °C (solid grade) or from 5 °C to 10 °C (liquid grade). The C5 hydrocarbon resin diluent can be hydrogenated to reduce discoloration and improve thermal oxidative stability and UV stability. Examples of C5 hydrocarbon resin diluents are WINGTACK TM 10, WINGTACK TM 95 and WINGTACK TM 98.

[0038] Hydrocarbon resin diluents can include C 8-9 hydrocarbon resin diluents, such as those containing aromatic repeating units. C 8-9 Hydrocarbon resin diluents can be prepared from coal tar or crude oil distillates such as indene, methylindene, styrene, methylstyrene (such as α-methylstyrene), or vinyltoluene. Aromatic C 8-9 hydrocarbon monomers can be cationically polymerized using a Lewis acid catalyst to produce oligomeric resins within a weight-average molecular weight range. Compared to C5 hydrocarbon resin diluents, aromatic C 8-9 hydrocarbon resin diluents can have higher melt viscosities and softening points (100 °C to 150 °C). Aromatic C 8-9 hydrocarbon resin diluents are also compatible with a variety of polymers.

[0039] Hydrocarbon resin diluents can contain both C5 resin diluents and C 8-9 hydrocarbon resin diluents, for example as their blends or copolyoligomers or copolymers. Based on the total weight of the diluent, C5 and C 8-9A composition of hydrocarbon resin diluent (such as as a blend or copolymer) may contain from 0 weight percent (wt%) to 50 weight percent (wt%), or 1 wt% to 50 wt%, or 5 wt% to 25 wt% of aromatic repeating units. Aromatic C 8-9 Examples of modified C5 hydrocarbon resin diluents are Wingtack available from Cray Valley, Exton, PA TM STS, Wingtack TM Extra and Wingtack TM 86.

[0040] The hydrocarbon resin diluent may include a blend or copolymerized oligomer or copolymer of any disclosed hydrocarbon resin diluent. For example, the hydrocarbon resin diluent may include copolymerized oligomers or copolymers derived from petroleum-based raw materials such as at least one of aliphatic C5, aromatic C9, styrene, ethylene, propylene, or butadiene. The hydrocarbon resin diluent may include at least one of styrene-ethylene-butadiene-styrene copolymer or styrene-propylene-butadiene-styrene copolymer; which may optionally be hydrogenated. An example of such a hydrocarbon resin diluent is REGALREZ available from Eastman TM resin.

[0041] The hydrocarbon resin diluent may include a crosslinkable elastomer. The crosslinkable elastomer may be derived from at least one of olefins (such as, for example, C 2-8 olefins such as ethylene, propylene, butene, butadiene, piperylene, or isoprene) or cycloolefins (such as, for example, norbornene-type monomers containing unsaturated side groups such as 5-vinyl-2-norbornene), provided that the crosslinkable elastomer contains at least one of unsaturation in the main chain or unsaturated side groups. An example of a crosslinkable elastomer is a crosslinkable elastomer derived from ethylene, propylene, and dicyclopentadiene. If the composition contains a crosslinkable elastomer containing repeating units derived from cycloolefins, its difference from a hydrocarbon-based thermoplastic polymer may be that the hydrocarbon-based thermoplastic polymer may not contain crosslinkable groups or the crosslinkable elastomer may have a lower weight-average molecular weight. For example, based on polystyrene standards, the weight-average molecular weight of the crosslinkable elastomer may be from 500 g / mol to 50,000 g / mol, or 500 g / mol to 10,000 g / mol, or 200 g / mol to 2,500 g / mol, and the weight-average molecular weight of the hydrocarbon-based thermoplastic polymer may be from 70,000 g / mol to 105,000 g / mol. An example of a crosslinkable ethylene-propylene-dicyclopentadiene elastomer is TRILENE available from Lion Elastomers, Geismar, LA TM 65D.

[0042] The differences between hydrocarbon resin diluents and hydrocarbon-based thermoplastic polymers can lie in at least one of the following: 1) The diluent can have a lower weight-average molecular weight. For example, the weight-average molecular weight of the diluent can be less than or equal to 60% of the weight-average molecular weight of the hydrocarbon resin diluent; 2) The diluent can have a lower heat distortion temperature point; 3) The diluent can have a lower glass transition temperature; or 4) The diluent can be reactive. One or more of these distinguishing features can enable the hydrocarbon resin diluent to plasticize the hydrocarbon-based thermoplastic polymer and its ceramic-filled forms, thereby enhancing resin flow and reducing the minimum melt viscosity of the formulated system.

[0043] Based on polystyrene standards, the weight-average molecular weight of the hydrocarbon resin diluent can be from 200 g / mol to 2,500 g / mol, or from 1,000 g / mol to 2,200 g / mol, or from 1,000 g / mol to 8,000 g / mol. Based on polystyrene standards, the number-average molecular weight of the hydrocarbon resin diluent can be from 150 g / mol to 6,000 g / mol, or from 200 g / mol to 2,200 g / mol. Based on the total volume of the composition, the composition can contain from 0 vol% to 50 vol%, or from 10 vol% to 40 vol%, or from 5 vol% to 30 vol% of the hydrocarbon resin diluent.

[0044] The composition can be free of a reinforcing layer. For example, the composition can be free of woven or non-woven fabrics. As used herein, the composition being free of a reinforcing layer can mean that it contains 0 wt% of the reinforcing layer.

[0045] The composition can include a reinforcing layer. The reinforcing layer can comprise multiple fibers, and the multiple fibers can help control the in-plane shrinkage of the composition during curing and can provide increased mechanical strength relative to the same composite layer without a reinforcing layer. The reinforcing layer can be a woven layer or a non-woven layer. The fibers can include at least one of the following: glass fibers (such as E-glass fibers, S-glass fibers, and D-glass fibers), silica fibers, polymer fibers (such as polyetherimide fibers, polysulfone fibers, poly(ether ketone) fibers, polyester fibers, polyethersulfone fibers, polycarbonate fibers, aramid fibers, or liquid crystal polymer fibers such as VECTRAN commercially available from Kuraray). The diameter of the fibers can be from 10 nanometers to 10 micrometers. The thickness of the reinforcing layer can be less than or equal to 200 micrometers, or from 50 micrometers to 150 micrometers. The composite layer can constitute from 5 volume percent to 15 volume percent, or from 6 volume percent to 10 volume percent, or from 7 volume percent to 11 volume percent, or from 7 volume percent to 9 volume percent of the composite layer plus the reinforcing layer.

