Phenol-terminated siloxanes

Abstract

The invention relates to phenol-terminated siloxanes, processes for the production thereof, and the use of the phenol-terminated siloxanes as a modifier (= siloxane-based modifier) in organic resins.

Description

[0001] Phenol-terminated siloxanes

[0002] The invention relates to phenol-terminated siloxanes, processes for their preparation and the use of the phenol-terminated siloxanes as modifiers (= siloxane-based modifiers) in organic resins.

[0003] Organomodified siloxanes have a wide range of applications. As important additives for plastics, they impart important properties such as hydrophobicity and protection against water absorption. For siloxanes to be used in this way, however, their compatibility with the plastic to be modified is crucial. Good compatibility is achieved, for example, when the siloxanes form a homogeneous bond with the plastics, thus showing no phase separation. Phase separation would become noticeable through the leaching of the modifier from the plastic.

[0004] Examples of the plastics to be modified are epoxy (EP) resins or epoxy resin systems. These are used in a wide variety of applications and have established themselves as one of the most widely used thermoset classes in composite materials, for example, in combination with glass, carbon (CFRP), or aramid fibers. In addition, organic high-performance reactive resins, such as cyanate ester (CE), bismaleimide (BMI), polyimide (PI), benzoxazine, or phthalonitrile resins, or reactive resin mixtures, such as bis(benzocyclobutenimide) / bismaleimide, cyanate ester / epoxy, or bismaleimide / cyanate ester (BT resins), have gained increasing importance in recent years as matrix resins in fiber composites in industry, automotive engineering, and aerospace.Compared to epoxy resins, for example, CE-, BMI- or PI-based polymer matrix resins combine high mechanical strength with high glass transition temperatures, high thermal resilience and long-term stability, which greatly expands the application possibilities of these thermosets, especially in the high-temperature range.

[0005] However, thermoset systems based on CE resins also have disadvantages. During thermal curing, the reactive cyanate ester groups (= "N=CO-") trimerize to form cyclic triazine rings, creating polycyanurate networks with a high crosslink density. As a result of the highly crosslinked state, the cured cyanate ester resins exhibit high mechanical stability; however, the networks are brittle, meaning they have low crack and impact strength. Another significant disadvantage of cyanate ester resin systems is the hydrolysis sensitivity of both the non-crosslinked resins and the cured polycyanurates: Water penetrating the cured thermoset network causes network degradation (hydrolytic degradation), which impairs the material properties. Hydrolytic degradation also causes the formation of pores, which in turn impairs the mechanical properties and temperature resistance.In particular, highly cross-linked and higher polar thermosets based on novolak cyanate esters exhibit comparatively high water absorption and hydrolysis rates among CE resins.

[0006] It would therefore be desirable to provide suitable high-temperature stable modifiers for these already commercially available CE reactive resins, which can contribute both to a reduction in water absorption and to higher fracture toughness of the cured thermoset networks, so that these can be used commercially as matrix resins in demanding composite applications at high temperatures, preferably for the aerospace industry. It is crucial that the modifiers are compatible with the cyanate ester resins, i.e. can be processed into homogeneous mixtures, and that the cured thermoset mixtures show no signs of demixing, such as oiling or exudation of the siloxane component from the polycyanurate network or sticky surfaces. This is undesirable, since demixing changes the material properties on the one hand and impairs the matrix-fiber bond on the other.

[0007] The state of the art provides several approaches to modify polycyanurate networks with poly(diorgano)siloxanes (“silicones”).

[0008] In JP2014012759A2 and EP4056371A1, the working examples describe the preparation of mixtures of cyanate ester resins with at least two cyanate ester groups and incompatible, higher molecular weight poly(dimethyl)siloxanes with terminal phenolpropyl groups. However, complex measures are necessary to prevent phase separation of the incompatible components. For example, the mixture is thermally pre-crosslinked to form a prepolymer in solution (JP2014012759A2) or without solvent (EP4056371A1) in the presence of a catalyst that accelerates the co-reaction of the cyanate ester with the phenol OH groups. In this context, "pre-crosslinked prepolymers" are understood to mean the oligomers obtainable by partial trimerization of the cyanate ester groups with inclusion of the functional phenol groups of the siloxanes, i.e.There is both a reaction between cyanate ester groups and a co-reaction of phenol with cyanate ester groups, which also forms triazine rings. The main disadvantages of this complex procedure include the bonding of the phenol groups to the siloxane via thermally unstable propyl radicals; the use of organic solvents (JP2014012759A), which is problematic for reasons of economy, toxicity and disposal; and the production of pre-crosslinked prepolymers, which are not suitable for all processing methods, e.g. infusion processes, and their further processing both without solvents due to their higher viscosity and in a solvent.

[0009] have storage stability.

[0010] Neither document discloses how the modification of cyanate ester resins with phenolpropyl-terminated poly(diorgano)siloxanes affects properties such as water absorption or fracture toughness of the cured mixtures and to what extent low-molecular-weight phenol-terminated siloxanes with shorter chain length are compatible with cyanate ester resins without pre-crosslinking.

[0011] The present invention is therefore based on the object of providing phenol-terminated siloxanes with a distinct and short chain length. These should be suitable, for example, for modifying organic resins, i.e., for example, ensuring a reduced water absorption rate and the associated improved hydrolysis resistance and higher fracture toughness (Kic) of the modified, cured resins. At the same time, the siloxane-based modifiers should retain the advantageous properties inherent in cyanate ester resins, such as thermo-oxidative resistance and high mechanical strength. This object is achieved according to the invention by linear poly(diorgano)siloxanes with Si-bonded aromatic radicals containing at least one phenolic hydroxy group. These are compatible with organic cyanate ester resins, for example, without pre-crosslinking in the presence of a catalyst, i.e., they can be processed to form homogeneous, single-phase mixtures.The modified, cured duromer compounds show no signs of demixing, such as oiling or exudation of the siloxane-based modifier from the polycyanurate network or sticky surfaces.

[0012] Surprisingly, it has been found that with the poly(diorgano)siloxanes according to the invention it is possible to modify organic cyanate ester resins in such a way that the cured mixtures combine the properties of reduced water absorption (and thus a reduced hydrolytic network degradation), higher fracture toughness and high thermo-oxidative stability in a more advantageous manner than was previously known in the prior art.

[0013] A first aspect of the invention is therefore directed to a

[0014] Poly(diorgano)siloxane of the general formula (I)

[0015] RaR^-aSi-O-(RdR^-dSi-O-Jb-SiRcR^-c (I) wherein

[0016] R is the same or different and

[0017] - monovalent, SiC-bonded aliphatic

[0018] hydrocarbon residues, or

[0019] - monovalent, SiC-bonded, aromatic hydrocarbon radicals free of phenolic OH groups, R 1 is the same or different and denotes monovalent aromatic hydrocarbon radicals containing at least one phenolic hydroxy group, a is 2 or 3, preferably 2, b is an integer from 1 to 10, preferably 1 to 7, particularly preferably 1 to 4, c is 2 or 3, preferably 2, d is 1 or 2, preferably 2, with the proviso that per poly(diorgano)siloxane molecule of the general formula (I) one or two radicals R 1 , preferably two residues R 1 , are present.

[0020] In the present invention, "phenolic hydroxy group" means an aromatic hydroxy compound in which the hydroxy group is directly bonded to aromatic carbon atoms. Although it is clearly evident from the formulation, it should be emphasized that the aromatic hydrocarbon radical R 1 which has at least one phenolic hydroxy group and is bonded directly, i.e. via an aromatic carbon atom, to a silicon atom.

[0021] Surprisingly, it is the short-chain

[0022] Poly(diorgano)siloxanes according to the invention demonstrate outstanding compatibility with the plastics to be modified. In contrast, the longer-chain poly(diorgano)siloxanes known from the prior art exhibit a distinct tendency to leach oil from the plastic composite.

