SILPHENYLENE POLYMERS

Description

[0001] The present invention relates to radically curable silphenylene polymers, a process for their preparation and their use as binders in high-frequency applications. State of the art:

[0002] With the progressive development of high-frequency technology for wireless communications, the demand for materials suitable for its implementation is increasing. This affects all areas of materials, such as copper foils, binders, glass fibers, etc. Regarding binders, the epoxy resins traditionally used for the production of copper-clad laminates or, as a result, for circuit board production are no longer suitable due to their high dielectric loss factors. Polytetrafluoroethylene, which has a very low dielectric loss factor and is well-suited for high-frequency applications, has other disadvantages, particularly poor processability and poor adhesion properties, which make an alternative desirable.Polyphenylene ethers are currently being used extensively as binders for this application because they combine low dielectric loss factors with good mechanical and thermal properties and water repellency. Other organic polymers are also being considered in current development activities for this application, such as bismaleimide polymers, bismaleimide triazine copolymers, and hydrocarbon resins, although this list could be expanded to include others.

[0003] Polyorganosiloxanes generally possess excellent heat resistance, weathering stability and hydrophobicity, are flame-resistant and have low dielectric loss factors.

[0004] These property profiles qualify both the aforementioned organic polymers and the polyorganosiloxanes for use as binders in the production of high-frequency-capable copper-clad laminates and components, such as circuit boards and antennas. Therefore, it makes sense to utilize the positive properties of these material classes for modern high-frequency applications, whereby they can be used both individually and in combination with each other to symbiotically enhance their performance. Corresponding experiments have already been documented in the state of the art.

[0005] Polar substituents are undesirable because they increase the dielectric loss factor. In this context, polyorganosiloxanes have an inherent disadvantage compared to other organic binders, as their framework is composed of silicon atoms and oxygen atoms, which usually alternate. The difference in electronegativity between silicon and oxygen according to the Allred and Rochow electronegativity scale is 3.50 - 1.74 = 1.76. The electronegativity value for silicon is 1.74, and 3.5 is the electronegativity value for oxygen. In contrast, the electronegativity difference between carbon and oxygen is only 3.5 - 2.5 = 1.0, where 2.5 is the electronegativity value for carbon.It is now known that differences in electronegativity can be sterically shielded and not be externally apparent, as is the case with polytetrafluoroethylene, which exhibits excellent dielectric properties despite an electronegativity difference between carbon and fluorine of 1.67. A similar shielding effect could be assumed for symmetrical polydiorganosiloxanes, such as polydimethylsiloxanes. However, unlike polytetrafluoroethylene, polydimethylsiloxanes do not possess suitable processing properties for use as binders for high-frequency applications. For example, the production of prepregs and their subsequent curing is not possible with polydiorganosiloxanes, and sufficiently high viscosities cannot be achieved to prevent the polydiorganosiloxanes from flowing away under the influence of the heat of molten tin during a soldering process.Even through crosslinking, such as the radical polymerization of the binders used, which is preferred for the production of metal-clad laminates, polydiorganosiloxanes cannot achieve sufficient mechanical strength under heat stress. Instead of highly crosslinked bodies that retain their shape even under thermal stress, as required for this application, polyorganosiloxanes, after crosslinking under the influence of heat, produce polymers that are reversibly deformable, i.e., elastomeric, if necessary. Furthermore, polydiorganosiloxanes are incompatible with organic polymers, so the possibilities for formulating suitable binder mixtures are significantly limited, if not completely eliminated.

[0006] Polyorganosiloxanes, which have a three-dimensional framework structure and are also chemically crosslinkable to form thermosets, are suitable binders for high-frequency applications. Corresponding examples are known in the patent literature, see, for example, US 2016 / 0244610 (compositions of mixtures of olefinically unsaturated MQ resins with unsaturated modified polyphenylene ethers), US 2018 / 0220530 (compositions of mixtures of polyphenylene ethers with MT, MDT, MDQ, and MTQ silicone resins), or US 2018 / 0215971 (compositions of mixtures of polyphenylene ethers with TT and TQ silicone resins).

[0007] In these inventions, dielectric loss factors of < 0.007 are aimed for. This requirement is met with freshly produced test specimens made from the materials described therein, although not significantly undercut. Thus, these state-of-the-art materials leave considerable room for improvement, as they are significantly far removed from the dielectric properties of polytetrafluoroethylenes, which achieve dielectric loss factors in the range of 0.0001. Since complete shielding of the polarities of the Si-O-Si framework units is not possible in polyorganosiloxanes with a three-dimensional framework structure, this structural element becomes an inherent disadvantage for polyorganosiloxanes and will always prevent them from achieving lower dielectric loss factors.

[0008] Attempts to replace parts of the polyorganosiloxane framework with bridging units other than Si-O-Si units are documented, for example, in US 3395168. What these inventions have in common, however, is that significant portions of the polyorganosiloxane framework are nevertheless retained.

[0009] US 6072016 teaches linear condensation-curing silphenylene polymers as part of a condensation-curing silicone preparation. The linear condensation-curing silphenylene polymers described therein are themselves condensable by hydrolyzable end groups. In principle, these linear condensation-curing silphenylene polymers can be free of Si-O-Si units; however, as intended, curing results in polyorganosiloxanes in which, in some cases, other linkages between neighboring silicon atoms are present instead of Si-O-Si units, with the units bridging the Si atoms being Si-C bonded. In addition to silphenylene units, the silphenylene polymers also contain silalkylene units, which is an unavoidable side effect of their production by hydrosilylation reactions of olefinically unsaturated silphenylene units. Pure polysilphenylenes are not accessible in this way and are not taught in US 6072016.It should also be noted that the starting materials used for hydrosilylation in US 6072016 are only accessible through metal-mediated coupling reactions, such as the Grignard reaction or a Wurtz coupling. Although these are feasible on an industrial scale, they are challenging synthesis processes. The overall effort required to implement this technology is so significant that it must be assumed that this technology will not be successful due to a lack of economic viability, or will only be successful in extremely high-priced and correspondingly very small-volume markets. Regarding the dielectric properties, it is to be expected that increased dielectric loss factors are to be expected due to platinum residues in the hydrosilylation product, so that a further step would be necessary to make the already complex technology usable for high-frequency applications.The prior art according to US 6072016 would first have to be further developed in order to be technically usable in the target application of the present invention, apart from the additional economic disadvantages that arise therefrom.

[0010] US 10982053 describes polymers comprising linear aliphatic polyethers modified with silphenylene units. The polymers described therein can carry phenol or epoxy groups. The copolymers described therein are obtained by hydrosilylation of olefinically unsaturated polyethers with Si-H-functional silphenylene units. According to the teaching of US 10982053, pure silphenylene polymers are not available. The essential structural unit of the polymers according to US 10982053 is the polyether unit.

[0011] US 2011 / 0275768 represents a similar teaching to US 10982053, whereby the organic units located between the individual silphenylene units differ from the polyether units according to US 10982053. Also in the case of US 2011 / 0275768, organosilicon polymers consisting exclusively or predominantly of silphenylene units are not covered by the subject matter of the teaching described therein.

[0012] EP 0913420 teaches alternating silphenylene silalene polymers obtained by hydrosilylation reactions of olefinically unsaturated silphenylene units with Si-H-terminal silphenylene units, similar to US 6072016. Regarding economic viability, the same statements apply here as already presented for US 6072016. Here, too, complex metal-mediated coupling reactions are required to produce the required starting materials. Hydrosilylation can only take place subsequently, which itself is an expensive synthesis due to the platinum catalyst used. The platinum remains in the product and increases the dielectric loss factor. Platinum would first have to be separated to achieve high-frequency dielectric properties. This requires a further step and an improvement on the prior art according to EP 0913420, which goes beyond the teaching of EP 0913420.

[0013] In the copolymers according to EP 0913420, as the designation "silphenylenesilalkylene polymers" already suggests, phenylene and alkylene bridging units regularly alternate. This is unavoidable because the vinyl groups required for polymer synthesis, which hydrosilylate with Si-H units, become alkanediyl units bridging the Si atoms, which regularly alternate with the phenylene units in the finished polymer backbone. The phenylene units bridging the Si atoms, as described above, are only obtainable through metal-mediated coupling reactions, be it the Grignard reaction or a Wurtz-type coupling. Therefore, in the silphenylenesilalkylene copolymers according to EP 0913420, 50% of the bridging residues bridging adjacent Si atoms are arylene residues and 50% are alkylene residues or alkanediyl residues.Since only symmetrically doubly functionalized starting building blocks are used, high-molecular-weight linear polymers are obtained that are terminated by the remaining Si-H or olefinic groups. Instead of doubly olefinically unsaturated silphenylene building blocks, doubly hydrosilylatable, purely organic starting building blocks, such as diolefins or acetylenes, can also be used. The silphenylenesilalkylene polymers described therein are only sufficiently soluble to be used as coating materials in the target application if a minimum proportion of 20 mol% of silicon-bonded phenyl substituents is present. Statistically structured silphenylene polymers are neither described in EP 0913420 nor are they accessible by the processes described in EP 0913420. The range of structural chemistry accessible according to this prior art is therefore very limited.EP 0913420 therefore does not teach a general approach to any silphenylene polymer. The use of aliphatic units in the silphenylene-silalkylene copolymers according to EP 0913420 is unavoidable. It is known that lower thermal stabilities are achieved with aliphatic silicon-bonded units than with aromatic silicon-bonded radicals. If the silalkylene units in the silphenylene-silalkylene copolymers according to EP 0913420 are replaced with siloxane units, high thermal stabilities can be achieved, as partially described in the previously cited prior art. However, since this results in disadvantages with regard to the achievable dielectric properties, the known prior art always achieves either reduced thermal stability or reduced performance with regard to the dielectric properties.The combination of high thermal resistance, as expected from pure silphenyl polymers, and the best possible electrical insulating properties, obtainable in an economical process, cannot yet be derived from the existing state of the art. The present invention addresses this problem.

[0014] US 9751989 teaches condensation-curable polyorganosiloxanes with oligosilphenylene units for use as encapsulation material for LEDs. US 2017 / 051114 teaches hydrosilylation-curing preparations containing Si-H-terminated oligosilphenylenes and alkenyl-functional polyorganosiloxanes. In both cases, when used as intended, the end product obtained is polyorganosiloxanes containing both polyorganosiloxane units and oligosilphenylene units. Olefinically unsaturated, radically curable silphenylene polymers are not part of the teaching of these two documents.

[0015] Document EP 3 133 106 B1 discloses silphenylenealkylene polymers with vinyl groups. Task and subject matter of the invention:

[0016] The task was to provide polymers crosslinkable by radical polymerization that combine the advantageous properties of three-dimensionally crosslinkable polyorganosiloxanes such as excellent heat resistance, weathering stability, hydrophobicity and flame resistance with improved dielectric properties, in particular lower dielectric loss factors, which are suitable for use as binders for metal-clad laminates for electronic applications and are economically accessible.

[0017] This includes having a dielectric loss factor of no more than 0.0030 as a pure binder at 10 GHz, readily wetting any fillers that may be present that reduce the dielectric loss factor, allowing the production of tack-free prepregs, producing formulations compatible with organic polymers, curing under the influence of heat to form dimensionally stable molded bodies, and being readily soluble in the solvents typically used in the application. This problem is solved by the invention.

[0018] The invention relates to silphenylene polymers of the formula (I) R a R 1< 4 Si[Y[(SiR 2< c R 3< d ) e ] f ] g YSiR a R 1< b (I), where R can be identical or different radicals and represent a hydrogen radical or an olefinically or acetylenically unsaturated aliphatic or cycloaliphatic hydrocarbon radical, R 2< independently of one another represent identical or different radicals, where R 2< can represent a hydrogen radical or a saturated or olefinically or acetylenically unsaturated Si-C bonded C 1 - C 18 hydrocarbon radical, which can be substituted by heteroatoms, with oxygen atoms and silicon atoms being preferred as heteroatoms, with the plurality of oxygen atoms in the same radical R 2< always being separated from one another by hydrocarbon units and oxygen atoms and silicon atoms not being bonded to one another to form Si-O units if both types of heteroatoms are present simultaneously in a radical R 2<, but rather these are always separated from one another by hydrocarbon units,whereas several Si atoms in the same radical R 2< may optionally be connected to one another by direct Si-Si bonds and the Si atoms are always tetravalent and the remaining valences of the Si atoms are saturated by further Si-C-bonded substituents, preferably C 1 - C 12 alkyl, cycloalkyl or aryl radicals, where these may be olefinically or acetylenically unsaturated, and R 2< may also comprise olefinically or acetylenically unsaturated functional groups which may also contain heteroatoms, where R 2< may also be a hydroxy radical or a monovalent aliphatic, cycloaliphatic or aromatic Si-C-bonded, unsubstituted or heteroatom-substituted organic hydrocarbon radical having 1 to 18 C atoms and bonded to the silicon atom by an oxygen atom.

[0019] The radical R 2< can in particular also be a radical of the formula (II) [Y[(SiR 2< c R 3< d ) e ] f ] g YSiR a R 1< b, where Y, R, R 1< , R 2< , R 3< , a, b, c, d, e, f and g have the meanings given in the text.

[0020] R 1< and R 3< can independently of one another be identical or different radicals and can be either a hydrogen radical or a monovalent aliphatic, cycloaliphatic or aromatic Si-C bonded, unsubstituted or substituted by heteroatoms organic hydrocarbon radical having 1 to 18 C atoms, which can also be an unsaturated hydrocarbon radical, where R 1< and R 3< can also be a hydroxy radical or a monovalent aliphatic, cycloaliphatic or aromatic Si-C bonded, unsubstituted or substituted by heteroatoms organic hydrocarbon radical having 1 to 18 C atoms and bonded to the silicon atom by an oxygen atom.

[0021] It is a condition according to the invention that at least one olefinically or acetylenically unsaturated radical R, R 1< , R 2< or R 3< must always be present per silphenylene polymer of the formula (I). Preferably, at least two such olefinically or acetylenically unsaturated radicals R, R 1< , R 2< or R 3< are present per silphenylene polymer of the formula (I). The olefinically or acetylenically unsaturated radicals R and R 1< are always terminally bonded, while the olefinically or acetylenically unsaturated radicals R 2< and R 3< are always bonded to Si atoms located inside the polymer backbone (= internal). There is no particular restriction as to whether the olefinically or acetylenically unsaturated groups are terminal or internal. Both are possible, optionally also as a mixed form.However, it is a condition according to the invention that the preferably at least 2 olefinically or acetylenically unsaturated groups are present on different Si atoms and are not bonded to the same Si atom.

[0022] With regard to the number of oxygen-bonded radicals R, R 1< , R 2< and R 3<, it should be noted that the sum of all organic radicals bonded to Si atoms by an oxygen atom, based on the sum of all Si-bonded radicals R, R 1< , R 2< and R 3< as 100 mol%, may be at most 10 mol%, particularly preferably at most 8 mol%, in particular at most 5 mol%, very particularly preferably less than 1 mol%. It should be noted that radicals bonded to Si atoms by oxygen atoms are not desired in the silphenylene polymers of the formula (I) according to the invention. They do not contribute to improved performance of the silphenylene polymers according to the invention, but on the contrary result in reduced performance. It is therefore most preferred that no radicals bonded to Si atoms by oxygen atoms are present in the silphenylene polymers according to the invention.However, their formation cannot always be completely suppressed due to side reactions during synthesis. Therefore, limited amounts are permitted according to the invention, although not preferred. The best performance is achieved by completely avoiding any Si-O bonds in the silphenylene polymers according to the invention.