[0046] The composition may comprise an additive, for example, at least one of a ceramic filler other than functionalized fused silica, a flame retardant, a colorant (such as a fluorescent dye or pigment), a plasticizer, a cure retarder, a cure promoter, an impact modifier, an antioxidant, or a UV protector.

[0047] The additive may include a filler other than functionalized fused silica. The filler may include at least one of the following: fused silica (such as hydrophobic fused silica), non-functionalized fused silica, titanium dioxide, barium titanate, strontium titanate, corundum, wollastonite, Ba2Ti9O 20 , zirconium tungstate, hollow ceramic spheres, boron nitride, aluminum nitride, silicon carbide, beryllium oxide, aluminum oxide, aluminum trihydroxide, magnesium oxide, mica, talc, nanoclay, or magnesium hydroxide. The filler may include at least one of solid glass spheres, hollow glass spheres, or core-shell rubber spheres. The D90 particle size of the ceramic filler may be from 0.1 micrometer to 10 micrometers, or from 0.5 micrometer to 5 micrometers. The D90 particle size of the filler may be less than or equal to 2 micrometers, or from 0.1 micrometer to 2 micrometers. Based on the total weight of the composition or composite layer, the filler may be present in an amount of 0.1 wt% to 10 wt%, or 0.1 wt% to 5 wt%.

[0048] The additive may include a thermal conductive filler. Examples of the thermal conductive filler include aluminum nitride, boron nitride, silicon carbide, diamond, nanodiamond, graphite, beryllium oxide, zinc oxide, zirconium silicate, magnesium oxide, silica, or aluminum oxide.

[0049] The additive may include a flame retardant. Based on the total volume of the composition, the composition may contain 5 vol% to 25 vol%, or 8 vol% to 20 vol% of the flame retardant. The flame retardant may include, for example, a metal hydrate having a volume average particle size of 1 nanometer (nm) to 500 nanometers (nm), or 1 nm to 200 nm, or 5 nm to 200 nm, or 10 nm to 200 nm; or the volume average particle size may be from 500 nm to 15 micrometers, for example, from 1 micrometer to 5 micrometers. The metal hydrate may include a hydrate of a metal such as at least one of Mg, Ca, Al, Fe, Zn, Ba, Cu, or Ni. Hydrates of Mg, Al, or Ca may be used, such as at least one of aluminum hydroxide, magnesium hydroxide, calcium hydroxide, iron hydroxide, zinc hydroxide, copper hydroxide, nickel hydroxide; or hydrates of calcium aluminate, gypsum dihydrate, zinc borate, zinc stannate, or barium metaborate. Complexes of these hydrates may be used, for example, a hydrate containing at least one of Ca, Al, Fe, Zn, Ba, Cu, or Ni and Mg. The complex metal hydrate may have the formula MgM x (OH) y, where M is Ca, Al, Fe, Zn, Ba, Cu or Ni, x is from 0.1 to 10, and y is from 2 to 32. The flame retardant particles can be coated or otherwise treated to improve dispersibility and other properties. The flame retardant can be reactive. The flame retardant can optionally include organic halogenated flame retardants such as chlorendic acid (HET acid), tetrabromophthalic acid, or dibromoneopentyl glycol. The flame retardant can optionally include non-halogenated flame retardants (such as melamine cyanurate), phosphorus-containing compounds (such as hypophosphite / salt, diphosphite / salt, phosphazene, vinyl-phosphazene, phosphonate / salt, phosphaphenanthrene oxide, fine particle size melamine polyphosphate, or phosphate / salt), polyhedral oligomeric silsesquioxane, or siloxane. The flame retardant can include brominated flame retardants. The brominated flame retardant can include at least one of bis(pentabromophenyl)ethane, ethylenebis(tetrabromophthalimide), tetradecabromodiphenoxybenzene, decabromodiphenyl ether, or brominated polyhedral oligomeric silsesquioxane. The flame retardant can be used in combination with a synergist. For example, a halogenated flame retardant can be used in combination with a synergist such as antimony trioxide.

[0050] The composition can include a reinforcing layer, such as a fibrous layer. The fibrous layer can be woven or non-woven, such as a felt. The fibrous layer can contain at least one of glass fibers or polymer-based fibers. Such a thermally stable fiber reinforcement can reduce the shrinkage in the plane of the substrate of a layer containing the composition upon curing. In addition, the use of the reinforcing layer can help impart relatively high mechanical strength to the substrate.

[0051] The glass fibers can include at least one of E glass fibers, S glass fibers, or D glass fibers. The polymer-based fibers can include high-temperature polymer fibers. The polymer-based fibers can contain liquid crystal polymers, such as VECTRAN commercially available from Kuraray TM . The polymer-based fibers can contain at least one of polyetherimide, polyether ketone, polysulfone, polyethersulfone, polycarbonate or polyester.

[0052] The composition can be solvated with an organic solvent (e.g., in a solution comprising at least one of toluene or xylene), cast horizontally onto a release liner, and dried to form a composite material layer. It should be noted that the amounts of the various components described relative to the composition can be directly related to the composite material layer. For example, a composition comprising 10 vol% to 50 vol% of a hydrocarbon-based thermoplastic polymer based on the total volume of the composition can correspond to a composite material layer comprising 10 vol% to 50 vol% of a hydrocarbon-based thermoplastic polymer based on the total volume of the composite material layer. The surface energy of the release liner can be from 40 dynes per centimeter to 50 dynes per centimeter. The release liner can comprise at least one of biaxially oriented polypropylene (BOPP) or polyester (e.g., poly(ethylene terephthalate)). The release liner can include at least one of a silicone-treated liner (e.g., polyester or glassine paper).

[0053] The composite material layer can be prepared by impregnating a reinforcing layer with the composition and an optional solvent. The impregnation can include at least one of the following: coating the composition onto the reinforcing layer (e.g., by at least one of casting, dip coating, spraying, knife over roll coating, knife over plate coating, coating via a metering rod, flow coating, roll coating, or reverse roll coating); curing the composition to form the composite material layer; and optionally drying after impregnation.