[0023] The monovalent, SiC-bonded aliphatic

[0024] Hydrocarbon radicals R preferably have ether (=COC=), hydroxy (-OH) and / or epoxide (=CQC=) groups.

[0025] In a further embodiment, the monovalent, SiC-bonded, aromatic hydrocarbon radicals R free of phenolic OH groups can be interrupted by at least one heteroatom. The at least one heteroatom can be selected from the group consisting of O, S, N, P, preferably O.

[0026] The poly(diorgano)siloxane according to the invention can be solid or liquid at 23°C and 1013 hPa, preferably liquid.

[0027] In a particular embodiment, the poly(diorgano)siloxane has a weight average molar mass Mw of 300 to 2000 g / mol, preferably 300 g / mol to 1000 g / mol, particularly preferably 300 g / mol to 700 g / mol.

[0028] In a particular embodiment, the poly(diorgano)siloxane has a number average molar mass Mn of 300 to 1500 g / mol, preferably 300 g / mol to 1000 g / mol, particularly preferably 300 g / mol to 700 g / mol.

[0029] In a preferred embodiment, R is selected from the group consisting of

[0030] - Alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl, tert-pentyl radical;

[0031] Hexyl radicals, such as the n-hexyl radical; - Heptyl radicals, such as the n-heptyl radical;

[0032] - octyl radicals, such as the n-octyl radical and iso-octyl radicals, such as the 2,4,4-trimethylpentyl and the 2,2,4-trimethylpentyl radical;

[0033] - nonyl radicals, such as the n-nonyl radical;

[0034] - Decyl radicals, such as the n-decyl radical; dodecyl radicals, such as the n-dodecyl radical;

[0035] - Hexadecyl radicals, such as the n-hexadecyl radical;

[0036] - octadecyl radicals, such as the n-octadecyl radical;

[0037] - cycloalkyl radicals, such as the cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl radicals;

[0038] - alkenyl radicals, such as vinyl, allyl, cyclopentenyl and cyclohexenyl radicals; and

[0039] - Epoxy residues, such as the 3-glycidoxypropyl, oxiran-2-yl and 2-(3,4-epoxycyclohexyl)ethyl residue.

[0040] In a preferred embodiment, R is selected from the group consisting of

[0041] - Aryl radicals, such as the phenyl, biphenyl, cumylphenyl, benzylphenyl, naphthyl, anthryl and phenanthryl radical;

[0042] - alkaryl residues, such as tolyl, xylyl and ethylphenyl residues;

[0043] - aralkyl radicals, such as the benzyl, cumyl, a- and b-phenylethyl radicals;

[0044] - alkoxyaryl residues, such as the methoxyphenyl residue;

[0045] - aryloxyaryl residues, such as the phenyloxyphenyl residue;

[0046] - halogenaryl radicals, such as fluorophenyl, chlorophenyl, bromophenyl and trifluoromethylphenyl radicals; and

[0047] - heterocyclic aromatic hydrocarbon radicals, such as pyridyl, pyrazinyl, quinolinyl, furyl radicals, and the (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxid-10-yl)ethyl radical. In a preferred embodiment, R represents a monovalent, SiC-bonded alkyl radical having 1 to 8 carbon atoms or an aryl radical. More preferably, R is a methyl radical or a phenyl radical, especially a methyl radical.

[0048] R 1 is in a preferred embodiment selected from a compound described by the following formula (II),

[0049] (II), wherein

[0050] R 4 , R 5 , R 6 , R 7 and R 8each independently of one another denotes a hydrogen atom, a hydroxy group or a hydrocarbon radical having 1 to 18 carbon atoms, optionally containing hydroxy groups and optionally interrupted by at least one heteroatom, with the proviso that in formula (II) at least one radical R 4 , R 5 , R 6 , R 7 or R 8 is or contains a phenolic hydroxy group.

[0051] Although not explicitly expressed in formula (II), as a further embodiment of the invention, two or more radicals R 4 , R 5 , R 6 , R 7 and R 8 are divalent hydrocarbon radicals, optionally containing hydroxyl groups and optionally interrupted by at least one heteroatom, and together form one or more ring structures. For example, R 5 and R 6together form a ring, as in 5,6,7,8-tetrahydro-l-naphthol or 1-naphthol.

[0052] R 4 , R 5 , R 6 , R 7 and R 8 can each independently of one another represent a hydrogen atom, a hydroxy group or a hydrocarbon radical having 1 to 8 carbon atoms, optionally containing hydroxy groups and optionally bonded via an oxy (-O-) unit.

[0053] A preferred poly(diorgano)siloxane is characterized in that R 6 represents a hydroxy group and residue R 4 , R 5 , R 7 and R 8 each independently of one another represents a hydrogen atom or a hydrocarbon radical having 1 to 12 carbon atoms, optionally bonded via an oxy (-O-) unit.

[0054] In a preferred embodiment, R 6 a hydroxy group and residue R 4 , R 5 , R 7 and R 8each independently hydrogen atom or a hydrocarbon radical having 1 to 4 carbon atoms.

[0055] In a preferred poly(diorgano)siloxane, R 6 a hydroxy group and residue R 4 , R 5 , R 7 and R 8 Hydrogen atom.

[0056] In a preferred embodiment, R 1 selected from the group consisting of hydroxyphenyl [-CeHa(OH)]-, hydroxy (methyl)phenyl [-CeH3(OH)(CHa)]-, hydroxy (dimethyl)phenyl [-CeHa(OH)(CHaJa]-, hydroxy (ethyl)phenyl [-C6Ha(OH)(CH2CH3)]-, hydroxy (methyl)(isopropyl)phenyl [-CeH3(OH)(CH3)(CH). (CH3)2)]. [-CeH3(OH)(CeHs)]-,

[0057] Hydroxy (benzyl)phenyl [-CeHs(OH)(CH2(CeHs))]- and (hydroxycumyl)phenyl [-CeHa(C (CH3)2)(Cefh (OH))]- radical, preferably selected from the group consisting of hydroxyphenyl, hydroxy (methyl)phenyl, hydroxy (dimethyl)phenyl,

[0058] Hydroxy (ethyl)phenyl and hydroxy (methyl) (iso-propyl)phenyl radical, in particular selected from hydroxyphenyl radical.

[0059] Examples of the poly(diorgano)siloxane according to the invention can correspond to one of the following formulas (IIIa), (IIIb), (IIIc), (IV) to (XII), preferably formulas (IIIa), (IIIb), (IIIc), (VI), (X) and (XI), particularly preferably formulas (IIIa), (X) and (XI):

[0060] (X) where R 9 is selected from the group consisting of Me,

[0061] Ph, Vi (corresponds to -CH=CH2), H, especially Me,

[0062] (XII), wherein Me is methyl, Ph is phenyl, m is an integer from 2-11, preferably from 2-8, more preferably from 2-5; n is an integer from 1-10, preferably from 1-7, more preferably from 1-4 and o is an integer from 1-10, preferably from 1-7, more preferably from 1-4, with the proviso that the sum of n + o is 2-11, preferably 2-8, more preferably 2-5.

[0063] The poly(diorgano)siloxane according to the invention is particularly preferably one of the formulas (IIIa), (X) or (XI) with m being 2 to 5.

[0064] In particular, the poly(diorgano)siloxane according to the invention is one of the formulas (IIIa) and (X) with m being 2 to 5. In particular, the poly(diorgano)siloxane according to the invention is one of the formula (XI) with m being 3.