[0023] The silphenylene polymers according to the invention preferably contain less than 10 mol% of Si-O-linked units, more preferably less than 8 mol% of Si-O-linked units, in particular less than 5% of Si-O-linked units, most preferably less than 1% of Si-O-linked units. Si-O-linked units are understood to mean both Si-O-Si framework units and Si-O units in which the oxygen atom is bonded to a silicon atom on only one side and the second oxygen-bonded radical is not bonded to the oxygen by a silicon atom. In particular, it is preferred that the silphenylene polymers according to the invention be free of Si-O-Si units. The silphenylene polymers according to the invention can be blended with polyorganosiloxanes and / or polysiloxane-polysilphenylene copolymers and / or organic polymers and, if appropriate, used together with these, provided this is advantageous for the chosen application.Such mixtures, as well as those containing organic polymers, additives, fillers, pigments, etc. in addition to the silphenylene polymers according to the invention, are also according to the invention.

[0024] Y denotes a chemical bond or a di- to twelve-valent aromatic, alkylaromatic, cycloalkylaromatic or a di- to twelve-valent aliphatic or cycloaliphatic radical having 1 to 48 C atoms, the main chain of which is free of heteroatoms, so that the main chain does not, for example, have an ether or polyether structure, but these can optionally only be present as a pendant radical bound to the main chain, where Y can also contain olefinically or acetylenically unsaturated functional groups which, in addition to carbon atoms, can also comprise heteroatoms such as N, P, O and S atoms, with oxygen atoms being particularly preferred as heteroatoms in the functional groups, with it being excluded that several oxygen atoms are bonded directly to one another.

[0025] The radical Y, unless it represents a chemical bond, is always bonded to the silicon atoms bridged by it by a Si-C bond. Y preferably represents a divalent to dodecavalent aromatic, alkylaromatic, or cycloalkylaromatic radical. It is a condition of the invention that there is always a greater number of such divalent to dodecavalent aromatic, alkylaromatic, and cycloalkylaromatic radicals than divalent to dodecavalent aliphatic or cycloaliphatic radicals, and that the divalent to dodecavalent aliphatic or cycloaliphatic radicals alternate with the divalent to dodecavalent aromatic, alkylaromatic, or cycloalkylaromatic radicals statistically and not in a regular sequence.This also means that the di- to twelve-valent aromatic, alkylaromatic, cycloalkylaromatic radicals and the di- to twelve-valent aliphatic or cycloaliphatic radicals can be present in blocks, each consisting of a larger number of di- to twelve-valent aromatic, alkylaromatic, cycloalkylaromatic radicals or di- to twelve-valent aliphatic or cycloaliphatic radicals.

[0026] A further requirement for the silphenylene polymers according to the invention is that there is always a greater number of Y radicals that represent a divalent to twelve-valent aromatic, alkylaromatic, or cycloalkylaromatic radical than Y radicals that represent a chemical bond. Based on all bridging Y radicals as 100 mol%, at least 55 mol% are Y radicals that represent a divalent to twelve-valent aromatic, alkylaromatic, or cycloalkylaromatic radical, preferably at least 60 mol%, particularly preferably at least 70 mol%, and in particular at least 80 mol%. In a particularly preferred form of the invention, all Y radicals are those that represent a divalent to twelve-valent aromatic, alkylaromatic, or cycloalkylaromatic radical.

[0027] The silphenylene polymers of the invention have a random composition, i.e., a random composition. The condition of random composition is readily achieved by the synthesis process, which does not favor the formation of silphenylene polymers with Y radicals containing regularly alternating aromatic units and aliphatic or cycloaliphatic Y radicals.

[0028] Several Y radicals can have their meaning independently of one another, so that several Y radicals can be different radicals within the scope of the meanings given in a silphenylene polymer of the formula (I).

[0029] The indices have the following meaning: a denotes a number with a value of 1 or 2, preferably 1. b denotes a number with a value of 1 or 2, preferably 2, where the sum a + b = 3. c denotes a number with a value of 0, 1 or 2. d denotes a number with a value of 0, 1 or 2, where the sum c + d = 2. e denotes a number from 1 to 12, preferably from 1 to 6, particularly preferably 1 to 3, in particular 1. If e in [(SiR 2< c R 3< d ) e ] denotes a number greater than 1, then a plurality of units of the formula (SiR 2< c R 3< d ) are bonded to one another via Si-Si bonds, so that disilane, trisilane, etc. up to polysilane units are obtained, depending on the value of e. f means a number with a value of 1 to 12, in particular 1. g means a number with a value of 3 to 250, particularly preferably from 4 to 150, in particular from 5 to 50.

[0030] Examples of R radicals other than the hydrogen atom are alkenyl radicals, such as 7-octenyl, 5-hexenyl, 3-butenyl, allyl, and vinyl. Also included are acryloyloxy and methacryloyloxy radicals of acrylic acid or methacrylic acid, as well as the acrylic acid esters or methacrylic acid esters of unbranched or branched alcohols with 1 to 15 carbon atoms. Preferred such radicals are those derived from methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, t-butyl acrylate, t-butyl methacrylate, 2-ethylhexyl acrylate, and norbornyl acrylate. Particularly preferred are methyl acrylate, methyl methacrylate, n-butyl acrylate, iso-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, and norbornyl acrylate.These radicals are preferably not bonded directly to the silicon atom, but are bonded via a hydrocarbon spacer which may comprise 1 to 12 carbon atoms, preferably comprising 1 or 3 carbon atoms and not comprising any further heteroatoms apart from the heteroatoms contained in the acryloyloxy or methacryloyloxy radical.

[0031] Examples of radicals R 1< , R 2< and R 3< other than the hydrogen atom are saturated or unsaturated hydrocarbon radicals which may contain aromatic or aliphatic double bonds, for example alkyl radicals such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, isopentyl, neo-pentyl and tert.- Pentyl radical, hexyl radicals such as the n-hexyl radical, heptyl radicals such as the n-heptyl radical, octyl radicals such as the n-octyl radical and iso-octyl radicals such as the 2, 2, 4-trimethylpentyl and the 2-ethylhexyl radical, nonyl radicals such as the n-nonyl radical, decyl radicals such as the n-decyl radical, dodecyl radicals such as the n-dodecyl radical, tetradecyl radicals such as the n-tetradecyl radical, hexadecyl radicals such as the n-hexadecyl radical and octadecyl radicals such as the n-octadecyl radical, cycloalkyl radicals such as the cyclopentyl, cyclohexyl and 4-ethylcyclohexyl radical, cycloheptyl radicals, norbornyl radicals and methylcyclohexyl radicals, aryl radicals such as the Phenyl, biphenyl, naphthyl, anthryl, and phenanthryl radicals; alkaryl radicals such as o-, m-, and p-tolyl radicals, xylyl radicals, and ethylphenyl radicals; aralkyl radicals such as the benzyl radical; alkenyl radicals such as the 7-octenyl, 5-hexenyl, 3-butenyl, allyl, and vinyl radicals, as well as the alpha- and ß-phenylethyl radicals.

[0032] Preferred heteroatoms that may be contained in the radicals R 1< , R 2< and R 3< are oxygen atoms.

[0033] In addition, nitrogen atoms, phosphorus atoms, sulfur atoms and halogen atoms such as chlorine atoms and fluorine atoms are also possible, but not preferred.

[0034] Examples of preferred organic radicals R 1<, R 2<, and R 3< containing heteroatoms are the acryloyloxy and methacryloyloxy radicals of acrylic acid or methacrylic acid, as well as the acrylic acid esters or methacrylic acid esters of unbranched or branched alcohols containing 1 to 15 carbon atoms. Preferred such radicals are those derived from methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, 2-ethylhexyl acrylate, and norbornyl acrylate. Particularly preferred are methyl acrylate, methyl methacrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, 2-ethylhexyl acrylate, and norbornyl acrylate.These radicals are preferably not directly bonded to the silicon atom, but are bonded via a hydrocarbon spacer, which may comprise 1 to 12 carbon atoms, preferably comprising 1 or 3 carbon atoms and containing no further heteroatoms apart from the heteroatoms contained in the acryloyloxy or methacryloyloxy radical. The radicals R 1< , R 2< , and R 3< are preferably selected from methyl, phenyl, vinyl, acryloyloxy, and methacryloyloxy radicals, as well as the acrylic acid esters or methacrylic acid esters of unbranched or branched alcohols having 1 to 15 carbon atoms.

[0035] Further preferred radicals R 1< , R 2< and R 3< comprising heteroatoms are those of the formula (III).

[0036] In formula (III), R 4< , R 5< , R 6< , R 7< , R 8< and R 9< independently of one another represent a hydrogen radical, a hydrocarbon group or a hydrocarbon group substituted by foreign atoms, where at least one of the radicals R 4< , R 5< , R 6< , R 7< , R 8< and R 9< is always a hydrocarbon group which is bonded to the silicon atom via a Si-C bond, wherein it is preferred that this hydrocarbon group, via which the radical of formula (III) is bonded to a silicon atom, is a C3 hydrocarbon group which contains no heteroatoms. Alternatively, the radicals R 4< , R 5< , R 6< , R 7< , R 8< and R 9< can also be a chemical bond, so that the radical of formula (III) is directly bonded to the silicon atom via a Si-C bond to the aromatic ring.

[0037] Examples of radicals R 4< , R 5< , R 6< , R 7< , R 8< and R 9< are the hydrogen radical, saturated hydrocarbon radicals such as methyl, ethyl, n-propyl, iso-propyl, the primary, secondary and tertiary butyl radical, the hydroxyethyl radical, aromatic radicals such as the phenylethyl radical, the phenyl radical, the benzyl radical, the methylphenyl radical, the dimethylphenyl radical, the ethylphenyl radical, heteroatom-containing radicals such as the hydroxymethyl radical, the carboxyethyl radical, the methoxycarbonylethyl radical and the cyanoethyl radical and acrylate and methacrylate radicals such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, iso-butyl acrylate, iso-butyl methacrylate, t-butyl acrylate, t-Butyl methacrylate, 2-ethylhexyl acrylate and norbornyl acrylate, olefinically or acetylenically unsaturated hydrocarbon residues.Optionally, the adjacent radicals R 4< and R 6< as well as the adjacent radicals R 5< and R 7< can also be linked to one another to form the same cyclic saturated or unsaturated radical, so that fused polycyclic structures are formed.

[0038] Examples of phenol radicals of the formula (III) are the phenol radical, the ortho-, meta- or para-cresol radical, 2,6-, 2,5-, 2,4- or 3,5-dimethylphenol radical, 2-methyl-6-phenylphenol radical, 2,6-diphenylphenol radical, 2,6-diethylphenol radical, 2-methyl-6-ethylphenol radical, 2,3, 5-, 2,3,6- or 2,4,6-trimethylphenol radical, 3-methyl-6-tertiary-butylphenol radical, thymol radical and 2-methyl-6-allylphenol radical, which may optionally be substituted on the oxygen atom.

[0039] Preferred examples of fluorine-containing radicals are the trifluoropropyl, nonafluorohexyl and heptadecafluorooctyl radicals.

[0040] Y is preferably a bridging organic, preferably aromatic, unit having 1 to 24 carbon atoms between two to twelve carbosilyl units. Y is preferably divalent, trivalent, or tetravalent, especially divalent.

[0041] Preferred bridging aromatic radicals Y are those of the formula (IVa), (IVb) and (IVc) where the radicals R 10< , R 11< , R 12< and R 13< may be hydrogen or an optionally substituted hydrocarbon radical or a group of the formula OR 14< where R 14< is a hydrocarbon radical. Adjacent radicals such as, for example, R 10< and R 12< or R 11< and R 13< in formula (IVa) may be coupled to one another to form cyclic radicals, thus forming fused ring systems. The same applies to the adjacent radicals in formulae (IVb) and (IVc).

[0042] Typical examples of such bridging aromatic radicals are the p-, m- or o-phenylene radical, the 2-methyl-1,4-phenylene radical, the 2-methoxy-1,4-phenylene radical, with the p-phenylene radical being particularly preferred.

[0043] If appropriate, several such radicals can also be coupled together, so that, for example, two or more units of the formulas (IVa), (IVb), and (IVc) are coupled together, and this oligomeric bridging structural element is present by bonding the corresponding carbon atoms of the terminal aromatic rings to silicon atoms. Mixed forms are also conceivable, i.e., oligomeric bridging units that consist not only of units of one type of formulas (IVa), (IVb), or (IVc), but of several, i.e., two or three different types of repeating units that obey the formulas (IVa), (IVb), and (IVc). The aromatic units can be directly bonded to one another or they can be coupled together by a bridging group such as an alkanediyl unit, for example, the methylene group, the 1,2-ethanediyl group, 1,1-ethanediyl group, the 2,2-dimethylpropyl group, or a sulfone group.

[0044] Further examples of aromatic bridging units, which may also contain heteroatoms, are those in which two optionally substituted phenol rings are bridged via an alkanediyl or other unit. Typical representatives are 2,2-bis(4-hydroxyphenyl)propane radicals substituted on the phenol oxygen (substituted bisphenol A radicals), 2,2-bis(4-hydroxyphenyl)methane radicals (substituted bisphenol F radicals), and bis(4-hydroxyphenyl)sulfone radicals (bisphenol S radicals), where the phenol oxygen atoms are typically substituted with radicals of the type -(C 3 H 6 )-, where the -(C 3 H 6 )- radicals are bonded to silicon atoms Si-C, thereby creating the bridge.

[0045] Preferred Y radicals not bridged by an aromatic unit are, in addition to the chemical bond, alkanediyl, alkenediyl and alkynediyl radicals, which may optionally contain heteroatoms and which may contain aromatic groups as substituents, but which do not take over or contribute to the bridging function in these radicals.

[0046] Typical examples are the methylene radical, the methine radical, the tetravalent carbon, the 1,1-ethanediyl and the 1,2-ethanediyl group, the 1,4-butanediyl and the 1,3-butanediyl group, the 1,5-pentanediyl, 1,6-hexanediyl, 1,7-heptanediyl, 1,8-octanediyl, 1,9-nonadiyl, 1,10-decanediyl, 1,11-undecanediyl and the 1,12-dodecanediyl group, the 1,2-diphenylethanediyl group, the 1,2-phenylethanediyl group, the 1,2-cyclohexylethanediyl group. If a linear bridging unit has more than one carbon atom and the substitution pattern allows it, each of these groups can act as a bridge not only through alpha-omega connectivity, i.e. bridging through the first and last atom of a linear unit, but also through any other connectivity, i.e. the use of other chain carbon atoms.In addition, typical examples are not only the linear representatives of the bridging hydrocarbons mentioned, but also their isomers, which in turn can have a bridging effect by binding different C atoms of the hydrocarbon structure to silicon atoms.

[0047] Examples of particularly preferred radicals from the group of non-aromatic heteroatom-free hydrocarbon radicals are -CH 2 CH 2 -, -CH(CH 3 )-, -CH=CH-, -C(=CH 2 )- and -C≡C-.

[0048] Examples of typical fluorine-substituted bridging radicals Y are the -C(CF 3 ) 2 -, the -C(H)FC(H)F- and the -C(F 2 )-C(F 2 )- radical.

[0049] Examples of typical heteroatom-containing, non-aromatic bridging radicals include divalent hydrocarbon radicals that contain secondary or tertiary alcohol functions, keto, carboxylic acid, and ester functions, or have pendant ether chains. "Pendant" means that the respective radical originates from a C atom of the radical Y, but the end of the radical is not bonded to a silicon atom that is bonded to other silicon atoms via a bridging radical. Therefore, this radical does not contribute to a network structure.

[0050] All lists are only examples and should not be understood as limiting.

[0051] As explained later, the preferred method for preparing the silphenylene polymers of the invention involves a Grignard reaction-type synthesis. Groups listed here as examples that are not inert to magnesium would not be tolerated in such a reaction and would be converted accordingly. To nevertheless obtain them in the silphenylene polymers of the invention, only groups that are inert to magnesium are initially used in the Grignard reaction, which are then converted into the precursors obtained from the Grignard reactions in subsequent reactions according to known prior art. Such groups include, for example, groups containing carbonyl groups, such as acryloyl or methacryloyloxy groups.