[0054] A method of forming a composite material layer can include forming a layer from the composition and polymerizing reactive monomers in the composition to form a crosslinked network. The polymerization can include polymerizing reactive monomers and functionalized fused silica to form a crosslinked network. Additionally, polymerizing to form a crosslinked network in the composite material layer can further include polymerizing a reactive hydrocarbon resin diluent, if present.

[0055] The polymerization can include at least one of raising the temperature of the composite material layer (e.g., by laminating) or exposing the composite material layer to electron beam irradiation. Laminating may require laminating a layered structure comprising a multi-layer stack, the multi-layer stack including the composite material layer itself or a composite material layer located between two outer layers. The multi-layer stack can include multiple alternating layers of the composite material layer and a base layer. The multi-layer stack can then be placed in a press (e.g., a vacuum press) at a certain pressure and temperature for a certain duration, the pressure, temperature, and duration being suitable for forming a crosslinked network within the composite material layer located between the base layers. The multi-layer stack can be roll-to-roll laminated or treated under high pressure.

[0056] Laminating and curing can be carried out by a one-step method, for example using a vacuum press, or can be carried out by a multi-step method. In the one-step method, the stack to be laminated can be placed in the press, raised to the lamination pressure and heated to the lamination temperature. The lamination temperature can be 100 °C to 390 °C, or 100 °C to 250 °C, or 100 °C to 200 °C, or 100 °C to 175 °C, or 150 °C to 170 °C. The lamination pressure can be 1 megapascal (MPa) to 3 megapascals (MPa), or 1 MPa to 2 MPa, or 1 MPa to 1.5 MPa. The lamination temperature and pressure can be maintained for a desired dwell (holding) time, for example, 5 minutes to 150 minutes, or 5 minutes to 100 minutes, 10 minutes to 50 minutes, and then cooled, optionally at a controlled cooling rate (under the applied pressure or without the applied pressure) to, for example, less than or equal to 150 °C.

[0057] Circuit materials including composite material layers can be prepared by forming a multi-layer material having a composite material layer and a conductive layer provided thereon. Useful conductive layers include at least one of, for example, stainless steel, copper, gold, silver, aluminum, zinc, tin, lead, or transition metals. There is no particular limitation on the thickness of the conductive layer, nor any limitation on the shape, size or surface texture of the conductive layer. The thickness of the conductive layer can be 3 micrometers to 200 micrometers, or 9 micrometers to 180 micrometers. When there are two or more conductive layers, the thicknesses of the two layers can be the same or different. The conductive layer can include a copper layer. Suitable conductive layers include thin layers of conductive metals, such as copper foils currently used to form circuits, such as electrodeposited copper foils. The root mean squared (RMS) roughness of the copper foil can be less than or equal to 2 micrometers, or less than or equal to 0.7 micrometers, where the roughness is measured using a stylus profilometer.

[0058] The conductive layer can be applied by: laminating the conductive layer and the composite material layer, by direct laser structuring, or by adhering the conductive layer to the substrate via an adhesive layer. Other methods known in the art can be used to apply the conductive layer, such as electrodeposition, chemical vapor deposition, etc., where permitted by the specific materials and forms of the circuit materials.

[0059] Laminating may involve laminating a multi-layer stack including a composite material layer, a conductive layer, and an optional intermediate layer between the composite material layer and the conductive layer to form a layered structure. The conductive layer can be in direct contact with the composite material layer without an intermediate layer. Then, the layered structure can be placed in a press (e.g., a vacuum press) at a certain pressure and temperature for a certain duration, where the pressure, temperature, and duration are suitable for bonding the layers and forming a laminate. Laminating and optional curing can be carried out by a one-step method, such as using a vacuum press, or can be carried out by a multi-step method. In the one-step method, the layered structure can be placed in the press, raised to the lamination pressure (e.g., 1.0 MPa to 8.3 MPa) and heated to the lamination temperature (e.g., 260 °C to 390 °C). The lamination temperature and pressure can be maintained for a desired holding time, such as 20 minutes, and then cooled (while still under pressure) to less than or equal to 150 °C.

[0060] If present, the intermediate layer can include a polyfluorocarbon film that can be located between the conductive layer and the composite material layer, and optionally a microglass-reinforced fluorocarbon polymer layer can be located between the polyfluorocarbon film and the conductive layer. The microglass-reinforced fluorocarbon polymer layer can increase the adhesion of the conductive layer to the substrate. Based on the total weight of the layer, the microglass can be present in an amount of 4 weight percent (wt%) to 30 weight percent (wt%). The longest length scale of the microglass can be less than or equal to 900 micrometers, or less than or equal to 500 micrometers. The microglass can be of the type commercially available from Johns-Manville Corporation, Denver, Colorado. The polyfluorocarbon film contains a fluoropolymer (e.g., polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, and a copolymer having a tetrafluoroethylene backbone and a fully fluorinated alkoxy side chain).

[0061] The conductive layer can be applied by laser direct structuring. Here, the composite material layer can contain laser direct structuring additives; laser direct structuring can include irradiating the surface of the substrate with a laser to form a track of the laser direct structuring additives and applying a conductive metal to the track. The laser direct structuring additives can include metal oxide particles (e.g., titanium oxide and copper chromite oxide). The laser direct structuring additives can include spinel-based inorganic metal oxide particles, such as spinel copper. The metal oxide particles can be coated, for example, with a composition containing tin and antimony (e.g., 50 wt% to 99 wt% tin and 1 wt% to 50 wt% antimony based on the total weight of the coating). Based on 100 parts of the respective composition, the laser direct structuring additives can contain 2 parts to 20 parts of the additives. Irradiation can be carried out with a YAG laser having a wavelength of 1,064 nanometers at an output power of 10 watts, a frequency of 80 kilohertz (kHz), and a rate of 3 meters per second. The conductive metal can be applied using a plating process in an electroless plating bath containing, for example, copper.

[0062] The conductive layer can be applied by adhesively applying the conductive layer. The conductive layer can be a circuit (a metallization layer of another circuit), such as a flexible circuit. An adhesive layer can be provided between the one or more conductive layers and the composite material layer.