[0065] A further aspect of the invention is directed to a process for preparing the poly(diorgano)siloxane according to the invention, comprising the following steps in the order given:

[0066] (A) Providing an aromatic

[0067] Hydrocarbon compound according to the chemical formula

[0068] (XIII)

[0069] Fd-x (XIII), where

[0070] R 1 a monovalent aromatic compound containing at least one phenolic hydroxy group

[0071] hydrocarbon residue, and

[0072] X represents F, CI, Br or I, preferably CI, Br or I, more preferably Br or CI, especially CI;

[0073] (B) protecting the at least one phenolic hydroxy group in R^'-X via a suitable protecting group;

[0074] (C) converting the protected compound R^'-X obtained after step (B) into a metal organyl R 1-»!, where M is preferably Li, Mg-X or Zn-X, in particular Li and Mg-X; (D) reacting the organometallic compound obtained after step (C) with a siloxane according to chemical formula (XIV)

[0075] RaY3-aSi-O-(RdY2-dSi-O-)b-SiR c Y3-c (XIV), where

[0076] R is the same or different and

[0077] - monovalent, SiC-bonded aliphatic

[0078] hydrocarbon residues, or

[0079] - monovalent, SiC-bonded, aromatic hydrocarbon radicals free of phenolic OH groups,

[0080] Y is the same or different and

[0081] represents Cl, MeO, EtO or OiPr, in particular Cl, a is 2 or 3, preferably 2, b is an integer from 1 to 10, preferably 1 to 7, particularly preferably 1 to 4, c is 2 or 3, preferably 2, d is 1 or 2, preferably 2; and

[0082] (E) Deprotecting the protected poly(diorgano)siloxane obtained after step (D); to obtain the poly(diorgano)siloxane of the invention as described above. The conversion of the protected compound R^'-X obtained after step (B) to a metal organyl R^M, if M is Mg-X, represents a Grignard reaction and follows the reaction procedure suitable for such a reaction under suitable reaction conditions.

[0083] It should be noted that in the conversion reaction in step (D) the unit Y is replaced by the unit R 1 to produce the poly(diorgano)siloxane of the invention.

[0084] Protection in the sense of the invention is to be understood as a reaction of the phenolic hydroxy group to be protected with a suitable protecting group to form an ether linkage to this protecting group.

[0085] Deprotection in the sense of the invention is to be understood as removal of the protecting group with regeneration of the phenolic hydroxy group present before protection.

[0086] The monovalent, SiC-bonded aliphatic hydrocarbon radicals R preferably have ether (=COC=), hydroxy (-OH) and / or epoxide (=CQC=) groups.

[0087] In a further embodiment, the monovalent, SiC-bonded, aromatic hydrocarbon radicals R free of phenolic OH groups can be interrupted by at least one heteroatom. The at least one heteroatom can be selected from the group consisting of O, S, N, P, preferably O.

[0088] In a preferred embodiment, R is selected from the group consisting of - alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-pentyl, isopentyl, neo-pentyl, tert-pentyl radical;

[0089] - Hexyl radicals, such as the n-hexyl radical;

[0090] - heptyl radicals, such as the n-heptyl radical;

[0091] - octyl radicals, such as the n-octyl radical and iso-octyl radicals, such as the 2,4,4-trimethylpentyl and the 2,2,4-trimethylpentyl radical;

[0092] - nonyl radicals, such as the n-nonyl radical;

[0093] - Decyl radicals, such as the n-decyl radical; dodecyl radicals, such as the n-dodecyl radical;

[0094] - Hexadecyl radicals, such as the n-hexadecyl radical;

[0095] - octadecyl radicals, such as the n-octadecyl radical;

[0096] - cycloalkyl radicals, such as the cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl radicals;

[0097] - alkenyl radicals, such as vinyl, allyl, cyclopentenyl and cyclohexenyl radicals; and

[0098] - Epoxy residues, such as the 3-glycidoxypropyl, oxiran-2-yl and 2-(3,4-epoxycyclohexyl)ethyl residue.

[0099] In a preferred embodiment, R is selected from the group consisting of

[0100] - Aryl radicals, such as the phenyl, biphenyl, cumylphenyl, benzylphenyl, naphthyl, anthryl and phenanthryl radical;

[0101] - alkaryl residues, such as tolyl, xylyl and ethylphenyl residues;

[0102] - aralkyl radicals, such as the benzyl, cumyl, a- and b-phenylethyl radicals;

[0103] - alkoxyaryl residues, such as the methoxyphenyl residue;

[0104] - aryloxyaryl radicals, such as the phenyloxyphenyl radical;

[0105] - halogenaryl radicals, such as fluorophenyl, chlorophenyl, bromophenyl and trifluoromethylphenyl radicals; and

[0106] - heterocyclic aromatic hydrocarbon residues, such as pyridyl, pyrazinyl, quinolinyl, furyl residues and the (9,10-dihydro-9-oxa-10-phosphaphenanthren-10-oxid-10-yl)ethyl residue.

[0107] In a preferred embodiment, R represents a monovalent, SiC-bonded alkyl radical having 1 to 8 carbon atoms or an aryl radical. More preferably, R is a methyl radical or a phenyl radical, in particular a methyl radical.

[0108] R 1 is in a preferred embodiment selected from a compound described by the following formula (II),

[0109] (II), wherein

[0110] R 4 , R 5 , R 6 , R 7 and R 8 each independently of each other

[0111] hydrogen atom, a hydroxyl group or a hydrocarbon radical having 1 to 18 carbon atoms, optionally containing hydroxyl groups and optionally interrupted by at least one heteroatom, with the proviso that in formula (II) at least one radical R 4 , R 5 , R 6 , R 7 or R 8is or contains a phenolic hydroxy group.

[0112] Although not explicitly expressed in formula (II), as a further embodiment of the invention, two or more radicals R 4 , R 5 , R 6 , R 7 and R 8 are divalent hydrocarbon radicals, optionally containing hydroxyl groups and optionally interrupted by at least one heteroatom, and together form one or more ring structures. For example, R 5 and R 6 together form a ring, as in 5,6,7,8-tetrahydro-l-naphthol or 1-naphthol.

[0113] R 4 , R 5 , R 6 , R 7 and R 8 can each independently of one another be hydrogen atom, a hydroxy group or a hydrocarbon radical having 1 to 8 carbon atoms, optionally containing hydroxy groups and optionally bonded via an oxy (-O-) unit.

[0114] carbon atoms.

[0115] A preferred poly(diorgano)siloxane is characterized in that R 6 represents a hydroxy group and residue R 4 , R 5 , R 7 and R 8 each independently of one another represents a hydrogen atom or a hydrocarbon radical having 1 to 12 carbon atoms, optionally bonded via an oxy (-O-) unit.

[0116] In a preferred embodiment, R 6 a hydroxy group and residue R 4 , R 5 , R 7 and R 8 each independently hydrogen atom or a hydrocarbon radical having 1 to 4 carbon atoms.

[0117] In a preferred poly(diorgano)siloxane, R 6 a hydroxy group and residue R 4 , R 5 , R 7 and R 8 Hydrogen atom.

[0118] In a preferred embodiment, R 1selected from the group consisting of hydroxyphenyl [-CeHa(OH)]-, hydroxy (methyl)phenyl [-CeH3(OH)(CHa)]-, hydroxy (dimethyl)phenyl [-CeHa(OH)(CHaJa]-, hydroxy (ethyl)phenyl [-C6Ha(OH)(CH2CH3)]-, hydroxy (methyl)(isopropyl)phenyl [-CeH3(OH)(CH3)(CH). (CH3)2)]. [-CeH3(OH)(CeHs)]-, hydroxy (benzyl)phenyl [-CeHs(OH)(CH2(CeHs))]- and (hydroxycumyl)phenyl [-CeHa(C(CH3)2)(CeHs(OH))]- radical, preferably selected from the group consisting of hydroxyphenyl, hydroxy(methyl)phenyl, hydroxy(dimethyl)phenyl, hydroxy(ethyl)phenyl and hydroxy(methyl)(isopropyl)phenyl radical, in particular selected from hydroxyphenyl radical.