[0052] The silphenylene polymers according to the invention can vary in viscosity over a wide range depending on the average number of structural units per molecule forming them or can also be solids.

[0053] Liquid silphenylene polymers according to the invention have viscosities of 20 to 8,000,000 mPas, preferably 200 to 5,000,000 mPas, in particular 250 to 3,000,000 mPas, in the uncrosslinked state at 25°C.

[0054] Solid silphenylene polymers according to the invention have, in the uncrosslinked state, glass transition temperatures in the range from 25°C to 250°C, preferably from 30°C to 230°C, in particular from 30°C to 200°C.

[0055] The silphenylene polymers of the invention can, in principle, be obtained by any process that leads to bond formation between Si atoms and carbon atoms. Typical examples of such reactions are Grignard reactions, coupling reactions according to the Wurtz synthesis, optionally with adjustments in the synthesis process, and hydrosilylation reactions. All of these reaction types are generally state of the art and therefore known to the person skilled in the art. For a basic overview of these and other organometallic reactions for Si-C bond formation, please refer to the Silicon Chemistry module at the University of Freiburg, accessible via the link: https: / / tufreiberg.de / sites / default / files / media / institut-fueranorganische-chemie-10441 / lehre / kroke / siliciumchemie5.pdf Notes and information on the procedure for Grignard syntheses can be found, for example, in Synthesis of Silphenylene-Containing Siloxane Resins Exhibiting Strong Hydrophobicity and High Water Vapor Barriers, Xunjun Chen, Minghao Yi, Shufang Wu, Lewen Tan, Yixin Xu, Zhixing Guan, Jianfang Ge and Guoqiang Yin, Coatings 2019, 9, 481.

[0056] To produce the silphenylene polymers according to the invention, attention must be paid to the appropriate selection of the reaction conditions and the raw materials.

[0057] As already indicated in the discussion of the prior art, the hydrosilylation reaction is not preferred for preparing the silphenylene polymers according to the invention. EP 0913420 explains which raw materials are required to carry out the hydrosilylation reaction to obtain the silphenylene-silalkylene polymers described in EP 0913420. These are disilphenylenes and olefinically unsaturated silphenylenes or diunsaturated silanes. The corresponding silphenylene starting materials are in turn accessible via Grignard reactions. This would be no different in the case of the present silphenylene polymers according to the invention. This means that compared to a Grignard or Wurtz synthesis or possibly another procedure that directly yields the silphenylene polymers according to the invention, hydrosilylation represents a disadvantage due to additional steps, increased complexity, and thus reduced economic efficiency.Since the present invention does not involve regularly alternating structural elements in the polymer backbone, as is the case in EP 0913420, but rather randomly composed polymers, a larger number of suitable raw materials would be required for a successful hydrosilylation route to the silphenylene polymers of the invention, and possibly special synthesis strategies that allow for the composition of the invention. Overall, it can therefore be stated that the hydrosilylation reaction is, in principle, applicable to obtain the silphenylene polymers of the invention, but involves considerable additional effort compared to processes such as the Wurtz or Grignard synthesis.

[0058] Therefore, the hydrosilylation reaction is not preferred as a synthesis route for the silphenylene polymers of the invention, in contrast to the silphenylene-silalkylene polymers and silphenylene siloxane copolymers described in the known prior art. The novel prior art described here is best realized using a process that deviates from the preferred process according to the already known prior art.

[0059] The preferred process for producing the silphenylene polymers of the invention involves magnesium-mediated Si-C bond formation in the manner of a Grignard reaction. This process makes it possible to obtain the silphenylene polymers of the invention in a single process step and thus with maximum cost-effectiveness and the required purity.

[0060] For the preferred process for preparing the silphenylene polymers according to the invention, silicon-containing compounds of the formulas (IV), (V) and (VI) are used, R 15< h R 16< i Si (IV), R 15< j R 16< k Si[SiR l 17< R m 18< ] n SiR j 15< R k 16< (V), R 15< j R 16< k Si[SiR l 17< R m 18< ] n -X 1< -[SiR l 17< R m 18< ] n SiR 15< j R 16< k (VI), where R 15< is a halogen atom or a C1 - C3 alkoxy group, preferably a chlorine, bromine or iodine atom or a methoxy radical, in particular a Cl atom or a methoxy radical, where several radicals R 15< can be different radicals from the specified group, in particular several radicals R 15< in the same molecule can be both a halogen radical and an alkoxy radical and R 16< , R 17< and R 18< can independently of one another be radicals from the group of the radicals R, R 1< , R 2< or R 3<, but not a radical of the formula (II) and R 18< can additionally be a halogen radical or a C1 - C3 alkoxy radical, where the radicals R 16< , R 17< and R 18< do not contain any functional groups which are carbonyl or carboxyl groups, hydroxy groups, doubly bonded nitrogen atoms, primary, secondary or tertiary amine groups or thiol groups, so that the residues R 16< , R 17< and R 18< are inert towards magnesium.

[0061] X 1< means a chemical bond or a magnesium-inert divalent bridging aliphatic, cycloalkylaliphatic, cycloalkylaromatic or alkylaromatic hydrocarbon radical which does not contain any functional groups comprising carbonyl or carboxyl groups, hydroxy groups, doubly bonded nitrogen atoms, primary, secondary or tertiary amine groups or thiol groups, which has been formed by hydrosilylation of a hydrosilylatable olefinically or acetylenically unsaturated precursor Z of the formula R 19< -X 2< -R 19<, in which R 19< means an olefinically or acetylenically unsaturated hydrosilylatable C2 - C8 radical and X 2< means the radical X 1< shortened on both sides by the C2 - C8.Examples of cycloaliphatic, cycloaromatic or aromatic hydrocarbon radicals X 2< are those already listed for Y with the restriction that for X 2< only those radicals from the group of radicals Y are permitted which are inert towards magnesium. h is an integer with a value of 1, 2, 3 or 4, preferably 1, 2 or 3 and i is an integer with a value of 0, 1, 2 or 3 and the sum h + i = 4. j is a number with a value of 0, 1, 2 or 3, where j has the value 1 on at least one terminal Si atom of the di-, oligo- or polysilane of the formula (V), so that at least one radical R 15< is always present per molecule of the formula (V), k is an integer with a value of 0, 1, 2 or 3, where k + j = 3. l and m each represent a number with a value of 0, 1 or 2, where l + m = 2. n is a number with a value of 0 to 50, preferably 0 - 30.

[0062] The compounds of formula (VI) which contain a radical X 1< which is bonded to the Si atoms delimiting it by hydrosilylation are preferably obtained by hydrosilylation of the precursor Z with Si-H-functional silicon-containing compounds of formula (VII), R 15< j R 16< k Si[SiR l 17< R m 18< ] n -H (VII), where R 15< , R 16< , R 17< and R 18< , and also j, k, l and m have the meanings given above and H is a hydrogen atom. For n = 0, (VII) is a halogenated silane or an alkoxysilane, for n > 0, (VII) is a halogenated or alkoxylated di-, oligo or polysilane. Mixed forms are also conceivable, where R 15< is both a halogen radical and an alkoxy radical in the same molecule.

[0063] In addition to being used as raw materials for the preparation of compounds of formula (VI), the compounds of formula (VII) can also be used for the preparation of the silphenylene polymers according to the invention, whereby they can participate in the Grignard reaction preferably used for the preparation of the silphenylene polymers according to the invention through the halogen radicals or the alkoxy radicals.

[0064] Typische Beispiele für Silane der Formel (IV) sind Methyltrichlorsilan, Methyltrimethoxysilan, Methyltriethoxysilan, Dimethyldichlorsilan, Dimethyldichlorsilan, Dimethyldiethoxysilan, Trimethylchlorsilan, Trimethylmethoxysilan, Trimethylethoxysilan, Trimethylsilanol, Phenyltrichlorsilan, Phenyltrimethoxysilan, Phenyltriethoxysilan, Phenylmethyldichlorsilan, Phenylmethyldimethoxysilan, Phenylmethyldiethoxysilan, Diphenyldichlorsilan, Diphenyldimethoxysilan, Diphenyldiethoxysilan, Triphenylchlorsilan, Triphenylmethoxysilan, Triphenylethoxysilan, Diphenylmethylchlorsilan, Diphenylmethoxysilan, Diphenylmethyldiethoxysilan, Phenyldimethylchlorsilan, Phenyldimethylmethoxysilan, Phenyldimethylethoxysilan, Vinyltrichlorsilan, Vinyltrimethoxysilan, Vinyltriethoxysilan, Vinyldimethylchlorsilan, Vinyldimethylmethoxysilan und Vinyldimethylethoxysilan, Trichlorsilan, Trimethoxysilan, Triethoxysilan, Methyldichlorsilan, Methyldimethoxysilan, Methyldiethoxysilan, Dimethylchlorsilan,Dimethylmethoxysilane, dimethylethoxysilane, ethyltrichlorosilane, ethyltrimethoxysilane, ethyltriethoxysilane, and tetrachlorosilane. Particularly preferred silanes of formula (IV) are methyltrichlorosilane, methyltrimethoxysilane, dimethyldichlorosilane, dimethyldimethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyldimethylchlorosilane, vinyldimethylmethoxysilane, phenyltrichlorosilane, phenyltrimethoxysilane, phenylmethyldichlorosilane, and phenylmethyldimethoxysilane. The silanes of formula (IV) can also be used as mixtures. For example, it is preferred to use mixtures of silanes mixed with terminating silanes for chain formation and crosslinking. The list of examples is illustrative, not limiting.

[0065] Typische Beispiele für Di-, Oligo- und Polysilane der Formel (V) sind Hexachlordisilan, Hexamethoxydisilan, Hexaethoxydisilan, Dimethyltetrachlordisilan, Dimethyltetramethoxydisilan, Dimethyltetraethoxydisilan, Trimethyltrichlordisilan, Trimethyltrimethoxydisilan, Trimethyltriethoxydisilan, Tetramethyldichlordisilan, Tetramethyldimethoxydisilan, Tetramethyldiethoxydisilan, Dimethylvinyltrichlordisilan, Dimethylvinyltrimethoxydisilan, Dimethylvinyltriethoxydisilan, Diphenyltetrachlordisilan, Diphenyltrimethoxydisilan, Diphenyltetraethoxydisilan, Diphenylvinyltrichlordisilan, Diphenylvinyltrimethoxydisilan, Diphenylvinyltriethoxydisilan, Tetravinyldichlordisilan, Tetravinyldimethoxydisilan, Tetravinyldiethoxydisilan, Divinyltetrachlordisilan, Tetravinyldimethoxydisilan, Tetravinyldiethoxydisilan, Trimethyldichlordisilan, Trimethyldimethoxydisilan, Trimethyldiethoxydisilan, Octachlortrisilan, Octamethoxytrisilan, Octaethoxytrisilan, Tetramethyltetrachlortrisilan,Tetramethyltetramethoxytrisilan, Tetramethyltetraethoxytrisilan, Hexamethyldichlortrisilan, Hexamethyldimethoxytrisilan, Hexamethyldiethoxytrisilan, Pentamethyltrichlortrisilan, Pentamethyltrimethoxytrisilan, Pentamethyltriethoxytrisilan, Diphenyldivinyltetrachlortrisilan, Diphenyldivinyltetramethoxytrisilan, Diphenyldivinyltetraethoxytrisilan, Diphenyldimethylvinyltrichlortrisilan, Diphenyldimethylvinyltrimethoxytrisilan, Diphenyldimethylvinyltriehoxytrisilan, Tetramethyltrichlortrisilan, Tetramethyltrimethoxytrisilan, Tetramethyltriethoxytrisilan, Hexamethylchlortrisilan, Hexamethylmethoxytrisilan, Hexamethylethoxytrisilan, Pentamethyldichlortrisilan, Pentamethyldimethoxytrisilan, Pentamethyldiethoxytrisilan, Diphenyldivinyltrichlortrisilan, Diphenyldivinyltrimethoxytrisilan, Diphenyldivinyltriethoxytrisilan, Diphenyldimethylvinyldichlortrisilan, Diphenyldimethylvinyldimethoxytrisilan, Diphenyldimethylvinyldiehoxytrisilan, Nonamethylnonachloroctasilan, Nonamethylnonamethoxyoctasilan,Nonamethylnonaethoxyoctasilane, heptamethyldiphenylnonachlorooctasilane, heptamethyldiphenylnonamethoxyoctasilane, heptamethyldiphenylnonaethoxyoctasilane, heptamethyldiphenyldivinylheptachlorooctasilane, heptamethyldiphenyldivinylheptamethoxyoctasilane, heptamethyldiphenyldivinylheptaethoxyoctasilane, heptamethyltetraphenylheptachlorooctasilane, heptamethyltetraphenylheptamethoxyoctasilane, heptamethyltetraphenylheptaethoxyoctasilane, where the methyl, phenyl, ethyl, vinyl, and Si-H groups and the chlorine, methoxy, and ethoxy groups can be randomly distributed among the silicon atoms, subject to the rule that each Si atom is tetravalent. This list is illustrative, not restrictive. Instead of Si atoms substituted purely by clatoms, methoxy or ethoxy groups, mixed Cl-, methoxy- and / or ethoxy-functional representatives are also possible in the example molecules of formula (V), which are also typical examples.

[0066] Typische Beispiele für Di-, Oligo- und Polycarbosilane der Formel (VI) sind Cl(CH 3 ) 2 Si-CH 2 CH 2 -Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-CH 2 CH 2 -Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-CH 2 CH 2 -Si(CH 3 )Cl 2 , Cl 2 (CH 3 )Si-CH 2 CH 2 2 -SiCl 3 , Cl(CH 3 ) 2 Si-CH=CH-Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-CH=CH-Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-CH=CH-Si(CH 3 )Cl 2 , Cl 3 Si-CH=CH-SiCl 3 , Cl(CH 3 ) 2 Si-(CH 3 ) ) 3 (C 6 H 4 )(CH 2 ) 3 -Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -Si(CH 2 )Cl 2 , Cl 3 Si-(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -SiCl 3 , Cl(CH 3 )Si-Si(CH 3 ) 2 -(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -(CH 3 ) 2 Si-Si(CH 3 ) 2 Cl, Cl(CH 3 ) 2 Si-(CH 2 ) 3 (C 6 H 4 )-(C 6 H 4 )(CH 2 ) 3 -Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-(CH 2 ) 3 (C 6 H 4 )-(C 6 H 4 )(CH 2 ) 3 -Si(CH 3 ) 2 Cl, Cl 2 (CH 3 )Si-(CH 2 ) 3 (C 6 H 4 )-(C 6 H 4 )(CH 2 ) 3 -Si(CH 3 )Cl 2 , Cl 3 Si-(CH 2 ) 3 (C 6 H 4 )-(C 6 H 4 )(CH 2 ) 3 -SiCl 3 ,Cl(CH 3 ) 2 Si-CH 2 CH 2 -Si(CH 3 )(CH=CH 2 )Cl, Cl(CH 3 )(CH=CH 2 )Si-CH 2 CH 2 -Si(CH 3 )(CH=CH 2 )Cl, Cl(CH 3 )(CH=CH 2 )Si-(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -Si(CH 3 )(CH=CH 2 )Cl, Cl(CH=CH 2 ) 2 Si-(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -Si(CH=CH 2 ) 2 Cl, Cl(CH 3 )(H)Si-(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -Si(CH 3 )(H)Cl, Cl(H) 2 Si-(CH 2 ) 3 (C 6 H 4 )(CH 2 ) 3 -Si(H) 2 Cl, where methoxy groups or ethoxy groups may be present in the example molecules of formula (VI) instead of the chlorine atoms; if appropriate, mixed Cl-, methoxy-, and / or ethoxy-functional representatives may also be formed, which also belong to the typical examples. The list is illustrative and not limiting.