[0063] The composite material layer can be used to adhere to one or more base layers, such as two base layers. Each base layer can independently include at least one of the following: fluoropolymer (such as polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), perfluoroalkoxy alkane (PFA)), polyimide (such as Kapton TM )), liquid crystal polymer (LCP, such as VECTRAN TM ), polyester, polyamide, polyolefin, polyphenylene ether, or conductive metal. The conductive metal can include at least one of silver, nickel, gold, cobalt, copper, or aluminum. The surface roughness (Rz) of the conductive metal can be less than 10 microns, or be 1 micron to 10 microns.

[0064] Due to the formation of the crosslinked network, the composite material layer formed from the compositions disclosed herein can exhibit thermosetting characteristics. During the polymerization of the crosslinked network, the viscosity and temperature can be determined when the film begins to soften into a minimum melt and before the crosslinking agent begins to increase the molecular weight, and this is taken as the minimum melt viscosity of the composition at the corresponding temperature. The minimum melt viscosity of the composition determined by parallel plate oscillatory rheology at a heating rate of 5 °C per minute can be greater than or equal to 80 kilopascals (kPa), or be 80 kPa to 700 kPa.

[0065] The peel strength of the composite material layer to copper measured according to IPC test method 650, 2.4.8 can be greater than or equal to 0.54 kg / cm, or be 0.65 kg / cm to 1.1 kg / cm.

[0066] The average coefficient of thermal expansion in the z-direction of the composite material layer at 150 °C to 250 °C can be less than or equal to 95 parts per million per degree Celsius (ppm / °C), or less than or equal to 90 ppm / °C, and can be determined using a 1 mil (0.0254 millimeters (mm)) thick sample by ASTM D3386-00 at -125 °C to 20 °C.

[0067] The dielectric constant of the composite material layer at 10 GHz can be from 2.5 to 3.5. The dielectric loss of the composite material layer at 10 GHz can be less than or equal to 0.0030, or less than or equal to 0.0021, or from 0.001 to 0.0025. The dielectric loss and the dielectric constant can be measured at a temperature of 23°C to 25°C according to the "Stripline Test for Permittivity and Loss Tangent at X-Band" test method (IPC-TM-650 2.5.5.5).

[0068] The composite material layer can have a UL94 V0 rating at a thickness from 84 microns to 760 microns as determined by Underwriter’s Laboratory UL 94 safety standard "Tests for Flammability of Plastic Materials for Parts in Devices and Appliances".

[0069] The article can include the composite material layer. The article can be a printed circuit board. The article can include a metal foil (such as copper) coated with the composite material layer composition. The article can be used for cellular telecommunications. The article can be a laminate-based chip carrier. The article can be used for high-speed digital applications.

[0070] In summary, in one aspect, the low-loss composition comprises: 10 volume percent to 90 volume percent, or 25 volume percent to 75 volume percent, or 30 volume percent to 50 volume percent of a hydrocarbon-based thermoplastic polymer, the hydrocarbon-based thermoplastic polymer comprising a moiety derived from an alpha-olefin and C 4-30Repeat units of cycloolefins, preferably repeat units derived from at least one of the following: cyclobutene, cyclopentene, cycloheptene, cyclooctene, cyclodecene, norbornene, or norbornene substituted with an alkyl or aryl group (such as 5-methyl-2-norbornene, 5-hexyl-2-norbornene, 5-phenyl-2-norbornene, 5-ethyl-2-norbornene, 4,5-dimethyl-2-norbornene, exo-1,4,4a,9,9a,10-hexahydro-9,10(1',2')-ethanoanthracene, exo-dihydrodicyclopentadiene, or endo,exo-tetracyclododecene), more preferably wherein the hydrocarbon thermoplastic polymer has the formula (I) as described herein, and wherein based on polystyrene standards, the weight average molecular weight of the hydrocarbon thermoplastic polymer is from 500 grams per mole to 105,000 grams per mole; from 1 volume percent to 35 volume percent, or from 5 volume percent to 25 volume percent, or from 5 volume percent to 15 volume percent of a reactive monomer that can be free-radically crosslinked to produce a crosslinked network, preferably triallyl (iso)cyanurate; an effective amount of a free-radical source, such as a peroxide; and from 10 volume percent to 70 volume percent, or from 20 volume percent to 60 volume percent of a functionalized fused silica that can chemically couple to the crosslinked network, preferably wherein the functional group is at least one of (meth)acrylate, vinyl, allyl, propargyl, butenyl, or styryl, and the functionalized fused silica has a spherical morphology with an average diameter of from 1 micron to 50 microns, or from 1 micron to 10 microns. Optionally, there may be present from 0 volume percent to 50 volume percent, or from 10 volume percent to 40 volume percent, or from 5 volume percent to 30 volume percent of a hydrocarbon resin diluent having a weight average molecular weight of from 200 grams per mole to 2,000 grams per mole based on polystyrene standards, preferably wherein the hydrocarbon resin diluent is derived from piperylene and optional aromatic repeat units; wherein the hydrocarbon resin diluent is optionally saturated. Optionally, based on the total volume of the composition, there may be present from 5 volume percent to 25 volume percent, or from 8 volume percent to 20 volume percent of a flame retardant.

[0071] The composite layer derived from the foregoing composition may have a minimum melt viscosity of greater than or equal to 80 kilopoise, or from 80 kilopoise to 700 kilopoise; a peel strength to copper of greater than or equal to 0.54 kilograms per centimeter; an average coefficient of thermal expansion in the z-direction at 150 °C to 250 °C of less than or equal to 95 parts per million per degree Celsius, or less than or equal to 90 parts per million per degree Celsius; a dielectric constant at 10 gigahertz of from 2.5 to 3.5; and a dielectric loss at 10 gigahertz of less than or equal to 0.0030, or less than or equal to 0.0021, or from 0.001 to 0.0025. Multilayer articles are disclosed that include a composite layer adhered to a low-profile side (such as a low-profile copper layer) of a conductive layer.

[0072] The following examples are provided to illustrate the present disclosure. These examples are illustrative only and are not intended to limit the devices manufactured in accordance with the present disclosure to the materials, conditions, or process parameters set forth therein.