[0119] In a preferred embodiment, the suitable protecting group in step (B) is that selected from benzyl, benzyl derivatives, allyl radicals, tetrahydropyran (THP), methoxymethyl (MOM), silyl ethers such as trimethylsilyl, p-methoxybenzyl, benzyloxymethyl, preferably benzyl and allyl, more preferably benzyl.

[0120] In the event that a benzyl protecting group is introduced, the protection in step (B) is preferably carried out by reacting I^-X with benzyl bromide or benzyl chloride, in particular in an amount of 1.0 equivalent of benzyl bromide or benzyl chloride. During protection, 1.1–1.4 equivalents of K2CO3 may also be added. The reaction is preferably carried out in a suitable solvent, for example selected from acetonitrile and acetone. The reaction is preferably carried out at room temperature of 23°C or the boiling temperature of the solvent used. The protection reaction in step (B) is usually carried out over a period of 2 to 18 hours, preferably 2 to 12 hours.

[0121] If an allyl protecting group is introduced, the protection in step (B) is preferably carried out by reacting IV'-X with allyl bromide or allyl chloride, preferably allyl bromide, in particular in an amount of 1.1 equivalents of allyl bromide or allyl chloride. During protection, 1.1-1.5 equivalents of K2CO3 may also be added. The reaction is preferably carried out in a suitable solvent, for example selected from DMF and acetone. The reaction is preferably carried out at room temperature of 23°C or at 60°C. In particular, when DMF is used as the solvent, the reaction takes place at 60°C or at room temperature when acetone is used as the solvent. The protection reaction in step (B) is usually carried out over a period of 6 to 18 hours when DMF is used as the solvent or 4 to 8 hours when acetone is used as the solvent.

[0122] In the case where a THP protecting group is introduced, protection in step (B) is preferably carried out by reacting IV'-X with dihydropyran, especially in an amount of 1.10 equivalents of dihydropyran. 4-Bromophenol and / or hydrochloric acid may also be added during protection. Typically, the protection reaction in step (B) is carried out over a period of 30 to 120 minutes and / or at room temperature.

[0123] In the case where a MOM protecting group is introduced, protection in step (B) is preferably carried out by reacting I^-X with (chloromethyl)methyl ether, especially in an amount of 1.0 to 1.5 equivalents of (chloromethyl)methyl ether. K2CO3 may also be added during protection. The reaction is preferably carried out in a suitable solvent, for example, acetone.

[0124] The conversion of I^-X to a metal organyl R^M in step (C) is preferably carried out by, in the case that M is Li, reacting R^'-X with an organolithium compound, in particular n-BuLi; or in the case that M is Mg-X, reacting I^-X with Mg to form a Grignard compound; or in the case that M is Zn-X, reacting I^-X with Zn to form a zinc organyl compound.

[0125] In a preferred embodiment, the deprotection in step (E) is carried out using a suitable reaction procedure known in the art. The deprotection can be carried out, for example, hydrogenolytically or acidically, in particular hydrogenolytically. Whether the deprotection is carried out hydrogenolytically or acidically depends in particular on the protecting group used. Thus, in the case of protecting groups selected from benzyl, benzyl derivatives, and allyl radicals, the deprotection can be carried out hydrogenolytically. In the case of protecting groups selected from tetrahydropyran (THP), methoxymethyl (MOM), silyl ethers such as trimethylsilyl, p-methyloxybenzyl, and benzyloxymethyl, the deprotection is carried out acidically.

[0126] Hydrogenolytic deprotection is based on the cleavage of a covalent bond using hydrogen and suitable catalysts. Suitable catalysts include heterogeneous catalysts, such as those using elements of the iron-platinum group. Examples of such catalysts are Pd on carbon (Pd / C) or Raney nickel. The catalyst quantity is preferably 0.1-2 wt.% based on the total mass of the reaction mixture.

[0127] Hydrogenolytic deprotection can be performed in a pressure autoclave or in a glass flask. Hydrogen can be added directly (e.g., 1 atm H2) or generated in situ from suitable starting materials (e.g., ammonium formate). When using starting materials for the in situ generation of hydrogen, 1.5–3 equivalents of starting material are preferably used per OH group to be deprotected.

[0128] Hydrogenolytic deprotection is preferably carried out at temperatures in the range of 23 °C to 80 °C and / or for 1-18 h and / or at a pressure of 1-20 bar.

[0129] The poly(diorgano)siloxane according to the invention thus prepared is characterized in particular by being a distinct poly(diorgano)siloxane. "Distinct siloxanes" within the meaning of the invention refer to siloxanes with a substantially uniform chain length (i.e., number of repeating units) and / or a particularly narrow molecular weight distribution. A suitable measure for describing such a narrow molecular weight distribution is, for example, the polydispersity index (PDI), which is indicated by the ratio of Mw / Mn. The poly(diorgano)siloxanes according to the invention preferably have a PDI in the range from 0.8 to 1.5, preferably from 1.0 to 1.5, in particular from 1.1 to 1.3.

[0130] To determine the PDI, various methods known to the person skilled in the art can be used, such as gel permeation chromatography.

[0131] In contrast, it should be noted that poly(diorgano)siloxanes prepared by state-of-the-art processes (usually equilibration) exhibit a broad molecular weight distribution. The PDI of such siloxanes is typically in the range of at least 2.0 (Noll, "Chemistry and Technology of Silicones").

[0132] "Equilibration" in the sense of the invention is understood to mean an equilibrium-forming rearrangement of siloxane bonds, which is based on the breaking and reforming of siloxane bonds. Equilibration is to be regarded as a special case of polymerization in which mixtures of siloxanes of different molecular sizes are brought into molecular equilibrium, i.e., equilibrated. The process has the effect that a siloxane mixture whose molecular weight distribution curve exhibits several maxima is converted into a polymeric molecular assembly whose molecular size is characterized by only one broad maximum. Statistical mixtures of siloxanes with a broad molecular weight distribution are obtained.

[0133] A further aspect of the present invention is directed to the use of the poly(diorgano)siloxane according to the invention as a modifier in organic resins, preferably as a toughening modifier, hydrophobizing agent, modifier for improving flame resistance, thermo-oxidative properties, dielectric properties, moisture resistance, chemical resistance and / or processing properties.

[0134] Examples of organic resins are epoxy resins,

[0135] Cyanate ester resins, novolak resins, phenolic resins, UP resins,

[0136] Vinyl ester resins and BT resins, especially cyanate ester resins.

[0137] Examples of implementation

[0138] The following examples were carried out at a pressure of the ambient atmosphere, i.e. at about 1013 hPa, and at room temperature, i.e. about 23°C or a temperature which is reached when the reactants come together at room temperature without additional heating or cooling, and describe the basic feasibility of the present invention, without, however, limiting it to the contents disclosed therein.

[0139] Synthesis of poly(diorgano)siloxanes

[0140] Example 1 (Tetrasiloxane = (Cel^OBn)SiMe2-[OSiMe2]2- OSiMe2(C6H4OBn))

[0141] 125 g of 1-(benzyloxy)-4-bromobenzene was dissolved in TEA (1 L), and 200 mL of a 2.5M n-butyllithium solution in hexane was added dropwise at -78°C. The mixture was stirred, and 83 mL of 1,7-dichlorooctamethyltetrasiloxane was added. The cooling bath was removed and the mixture warmed to room temperature. After addition of 20 mL of triethylamine, 300 mL of saturated aqueous ammonium chloride solution was added, and the phases were separated. After extraction with diethyl ether, the combined organic phases were dried over sodium sulfate and filtered. The solvent was removed, and 153 g of a colorless solid was obtained.