[0067] Organic raw materials suitable for preparing the silphenylenes according to the invention are those of the formula (VIII) [Hal] o -Y (VIII), where Hal represents a Cl, Br or iodine atom, preferably a Cl or Br atom, o represents a number from 2 to 12, preferably 2, and Y has the meanings given above.

[0068] Typical examples of organic raw materials of formula (VIII) result from the list of examples for the radical Y, in which the free valences are saturated with halogen atoms. Particularly preferred representatives of the formula (VIII) are dihalobenzenes, such as 1,4-dibromobenzene, 1,4-dichlorobenzene, 1,2-dichlorobenzene, 1,2-dibromobenzene, 1,2-dichloroethane, 1,2-dibromoethane, 1,1-dichloroethane, 1,1-dibromoethane, 1,4-dichlorobutane, 1,4 Dibromobutane, 1,3-dichlorobutane, 1,3-dibromobutane, 1,5-dichloropentane, 1,5-dibromopentane, 1,6-dichlorohexane, 1,6-dibromohexane, 1,7-dichloroheptane, 1,7-dibromoheptane, 1,8-dichlorooctane, 1,8-dibromooctane, 1,9-dichlorononane, 1,9-dibromononane, 1,10-Dichlorodecane, 1,10-Dibromodidecane, 1,11-Dichlorundecane, 1,11-Dibromundecane, 1,12-Dichlorododecane, 1,12-Dibromododecane, 1,2-Dichlorodiphenylethane, 1,2-Dibromodiphenylethane, 1,2-Dichlorocyclohexylethane, 1,2-Dibromocyclohexylethane, 2-Methyl-1,4-Dichlorobenzene, 2-Methyl-1,4-Dibromobenzene, 2-Methoxy-1,4-Dichlorobenzene, 2-Methoxy-1,4-Dibromobenzene,2-Ethyl-1,4-Dichlorbenzol, 2-Ethyl-1,4-Dibrombenzol, 2-Ethoxy-1,4-Dichlorbenzol, 2-Ethoxy-1,4-Dibrombenzol, 2- n< Propyl-1,4-Dichlorbenzol, 2- n< Propyl-1,4-Dibrombenzol, 2- n< Propoxy-1,4-Dichlorbenzol, 2- n< Propoxy-1,4-Dibrombenzol, 2- iso< Propyl-1,4-Dichlorbenzol, 2- iso< Propyl-1,4-Dibrombenzol, 2- n< Butyl-1,4-Dichlorbenzol, 2- n< Butyl-1,4-Dibrombenzol, 2- sec< Butyl-1,4-Dichlorbenzol, 2- sec< Butyl-1,4-Dibrombenzol, 2- tert.< Butyl-1,4-Dichlorbenzol, 2- tert.< Butyl-1,4-Dibrombenzol, polyhalogenierte Biphenylene wie Dibrombiphenyl, Tribrombiphenyl, Tetrabrombiphenyl, Pentabrombiphenyl, Hexabrombiphenyl, Heptabrombiphenyl, Octabrombiphenyl, Nonabrombiphenyl, Decabrombiphenyl und die entsprechenden mehrfach chlorierten Biphenylenanalogen, 4-Chlorbenzhydrylchlorid, 4-Brombenzhydrylbromid, Diphenyldichlormethan, Diphenyldibrommethan, 1,2-Diphenyl-1,2-dichlorethan, 1,2-Diphenyl-1,2-dibromethan, 1,1'-(2,2,2-Trichloroethan-1,1-diyl)bis(4-chlorobenzol), Hexachlorcyclohexan, 1,2,4,5,6,7,8,8-Octachlor-3a,4,7,7a-tetrahydro-4,7-methano-indane (chlordane), 1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-1,4-endo-5,8-exo-dimethanonaphthalene (Dieldrin), 1-Bromo-4-Chlorobenzene, 4,4'-(Propane-2,2-diyl)bis(2,6-dibromophenol) (Tetrabromobisphenol A), 3,5,3',5'-Tetrachlorobisphenol A.,

[0069] Preferred representatives of formula (VIII) are 1,4-dibromobenzene, 1,4-dichlorobenzene, 1,2-dichloroethane, and 1,2-dibromoethane. Mixtures of different representatives of formula (VIII) can optionally be used.

[0070] Like all other lists of typical examples, this list is intended to be illustrative and not restrictive. Magnesium, as a metal, is best used in forms with a large surface area, such as chips, grains, or powder. Magnesium is preferably used in a minimum amount, which is determined by the following equation: p = (q / 2) + r.

[0071] Where p is the number of moles of magnesium, q is the number of halogen and alkoxy equivalents from the compounds (IV), (V), (VI), (VII) and (VIII) and r is a value between 0 and half the amount of halogen and alkoxy equivalents from the compounds (IV), (V), (VI), (VII) and (VIII) used in each case, whereby the value 0 for r is not included. This means that r is always greater than zero and has a maximum value of q / 2. Magnesium is used in excess of the number of halogen atoms and alkoxy groups.

[0072] To facilitate the reaction, the preferred process for preparing the silphenylene polymers of the invention employs solvents that are inert toward the reactants. In principle, the substances commonly used as inert solvents in the reaction of metals with organohalogen compounds, in particular ethers such as diethyl ether, di-n-butyl ether, tert-butyl methyl ether, tetrahydrofuran, 1,4-dioxane, or hexamethylphosphoric triamide, can be used, optionally also in admixture with one another and optionally also in admixture with other inert solvents such as toluene, xylene, or ethylbenzene. However, it must be ensured that the solvents used are actually inert toward the reactants.For example, it has been found that Si-Cl-containing components of formulas (IV), (V), (VI), and (VII) react with THF to open the ring, forming butoxy groups that react with the resulting silphenylene polymers and form undesired alkoxy groups that can, in principle, undergo hydrolysis to form silanol groups, which in turn can condense to form likewise undesired Si-O-Si units. As will be seen later, the workup is carried out in aqueous solution, optionally using acids such as hydrochloric acid, so that this reaction is conceivable during workup. This side reaction would not result in the obtaining of silphenylene-polysiloxane copolymers according to the invention.

[0073] In the prior art, which aims at the production of silphenylene-polysiloxane polymers containing polysiloxane units, such as according to US3350350 A, this fact is not taken into account, since the formation of siloxane units does not conflict with the inventiveness there. However, this is different in the present case, which in detail explains the novelty of the selected process for producing the silphenylene polymers according to the invention. In the present case, only those solvents which are inert towards chlorosilanes, such as 1,4-dioxane and hexamethylphosphoric triamide, are suitable for use with Si-Cl-containing components of the formulas (IV), (V), (VI) and (VII). The use of THF, for example, is possible, but only together with alkoxy-functional components of the formulas (IV), (V), (VI) and (VII).

[0074] The preferred process for preparing the silphenylene polymers according to the invention is preferably carried out at temperatures from -78°C to 150°C under atmospheric pressure. Higher or lower pressures can also be used if necessary. The process is expediently carried out in an atmosphere of nitrogen or argon that is inert to the reactants. In particular, the ingress of water as a liquid, vapor, or coating on vessels, as well as the magnesium, is to be excluded as best as possible by applying suitable measures according to the state of the art, such as baking under vacuum.

[0075] The preferred process for preparing the silphenylene polymers according to the invention is preferably carried out stepwise by first reacting component (VIII) with magnesium and, in a second step, reacting the required selection of components (IV), (V), (VI), and (VII). However, the process can also be carried out in one step by reacting the components of formula (VIII) in the presence of the required selection of components of formula (IV), (V), (VI), and optionally (VII). To activate the magnesium, advantageously, a portion of component (VIII), for example 10% by weight of the total amount of component (VIII), is first combined with the magnesium.

[0076] The isolation of the reaction products obtained in the preferred process can be carried out in the same way as is customary for the isolation of reaction products obtained in organometallic syntheses, in particular Grignard syntheses. The resulting reaction mixtures are preferably mixed with water at 0 to 30°C. Since hydrochloric acid is formed from any remaining Si-Cl groups and silanol groups are formed, which lead to condensation and the formation of Si-O-Si units, both of which are undesirable, the most complete possible conversion of all halogen radicals involved in the reaction must be ensured before workup. The same applies to Si-bonded alkoxy groups still present during the addition of water. These can also hydrolyze and form silanol groups capable of condensation.For this reason, in contrast to Grignard-analog syntheses according to the prior art, for example, for the preparation of polysilarylenesiloxanes according to US 3350350 A, in this case, the amount of magnesium used is not equivalent to the amount of halogen atoms and alkoxy groups used, but rather an excess of magnesium. If necessary, an acid can be used for workup, such as hydrochloric acid, to adjust the pH or to promote the formation of magnesium halides.

[0077] The water-soluble salt components are extracted aqueously, and solids such as any insoluble components of magnesium or magnesium salts are removed using state-of-the-art methods, for example by filtration or centrifugation.

[0078] The volatile components of the reaction mixture are removed using state-of-the-art methods, such as continuous or discontinuous distillation, to obtain the reaction products in pure form. If the reaction products are desired as a preparation in a solvent, they can be subsequently dissolved in the solvent of choice or obtained directly from the reaction solvent as the desired preparation by solvent exchange. The solvent exchange is also carried out using state-of-the-art methods.

[0079] If it is desired to further modify the silphenylene polymers primarily obtained from the preferred process, for example by introducing functional groups that are not stable under the conditions of the Grignard synthesis, it may be advantageous to introduce suitable functional groups into the primary silphenylene polymer in the Grignard-analog synthesis step. It should be noted that the primarily obtained silphenylene polymers as such already fulfill all the features of the invention and are therefore in accordance with the present invention. It is known from the prior art that Grignard reactions convert the carbonyl groups of aldehydes, ketones, and carboxylic acids, as well as their esters, into alcohols.Therefore, if carbinol groups are desired for the subsequent introduction of functional groups, the use of correspondingly carbinol-functional starting materials, as well as the use of carbonyl- or epoxy-functional starting materials, for example by selecting a suitable component according to formula (VIII), would be a possible option. Since Grignard reagent is consumed both in the presence of alcohol and during the conversion of the carbonyl groups, the increased demand for Grignard reagent must be taken into account. Since this procedure could potentially compromise the economic viability of the process, this procedure is not preferred, although it is fundamentally possible and therefore included in the invention.

[0080] By reacting acrylic acid, methacrylic acid, or chloropropionyl chloride with such a carbonyl group, it is possible, for example, to introduce an acrylate group or a methacrylate group into a silphenylene polymer according to the invention. In the case of the reaction with the acid chlorides of methacrylic acid and acrylic acid, the corresponding methacrylic acid or acrylic acid ester is formed after elimination of HCl, which can optionally be promoted with a suitable, for example, tertiary amine. In the case of chloropropionyl chloride, the ester of chloropropionic acid is formed in the first step, from which the acrylic acid residue is formed in the second step by basic workup, for example with a tertiary amine and HCl elimination from the propionyl chloride residue. All reactions are, as such, state of the art and therefore not new per se.However, their use for producing the silphenylene polymers according to the invention is new, which is why these steps are also included in the scope of the invention as part of the preferred process for producing the silphenylene polymers according to the invention.

[0081] The silphenylene polymers of formula (I) all possess at least olefinically or acetylenically unsaturated functional groups, via which they are chemically crosslinkable. Possible chemical crosslinking reactions include the known reactions according to the prior art, in particular radical crosslinking, which can be initiated using suitable radiation sources such as UV light, as well as by unstable chemical compounds that decompose to form radicals, and addition crosslinking, for example, by hydrosilylation of the olefinically unsaturated group with an Si-H function in the presence of a suitable hydrosilylation catalyst. The Si-H functions can also be bound to the silphenylene polymers according to the invention.

[0082] In order to achieve sufficient curing, a sufficient amount of functional groups must be present. At least 1.0 functional groups on average must be present per silphenylene polymer molecule used according to the invention in order to achieve sufficient curing; preferably, at least 1.1, in particular at least 1.2, functional groups on average are present per silphenylene polymer molecule according to the invention. The functional groups can be different, so that, for example, some of the functional groups are an Si-H group and another part of the functional groups represents an olefinically unsaturated group that is radically curable or hydrosilylatable. Other combinations of complementary functional groups are also conceivable, where complementary means that the selected combinations of functional groups can react with one another.If only one type of functional group is present, for example, only olefinically or acetylenically unsaturated functional groups that are radically curable, the corresponding number of these functional groups must be present. For copolymerization to form a homogeneous matrix, it is important to ensure sufficient copolymerizability of the selected olefinic and acetylenic groups. The combination of olefinic groups that are not copolymerizable with each other is also possible, provided the resulting matrix of two or more individual polymers remains compatible with each other and does not form separate phases that separate into distinct domains.

[0083] Examples of suitable initiators for starting radical polymerization include, in particular, examples from the field of organic peroxides, such as di-tert-butyl peroxide, dilauryl peroxide, dibenzoyl peroxide, dicumyl peroxide, cumyl peroxyneodecanoate, tert-butyl peroxyneodecanoate, tert-amyl peroxypivalate, tert-butyl peroxypivalate, tert-butyl peroxyisobutyrate, tert-butyl peroxy-3,5,5-trimethylhexanoate, tert-butyl cumyl peroxide, tert-butyl peroxyacetate, tert-butyl peroxybenzoate, 1,1-ditert-butylperoxycyclohexane, 2,2-di(tert-butylperoxy)butane, bis(4-tert-butylcyclohexyl)peroxydicarbonate, hexadecyl peroxydicarbonate, tetradecyl peroxydicarbonate, dibenzyl peroxydicarbonate, Diisopropylbenzene, dihydroperoxide, [1,3-phenylenebis(1-methylethylidene)]bis[tert-butyl]peroxide, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane, dicetyl peroxydicarbonate, acetylacetone peroxide, acetylcyclohexanesulfonyl peroxide, tert.Amyl hydroperoxide, tert-amyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxyisopropyl carbonate, tert-amyl peroxyneodecanate, tert-amyl peroxy-3,5,5-trimethylhexanoate, tert-butyl monoperoxymaleate; this list is illustrative only and not limiting. If necessary, mixtures of different initiators can also be used for radical reactions.

[0084] The suitability of an initiator or initiator mixture for radical reactions depends on its decomposition kinetics and the required conditions to be met. With sufficient consideration of these general conditions, the expert will be able to select a suitable initiator.

[0085] For preparations that contain silicon-bonded hydrogen in addition to olefinically and acetylenically unsaturated groups, curing by a hydrosilylation reaction is possible. Suitable catalysts for promoting the hydrosilylation reaction are known catalysts from the state of the art.

[0086] Examples of such catalysts are compounds or complexes of the noble metal group containing platinum, ruthenium, iridium, rhodium, and palladium, preferably metal catalysts from the platinum group or compounds and complexes from the platinum group. Examples of such catalysts are metallic and finely divided platinum, which can be on supports such as silicon dioxide, aluminum oxide, or activated carbon, compounds or complexes of platinum such as platinum halides, e.g.PtCl 4 , H 2 PtCl 6 x6H 2 O, Na 2 PtCl 4 x4H 2 O, platinum-olefin complexes, platinum-alcohol complexes, platinum-alcoholate complexes, platinum-ether complexes, platinum-aldehyde complexes, platinum-ketone complexes, including reaction products of H 2 PtCl 4 x6H 2 O and cyclohexanone, platinum-vinyl-siloxane complexes, such as platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane, with or without detectable inorganically bound halogen, bis-(gamma-picoline)platinum chloride, trimethylenedipyridineplatinum chloride, dicyclopentadieneplatinum dichloride, dimethylsulfoxyethenylplatinum(II) dichloride, cyclooctadieneplatinum dichloride, norbornadieneplatinum dichloride, gammapicolineplatinum dichloride, Cyclopentadiene platinum dichloride, as well as reaction products of platinum tetrachloride with olefin and primary or secondary amine or primary and secondary amine such as the reaction product of platinum tetrachloride dissolved in 1-octene with sec-butylamine or ammonium platinum complexes.In a further embodiment of the process according to the invention, complexes of iridium with cyclooctadienes, such as µ-dichloro-bis(cyclooctadiene)-diiridium(I), are used.