[0073] Example

[0074] In the example, the minimum melt viscosity (MMV) is determined using parallel plate oscillatory rheology with a temperature ramp of 5 °C per minute. The viscosity and temperature when the film begins to soften to the minimum melt and before the crosslinker begins to increase the molecular weight are taken as the minimum melt viscosity and the corresponding temperature. The unit of the minimum melt viscosity is expressed in kilopascals (kP).

[0075] The dielectric constant (Dk) and dielectric loss (Df) (also known as the loss tangent) are measured at a temperature of 23 °C to 25 °C according to the test method of "Strip Line Test of Dielectric Constant and Loss Tangent at X-Band" (IPC-TM-650 2.5.5.5).

[0076] The glass transition temperature (Tg) and the coefficient of thermal expansion in the z-direction (CTE) are determined according to the "Glass Transition Temperature and Thermal Expansion of Materials Used in High Density Interconnection (HDI) and Microvias - TMA Method" (IPC-TM-650 2.4.24.5).

[0077] The copper roughness is determined using an atomic force microscope in contact mode and reported as Rz in micrometers calculated by determining the sum of the 5 highest measured peaks minus the sum of the 5 lowest valleys and then dividing by 5 (JIS (Japanese Industrial Standard) - B-0601); or the copper roughness is determined using white light scanning interferometry in non-contact mode, and the copper roughness is reported as Sa, Sq, Sz height parameters in micrometers (ISO 25178) using stitching techniques to characterize the processed side surface topography and texture.

[0078] The copper peel strength was determined according to the "Peel strength of metallic clad laminates" test method (IPC-TM-650 2.4.8). When testing the peel strength, each composite material layer was laminated with a stack of 1 / 2 ounce copper foils as shown in Table 1 on either side of the composite material layer at a pressure of 1.7 megapascals (MPa) at 185 °C using a typical epoxy curing cycle of 90 minutes. In the examples, the after-solder (AS) peel strength of the copper-clad laminates was tested. 1 / 2 ounce copper foil refers to the thickness of the copper layer achieved when 1 / 2 ounce (18.8 mm) of copper is flattened and evenly spread over an area of one square foot (929 square centimeters). The equivalent thickness is 0.01735 mm.

[0079] The components used in the examples are shown in Table 1.

[0080]

[0081] Examples 1 to 8: Effect of methacrylated fused silica

[0082] The composite material layer was prepared by first mixing the components as shown in Table 2. Then the reactive composition was cast as a horizontal film onto a silicone release liner. The resulting dielectric film layer had a thickness of 75 micrometers (3 mils). The minimum melt viscosity was determined, and the results are shown in Table 2 and Figure 1 where the open symbols are fused silica and the solid symbols are m-fused silica. Then twenty (20) composite material layers were laminated at a pressure of 1.7 megapascals (MPa) at 185 °C using a typical epoxy curing cycle of 90 minutes. The coefficient of thermal expansion values were determined, and the results are shown in Table 2 and Figure 1 The dielectric properties were determined at a thickness of 1,500 micrometers (60 mils) and are also shown in Table 2.

[0083]

[0084] Table 2 and Figure 1 show that replacing fused silica with methacrylated fused silica causes an unexpected decrease in both the minimum melt viscosity and the coefficient of thermal expansion in the z-direction while maintaining good copper peel strength.

[0085] Without being bound by theory, it is believed that treating fused silica with a functionalized silane serves to couple the inorganic silica with the organic isocyanurate-based thermoset. Evidence of this coupling is shown in Figure 2 and Figure 3 The dielectric properties were determined at a thickness of 1,500 micrometers (60 mils) and are also shown in Table 2. Figure 2Scanning electron microscope after polishing of a composition containing unprocessed fused silica. Figure 2 Clearly shows the presence of spherical voids on the surface, where fused silica particles are removed (unbonded) during the polishing step. In contrast, Figure 3 Scanning electron microscope after polishing of a composition containing methacrylated fused silica. Figure 3 Clearly shows that methacrylated fused silica particles are not removed during the polishing step and remain bonded to (present in) the composition.

[0086] Examples 9 to 11: Effect of methacrylated fused silica on peel strength

[0087] Composite material layers containing 33.0 vol% to 37.5 vol% of methacrylated fused silica of Examples 9 to 11 were prepared according to Examples 1 to 8 and are shown in Table 3. A plurality of properties were determined and the results are also shown in Tables 3 and 4.

[0088]

[0089] Table 3 shows that when increasing the volume loading of methacrylated fused silica and reducing the CTE on the z-axis, the layers of Examples 9 to 11 advantageously exhibit a high copper peel strength greater than 3 pli (0.54 kg / cm) for all tested copper foils.

[0090] The dielectric properties of Examples 9 to 11 were determined on laminates of different thicknesses including several layers of composite material layers. The results are shown in Table 4.

[0091]

[0092] Table 4 shows that laminates including the composite material layers of Examples 9 to 11 exhibit good dielectric constant values and low loss values at 10 GHz.

[0093] Examples 12 to 16: Effect of hydrocarbon resin diluent on composite material layers

[0094] Examples 12 to 16 as shown in Table 5 were prepared according to Examples 1 to 8, except that different diluents were added. The corresponding properties were determined and are also shown in Table 5.

[0095]

[0096] Table 5 shows that adding hydrocarbon resin diluent causes a significant reduction in the minimum melt viscosity while maintaining good CTE values and dielectric properties. It is thus concluded that adding hydrocarbon resin diluent represents a way to enhance resin filling and flow without adversely affecting the thermal reliability performance of plated through holes.

[0097] Examples 17 to 20 as shown in Table 6 were prepared according to Examples 1 to 8, except that different diluents were added. The corresponding properties were determined and are also shown in Table 6.

[0098]

[0099] Table 6 shows that the addition of a hydrocarbon resin diluent results in a significant reduction in the minimum melt viscosity, an improvement in the hole filling performance used as an index of the resin filling and flow ability, while maintaining good CTE values and dielectric properties.

[0100] The following describes non-limiting aspects of the present disclosure.

[0101] Aspect 1: A composition comprising: a hydrocarbon-based thermoplastic polymer containing repeating units derived from an α-olefin and a C 4-30 cycloolefin; a reactive monomer that can be free-radically crosslinked to produce a crosslinked network; a free-radical source; and a functionalized fused silica capable of chemically coupling with the crosslinked network.