[0142] Example 1 (Adaptation)

[0143] 125 g of 1-(benzyloxy)-4-bromobenzene was dissolved in TEA (0.5 L), and 200 mL of a 2.5M n-butyllithium solution in hexane was added dropwise at -78°C. The mixture was stirred, and 80 mL of 1,7-dichlorooctamethyltetrasiloxane was added. The cooling bath was removed and the mixture warmed to room temperature. After adding 20 mL of triethylamine, 300 mL of saturated aqueous ammonium chloride solution was added, and the phases were separated. After extraction with diethyl ether, the combined organic phases were dried over sodium sulfate and filtered. The solvent was removed, yielding 151 g of a colorless solid. Example 2 (Monosilane = Me2Si(CeJ^OBn)2)

[0144] 20 g of 1-(benzyloxy)-4-bromobenzene was dissolved in 200 mL of THF, and 200 mL of a 2.5M n-butyllithium solution in hexane was added dropwise at -78°C over 30 minutes, followed by a further addition of 50 mL of THF. The mixture was stirred, and 4.7 mL of 1,1-dichlorodimethylsilane was added. The cooling bath was removed, warmed to room temperature, and stirred for 1 hour. Water was then added and extracted with diethyl ether. The combined organic phases were dried over sodium sulfate and filtered. The solvent was removed, yielding 15 g of a colorless solid. The resulting material remained stable in air for 2 months.

[0145] Example 3 (Trisiloxane = (CeJ^OBn)SiMe2-OSiMe2-OSiMe2(CeJ^OBn))

[0146] 63 g of 1-(benzyloxy)-4-bromobenzene was dissolved in 700 mL of THF, and 100 mL of a 2.5M n-butyllithium solution in hexane was added dropwise at -78°C. The mixture was stirred, and 32 g of 1,5-dichlorohexamethyltrisiloxane were added. The cooling bath was removed and the mixture warmed to room temperature. After addition of 20 mL of triethylamine, 300 mL of saturated aqueous ammonium chloride solution was added, and the phases were separated. After extraction with diethyl ether, the combined organic phases were dried over sodium sulfate and filtered. The solvent was removed, and 54 g of a colorless solid was obtained.

[0147] Example 4 (Disiloxane = (CeJ^OBn)SiMe2-O-SiMe2(CeJ^OBn))

[0148] 63 g of 1-(benzyloxy)-4-bromobenzene was dissolved in 650 mL of THF, and 100 mL of a 2.5M n-butyllithium solution in hexane was added dropwise at -78°C. The mixture was stirred, and 23.7 g of 1,3-dichlorotetramethyldisiloxane was added. The cooling bath was removed and the mixture warmed to room temperature. After addition of 20 mL of triethylamine, 300 mL of saturated aqueous ammonium chloride solution was added, and the phases were separated. After extraction with diethyl ether, the combined organic phases were dried over sodium sulfate and filtered. The solvent was removed, and 57 g of a colorless solid was obtained.

[0149] Example 5 (Disiloxane = (Cef^OBn)SiMe2-O-SiMe2(Cef^OBn); Grignard approach)

[0150] 2.9 g of magnesium turnings were suspended in 30 mL of THF, and 0.1 g of iodine was added. A solution of 26 g of 1-(benzyloxy)-4-bromobenzene in 30 mL of THF was added dropwise. After a reaction time of 1 h, the Grignard reagent was added dropwise to 9.2 g of 1,3-dichloro-1,1,3,3-tetramethyldisiloxane in THF. The reaction mixture was stirred for 16 h and then quenched by adding water. The aqueous phase was extracted with diethyl ether, and the combined organic extracts were dried over magnesium sulfate and filtered. 22 g of a yellow solid were obtained.

[0151] Example 6 (Pentasiloxane = (C6H4OBn)SiMe2~[OSiMe2]3- OSiMe2(C6H4OBn))

[0152] 125 g of 1-(benzyloxy)-4-bromobenzene was dissolved in 800 mL of THE, and 200 mL of a 2.5M n-butyllithium solution in hexane was added dropwise at -78°C. The mixture was stirred, and 100 g of 1,9-dichlorodecamethylpentasiloxane was added. The cooling bath was removed and the mixture warmed to room temperature. After adding 20 mL of triethylamine, 300 mL of saturated aqueous ammonium chloride solution was added, and the phases were separated. After extraction with diethyl ether, the combined organic phases were dried over sodium sulfate and filtered. The solvent was removed, yielding 168 g of a colorless solid. Example 7 (Disiloxane = (C6H4OA11)SiMe2-O-SiMe2(C6H4OA11))

[0153] 48 g of l-allyloxy-4-bromobenzene were dissolved in 400 mL of THF, and 100 g of a 2.5M n-butyllithium solution in hexane were added dropwise at -78°C. After 60 minutes, 1,3-dichlorotetramethyldisiloxane was added dropwise, and the mixture was stirred for 1 h. The mixture was brought to room temperature, and 15 mL of triethylamine was added. After extraction with diethyl ether and ammonium formate, the organic phase was dried over magnesium sulfate and filtered. The solvent was removed, yielding 29 g of a light yellow oil.

[0154] Example 8 (Tetrasiloxane = (CeH4OBn)SiMe2-[OSiMe2]2- OSiMe2(CeH4OBn); Grignard approach)

[0155] 5.6 g of magnesium turnings were suspended in 60 mL of THF, and 0.1 g of tod was added. A solution of 52 g of 1-(benzyloxy)-4-bromobenzene in 60 mL of THF was added dropwise, and after a reaction time of 1 h, the Grignard reagent was added dropwise to 27.7 g of 1,5-dichloro-1,1,3,3,5,5-hexamethyltrisiloxane in THF. The reaction mixture was stirred for 2 h and then quenched by adding water. The aqueous phase was extracted with diethyl ether, and the combined organic extracts were dried over magnesium sulfate and filtered. 54 g of a yellow solid was obtained.

[0156] Deprotect

[0157] MuM408 - Ammonium formate method Si4 (tetrasiloxane

[0158] (HOC6H4)SiMe2-[OSiMe2]2-OSiMe2(C6H4OH)

[0159] 35 g of the benzyl-protected a,w-phenol substituted

[0160] Octamethyltetrasiloxane was dissolved in a 1:3 mixture of MeOH and THF. 15.1 g of ammonium formate and 2.0 g of Pd / C (10 wt%) were added, and the mixture was stirred in an autoclave at 60°C for 24 h. After releasing the pressure, the reaction mixture was filtered, diluted with ethyl acetate, and washed until neutral. The solvent was removed after drying with magnesium sulfate and filtration, yielding 18.4 g of a yellow solid.

[0161] MuM408 - Adaptation 1 (Tetrasiloxane = (HOC6H4)SiMe2~[0SiMe2]2-

[0162] OSiMe2(C6H4OH))

[0163] 35 g of the benzyl-protected a,w-phenol substituted octamethyltetrasiloxane was dissolved in a 1:5 mixture of MeOH and THF. 15.1 g of ammonium formate and 2.0 g of Pd / C (10 wt%) were added, and the mixture was stirred in an autoclave at 60°C for 12 h. After releasing the pressure, the reaction mixture was filtered, diluted with ethyl acetate, and washed until neutral. The solvent was removed after drying with magnesium sulfate and filtration, yielding 20.1 g of a yellow solid.

[0164] MuM408 - Adaptation 2 ((Tetrasiloxane = (HOC6H4)SiMe2~[OSiMe2]2-

[0165] OSiMe2(C6H4OH))

[0166] 35 g of the benzyl-protected a,w-phenol substituted octamethyltetrasiloxane was dissolved in a 1:4 mixture of MeOH and THF. 27.2 g of ammonium formate and 2.0 g of Pd / C (10 wt%) were added, and the mixture was stirred in an autoclave at 60°C for 4 h. After releasing the pressure, the reaction mixture was filtered, diluted with ethyl acetate, and washed until neutral. The solvent was removed after drying with magnesium sulfate and filtration, yielding 19.4 g of a yellow oil.