[0087] This list is illustrative and not limiting. The development of hydrosilylation catalysts is a dynamic field of research that continually produces new, effective species that can naturally also be used in this field.

[0088] The hydrosilylation catalyst preferably comprises compounds or complexes of platinum, preferably platinum chlorides and platinum complexes, in particular platinum-olefin complexes and particularly preferably platinum-divinyltetramethyldisiloxane complexes.

[0089] In the process according to the invention, the hydrosilylation catalyst is used in amounts of 2 to 250 ppm by weight, preferably in amounts of 3 to 150 ppm, in particular in amounts of 3 to 50 ppm.

[0090] In a preferred embodiment, the silphenylene polymers of formula (I) are applied to a metal substrate in a third step.

[0091] The silphenylene polymers of formula (I) are particularly suitable for use as binders and / or adhesion promoters for the production of metal-clad laminates, particularly for electronic applications, especially for metal-clad laminates and especially for use in high-frequency applications, especially those operating at frequencies of 1 GHz and above. Particular preference is given to the production of metal-clad electrical laminates, such as those used for the manufacture of printed circuit boards in electronic devices, especially for high-frequency applications.

[0092] These metal-clad electrical laminates may, but do not have to, contain reinforcing materials. This means they may, for example, contain reinforcing fabrics such as fiber fabrics or nonwovens, or they may be free of them. If a reinforcing material is included, it is preferably arranged in layers. A reinforcing layer can be composed of a variety of different fibers.

[0093] Such reinforcing layers help to control shrinkage behavior and provide increased mechanical strength.

[0094] If a reinforcing layer is used, the fibers forming this layer can be selected from a wide variety of options. Non-limiting examples of such fibers include glass fibers, such as E-glass fibers, S-glass fibers, and D-glass fibers; silica fibers; polymer fibers, such as polyetherimide fibers, polysulfone fibers, polyetherketone fibers, polyester fibers, polycarbonate fibers, aromatic polyamide fibers, or liquid crystalline fibers. The fibers can have a diameter of 10 nm to 10 µm. The reinforcing layer has a thickness of at most 200 µm, preferably at most 150 µm.

[0095] A preferred application is the use of the silphenylene polymers of formula (I) as binders or co-binders together with organic binders for the production of metal-clad laminates from glass fiber composites for the further production of printed circuit boards. The preferred metal is copper.

[0096] For the inventive use of the silphenylene polymers of formula (I), these can be used as the sole binder. They can also be used blended with organic monomers, oligomers, and polymers. Organic monomers, oligomers, and polymers typically used for this purpose include polyphenylene ethers, bismaleimides, bismaleimide triazine copolymers, hydrocarbon resins, both aliphatic such as polybutadiene, and aromatic such as polystyrene, as well as hybrid systems that have both aliphatic and aromatic character, such as styrene-polyolefin copolymers (the form of the copolymers is fundamentally not restricted), epoxy resins, cyanate ester resins, and optionally others, the selection being understood to be illustrative and not restrictive.

[0097] Preferred organic monomers, oligomers, and polymers are oligomeric and polymeric polyphenylene ethers, monomeric, oligomeric, and polymeric bismaleimides, oligomeric and polymeric hydrocarbon resins, and bismaleimide triazine copolymers. The organic monomers, oligomers, and polymers can optionally be used in admixture with one another.

[0098] The proportion of organic monomers, oligomers and polymers in the preparations with the silphenylene polymers of the formula (I), if the organic components are used, is between 10 and 90% based on the mixture of the silphenylene polymers of the formula (I) and the organic monomers, oligomers and polymers as 100%, preferably 20 - 90%, in particular 30 - 80%.

[0099] In addition, both the silphenylene polymers of formula (I) and the mixtures thereof with organic monomers, oligomers or polymers can be dissolved in further organic monomers, optionally with olefinically or acetylenically unsaturated groups, as reactive diluents, such as styrene, alpha-methylstyrene, para-methylstyrene and vinylstyrene, chloro- and bromostyrene.

[0100] Likewise, typical non-reactive solvents can be used to dissolve the silphenylene polymers of the formula (I) and optionally mixtures thereof with organic monomers, oligomers and polymers, such as, for example, aliphatic or aromatic solvents such as aliphatic mixtures with certain boiling ranges, toluene, xylene, ethylbenzene or mixtures of the same aromatics, ketones such as acetone, methyl ethyl ketone, cyclohexanone, carboxylic acid esters such as ethyl acetate, methyl acetate, ethyl formate, methyl formate, propionic acid methyl ester, propionic acid ethyl ester, wherein good solubility in particular of the mixtures of silphenylene polymers of the formula (I) with organic monomers, oligomers and polymers is most easily achieved in aromatic solvents such as toluene, xylene, ethylbenzene and mixtures thereof.

[0101] In the case where the silphenylene polymers of formula (I) are used in combination with an organic oligomer or polymer, or mixtures thereof, it is essential that silphenylene polymers of formula (I) are used that are compatible with the organic components of choice and do not lead to phase separation. In these cases, silphenylene polymers of formula (I) with a higher phenyl content should generally be used, since phenyl groups increase compatibility with the organic components. Especially with organic polymers rich in aromatics, such as polyphenylene ethers or aromatic hydrocarbon resins, silphenylene polymers of formula (I) with a higher aromatic content should be used, with both the bridging aromatic groups and aromatic substituents terminally bonded to silyl units contributing to the compatibility adjustment.

[0102] The exact amount of aromatic groups necessary to adjust the compatibility of the silphenylene polymers of formula (I) with a specific selection of organic binders must be determined depending on the selection of organic binders.

[0103] Just as it is possible to mix a plurality of organic polymers, which are optionally selected from different polymer classes, and to use them in the binder preparation. It is also possible to combine a plurality of silphenylene polymers of the formula (I) with one another in a binder preparation. This means that according to the invention, only a single silphenylene polymer of the formula (I) can be used as a binder, and several silphenylene polymers of the formula (I) can be combined with one another to form a binder preparation. Likewise, according to the invention, only one silphenylene polymer of the formula (I) can be combined with one or more organic polymers to form a binder preparation. It is also possible according to the invention to combine a plurality of silphenylene polymers of the formula (I) with one or more different organic polymers to form a binder preparation.

[0104] The compatibility of one or more silphenylene polymers of formula (I) with one or more organic oligomers or polymers can be easily determined by mixing a mixture of the organic binder(s) with the silphenylene polymer(s) of formula (I), advantageously in a solvent that dissolves all selected components. The solvent is then removed using state-of-the-art methods, for example, by distillation or spray drying. The resulting residue is evaluated visually or with the aid of microscopic, optionally electron microscopic, methods. Compatible mixtures can be recognized by the fact that no silphenylene polymer domains separate from the organic components and are recognizable as a separate phase.

[0105] The use of additional formulation components, such as additives, which may optionally also include silanes, such as antifoams and deaerating agents, wetting and dispersing agents, flow control agents, compatibilizers, adhesion promoters, curing initiators, catalysts, stabilizers, fillers including pigments, dyes, inhibitors, flame retardants, crosslinking aids, etc., is permitted according to the invention, and the selection of such components is fundamentally unrestricted. In addition to compatibility tests in the sense of suitable miscibility behavior, compatibility tests with regard to reactivity may also be necessary to prevent premature gelling and to ensure that sufficiently rapid polymerization or copolymerization of all components is achieved during curing, as well as tests for adequate wetting and, if appropriate, other properties.This must be taken into account when drafting the text.

[0106] Examples of usable fillers are ceramic fillers such as silicas, for example precipitated silicas or pyrogenic silicas, which can be both hydrophilic and hydrophobic and are preferably hydrophobic and which can furthermore also be functionally and optionally reactively provided with organic groups on their surface, quartz, which can optionally be surface-treated or surface-functionalized so that it can carry reactive functional groups on the surface, aluminum oxides, aluminum hydroxides, calcium carbonate, talc, mica, clay, kaolin, magnesium sulfate, carbon black, titanium dioxide, zinc oxides, antimony trioxide, barium titanate, strontium titanate, corundum, wollastonite, zirconium tungstate, ceramic hollow spheres, aluminum nitride, silicon carbide, beryllium oxide, magnesium oxide, magnesium hydroxide, solid glass spheres, hollow glass spheres and boron nitride.Core-shell particles made of various materials can be used as additional fillers, such as silicone resin spheres coated on the surface with silica, or polymer-coated elastomer particles, whereby the elastomer particles can optionally also be silicone elastomers, and a typical example of a surface coating of such an elastomer particle is a polymethyl methacrylate shell. The ceramic fillers preferably have particle sizes, expressed as a D 90 value, of 0.1 µm to 10 µm. Fillers are preferably present in amounts of 0.1 to 60 percent by weight, preferably 0.5 to 60 percent by weight, in particular 1 to 60 percent by weight, based on the total binder formulation consisting of binder(s), reactive monomers, additives, and fillers as 100%. This means that the amount of any non-reactive solvent used is not counted.

[0107] Among the fillers, those that are thermally conductive are particularly noteworthy. These include aluminum nitride, boron nitride, silicon carbide, diamond, graphite, beryllium oxide, zinc oxide, zirconium silicate, magnesium oxide, silicon oxide, and aluminum oxide.

[0108] In principle, the binder preparations can contain flame-retardant additives in an amount of typically 5 to 25 percent by weight. However, a special feature of the silphenylene polymers of formula (I) is that they reduce the need for flame-retardant additives, since the silphenylene polymers of formula (I) themselves already exhibit flame-retardant properties. Polyorganosiloxanes and siloxanes are known to exhibit flame-retardant properties, which are also found in the silphenylene polymers according to the invention, so that they themselves can be used as flame-retardant additives. It is therefore a particular advantage of the present invention that it succeeds in combining the function of the binder with the function of flame retardancy. Depending on the amount of silphenylene polymers of formula (I) used, the amount of flame-retardant additives can therefore be reduced.At an amount of at least 20 percent by weight based on the total mixture of all binders and reactive organic monomers used, the amount of flame-retardant additives is preferably only 0 to 10 percent by weight, particularly preferably 0 to 8 percent by weight, in particular 0 to 5 percent by weight, ie it is possible to dispense with the use of a flame-retardant additive when using the silphenylene polymers of formula (I), depending on the selection of the additive and the amount used.

[0109] Typical examples of flame-retardant additives are hydrates of the metals Al, Mg, Ca, Fe, Zn, Ba, Cu, or Ni, and borates of Ba and Zn. The flame-retardant additives can be surface-treated and may optionally contain reactive groups on the surface. The flame-retardant additives can also be halogenated organic flame-retardant additives, such as hexachloroendomethylenetetrahydrophthalic acid, tetrabromophthalic acid, or dibromoneopentyl glycol. Examples of other flame-retardant additives include melamine cyanurate, phosphorus-containing components such as phosphinates, diphosphinates, phosphazenes, vinylphosphazenes, phosphonates, phosphaphenantrene oxides, and fine-grained melamine polyphosphates.

[0110] Other examples of brominated flame-retardant additives include bispentabromophenylethane, ethylenebistetrabromophthalimide, tetradecabromodiphenoxybenzene, decabromodiphenyl oxide, and brominated polysilsesquioxanes. Some flame-retardant additives enhance each other's effectiveness synergistically. This is the case, for example, with the combination of halogenated flame retardant additives with antimony trioxide.

[0111] Further examples of other components include antioxidants, stabilizers against degradation due to weathering, lubricants, plasticizers, coloring agents, phosphorescent or other agents for the purpose of marking and traceability and antistatic agents.

[0112] Preferably, the silphenylene polymers of formula (I) are crosslinked during the production of metal-clad laminates.

[0113] Crosslinking aids used include, in particular, polyunsaturated, radically curable or hydrosilylatable monomers and oligomers, as illustrated in the following non-limiting examples. These include, for example, diolefinically unsaturated components such as, for example, symmetrically olefinically unsaturated disubstituted disilanes, such as 1,1,2,2-tetramethyl-1,2-divinyldisilane, 1,1,2,2-tetramethyl-1,2-dipropylmethacryloyldisilane, diolefinically unsaturated disubstituted organic monomers or oligomers, such as, for example, conjugated and non-conjugated dienes, such as 1,9-decadiene and 1,3-butadiene. This also includes triply olefinically unsaturated monomers or oligomers such as 1,2,4-trivinylcyclohexane, triallyl cyanurates or triallyl isocyanurates, tri(meth)acrylates, such as trimethylolpropane trimethacrylate.

[0114] This also includes unsaturated substituted monomers and oligomers such as 2,2-bis[[(2-methyl-1-oxoallyl)-oxy]methyl]-1,3-propanediylbismethacrylate ( Pentaerythritol tetramethacrylate ), tetraallyl-cis,cis,cis,cis-1,2,3,4-cyclopentane tetracarboxylate, tetraallylsilane, glyoxalbis(diallylacetal).

[0115] Since hydrosilylation curing is also conceivable in addition to radical curing, multiply Si-H functional components can also act as crosslinkers, such as 1,1,2,2-tetramethyl-1,2-disilane, 1,4-bis(dimethylsilyl)benzene or multiply chain and / or terminal Si-H functional oligo- and polyorganosilanes.

[0116] Suitable catalysts or initiators for the radical curing of binder preparations made from silphenylene polymers of formula (I) and organic monomers, oligomers, and polymers are the same as those already mentioned above, i.e., in particular, peroxides. In addition, other radical initiators are suitable for initiating the radical curing of both the silphenylene polymers of formula (I) alone and the described binder preparations, such as azo components such as α,α'azobis(isobutyronitrile), redox initiators such as combinations of peroxides such as hydrogen peroxide and iron salts, or azides such as acetyl azide.

[0117] The silphenylene polymers of formula (I) or the preparations containing them can be used for the application according to the invention both in solvent-free and solvent-containing forms. They are generally used as solvent-containing preparations to facilitate the homogeneous distribution of all components of the formulation and the wetting and saturation of any reinforcing layer used. A reinforcing layer is generally included. This is preferably a glass fiber fabric. The saturation of the reinforcing layer can be achieved by impregnating the preparation. Various technical solutions are available for this, including continuous processes where appropriate, and their selection for producing the metal-clad laminates according to the invention is in no way restricted.Non-limiting examples of application techniques include dipping, optionally applying webs of reinforcing material via roller systems in continuous processes, spraying, flooding, doctoring, etc. An advantage of the present invention is that all available technologies can be applied without restriction or modification, and no special new process is required for the use of the silphenylene polymers of formula (I). In this respect, the present invention is entirely within the available state of the art in the production of metal-clad laminates. What is new is the use of the silphenylene polymers of formula (I) for the production of the metal-clad laminates in question, which was previously unknown.

[0118] Impregnation is followed by a drying step, in which any solvent used is removed. State-of-the-art methods are also used for the drying process. These include, in particular, thermally induced evaporation with or without vacuum. By appropriately adjusting the reactivity and tackiness of the binder mixture used, storable composite materials are obtained after this step under suitable conditions, such as cooling, which can be further processed at a later date if necessary.

[0119] In a final step of the process, the binder preparation is polymerized using state-of-the-art methods. Any initiators used for radical polymerization are heated above their decomposition temperature, causing them to decompose to form radicals and initiate radical polymerization of the binder preparation. Radiation curing methods are also generally applicable.

[0120] If hydrosilylation curing is used instead of radical polymerization, a temperature must be applied in this step that is suitable for deactivating the inhibitor used with the hydrosilylation catalyst and releasing the catalytic activity of the hydrosilylation catalyst.