[0102] Aspect 2: The composition of Aspect 1, wherein the hydrocarbon-based thermoplastic polymer comprises repeating units derived from at least one of the following: cyclobutene, cyclopentene, cycloheptene, cyclooctene, cyclodecene, norbornene, or an alkyl- or aryl-substituted norbornene (e.g., 5-methyl-2-norbornene, 5-hexyl-2-norbornene, 5-phenyl-2-norbornene, 5-ethyl-2-norbornene, 4,5-dimethyl-2-norbornene, exo-1,4,4a,9,9a,10-hexahydro-9,10(1',2')-bridged-phenylene-1,4-bridged-methanoanthracene, exo-dihydrodicyclopentadiene, or endo,exo-tetracyclododecene).

[0103] Aspect 3: The composition of any one or more of the foregoing aspects, wherein the hydrocarbon-based thermoplastic polymer has the formula (I).

[0104] Aspect 4: The composition of any one or more of the foregoing aspects, wherein the C 4-30 molar ratio of the cycloolefin repeating unit to the α-olefin repeating unit is from 6:1 to 0.5:1, or from 6:1 to 1.5:1.0.

[0105] Aspect 5: The composition of any one or more of the foregoing aspects, wherein the weight-average molecular weight of the hydrocarbon-based thermoplastic polymer is from 500 grams per mole to 105,000 grams per mole based on polystyrene standards.

[0106] Aspect 6: The composition of any one or more of the foregoing aspects, wherein based on the total volume of the composition, the composition comprises 10 volume percent to 90 volume percent, or 25 volume percent to 75 volume percent, or 30 volume percent to 50 volume percent of a hydrocarbon-based thermoplastic polymer. The hydrocarbon-based thermoplastic polymer may be non-reactive with other components of the composition.

[0107] Aspect 7: The composition of any one or more of the foregoing aspects, wherein the reactive monomer comprises triallyl (iso)cyanurate.

[0108] Aspect 8: The composition of any one or more of the foregoing aspects, wherein based on the total volume of the composition, the composition comprises 1 volume percent to 35 volume percent, or 5 volume percent to 25 volume percent, or 5 volume percent to 15 volume percent of a reactive monomer.

[0109] Aspect 9: The composition of any one or more of the foregoing aspects, wherein the free radical source comprises at least one of the following: peroxide, dimethyldiphenylhexane, methyl ethyl ketone peroxide, cyclohexanone peroxide, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 2,2-bis(tert-butylperoxy)butane, tert-butyl hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hex-3-yne, tert-butyl perbenzoate, α,α'-di-(tert-butylperoxy)diisopropylbenzene, or 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne, α,α'-bis(tert-butylperoxy-m-isopropyl)benzene, octanoyl peroxide, isobutyryl peroxide, peroxy dicarbonate / ester, α,α'-azobis(isobutyronitrile), redox initiator, acetyl azide, 2,3-dimethyl-2,3-diphenylbutane, 3,4-dimethyl-3,4-diphenylhexane, or 1,4-diisopropylbenzene; and / or wherein based on the total weight of the composition, the composition comprises 0.1 volume percent to 2 volume percent, or 0.5 volume percent to 1 volume percent of a free radical source.

[0110] Aspect 10: The composition of any one or more of the foregoing aspects, wherein the functionalized fused silica has a spherical morphology with an average diameter of 1 micron to 50 microns, or 1 micron to 10 microns.

[0111] Aspect 11: The composition of any one or more of the foregoing aspects, wherein based on the total volume of the composition, the composition comprises 10 volume percent to 70 volume percent, or 20 volume percent to 60 volume percent, or 40 volume percent to 55 volume percent of functionalized fused silica.

[0112] Aspect 12: The composition of any one or more of the foregoing aspects further comprises a hydrocarbon resin diluent having a weight average molecular weight of 200 grams per mole to 2,000 grams per mole based on polystyrene standards.

[0113] Aspect 13: The composition of any one or more of the foregoing aspects further comprises a hydrocarbon resin diluent; wherein the hydrocarbon resin diluent is derived from piperylene and optional aromatic repeat units; wherein the hydrocarbon resin diluent is optionally saturated.

[0114] Aspect 14: The composition of any one or more of the foregoing aspects, wherein based on the total volume of the composition, the composition comprises 0 volume percent to 50 volume percent, or 10 volume percent to 40 volume percent, or 5 volume percent to 30 volume percent of the hydrocarbon resin diluent.

[0115] Aspect 15: The composition of any one or more of the foregoing aspects, based on the total volume of the composition, further comprises 5 volume percent to 25 volume percent, or 8 volume percent to 20 volume percent of a flame retardant.

[0116] Aspect 16: A composite material layer derived from the composition of any one or more of the foregoing aspects.

[0117] Aspect 17: The composite material layer of aspect 16 having one or more of the following properties. The minimum melt viscosity of the composition can be greater than or equal to 80 kP, or be 80 kP to 700 kP. The peel strength of the composite material layer to copper can be greater than or equal to 0.54 kg / cm. The average coefficient of thermal expansion in the z-direction of the composite material layer at 150 °C to 250 °C can be less than or equal to 95 ppm / °C, or less than or equal to 90 ppm / °C. The dielectric constant of the composite material layer at 10 GHz can be 2.5 to 3.5. The dielectric loss of the composite material layer at 10 GHz can be less than or equal to 0.0030, or less than or equal to 0.0021, or be 0.001 to 0.0025.

[0118] Aspect 18: A method of manufacturing a composite material layer, such as a method of manufacturing the composite material layer of aspects 16 and 17, comprising: forming a layer from the composition of any one or more of aspects 1 to 15; and polymerizing reactive monomers in the composition to form a crosslinked network.

[0119] Aspect 19: The method of aspect 18, wherein the polymerization comprises at least one of raising the temperature of the layer, exposing the layer to ultraviolet irradiation, or exposing the layer to electron beam irradiation.

[0120] Aspect 20: The method of any one or more of aspects 18 to 19, wherein forming the layer comprises casting the composition on a release liner.