[0167] MuM408 - Adaptation 3 ((Tetrasiloxane = (HOC6H4)SiMe2~[OSiMe2]2-

[0168] OSiMe2(C6H4OH))

[0169] 35 g of the benzyl-protected a,w-phenol-substituted octamethyltetrasiloxane was dissolved in a 1:3 mixture of MeOH and THF. 27.2 g of ammonium formate and 2.0 g of Pd / C (10 wt%) were added, and the mixture was stirred at 60°C for 8 h. After removal of the catalyst, the mixture was diluted with ethyl acetate and washed until neutral. The organic phase was dried over magnesium sulfate and filtered. The solvent was removed, yielding 21.9 g of a yellow oil.

[0170] MuM417 - Hydrogen Method ((Tetrasiloxane = (HOCeH4)SiMe2-

[0171] [OSiMe2]2-OSiMe2(C6H4OH))

[0172] 15 g of the benzyl-protected a,w-phenol-substituted octamethyltetrasiloxane was dissolved in a 1:2 mixture of MeOH and THF. 1.6 g of Pd / C (10 wt%) was added, and the mixture was stirred for 16 h under hydrogen (15 bar). After removal of the catalyst, the mixture was diluted with ethyl acetate and washed until neutral. The organic phase was dried over magnesium sulfate and filtered. The solvent was removed, yielding 7.8 g of a yellow oil.

[0173] KnA2768 Si2 (Disiloxane = (HOC6H4)SiMe2-O-SiMe2(C6H4OH))

[0174] 30 g of the benzyl-protected a,w-phenol substituted

[0175] Tetramethyldisiloxane was dissolved in a 120 mL 1:3 mixture of MeOH and THF. 22.5 g of ammonium formate and 1.5 g of Pd / C (10 wt%) were added, and the mixture was stirred in an autoclave at 50°C for 10 h. After releasing the pressure, the reaction mixture was filtered, diluted with ethyl acetate, and washed until neutral. The solvent was removed after drying with magnesium sulfate and filtration, yielding 17.2 g of a brown oil. Recrystallization from toluene and n-hexane yielded a yellow solid.

[0176] 31 g of the benzyl-protected a,w-phenol-substituted hexamethyltrisiloxane was dissolved in a 110 mL 1:3 mixture of MeOH and THF. 20.5 g of ammonium formate and 1.6 g of Pd / C (10 wt%) were added, and the mixture was stirred in an autoclave at 60°C for 8 h. After releasing the pressure, the reaction mixture was filtered, diluted with ethyl acetate, and washed until neutral. The solvent was removed after drying with magnesium sulfate and filtration, yielding 18.5 g of a yellow oil.

[0177] MuM245 Si4 (Tetrasiloxane = (HOC6H4)SiMe2-[OSiMe2]2-OSiMe2(C6H4OH))

[0178] 8 g of the allyl-protected a,w-phenol substituted

[0179] Tetramethyldisiloxane was dissolved in 40 mL of a 1:3 mixture of MeOH and THF. 6.3 g of ammonium formate and 0.4 g of Pd / C (10 wt%) were added, and the mixture was stirred in an autoclave at 60°C for 6 h. After releasing the pressure, the reaction mixture was filtered, diluted with ethyl acetate, and washed until neutral. The solvent was removed after drying with magnesium sulfate and filtration, yielding 5.3 g of a yellow oil.

[0180] Molar masses

[0181] Within the scope of the present invention, the weight-average molar mass Mw and the number-average molar mass Mn, each in the unit g / mol, rounded to the nearest whole number of ten according to DIN 1333:1992-02 Section 4, are determined by size exclusion chromatography (SEC / GPC) according to DIN 55672-1 / ISO 160414-1 and ISO 160414-3 with tetrahydrofuran (THF) as the eluent. A column set based on polystyrene-co-divinylbenzene as the stationary phase, consisting of three columns with different pore size distributions, in the order of 10,000 Å, 500 Å, and 100 Å, with an exclusion size of greater than 450,000 g / mol, is calibrated against polystyrene standards. The analyses are carried out at a column temperature of 4511°C and using a refractive index detector.

[0182] Production of the test specimens

[0183] First, the cyanate ester resin (A) was heated to 80°C with thorough mixing to improve processability. Poly(diorgano)siloxane (B) was then added, and the mixture was homogenized at 110°C for one hour. Degassed for one hour at 110°C and a pressure of 10 mbar, and after breaking the vacuum with nitrogen, the mixture was immediately poured hot into a two-part, screw-on aluminum mold preheated to 160°C. The mold cavity dimensions were 200 mm x 100 mm x 6.5 mm (length x width x height) for the production of test specimens for determining fracture toughness, water absorption, thermo-oxidative stability, and for conducting dynamic mechanical analysis (DMA). To prevent sticking and leakage, the cavity surface on the inside of the mold was coated with a mold release agent (LOCTITE FREKOTE HMT-2; commercially available from Henkel AG & Co.KGaA, DE-Düsseldorf) and a 2 mm thick round cord made of fluororubber with a hardness of 75 Shore A was placed around the mold cavity. For curing, the filled molds were stored in a convection oven according to the following temperature program: 1) 18 hours curing at 180°C.

[0184] 2) Temperature increase to 200°C within 30 minutes

[0185] 3) 3 hours curing at 200°C

[0186] 4) Temperature increase within 30 minutes to 240°C

[0187] 5) 2 hours curing at 240°C.

[0188] The specimen was then allowed to cool to ambient temperature in the mold before demolding. For further use, the top 10 mm of the cured specimen side, which was open and exposed to air during curing in the mold, was cut off and discarded. The test specimens for measuring fracture toughness, water absorption, and DMA were then cut from the large, 6.5 mm high, cured specimen plate in the corresponding dimensions length x width using a diamond cut-off saw. The 2.00 mm thick test specimens for measuring water absorption were cut from the pre-sawn piece using an internal hole diamond saw from the inner part, so that all six surfaces of these test specimens were sawn.

[0189] Fracture toughness Ki c

[0190] The measurement of the fracture toughness or the critical stress intensity factor Ki cwas carried out as described in the publication "Reactive and Functional Polymers 142 (2019) 159-182" at 23°C and 50% relative humidity; the thickness of the specimens was 6.5 mm. The value for the fracture toughness Ki given in Table 1 c in MN xm -3 / 2 was rounded to two decimal places according to DIN 1333:1992-02 Section 4.

[0191] Dynamic Mechanical Analysis (DMA)

[0192] Measurement conditions:

[0193] Measuring device: ARES rheometer (TA-Instruments) • Temperature range: -100°C - 300°C

[0194] • Heating rate: 4 K / min with nitrogen purge

[0195] • Frequency: 1 Hz

[0196] • Strain: Initial 0.03%, automatically increased when

[0197] Measurement signal below threshold

[0198] For the investigations, cuboid-shaped test specimens with the dimensions length x width x height = 40 mm x 6 mm x 3 mm were used; the resulting clamping length was 25 mm.

[0199] In the present invention, the glass transition temperature TG corresponds to the maximum value of the tangent delta curve (= tan delta ma x), ie the measuring temperature at which the ratio of loss modulus G' to storage modulus G' is greatest.

[0200] The value for the glass transition temperature TG given in Table 1 was rounded to whole numbers, according to DIN 1333:1992-02 Section 4.

[0201] Water absorption

[0202] In the present invention, water absorption was determined gravimetrically after storage of the test specimens in tempered water. Cuboid-shaped test specimens with the dimensions length x width x thickness = 30.00 mm x 17.00 mm x 2.00 mm were used; the accuracy of the weight determination was j+0.01 mg. The test specimens were first dried to constant weight in a vacuum oven at 70°C and 30 mbar, with the weight being determined at 24-hour intervals. The test specimens were considered "dry" if no further weight loss was measured over a period of 48 hours. One dry test specimen was then immersed in 45 ml of deionized water in a suitable sealable container. The sealed container was then placed in a convection oven preheated to 70°C and maintained at this temperature throughout the test period.After 1600 hours, the test specimens were removed, cooled to ambient temperature, and the surfaces wiped dry with a cloth. The weight of the test specimens was then determined again. The water absorption (or weight gain) was calculated according to the formula shown in Table 1.