[0121] This step is generally carried out at elevated temperature, preferably from 100 to 390°C, more preferably from 100 to 250°C, especially from 130 to 200°C, with the temperature being effective for a time of preferably 5 to 180 minutes, more preferably 5 to 150 minutes, especially 10 to 120 minutes. Furthermore, it is customary to apply elevated pressure during this step. Typical pressures are in the range of 1 to 10 MPa, more preferably 1 to 5 MPa, especially 1 to 3 MPa.

[0122] The lamination of the composite material with a conductive metal layer occurs in this second step by applying a layer of at least one selected metal to one or both sides of the composite material consisting of the reinforcement layer and binder preparation before curing. This means that between the first step, consisting of impregnation and drying, and the second step, comprising the chemical curing of the binder preparation, the composite from the first step is laminated with at least one type of conductive metal.

[0123] In particular, at least one of the following can be considered as conductive metals: copper, stainless steel, gold, aluminum, silver, zinc, tin, lead, and transition metals. The thickness of the conductive layer, its shape, size, or surface texture are not fundamentally restricted. The conductive metal layer preferably has a thickness of 3 to 300 µm, particularly preferably 3 to 250 µm, in particular 3 to 200 µm. The thickness of the two layers of at least one type of conductive metal, if two layers are used, can vary and does not have to be identical. It is particularly preferred that the conductive metal is copper, and if two conductive layers of conductive metal are used, both layers are copper. The conductive metal is preferably used in the form of a foil made of the metal in question.The average roughness Ra of the metal foil used is preferably at most 2 µm, more preferably at most 1 µm, in particular at most 0.7 µm. The lower the surface roughness, the better the suitability of the respective foil for use in high-frequency applications, which are the preferred goal of the present invention. To improve the adhesion between the conductive metal layer and the composite of binder preparation and reinforcing layer, various prior art methods can be used, such as the use of an adhesion-promoting layer, the electroplating of the metal layer on the composite of binder preparation and reinforcing layer, or vapor deposition. The layer of conductive metal can sit directly on the composite of binder preparation and reinforcing layer or be bonded to it by an adhesion-promoting layer.

[0124] If no reinforcement layer is used, a layer of the binder preparation containing the silphenylene polymers of formula (I) is produced by depositing a layer of binder preparation on a carrier, such as a release film or release plate. In principle, any material from which the dried or cured binder preparation can be subsequently removed is suitable for the carrier, such as polytetrafluoroethylene, polyester, and the like. The removability and film-forming properties on the respective carrier material must be determined individually depending on the binder composition. The statements made regarding the process remain equally valid for this reinforcement-free variant.

[0125] Multilayer structures can be created from the reinforced or unreinforced composite materials from the first step and the laminated composite materials from the second step. For example, stacking several lengths of the composite materials from the first step alternately with the laminated laminates from the second step. The uncured composite materials from the first step are then cured in a process that essentially corresponds to the procedure for producing metal-clad laminates. To create thicker layers, several layers of the reinforced or unreinforced composites from the first step can also be stacked one on top of the other in direct succession.

[0126] The silphenylene polymers of formula (I) can be used not only for the production of metal-clad laminates but also in corrosion-protective preparations, in particular for use for the purpose of corrosion protection at high temperatures.

[0127] In addition, the silphenylene polymers of formula (I) and preparations containing them can also be used for corrosion protection of reinforcing steel in reinforced concrete. Corrosion-inhibiting effects in reinforced concrete are achieved both when the silphenylene polymers of formula (I) and preparations containing them are incorporated into the concrete mix before it is molded and cured, and when the silphenylene polymers of formula (I) or preparations containing them are applied to the surface of the concrete after the concrete has cured.

[0128] In addition to the purpose of corrosion protection on metals, the silphenylene polymers of formula (I) can also be used to manipulate other properties of preparations containing the silphenylene polymers according to the invention or of solids or films obtained from preparations containing the silphenylene polymers of formula (I), such as: Control of the electrical conductivity and the electrical resistance Control of the leveling properties of a preparation Control of the gloss of a moist or cured film or an object Increasing the weathering resistance Increasing the chemical resistance Increasing the color stability Reducing the tendency to chalking Reducing or increasing the static and sliding friction on solids or films obtained from preparations containing the polyorganosiloxanes of the formula (I) Stabilizing or destabilizing foam in the preparation containing the silphenylene polymers according to the invention Improving the adhesion of the preparation containing the polyorganosiloxanes of the formula (I) to substrates Control of the filler and pigment wetting and dispersing behavior, Control of the rheological properties of the preparation containing the silphenylene polymers according to the invention, Control of the mechanical properties, such asFlexibility, scratch resistance, elasticity, extensibility, bending ability, tear resistance, rebound behavior, hardness, density, tear resistance, compression set, behavior at different temperatures, expansion coefficient, abrasion resistance as well as other properties such as thermal conductivity, flammability, gas permeability, resistance to water vapor, hot air, chemicals, weathering and radiation, sterilizability, of solids or films available which contain the silphenylene polymers of formula (I) or preparations containing them, control of electrical properties, such asDielectric loss factor, dielectric strength, dielectric constant, tracking resistance, arc resistance, surface resistance, specific breakdown resistance, flexibility, scratch resistance, elasticity, extensibility, bending ability, tear behavior, rebound behavior, hardness, density, tear resistance, compression set, behavior at different temperatures of solids or films obtainable from the preparation containing the silphenylene polymers of formula (I).

[0129] Examples of applications in which the silphenylene polymers of formula (I) can be used to manipulate the properties described above are the production of coating materials and impregnations and coatings and coverings obtained therefrom on substrates such as metal, glass, wood, mineral substrates, synthetic and natural fibers for the production of textiles, carpets, floor coverings or other goods that can be produced from fibers, leather, plastics such as films, and molded parts.The silphenylene polymers of formula (I) can also be used in preparations, with appropriate selection of the preparation components, as additives for the purposes of defoaming, promoting flow, hydrophobizing, hydrophilizing, filler and pigment dispersion, filler and pigment wetting, substrate wetting, promoting surface smoothness, and reducing adhesion and slip resistance on the surface of the cured composition obtainable from the additive-containing preparation. The silphenylene polymers of formula (I) can be incorporated into elastomer compositions in liquid or cured solid form. They can be used for reinforcement or to improve other performance properties, such as controlling transparency, heat resistance, yellowing tendency, or weathering resistance.

[0130] All symbols in the above formulas have their meanings independent of each other. In all formulas, the silicon atom is tetravalent. Examples:

[0131] The following examples serve to further explain the invention. They are to be understood as illustrative, not limiting.

[0132] Unless otherwise stated, all manipulations are carried out at room temperature of 23°C and under normal pressure (1,013 bar).

[0133] Unless otherwise stated, all data describing product properties apply at room temperature of 23°C and under normal pressure (1,013 bar).

[0134] The devices are commercially available laboratory devices, such as those offered for sale by numerous device manufacturers. Ph stands for one phenyl radical = C 6 H 5 - Me stands for one methyl radical = CH 3 -. Me 2 stands for two methyl radicals.

[0135] PPE stands for polyphenylene ether.

[0136] HCl means hydrogen chloride.

[0137] In this text, substances are characterized by data obtained by instrumental analysis. The underlying measurements are either performed according to publicly available standards or determined using specially developed procedures. To ensure the clarity of the presented teaching, the methods used are listed below.

[0138] In all examples, parts and percentages are by weight unless otherwise stated. Viscosity:

[0139] Unless otherwise stated, viscosities are determined by rotational viscometric measurement according to DIN EN ISO 3219. Unless otherwise stated, all viscosity data apply at 25°C and a standard pressure of 1013 mbar. Refractive index:

[0140] The refractive indices are determined in the wavelength range of visible light, unless otherwise stated, at 589 nm at 25°C and normal pressure of 1013 mbar according to the standard DIN 51423. Transmission:

[0141] The transmission is determined by UV-VIS spectroscopy. A suitable instrument is the Analytik Jena Specord 200.

[0142] The measurement parameters used are: Range: 190 - 1100 nm, Step size: 0.2 nm, Integration time: 0.04 s, Measurement mode: Step mode. First, the reference measurement (background) is performed. A quartz plate, attached to a sample holder (dimensions of the quartz plate: HxW approx. 6 x 7 cm, thickness approx. 2.3 mm), is placed in the sample beam path and measured against air.

[0143] Next, the sample is measured. A quartz plate with a sample applied to it (approximately 1 mm thick) is attached to the sample holder. It is placed in the sample beam path and measured against air. Internal comparison with the background spectrum yields the sample's transmission spectrum. Molecular compositions:

[0144] The molecular compositions are determined by nuclear magnetic resonance spectroscopy (for terminology see ASTM E 386: High-resolution nuclear magnetic resonance spectroscopy (NMR): Terms and Symbols), measuring the 1< H nucleus and the 29< Si nucleus. Description 1< H-NMR measurement:

[0145] Solvent: CDCl3, 99.8% Sample concentration: approx. 50 mg / 1 ml CDCl3 in 5 mm NMR tubes

[0146] Measurement without addition of TMS, spectra referencing of residual CHCl3 in CDCl3 to 7.24 ppm Spectrometer: Bruker Avance I 500 or Bruker Avance HD 500 Probe head: 5 mm BBO probe head or SMART probe head (Bruker)

[0147] Measurement parameters: Pulprog = zg30 TD = 64k NS = 64 or 128 (depending on the sensitivity of the probe head) SW = 20.6 ppm AQ = 3.17 s D1 = 5 s SFO1 = 500.13 MHz O1 = 6.175 ppm

[0148] Processing parameters: SI = 32k WDW = EM LB = 0.3 Hz

[0149] Depending on the type of spectrometer used, individual adjustments of the measurement parameters may be necessary. Description 29< Si-NMR measurement:

[0150] Solvent: C6D6 99.8%d / CCl4 1:1 v / v with 1 wt% Cr(acac) 3 as relaxation reagent Sample concentration: approx. 2 g / 1.5 ml solvent in 10 mm NMR tubes Spectrometer: Bruker Avance 300 Probe head: 10 mm 1H / 13C / 15N / 29Si glass-free QNP probe head (Bruker)

[0151] Measurement parameters: Pulprog = zgig60 TD = 64k NS = 1024 (depending on the sensitivity of the probe head) SW = 200 ppm AQ = 2.75 s D1 = 4 s SFO1 = 300.13 MHz O1 = -50 ppm

[0152] Processing parameters: SI = 64k WDW = EM LB = 0.3 Hz

[0153] Depending on the type of spectrometer used, individual adjustments of the measurement parameters may be necessary. Molecular weight distributions:

[0154] Molecular weight distributions are determined as weight-average Mw and number-average Mn using gel permeation chromatography (GPC or size exclusion chromatography (SEC)) with a polystyrene standard and a refractive index detector (RI detector). Unless otherwise stated, THF is used as the eluent and DIN 55672-1 is applied. Polydispersity is the ratio Mw / Mn. Glass transition temperatures:

[0155] The glass transition temperature is determined by differential scanning calorimetry (DSC) according to DIN 53765, perforated crucible, heating rate 10 K / min. Determination of particle size:

[0156] Particle sizes were measured using the dynamic light scattering (DLS) method, determining the zeta potential. The following tools and reagents were used for the determination: 10 x 10 x 45 mm polystyrene cuvettes, disposable Pasteur pipettes, and ultrapure water.

[0157] The sample to be measured is homogenized and filled into the measuring cuvette without any bubbles.

[0158] The measurement is carried out at 25°C after an equilibration time of 300s with high resolution and automatic measurement time setting.

[0159] The specified values always refer to the value D(50). D(50) is defined as the volume-averaged particle diameter where 50% of all measured particles have a volume-averaged diameter smaller than the stated value D(50). Determination of dielectric properties: Df, Dk

[0160] The dielectric properties are determined according to IPC TM 650 2.5.5.13 using a Keysight / Agilent E8361A network analyzer using the split-cylinder resonator method at 10 GHz. Performing the microscopy:

[0161] The micro- / nanostructure was characterized by light microscopy and transmission electron microscopy.

[0162] Light microscopy: Sample preparation: 1 drop of sample (undiluted) on a slide; covered with a coverslip. Instrument: LEICA DMRXA2 with CCD camera LEICA DFC420 (2592x1944 pixels). Image: Transmitted light - interference contrast, various magnification levels.

[0163] Transmission electron microscopy: Sample preparation: 1 drop of sample (dilution 1:20, adjustment necessary if necessary) on a coated TEM grid; addition of a contrast agent if required; drying at room temperature. Device: ZEISS LIBRA 120 with Sharp Eye CCD camera (1024x1024 pixels). Image: Excitation voltage 120 kV; TEM brightfield; various magnification levels. Adhesion test by peel strength test:

[0164] The adhesion of the metal layers laminated to the composite layers with or without reinforcement material was determined according to the method IPC-TM 650 2.4.8 "Peel Strength of Metallic Clad Laminates" in the "as received" version, ie without thermal stress or exposure.

[0165] A 35 µm copper foil, mass 285 ± 10 g / m 2< , surface roughness Rz ≤ 8 µm, mean roughness Ra ≤ 0.4 µm was laminated on both sides to a composite layer of 100 µm thickness, with 200°C, 2.0 MPa, 30 mm Hg column acting for 180 min for curing and lamination. Flammability test:

[0166] The test was conducted as a vertical fire test according to the specifications of UL 94-V from Underwriters Laboratories. The test specimens were conditioned prior to testing under the following conditions: 2 days of storage at 23°C and 50% relative humidity, followed by 7 days at 70°C in a warm-air oven. The flame application was carried out using a Tirill burner flame. The flame application time was 2 x 10 s each. The second flame application time began as soon as the ignited specimen had extinguished. For non-ignited specimens, the second flame application took place immediately after the first. The test specimen was 5" (127 mm) long and 0.5" (12.7 mm) wide. The panels to be tested were 0.4" (10.2 mm) thick. The panels were secured vertically at a length of 1 / 4" at the top. A mesh coated with surgical cotton was placed 12" (305 mm) below the test plate. The burner was adjusted to produce a blue flame 3 / 4" long.The flame is directed from a distance of 3 / 8" (9.5 mm) onto the bottom edge of the plastic sheet. After 10 seconds, the flame is removed. The ignition time of the test piece is recorded. As soon as the flame ceases, the burner flame is placed under the test piece again for 10 seconds. After removing the flame, the ignition time and the glow time of the piece are recorded. The test is carried out on five different test pieces. Synthesis example 1: Preparation of a silphenylene polymer from chlorosilanes by the process according to the invention:

[0167] 48 g of magnesium turnings (2 mol) are placed into a 2-liter three-necked glass flask equipped with a spherical condenser and dropping funnel. The apparatus is then evacuated to an internal pressure of 10 -3 < mbar, and the glass walls are simultaneously heated to 270°C with a hot-air dryer to remove any remaining water adhering to the magnesium and the glass walls. The vacuum is then broken with argon until a pressure of 1013 mbar is reached inside the apparatus. The apparatus is allowed to cool to room temperature of 23°C.

[0168] 250 ml of dried, nitrogen-purged 1,4-dioxane are charged into the apparatus. A grain of iodine, weighing approximately 50 mg, is added, and the mixture is heated to an internal temperature of 60°C. 118 g (0.5 mol) of 1,4-dibromobenzene are dissolved in 400 ml of dried, nitrogen-purged 1,4-dioxane under a dry nitrogen atmosphere, and the mixture is transferred to the dropping funnel. The mixture is added evenly over a period of 3 h, while simultaneously counterheating against the exothermic reaction so that the internal temperature does not exceed 65°C. The mixture is then stirred at 65°C for 7 h to complete the reaction to form the 1,4-dibromobenzene Grignard reagent. A gray, cloudy preparation is obtained.