[0121] Aspect 21: The method of any one or more of aspects 18 to 19, wherein forming the layer comprises casting the composition onto a metal foil such as copper or aluminum.

[0122] Aspect 22: The method of any one or more of aspects 18 to 21, wherein forming the layer comprises impregnating a reinforcing layer with the composition. The impregnation can comprise at least one of casting the composition onto the reinforcing layer, dip-coating the reinforcing layer into the composition, or roll-coating the composition onto the reinforcing layer.

[0123] Aspect 23: A multi-layer article comprising the composite material layer of any one or more of aspects 16 to 22.

[0124] Aspect 24: The composition of any one or more of the foregoing aspects, wherein the functional group of the functionalized fused silica comprises at least one of (meth)acrylate group, vinyl group, allyl group, propargyl group, butenyl group, or styryl group.

[0125] Aspect 25: A composition of any one or more of the foregoing aspects, wherein the functionalized fused silica is derived from a functionalized silane comprising at least one of the following: (3-acryloxypropyl)trimethoxysilane, n-(3-acryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane, (3-acryloxypropyl)methyldimethoxysilane, methacryloxypropyltrimethoxysilane, o-(methacryloxyethyl)-n-(triethoxysilylpropyl)carbamate, n-(3-methacryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane, methacryloxymethyltriethoxysilane, methacryloxymethyltrimethoxysilane, methacryloxypropyltriethoxysilane, (methacryloxymethyl)methyldiethoxysilane, (methacryloxymethyl)methyldimethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylethoxysilane, methacryloxypropyldimethylmethoxysilane, vinyltriacetoxysilane, vinyltriethoxysilane, vinyltriisopropenyloxysilane, vinyltriisopropoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, vinyltris(methylethylketoxime)silane, (divinylmethylsilylethyl)triethoxysilane, docosenyltriethoxysilane, hexadecafluorododec-11-enyl-1-trimethoxysilane, hexenyltriethoxysilane, 7-octenyltrimethoxysilane, 0-undecenyltrimethoxysilane, o-(vinyloxybutyl)-n-(triethoxysilylpropyl)carbamate, vinyltri-tert-butoxysilane, vinyltris(methoxypropoxy)silane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, vinyldimethylethoxysilane, trivinylmethoxysilane, bis(triethoxysilylethyl)vinylmethylsilane, triethoxysilyl-modified poly-1,2-butadiene, diethoxymethylsilyl-modified poly-1,2-butadiene, 3-(n-allylamino)propyltrimethoxysilane, n-allyl-aza-2,2-dimethoxysilacyclopentane, allyltrimethoxysilane, allyloxyundecyltrimethoxysilane, allyltriethoxysilane, 2-(chloromethyl)allyltrimethoxysilane, o-(propargyloxy)-n-(triethoxysilylpropyl)carbamate, butenyltriethoxysilane, 3-(n-styrylmethyl-2-aminoethylamino)propyltrimethoxysilane, styrylethyltrimethoxysilane, (3-cyclopentadienylpropyl)trimethoxysilane, [2-(3-cyclohexenyl)ethyl]trimethoxysilane, or [2-(3-cyclohexenyl)ethyl]trimethoxysilane.The functionalized silane may include at least one of methacryloyl silanes, such as at least one of γ-methacryloyloxypropylmethyldimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylmethyldiethoxysilane, or γ-methacryloyloxypropyltriethoxysilane.

[0126] The compositions, methods, and articles may alternatively include, consist of, or consist essentially of any suitable materials, steps, or components disclosed herein. The compositions, methods, and articles may additionally or alternatively be formulated without or substantially free of any materials (or substances), steps, or components that are not necessary to achieve the functions or purposes of the compositions, methods, and articles.

[0127] The terms "a" and "an" do not denote a limitation of quantity, but rather denote the presence of at least one of the items recited. Unless the context clearly indicates otherwise, the term "or" means "and / or". References throughout the specification to "one aspect", "an aspect", "another aspect", "some aspects", etc. mean that a particular element (e.g., a feature, structure, step, or property) described in connection with that aspect is included in at least one aspect described herein, and may or may not be present in other aspects. Furthermore, it is to be understood that the described elements may be combined in any suitable manner in multiple aspects.

[0128] When an element (e.g., a layer, film, region, or substrate) is referred to as being "on" another element, it may be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements. It is to be understood that the present composite layer may be directly on one or more base layers.

[0129] Unless otherwise indicated herein, all test standards are the latest standards in effect as of the filing date of the present application (or, if priority is claimed, the filing date of the earliest priority application in which the test standard appears).

[0130] All ranges of endpoints of ranges involving the same components or properties, including the endpoints, may be combined independently and include all intermediate points and ranges. For example, a range of "up to 25 wt%, or 5 wt% to 20 wt%" includes the endpoints and all intermediate values of the range of "5 wt% to 25 wt%", such as 10 wt% to 23 wt%, etc.

[0131] All patents, patent applications, and other references cited are hereby incorporated by reference in their entirety. However, if a term in this application conflicts or contradicts a term in an incorporated reference, the term in this application shall control over the conflicting term of the incorporated reference.

[0132] Although particular aspects have been described, alternatives, modifications, variations, improvements, and substantial equivalents may be contemplated by the applicant or other persons skilled in the art, which are not presently foreseen or may not be presently foreseeable. Accordingly, the appended claims, which may be amended, are intended to cover all such alternatives, modifications, variations, improvements, and substantial equivalents.

Claims

1. A composition comprising: A hydrocarbon thermoplastic polymer containing repeating units derived from an α-olefin and a C cycloolefin, which is 30 to 50 volume percent of the total volume of the composition 4-30 ; 5 to 15 volume percent, based on the total volume of the composition, of a radically crosslinkable reactive monomer to produce a crosslinked network; A free radical source; 40 to 55 volume percent, based on the total volume of the composition, of a functionalized fused silica capable of chemically coupling with the crosslinked network; And 5 to 30 volume percent, based on the total volume of the composition, of a hydrocarbon resin diluent, wherein the weight average molecular weight of the hydrocarbon-based thermoplastic polymer is from 500 grams per mole to 105,000 grams per mole based on polystyrene standards, wherein the minimum melt viscosity of the composition is greater than or equal to 80 kPa·s.