[0203] Value for water absorption given in % and rounded to two decimal places according to DIN 1333:1992-02 Section 4.

[0204] compatibility

[0205] The compatibility of compound (B) with cyanate ester resins (A) was visually assessed using the criteria given in Table 1:

[0206] Before curing after storing the mixture for 15 minutes at 100°C:

[0207] "+", meaning mixture is single-phase and , meaning mixture is two-phase;

[0208] After curing:

[0209] "+" = good compatibility, i.e., no visible oiling or exudation of compound (B) from the cured mixture, and = poor compatibility, i.e., visible oiling or exudation of component (B) from the cured mixture. Furthermore, the stickiness or oiliness of the air-side surface was determined using an LDPE film (GAS: 9002-88-4) and a filter paper (Whatman™ filter paper grade 589 / 2) by pressing the film or filter paper onto the surface and then peeling it off. As indicated in Table 1, the surface stickiness / oiliness was differentiated into "+" (test specimen surface dry, non-sticky, and non-oily (dry filter paper)) and (test specimen surface soft, sticky, and / or oily (moist filter paper)).

[0210] Example Bl

[0211] As described in the section "Preparation of the test specimens", 85 g of a polyphenol cyanate resin (CAS 87397-54-4; commercially available under the trade name Primaset® PT-15 from Arxada Ltd., CH-4002 Basel) as component (A) are mixed with 15 g of the previously prepared modifier "MuM408 - Si4" as component (B) and then processed.

[0212] The results can be found in Table 1.

[0213] Example B2

[0214] Example B1 is repeated with the modification that polyphenol cyanate resin PRIMASET® PT-30 (CAS 87397-54-4; commercially available from Arxada Ltd., CH-4002 Basel) is used instead of polyphenol cyanate resin PRIMASET® PT-15 and modifier "KnA2795 Si3" is used instead of modifier "MuM408 - Si4".

[0215] The results can be found in Table 1.

[0216] Comparison example VI

[0217] The procedure described in Example Bl was repeated with the modification that no component (B) was added to component (A).

[0218] The results can be found in Table 1. Comparative example V2

[0219] The procedure described in Example B2 was repeated except that no component (B) was added to component (A).

[0220] The results can be found in Table 1.

[0221] The results can be found in Table 1. Table 1 not assessed

[0222] The present invention is further characterized by the following

[0223] Points characterized:

[0224] 1. Poly(diorgano)siloxane of the general formula (I)

[0225] RaR^-aSi-O-(RdRV dSi-O-)b-SiRcR^-c (I) where

[0226] R is the same or different and

[0227] - monovalent, SiC-bonded aliphatic

[0228] hydrocarbon residues, or

[0229] - monovalent, SiC-bonded, aromatic hydrocarbon radicals free of phenolic OH groups,

[0230] R 1 is the same or different and denotes monovalent aromatic hydrocarbon radicals containing at least one phenolic hydroxy group, a is 2 or 3, preferably 2, b is an integer from 1 to 10, preferably 1 to 7, particularly preferably 1 to 4, c is 2 or 3, preferably 2, d is 1 or 2, preferably 2, with the proviso that per poly(diorgano)siloxane molecule of the general formula (I) one or two radicals R 1 , preferably two residues R 1 , are present.

[0231] 2. Poly(diorgano)siloxane according to item 1, wherein the monovalent, SiC-bonded aliphatic hydrocarbon radicals R further contain ether (=COC=), hydroxy (-OH) and / or epoxide (=CQC=) groups.

[0232] 3. Poly(diorgano)siloxane according to item 1, wherein the monovalent, SiC-bonded, aromatic hydrocarbon radicals R free of phenolic OH groups are interrupted by at least one heteroatom.

[0233] 4. Poly(diorgano)siloxane according to item 3, wherein the at least one heteroatom is selected from the group consisting of

[0234] 0, S, N, P, preferably 0.

[0235] 5. Poly(diorgano)siloxane according to one of the preceding points, which is solid or liquid at 23°C and 1013 hPa, preferably liquid.

[0236] 6. Poly(diorgano)siloxane according to one of the preceding points, which has a weight average molecular weight Mw of 300 to 2000 g / mol, preferably 300 g / mol to 1000 g / mol, particularly preferably 300 g / mol to 700 g / mol.

[0237] 7. Poly(diorgano)siloxane according to any one of the preceding points, which has a number-average molar mass Mn of preferably 300 to 1500 g / mol, more preferably 300 g / mol to 1000 g / mol, particularly preferably 300 g / mol to 700 g / mol. 8. Poly(diorgano)siloxane according to any one of the preceding points, wherein R is selected from the group consisting of

[0238] - Alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl, tert-pentyl radical;

[0239] - Hexyl radicals, such as the n-hexyl radical;

[0240] - heptyl radicals, such as the n-heptyl radical;

[0241] - octyl radicals, such as the n-octyl radical and iso-octyl radicals, such as the 2,4,4-trimethylpentyl and the 2,2,4-trimethylpentyl radical;

[0242] - nonyl radicals, such as the n-nonyl radical;

[0243] - Decyl radicals, such as the n-decyl radical; dodecyl radicals, such as the n-dodecyl radical;

[0244] - Hexadecyl radicals, such as the n-hexadecyl radical;

[0245] - octadecyl radicals, such as the n-octadecyl radical;

[0246] - cycloalkyl radicals, such as the cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl radicals;

[0247] - alkenyl radicals, such as vinyl, allyl, cyclopentenyl and cyclohexenyl radicals; and

[0248] - Epoxy residues, such as the 3-glycidoxypropyl, oxiran-2-yl and 2-(3,4-epoxycyclohexyl)ethyl residue.

[0249] 9. Poly(diorgano)siloxane according to any one of the preceding points, wherein R is selected from the group consisting

[0250] - Aryl radicals, such as the phenyl, biphenyl, cumylphenyl, benzylphenyl, naphthyl, anthryl and phenanthryl radical;

[0251] - alkaryl residues, such as tolyl, xylyl and ethylphenyl residues;

[0252] - aralkyl radicals, such as the benzyl, cumyl, a- and b-phenylethyl radicals;

[0253] - alkoxyaryl residues, such as the methoxyphenyl residue;

[0254] - aryloxyaryl residues, such as the phenyloxyphenyl residue;

[0255] - halogenaryl radicals, such as fluorophenyl, chlorophenyl, bromophenyl and trifluoromethylphenyl radicals; and - heterocyclic aromatic hydrocarbon radicals, such as pyridyl, pyrazinyl, quinolinyl, furyl radicals and the (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxid-10-yl)ethyl radical.

[0256] 10. Poly(diorgano)siloxane according to one of the preceding points, wherein R is a monovalent, SiC-bonded alkyl radical having 1 to 8 carbon atoms or an aryl radical, preferably a methyl radical or a phenyl radical, in particular a methyl radical.

[0257] 11. Poly(diorgano)siloxane according to any one of the preceding points, wherein R 1 is selected from a compound described by the following formula (II),

[0258] (II), wherein

[0259] R 4, R 5 , R 6 , R 7 and R 8 each independently of each other

[0260] hydrogen atom, a hydroxyl group or a hydrocarbon radical having 1 to 18 carbon atoms, optionally containing hydroxyl groups and optionally interrupted by at least one heteroatom, with the proviso that in formula (II) at least one radical R 4 , R 5 , R 6 , R 7 or R 8 is or contains a phenolic hydroxy group. 12. Poly(diorgano)siloxane according to item 11, where R 4 , R 5 , R 6 , R 7 and R 8 each independently of one another represents a hydrogen atom, a hydroxy group or a hydrocarbon radical having 1 to 8 carbon atoms, optionally containing hydroxy groups and optionally bonded via an oxy (-O-) unit.