[0169] The reaction mixture is cooled to 2°C. A mixture of 89.8 g of a mixture of 0.14 mol of vinyldimethylchlorosilane and 0.57 mol of dimethyldichlorosilane is added to the dropping funnel. This step is also carried out under dry nitrogen as a protective gas. The silane mixture is added evenly over a period of 3 hours, with cooling again to keep the temperature below 5°C. After addition, the mixture is stirred for a further 3 hours at 2°C. The reaction mixture is then filtered through a filter plate with a pore size of 1.2 µm. The filtrate is clear and of low viscosity. The 1,4-dioxane is then evaporated at 120°C and a vacuum of 20 mbar. A slightly reddish-yellow solid is obtained, which is then dissolved in toluene to form a 50% solution for further workup.While stirring, 200 ml of deionized water is added to the toluene solution, the stirrer is turned off, and the mixture is allowed to settle, during which the aqueous and organic phases separate. The aqueous phase is drained, and the washing process is repeated three more times in the same manner. 30 g of sodium sulfate is added to the remaining organic phase, stirred for 5 minutes, and then filtered through a 1.2 µm filter plate. The toluene is then completely distilled off at 120°C and a vacuum of 20 mbar, yielding an orange solid.

[0170] SEC: Mw = 1050 g / mol, Mn = 713 g / mol, polydispersity PD = 1.47.

[0171] Silanol and alkoxy groups are not detectable in 1< H-NMR.

[0172] According to 29< Si-NMR, the molar composition of the silicon-containing portion of the preparation is: (CH 2 =CH)Me 2 Si(C 6 H 4 )-: 21.8% - (C 6 H 4 )(Me 2 )Si(C 6 H 4 )-: 78.2%

[0173] Each bridging -(C 6 H 4 )- residue is counted as half of each Si atom bonded to it.

[0174] This product is readily soluble in toluene. An 80% toluene solution, consisting of 80% of the reaction product in 20% toluene, can be easily prepared. The percentages refer to the mass. However, in the application examples, a 50% toluene solution is used because the counterexamples exhibit lower solubility, thus ensuring comparability. The 50% preparation is referred to below as 1.1. The silphenylene polymer prepared here is not accessible according to EP 0913420 because it cannot be prepared by hydrosilylation. Synthesis example 2: Preparation of a silphenylene polymer from alkoxysilanes by the process according to the invention:

[0175] The procedure is the same as that described in Synthesis Example 1, with the following differences: Instead of 1,4-dioxane, THF is used as the solvent. Instead of a mixture of chlorosilanes, 84.6 g of a mixture of 0.14 mol of vinyldimethylmethoxysilane (116 g / mol) and 0.57 mol of dimethyldimethoxysilane (120 g / mol) is used.

[0176] No silanol groups are detectable in the resulting product by 1< H NMR. Methoxy groups are present in an amount of approximately 0.1 weight percent according to 1< H NMR.

[0177] The following molecular weights were determined by SEC (eluent toluene): Mw = 1134 g / mol, Mn = 803 g / mol, polydispersity PD = 1.41.

[0178] According to 29< Si-NMR, the molar composition of the silicon-containing portion of the preparation is: (CH 2 =CH)Me 2 Si(C 6 H 4 )-: 22.1% -(C 6 H 4 )(Me 2 )Si(C 6 H 4 )-: 77.9%

[0179] Each bridging -(C 6 H 4 )- residue is counted as half of each Si atom bonded to it.

[0180] This product is readily soluble in toluene. An 80% toluene solution, consisting of 80% of the reaction product in 20% toluene, can be easily prepared. The percentages refer to the mass. However, in the application examples, a 50% toluene solution is used because the counterexamples exhibit lower solubility, thus ensuring comparability. The 50% preparation is referred to below as 2.1.

[0181] The silphenylene polymer prepared here is not accessible according to EP 0913420 because it cannot be prepared by hydrosilylation. Synthesis example 3: Preparation of a silphenylene polymer according to the invention from alkoxysilanes using a multihalogenated organic raw material:

[0182] The procedure is the same as that described in Synthesis Example 1 with the following differences: Instead of 1,4-dioxane, THF is used as the solvent. Instead of a mixture of chlorosilanes, 67.8 g of a mixture of 0.14 mol of vinyldimethylmethoxysilane (116 g / mol) and 0.43 mol of dimethyldimethoxysilane (120 g / mol) is used. Instead of 1,4-dibromobenzene, 0.25 mol (118 g) of 3,3',5,5'-tetrabromo-1,1'-biphenyl is used.

[0183] No silanol groups are detectable in the resulting product by 1< H NMR. Methoxy groups are present in an amount of < 0.1 weight percent according to 1< H NMR.

[0184] The following molecular weights were determined by SEC (eluent toluene): Mw = 1347 g / mol, Mn = 941 g / mol, polydispersity PD = 1.43.

[0185] According to 29< Si-NMR, the molar composition of the silicon-containing portion of the preparation is: (CH 2 =CH)Me 2 Si(C 12 H 8 )-: 21.3% -(C 12 H 8 )(Me 2 )Si(C 12 H 8 )-: 78.7%

[0186] Each bridging -(C 12 H 8 )- residue is counted as one quarter of each Si atom bonded to it.

[0187] This product is readily soluble in toluene. An 80% toluene solution, consisting of 80% of the reaction product in 20% toluene, can be easily prepared. The percentages refer to the mass. However, in the application examples, a 50% toluene solution is used because the counterexamples exhibit lower solubility, thus ensuring comparability. The 50% preparation is referred to below as 3.1.

[0188] The silphenylene polymer prepared here is not accessible according to EP 0913420 because it cannot be prepared by hydrosilylation. Synthesis example 4: Preparation of a silphenylene-silalkylene copolymer according to the prior art according to Example 1 in EP 0913420 as a comparative example not according to the invention.

[0189] The starting materials 1,4-bis(phenylmethylvinylsilyl)phenylene and 1,4-bis(dimethylsilyl)phenylene were prepared by Grignard synthesis. The same procedure as described in Synthesis Example 1 is suitable for this purpose. In the case of 1,4-bis(phenylmethylvinylsilyl)phenylene, a di-Gringnard reagent was generated in THF in the first step from four times the molar amount of magnesium turnings based on the amount of 1,4-dibromobenzene used and the 1,4-dibromobenzene. In the second step, this di-Gringnard reagent was reacted with twice the molar amount of phenylmethylvinylmethoxysilane based on the dibromobenzene, as described in Example 1. The desired 1,4-bis(phenylmethylvinylsilyl)phenylene was obtained, the identity of which was confirmed analytically by 1< H and 29< Si NMR spectroscopy.The same procedure was used to prepare 1,4-bis(dimethylsilyl)phenylene, using the corresponding amount of dimethylmethoxysilane instead of phenylmethylvinylmethoxysilane. Here, too, the desired chemical component can be confirmed by NMR spectroscopy. At this point, a very significant difference between this prior art and the invention presented here becomes apparent, because the effort required to prepare the experiment according to Example 1 of EP 0913420 alone is already twice as high as the effort required to prepare a silphenylene polymer according to the invention. The further experimental procedure corresponds in all details to the description according to Example 1 in EP 0913420. The result is a solid as the reaction product, which, according to SEC, has a weight-average molecular weight of Mw = 19900 g / mol. EP 0913420 does not provide any information on Mn and PD, so no comparison is possible here.In the present case, the following values were obtained: Mn = 3042 g / mol and PD = 6.54. The expected signals for the building blocks were found in both 1< H NMR and 29< Si NMR, so the product obtained here is undoubtedly chemically identical to the product according to Example 1 in EP 0913420. The resulting product is soluble in toluene and xylene at a concentration of up to 50%. Since, in contrast to the silphenyl polymers of the invention, no higher solubility is achieved, this material is used for property comparison at a concentration of 50% in toluene.

[0190] This 50% preparation in toluene is referred to below as 4.1. Synthesis example 5: Preparation of a silphenylene-polysiloxane copolymer according to the prior art according to US 6072016 Example 1 as a non-inventive comparative example:

[0191] For Example 1 according to US 6072016, according to Reference Example 1 of US 6072016, a starting polymer of 1,4-bis(phenylmethylvinylsilyl)phenylene and 1,4-bis(dimethylsilyl)phenylene, the same starting materials as already described in Synthesis Example 4, and additionally vinyltrimethoxysilane, is required. The preparation of 1,4-bis(phenylmethylvinylsilyl)phenylene and 1,4-bis(dimethylsilyl)phenylene has already been described in Synthesis Example 4. To obtain the starting polymer for Example 1 according to US 6072016, it was prepared according to the description of Reference Example 1 of US 6072016. The relative amounts of 1,4-bis(phenylmethylvinylsilyl)phenylene to 1,4-bis(dimethylsilyl)phenylene are different here from Synthesis Example 4, or Example 1 according to EP 0913420. Therefore, the vinyltrimethoxysilane is terminally hydrosilylated to the remaining Si-H of the 1,4-bis(dimethylsilyl)phenylene used in excess.In this case, too, the chemical identity of the resulting product can be clarified by NMR and SEC analysis, ensuring that the resulting product is the same as that described in Reference Example 1 of US 6072016. The weight-average molecular weight determined by SEC for the product in the experiment reproduced here is Mw = 9675 g / mol. US 6072016 makes no disclosures regarding the number-average molecular weight Mn and the polydispersity index PD. In the present case, they were determined to be Mn = 6365 g / mol and PD = 1.52.

[0192] To remain strictly within the prior art of US 6072016, the curing of the resulting bistrimethoxysilyl-terminated silphenylene was carried out according to the procedure described in Example 1 of US 6072016, i.e., the curing was carried out using methyltri(methylethylketoxime)silane in toluene. For this purpose, a 50% toluene solution of the bistrimethoxysilyl-terminated silphenylene according to Reference Example 1 of US 6072016 was prepared as described in Example 1 of US 6072016. This 50% toluene solution of toluene and the bistrimethoxysilyl-terminated silphenylene according to Reference Example 1 of US 6072016 is referred to below as 5.1. Application example 1: Use of the silphenylene polymers 1.1, 2.1 and 3.1 according to the invention and the non-inventive counterexamples 4.1 and 5.1 for the production of copper-clad laminates:

[0193] The inventive silphenylene polymers 1.1, 2.1, and 3.1 prepared according to Synthesis Examples 1 to 5, the non-inventive silphenylene silalkylene copolymer 4.1, and the alkoxysilyl-terminated silphenylene silalkylene copolymer 5.1, also non-inventive, were used as binders to produce copper-clad laminates with a glass fiber-reinforced composite layer. The following starting materials were used:

[0194] Copper foil: 35 µm thick copper foil (285 ± 10 g / m 2< ) from Jiangtong-yates Copper Foil Co Ltd, with a surface roughness of Rz ≤ 8 µm and a centerline roughness of Ra ≤ 0.4 µm, purity ≥ 99.8%.

[0195] Glass fiber: E-glass fiber type 1080 E manufactured by Changzhou Xingao Insulation Materials Co. Ltd. Thickness 0.055 ± 0.012 mm, 47.5 ± 2.5 g / m 2< .

[0196] To ensure comparability of the binders, all binders in this example were used as 50% solutions in toluene.

[0197] To initiate curing, the vinyl-functional inventive silphenylene polymers 1.1, 2.1, and 3.1 and the non-inventive silphenylene silalkylene copolymer 4.1 were each mixed with 1 weight percent of dicumyl peroxide, based on the amount of silphenylene polymer 1.1, 2.1, and 3.1, or silphenylene silalkylene copolymer 4.1, used. The mixture was evenly distributed in the resin matrix by stirring. 5.1 was cured by adding methyltri(methylethylketoxime)silane in an amount as specified in Example 1 according to US Pat. No. 6,072,016.

[0198] Laminates were produced by impregnating 30 x 30 cm glass fiber layers layer by layer with the respective organopolysiloxane, optionally as a toluene solution, using a deaerator roller to ensure that no bubbles were formed. The glass fiber layers were placed on a dimensionally stable, flat stainless steel base, onto which a layer of copper foil was applied before the first layer of glass fiber was applied. A total of three layers of glass fiber fabric were impregnated one after the other. To remove any solvent, the impregnated fabrics were dried to constant weight at 60°C in a vacuum drying oven at 10 mbar. A second layer of copper foil was then applied on top of the impregnated glass fiber layer, and another dimensionally stable stainless steel plate was placed on top. The laminate was baked in a heatable press at 2 MPa pressure, for 120 minutes at 200°C and 30 mbar vacuum.Copper-clad laminates with a total thickness of 260 ± 20 µm are obtained.

[0199] The dielectric properties were determined according to IPC TM 650 2.5.5.13 using a Keysight / Agilent E8361A network analyzer using the split-cylinder resonator method at 10 GHz. The following values were obtained: Test substance D k D f 1.1 (according to the invention) 3,08 0,0019 2.1 (according to the invention) 3,10 0,0020 3.1 (according to the invention) 3,10 0,0018 4.1 (not according to the invention) 3,37 0,0033 5.1 (not according to the invention) 3,73 0,0045

[0200] The D f and D k values of the copper-clad laminates made from the silphenylene polymers according to the invention and the silphenylene silalkylene copolymer are significantly lower than the D f and D k values obtained with the ketoxime-cured silphenylene silalkylene copolymer according to US 6072016, which has a significant organopolysiloxane content due to the ketoxime silane used and thus a higher polarity. Since the lowest possible dielectric loss factors and dielectric constants are aimed for for high-frequency applications, this is not desired, and the silphenylene polymers according to the invention represent an improvement over this prior art with regard to their dielectric properties. The non-inventive silphenylene silalkylene polymers are more similar to the silphenylene polymers according to the invention in terms of their dielectric properties, but are not equivalent.Although they are comparable to the silphenylene polymers according to the invention in terms of the degree to which polar siloxane bonds are avoided, platinum residues remain in the non-inventive silphenylene silalkylene copolymers due to the chosen method of preparation by hydrosilylation, which negatively impacts the dielectric properties and leads to an increase in the dielectric loss factor. Thus, while the chemical composition of the silphenylene silalkylene copolymers alone is fundamentally suitable for achieving the dielectric properties according to the invention, this can only be achieved if the platinum residues can be successfully removed. This causes additional effort and thus reduces the economic viability of this technology compared to the silphenylene polymers according to the invention.In addition, it was already pointed out in the fourth synthesis example that the starting materials for the hydrosilylation can only be obtained by two upstream Grignard syntheses, which multiplies the overall effort compared to the technology according to the invention, makes it uneconomical and is no longer feasible on the market. Application example 2: Use of the silphenylene polymers 1.1, 2.1 and 3.1 according to the invention and the non-inventive counterexamples 4.1 and 5.1 for the production of metal-clad laminates via prepregs:

[0201] The inventive silphenylene polymers 1.1, 2.1 and 3.1 prepared according to Synthesis Examples 1 to 5 and the non-inventive silphenylene silalkylene copolymer 4.1 and the likewise non-inventive alkoxysilyl-terminated silphenylene silalkylene copolymer 5.1 were used as binders to produce copper-clad laminates with a glass fiber reinforced composite layer. Instead of directly constructing the laminate without a prepreg intermediate, as in Application Example 1, prepregs were produced this time by impregnating the glass fiber layers as individual layers, each on a polytetrafluoroethylene film, with the resin preparation and then drying them to constant weight in a vacuum drying cabinet. Three layers of impregnated glass fiber fabric produced in this way were then stacked on top of each other on a copper foil, and the stack was sealed with a layer of copper foil. This multilayer structure was pressed and cured between two dimensionally stable stainless steel plates in a vacuum press under the conditions specified in Example 1, analogously to Application Example 1.

[0202] The obtained laminates had thicknesses of 290 ± 20 µm.