2. The composition according to claim 1, wherein the hydrocarbon-based thermoplastic polymer comprises repeating units derived from at least one of the following: cyclobutene, cyclopentene, cycloheptene, cyclooctene, cyclodecene, norbornene, or alkyl- or aryl-substituted norbornene.

3. The composition according to claim 1, wherein the hydrocarbon-based thermoplastic polymer comprises repeating units derived from at least one of the following: 5-methyl-2-norbornene, 5-hexyl-2-norbornene, 5-phenyl-2-norbornene, 5-ethyl-2-norbornene, 4,5-dimethyl-2-norbornene, exo-1,4,4a,9,9a,10-hexahydro-9,10(1',2')-ethanoanthracene, exo-dihydrodicyclopentadiene, or endo,exo-tetracyclododecene.

4. The composition according to claim 1, wherein the hydrocarbon-based thermoplastic polymer has the formula (I), wherein R1, R2, and R3 are each independently H, C 1-30 alkyl, C 6-30 aryl; n is from 10 to 3,500; and m is from 1 to 5,300.

5. The composition according to claim 1, wherein the molar ratio of the C 4-30 cycloolefin repeating unit to the α-olefin repeating unit is from 6:1 to 0.5:

1.

6. The composition according to claim 1, wherein the molar ratio of the C 4-30 cycloolefin repeating unit to the α-olefin repeating unit is from 6:1 to 1.5:1.

0.

7. The composition according to claim 1, wherein the weight average molecular weight of the hydrocarbon-based thermoplastic polymer is from 70,000 grams per mole to 90,000 grams per mole based on polystyrene standards.

8. The composition according to claim 1, wherein the reactive monomer comprises triallyl (iso)cyanurate.

9. The composition according to claim 1, wherein the free radical source comprises at least one of the following: dicumyl peroxide, dimethyldiphenylhexane, methyl ethyl ketone peroxide, cyclohexanone peroxide, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 2,2-bis(tert-butylperoxy)butane, tert-butyl hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hex-3-yne, tert-butyl perbenzoate, α,α'-di-(tert-butylperoxy)diisopropylbenzene, or 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne, α,α'-bis(tert-butylperoxy-m-isopropyl)benzene, octanoyl peroxide, isobutyryl peroxide, peroxydicarbonates / esters, α,α'-azobis(isobutyronitrile), redox initiators, acetyl azide, 2,3-dimethyl-2,3-diphenylbutane, 3,4-dimethyl-3,4-diphenylhexane, or 1,4-diisopropylbenzene.

10. The composition according to claim 1, wherein the free radical source comprises at least one of the following: dicumyl peroxide, dimethyldiphenylhexane, methyl ethyl ketone peroxide, cyclohexanone peroxide, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 2,2-bis(tert-butylperoxy)butane, tert-butyl hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hex-3-yne, tert-butyl perbenzoate, α,α'-di-(tert-butylperoxy)diisopropylbenzene, or 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne, α,α'-bis(tert-butylperoxy-m-isopropyl)benzene, octanoyl peroxide, isobutyryl peroxide, peroxydicarbonates / esters, α,α'-azobis(isobutyronitrile), redox initiators, acetyl azide, 2,3-dimethyl-2,3-diphenylbutane, 3,4-dimethyl-3,4-diphenylhexane, or 1,4-diisopropylbenzene.

11. The composition according to claim 1, wherein the functionalized fused silica has a spherical morphology with an average diameter of 1 micrometer to 50 micrometers.

12. The composition according to claim 1, wherein the functionalized fused silica has a spherical morphology with an average diameter of 1 micrometer to 10 micrometers.

13. The composition according to claim 1, wherein based on polystyrene standards, the hydrocarbon resin diluent has a weight average molecular weight of 200 grams per mole to 2,000 grams per mole.

14. The composition according to claim 1, wherein the hydrocarbon resin diluent is derived from piperylene and optionally aromatic repeat units; wherein the hydrocarbon resin diluent is optionally saturated.

15. The composition according to claim 1, further comprising 5 volume percent to 25 volume percent of a flame retardant based on the total volume of the composition.

16. The composition according to claim 1, further comprising 8 volume percent to 20 volume percent of a flame retardant based on the total volume of the composition.

17. The composition according to claim 1, wherein the functional groups of the functionalized fused silica comprise at least one of (meth)acrylate groups, vinyl, allyl, propargyl, butenyl, or styryl.

18. A composite material layer derived from the composition according to any one of the preceding claims.

19. The composite material layer according to claim 18, wherein the composite material layer has at least one of the following: a peel strength to copper greater than or equal to 0.54 kilograms per centimeter; an average coefficient of thermal expansion in the z-direction at 150 degrees Celsius to 250 degrees Celsius less than or equal to 95 parts per million per degree Celsius; a dielectric constant at 10 gigahertz of 2.5 to 3.5; or a dielectric loss at 10 gigahertz less than or equal to 0.0030.

20. The composite material layer according to claim 19, wherein the minimum melt viscosity is 80 kilopoise to 700 kilopoise.

21. The composite layer according to claim 19, wherein the average coefficient of thermal expansion in the z-direction at 150 °C to 250 °C is less than or equal to 90 parts per million per degree Celsius.

22. The composite layer according to claim 19, wherein the dielectric loss at 10 GHz is less than or equal to 0.0021.

23. The composite layer according to claim 19, wherein the dielectric loss at 10 GHz is from 0.001 to 0.0025.

24. A method of manufacturing a composite layer according to any one of claims 19 to 23, comprising: forming a layer from the composition according to any one of claims 1 to 17; and polymerizing the reactive monomers in the composition to form a crosslinked network.

25. The method according to claim 24, wherein the polymerization comprises at least one of raising the temperature of the layer or exposing the layer to electron beam irradiation.

26. The method according to claim 24, wherein forming the layer comprises casting the composition onto a release liner.

27. The method according to claim 24, wherein forming the layer comprises casting the composition onto a metal foil.

28. The method according to claim 24, wherein forming the layer comprises casting the composition onto copper or aluminum.

29. The method according to claim 24, wherein forming the layer comprises impregnating a reinforcing layer with the composition.

30. A multilayer article comprising a composite layer according to any one of claims 19 to 23.

Images