[0203] The following dielectric properties were measured on the obtained laminates: Test substance D k D f 1.1 (according to the invention) 3,10 0,0020 2.1 (according to the invention) 3,09 0,0019 3.1 (according to the invention) 3,11 0,0019 4.1 (not according to the invention) 3,40 0,0035 5.1 (not according to the invention) 3,87 0,0048

[0204] The D f and D k values of the copper-clad laminates made from the silphenylene polymers according to the invention and the silphenylene silalkylene copolymer are significantly lower than the D f and D k values cured with the ketoxime-cured silphenylene silalkylene copolymer according to US 6072016, which has a significant organopolysiloxane content due to the ketoxime silane used and thus a higher polarity. Since the lowest possible dielectric loss factors and dielectric constants are aimed for for high-frequency applications, this is not desired and the silphenylene polymers according to the invention represent an improvement over this prior art with regard to their dielectric properties. The non-inventive silphenylene silalkylene polymers are more similar to the silphenylene polymers according to the invention in terms of their dielectric properties, but are not equivalent.Although they are comparable to the silphenylene polymers of the invention in terms of the degree to which polar siloxane bonds are avoided, platinum residues remain in the non-inventive silphenylene silalkylene copolymers due to the chosen method of preparation by hydrosilylation. These residues have a negative impact on the dielectric properties and lead to an increase in the dielectric loss factor. Thus, while the chemical composition of the silphenylene silalkylene copolymers alone is fundamentally suitable for achieving the dielectric properties of the invention, this can only be achieved if the platinum residues can be successfully removed. This requires additional effort and thus reduces the economic viability of this technology compared to the silphenylene polymers of the invention.In addition, it was already pointed out in the fourth synthesis example that the starting materials for the hydrosilylation can only be obtained by two upstream Grignard syntheses, which multiplies the overall effort compared to the technology according to the invention, makes it uneconomical and is no longer feasible on the market. Application example 3: Use of the silphenylene polymers 1.1, 2.1 and 3.1 according to the invention and the non-inventive counterexamples 4.1 and 5.1 in a mixture with organic polymers for the production of metal-clad laminates:

[0205] The procedure essentially corresponds to that described in application example 2, except that this time organic polymers with the silphenylene polymers 1.1, 2.1 and 3.1 according to the invention prepared in synthesis examples 1 to 5 and the non-inventive silphenylene silalkylene copolymer 4.1 and the alkoxysilyl-terminated silphenylene silalkylene copolymer 5.1, also not according to the invention, are used in a mixture as binders to produce copper-clad laminates with a glass fiber reinforced composite layer.

[0206] The final solvent-free mixtures always contained 30 weight percent of components 1.1, 2.1, 3.1, 4.1, and 5.1, each mixed with 70 weight percent organic polymer. The organic polymers used were triallyl isocyanurate, NORYL SA 9000, an alpha-omega methacrylate-terminated polyphenylene ether supplied by SABIC, Mn = 2500 g / mol, Tg = 160°C, and B 3000 from Nippon Soda, a liquid polybutadiene with an Mn = 3200 and a viscosity at 45°C of 210 poise and more than 85% 1,2-vinyl structure in the polymer chain.

[0207] The polymers were always used in the same ratio. They were dissolved or dispersed in xylene, with 30 parts by weight of SA 9000, 25 parts by weight of B 3000, and 15 parts by weight of triallyl isocyanurate being dispersed with 100 parts by weight of xylene.

[0208] The resulting preparation was mixed with the toluene solutions of components 1.1, 2.1, 3.1, 4.1, and 5.1 according to Application Example 2 such that the specified mixing ratio of 30% of 1.1, 2.1, 3.1, 4.1, and 5.1, respectively, and 70% of organic components was present in the resulting solution. These solutions were then used to produce copper-clad laminates over prepregs as described in Application Example 2.

[0209] The obtained laminates had thicknesses of 290 ± 20 µm.

[0210] The following dielectric properties were measured on the obtained laminates: Test substance D k D f 1.1 (according to the invention) 3,01 0,0019 2.1 (according to the invention) 3,00 0,0018 3.1 (according to the invention) 3,00 0,0018 4.1 (not according to the invention) 3,39 0,0034 5.1 (not according to the invention) 3, 67 0,0041

[0211] The D k and D f values achieved for the copper-clad laminates using the inventive silphenylene polymers 1.1, 2.1, and 3.1 are significantly lower than the D f and D k values achieved with the non-inventive silphenylene silalkylene copolymer 4.1 and the also non-inventive alkoxysilyl-terminated silphenylene silalkylene copolymer 5.1. Since the lowest possible dielectric loss factors and dielectric constants are desired for high-frequency applications, the inventive effect is clearly evident. Application example 4:

[0212] Conducting a fire test according to UL 94 V: The test was conducted as a vertical fire test according to the specifications of UL 94-V by Underwriters Laboratories. The test specimens made of the inventive silphenylene polymers 1.1, 2.1, and 3.1 and the non-inventive silphenylene silalkylene copolymer 4.1 were obtained from toluene solutions into which 2% dicumyl peroxide was mixed for curing. The percentage is by weight and refers to the amount of dissolved product as 100%. The total 50% solution thus contains 1% by weight of dicumyl peroxide. The solutions were each poured into a suitable container, and the solvent was then gradually evaporated in a convection oven, first for 4 hours at 80°C and then for 2 hours at 120°C. The resulting evaporation residues were then cured at 200°C for 2 hours.The procedure for curing the non-inventive alkoxysilyl-terminated silphenylene silalkylene copolymer 5.1 was carried out by adding the previously described ketoximosilane as described in Example 1 in US 6072016. Otherwise, the procedure for producing the sample body corresponds to the procedure described for the test specimens from 1.1, 2.1, 3.1, and 4.1.

[0213] The resulting specimens were conditioned under the following conditions prior to testing: 2 days of storage at 23°C and 50% relative humidity, followed by 7 days at 70°C in a hot-air oven. The flame application was carried out using a Tirill burner flame. The flame application time was 2 x 10 s each. The second flame application began as soon as the ignited specimen had extinguished. For non-ignited specimens, the second flame application took place immediately after the first. The test piece was 5" (127 mm) long and 0.5" (12.7 mm) wide. The panels to be tested were 0.4" (10.2 mm) thick. The panels were secured vertically at a length of 1 / 4" at the top. A mesh coated with surgical cotton was placed 12" (305 mm) below the test panel. The burner was adjusted to produce a blue flame 3 / 4" long. The flame is directed at the bottom edge of the plastic plate from a distance of 3 / 8" (9.5 mm).After 10 seconds of exposure, the flame is removed. The ignition time of the test piece is recorded. As soon as the flame ceases, the burner flame is placed under the test piece again for 10 seconds. After removing the flame, the ignition time and the glow duration of the piece are recorded. The test is carried out on five different test pieces.

[0214] The following results were obtained: Test criterion 1.1 2.1 3.1 4.1* 5.1* Afterburning time after flame application 3s 5s 4s 25s 16s Afterburning and afterglow of the sample after second flame application 16s 11s 14s 53s 32s Burning dripping (ignition of the cotton wool) No No No Yes No Complete burning of the sample No No No No No Flammability class V-0 V-0 V-0 V-2 V-1 * not according to the invention

[0215] Flammability class V-0 is the highest flammability class according to UL94-V. V-0 is the requirement for the target application of copper-clad laminates for high-frequency applications. Only the silphenylene polymers according to the invention meet this requirement. Overall, both the synthesis examples and the application examples demonstrate that the desired effect of the invention is achieved and that the present invention improves the existing state of the art in the required manner.

Claims

1. Silphenylene polymers of the formula (I)         RaR1bSi[Y[(SiR2cR3d)e]f]gYSiRaR1b     (I), where R may be identical or different radicals and are a hydrogen radical or an olefinically or acetylenically unsaturated, aliphatic or cycloaliphatic hydrocarbon radical, R2 independently of one another are identical or different radicals, where R2 may be a hydrogen radical or a saturated or olefinically or acetylenically unsaturated, Si-C-bonded C1 - C18 hydrocarbon radical which may be substituted by heteroatoms, where the two or more oxygen atoms in the same radical R2 are always separated from one another by hydrocarbon units and where oxygen atoms and silicon atoms are not joined to one another to form Si-O units if both kinds of heteroatom are present simultaneously in one radical R2, but instead are always separated from one another by hydrocarbon units, whereas two or more Si atoms in the same radical R2 may be joined to one another by direct Si-Si bonds and the Si atoms are always tetravalent and the remaining valences of the Si atoms are saturated by further Si-C-bonded substituents, it being possible for these to be olefinically or acetylenically unsaturated, and R2 may also comprise olefinically or acetylenically unsaturated functional groups, which may likewise contain heteroatoms, where R2 may also be a hydroxyl radical or a monovalent aliphatic, cycloaliphatic or aromatic, SiC-bonded, organic hydrocarbon radical which is bonded to the silicon atom through an oxygen atom, is unsubstituted or substituted by heteroatoms and has 1 to 18 carbon atoms, R1 and R3 independently of one another may be identical or different radicals and are either a hydrocarbon radical or a monovalent aliphatic, cycloaliphatic or aromatic, Si-C-bonded, organic hydrocarbon radical which is unsubstituted or substituted by heteroatoms and has 1 to 18 carbon atoms, and which may also be an unsaturated hydrocarbon radical, where R1 and R3 may also be a hydroxyl radical or a monovalent aliphatic, cycloaliphatic or aromatic, Si-C-bonded, organic hydrocarbon radical which is bonded to the silicon atom through an oxygen atom, is unsubstituted or substituted by heteroatoms and has 1 to 18 carbon atoms, Y is a chemical bond or a di- to dodecavalent aromatic, alkylaromatic or cycloalkylaromatic or a di-to dodecavalent aliphatic or cycloaliphatic radical having 1 to 48 carbon atoms and a main chain of which is free from heteroatoms, where the radical Y, if it is not a chemical bond, is always bonded by Si-C linkage to the silicon atoms that it bridges, a is a number with a value of 1 or 2, b is a number with a value of 1 or 2, where the sum a + b = 3, c is a number with a value of 0, 1 or 2, d is a number with a value of 0, 1 or 2, where the sum c + d = 2, e is a number from 1 to 12, f is a number with a value of 1 to 12, and g is a number with a value of 3 to 250, with the provisos that at least one olefinically or acetylenically unsaturated radical R, R1, R2 or R3 must be present per silphenylene polymer of the formula (I), the sum of all organic radicals bonded to Si atoms through an oxygen atom, based on the sum of all Si-bonded radicals R, R1, R2 and R3 as 100 mol%, must not be more than 10 mol%, and based on all bridging radicals Y as 100 mol%, at least 55 mol% of radicals Y are a di- to dodecavalent aromatic, alkylaromatic and cycloalkylaromatic radical.

2. Silphenylene polymers according to Claim 1, wherein the heteroatoms in R2 are selected from oxygen atoms and silicon atoms.

3. Silphenylene polymers according to either of the preceding claims, wherein the olefinically or acetylenically unsaturated radicals R, R1, R2 or R3 are selected from alkenyl radicals, acryloyloxy and methacryloyloxy radicals of acrylic acid or methacrylic acid, and acrylic esters or methacrylic esters of unbranched or branched alcohols having 1 to 15 carbon atoms.

4. Silphenylene polymers according to any of the preceding claims, wherein Y is a bridging aromatic unit having 1 to 24 carbon atoms between two to twelve carbosilyl units.

5. Silphenylene polymers according to any of the preceding claims, wherein the bridging aromatic radicals Y are of the formula (IVa), (IVb) and (IVc) where the radicals R10, R11, R12 and R13 may be a hydrogen radical or a substituted or unsubstituted hydrocarbon radical or a group of the formula OR14, where R14 is a hydrocarbon radical, and where adjacent radicals in formula (IVa), (IVb) and (IVc) may be coupled to one another to form cyclic radicals, to produce fused ring systems.

6. Silphenylene polymers according to any of the preceding claims, wherein the sum of all organic radicals bonded to Si atoms by an oxygen atom, based on the sum of all Si-bonded radicals R, R1, R2 and R3 as 100 mol%, is not more than 1 mol%.

7. Silphenylene polymers according to any of the preceding claims, which in the noncrosslinked state are liquid and at 25°C possess viscosities of 20 to 8 000 000 mPas, determined by rotational viscometry according to DIN EN ISO 3219 or are solid and possess glass transition temperatures in the range from 25°C to 250°C, determined by differential scanning calorimetry (DSC) according to DIN 53765, perforated crucible, heating rate 10 K / min.

8. Silphenylene polymers according to any of the preceding claims, wherein g is a number with a value of at least 5.

9. Process for preparing silphenylene polymers of the formula (I) according to any of the preceding claims RaR1bSi[Y[(SiR2cR3d)e]f]gYSiRaR1b (I), wherein compounds of the formula (VIII)         [Hal]o-Y     (VIII), where Hal is a Cl, Br or iodine atom, o is a number from 2 to 12, and Y has the definitions indicated for it in Claim 1 to 8, are reacted with magnesium and with silicon-containing compounds which are selected from compounds of the formulae (IV), (V) and (VI),         R15hR16iSi     (IV),         R15jR16kSi[SiRl17Rm18]nSiRj15Rk16     (V),         R15jR16kSi[SiRl17Rm18]n-X1-[SiRl17Rm18]SiR15jR16k     (VI), where R15 is a halogen atom or a C1 - C3 alkoxy group, R16, R17 and R18 independently of one another are radicals of the group of the radicals R, R1, R2 or R3, but not a radical of the formula (II), and R18 may additionally be a halogen radical or a C1 - C3 alkoxy radical, which contain no functional groups comprising carbonyl or carboxyl groups, hydroxyl groups, doubly bonded nitrogen atoms, primary, secondary or tertiary amine groups or thiol groups, X1 is a chemical bond or a divalent bridging aliphatic, cycloalkylaliphatic, cycloalkylaromatic or an alkylaromatic hydrocarbon radical which contains no functional groups comprising carbonyl or carboxyl groups, hydroxyl groups, doubly bonded nitrogen atoms, primary, secondary or tertiary amine groups or thiol groups and produced by hydrosilylation of a hydrosilylatable, olefinically or acetylenically unsaturated precursor Z of the formula R19-X2-R19 in which R19 is an olefinically or acetylenically unsaturated, hydrosilylatable C2 - C8 radical and X2 is the radical X1 shortened on either side by the C2 - C8, h is an integer with a value of 1, 2, 3 or 4, i is an integer with a value of 0, 1, 2 or 3 and the sum h + i = 4, j is a number with a value of 0, 1, 2 or 3, where j possesses a value of 1 at least at one terminal Si atom of the di-, oligo- or polysilane of the formula (V), so that there is always at least one radical R15 per molecule of the formula (V), k is an integer with a value of 0, 1, 2 or 3, where k + j = 3, l and m are each a number with a value of 0, 1 or 2, where l + m = 2, n is a number with a value of 0 to 50, and compounds of the formula (VIII)         [Hal]o-Y     (VIII), where Hal is a Cl, Br or iodine atom, o is a number from 2 to 12, and Y has the definitions indicated for it in Claim 1 to 7.

10. Process according to Claim 9, wherein the compound of the formula (VIII) is selected from 1,4-dibromobenzene, 1,4-dichlorobenzene, 1,2-dichloroethane and 1,2-dibromoethane.

11. Process according to Claim 9 or 10, wherein the process is carried out in ether.

12. Process according to Claim 9 to 11, wherein the process is performed in stages, by first reacting the component of the formula (VIII) with magnesium and in the second step adding the respectively required selection of components (IV), (V), (VI) and (VII).

13. Use of the copolymers according to any of Claims 1 to 8 in the production of coating materials and impregnation systems and resultant coatings and coverings on substrates, as binders or as additives in preparations.

14. Use of the copolymers according to any of Claims 1 to 8 for producing metal-faced laminates.

15. Use according to Claim 14, wherein the metal is selected from copper, stainless steel, gold, aluminium, silver, zinc, tin, lead and transition metals.