[0261] 13. Poly(diorgano)siloxane according to item 11 or 12, where R 6represents a hydroxy group and residue R 4 , R 5 , R 7 and R 8 each independently of one another represents a hydrogen atom or a hydrocarbon radical having 1 to 12 carbon atoms, optionally bonded via an oxy (-O-) unit.

[0262] 14. Poly(diorgano)siloxane according to any one of items 11-13, wherein radical R 6 represents a hydroxy group and residue R 4 , R 5 , R 7 and R 8 each independently represents a hydrogen atom or a hydrocarbon radical having 1 to 4 carbon atoms.

[0263] 15. Poly(diorgano)siloxane according to any one of items 11-14, wherein R 6 represents a hydroxy group and residue R 4 , R 5 , R 7 and R 8 hydrogen atom.

[0264] 16. Poly(diorgano)siloxane according to any one of the preceding points, wherein R 1is selected from the group consisting of hydroxyphenyl [-CeHa(OH)]-, hydroxy (methyl)phenyl

[0265] [-CeH3(OH)(CHa)]-, hydroxy (dimethyl)phenyl [-CeHa(OH)(CHaJa]-,

[0266] Hydroxy (ethyl)phenyl [-C6Ha(OH)(CH2CH3)]-, Hydroxy (methyl)(isopropyl)phenyl [-CeH3(OH)(CH3)(CH (CH3)2)]-, Hydroxy (methoxy)phenyl [-CeH3(OH)(OCH3)]-, Hydroxy (phenyloxy)phenyl [-CeH3(OH)(OCeHs)]-, (Hydroxyphenyl)phenyl [-CeHa(CeHa(OH))]-, hydroxynaphthyl [-CioHe(OH)]-, hydroxy (phenyl)phenyl [-CeH3(OH)(CeHs)]-, hydroxy (benzyl)phenyl

[0267] [-CeHs(OH)(CH2(CeHs))]- and (hydroxycumyl)phenyl

[0268] [-C6H3(C(CH3)2)(C6H4(OH))] radical, preferably selected from the group consisting of hydroxyphenyl, hydroxy(methyl)phenyl,

[0269] Hydroxy (dimethyl)phenyl, hydroxy (ethyl)phenyl and

[0270] Hydroxy(methyl)(isopropyl)phenyl radical, in particular selected from hydroxyphenyl radical. 17. Poly(diorgano)siloxane according to one of the preceding

[0271] Points which correspond to one of the following formulas (IIIa), (IIIb), (IIIc), (IV) to (XII), preferably formulas (IIIa), (IIIb), (IIIc), (VI), (X) and (XI), particularly preferably formulas (IIIa), (X) and (XI)

[0272] (IV),

[0273] (X)

[0274] (XI), where R 9 is selected from the group consisting of Me,

[0275] Ph, Vi, H, especially Me,

[0276] (XII), wherein Me is methyl radical, Ph is phenyl radical, m is an integer from 2-11, preferably from 2-8, more preferably from 2-5; n is an integer from 1-10, preferably from 1-7, more preferably from 1-4 and o is an integer from 1-10, preferably

[0277] 1-7, more preferably 1-4, with the proviso that the sum of n + o is 2-11, preferably 2-8, more preferably 2-5.

[0278] 18. A process for preparing a poly(diorgano)siloxane according to any one of items 1-17, comprising the following steps in the order given:

[0279] (A) Providing an aromatic

[0280] Hydrocarbon compound according to the chemical formula

[0281] (XIII) R T -X (XIII), wherein

[0282] R 1 a monovalent aromatic compound containing at least one phenolic hydroxy group

[0283] hydrocarbon residue, and

[0284] X represents F, Ci, Br or I, preferably Ci, Br or I, more preferably Ci or Br;

[0285] (B) protecting the at least one phenolic hydroxy group in R^'-X via a suitable protecting group;

[0286] (C) converting the protected compound R^'-X obtained after step (B) into a metal organyl R^M, where M is preferably Li, Mg-X or Zn-X, in particular Li and Mg-X;

[0287] (D) reacting the organometallic compound obtained after step (C) with a siloxane according to chemical formula (XIV)

[0288] RaY3-aSi-O-(RdY2-dSi-O-)b-SiR c Y3-c (XIV), where

[0289] R is the same or different and

[0290] - monovalent, SiC-bonded aliphatic

[0291] hydrocarbon residues, or

[0292] - monovalent, SiC-bonded, aromatic hydrocarbon radicals free of phenolic OH groups, Y is the same or different and

[0293] O1, MeO, EtO or OiPr, in particular O1, a is 2 or 3, preferably 2, b is an integer from 1 to 10, preferably 1 to 7, particularly preferably 1 to 4, c is 2 or 3, preferably 2, d is 1 or 2, preferably 2; and

[0294] (E) deprotecting the protected poly(diorgano)siloxane obtained according to step (D) to obtain the poly(diorgano)siloxane according to any one of items 1-17.

[0295] 19. The process according to item 18, wherein the suitable protecting group in step (B) is selected from benzyl, benzyl derivatives, allyl radicals, tetrahydropyran (THP), methoxymethyl (MOM), silyl ethers such as trimethylsilyl, p-methyloxybenzyl, benzyloxymethyl, preferably benzyl and allyl, more preferably benzyl.

[0296] 20. Process according to item 18 or 19, wherein the conversion to a metal organyl in step (C) is carried out by, in the case where M is Li, reacting I^-X with an organolithium compound, in particular n-BuLi; or in the case where M is Mg-X, reacting IV'-X with Mg to form a Grignard compound; or in the case where M is Zn-X, reacting I^-X with Zn to form a Zn organyl compound.

[0297] 21. Process according to any one of items 18-20, wherein the deprotection in step (E) is carried out hydrogenolytically or acidically, preferably hydrogenolytically.

[0298] 22. Use of a poly(diorgano)siloxane according to any one of items 1-17 as a modifier in organic resins, preferably as a toughening modifier, hydrophobizing agent, modifier for improving flame resistance, thermo-oxidative properties, dielectric properties, moisture resistance, chemical resistance and / or processing properties.

[0299] 23. Use according to item 22, wherein the resin is selected from epoxy resins, cyanate ester resins, novolak resins, phenolic resins, UP resins, vinyl ester resins and BT resins, in particular from cyanate ester resins.

Claims

Claims 1. Poly(diorgano)siloxane of the general formula (I) RaR^-aSi-O-(RdRV dSi-O-)b-SiRcR^-c (I) where R is the same or different and - monovalent, SiC-bonded aliphatic hydrocarbon residues, or - monovalent, SiC-bonded, aromatic hydrocarbon radicals free of phenolic OH groups, R 1 is the same or different and represents monovalent aromatic hydrocarbon radicals containing at least one phenolic hydroxyl group, a is 2 or 3, b is an integer from 1 to 10, c is 2 or 3, d is 1 or 2, with the proviso that per poly(diorgano)siloxane molecule of the general formula (I) one or two radicals R 1 are present.

2. Poly(diorgano)siloxane according to claim 1, which has a weight-average molecular weight Mw of 300 to 2000 g / mol and / or which has a number-average molecular weight Mn of 300 to 1500 g / mol.

3. Poly (diorgano)siloxane according to one of the preceding Claims, which has a PDI in the range of 0.8 to 1.

5.

4. Poly (diorgano)siloxane according to one of the preceding Claims, wherein R is selected from the group consisting of - Alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, neo-pentyl, 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 2,4,4-trimethylpentyl and the 2,2,4-trimethylpentyl 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; - Hexadecyl radicals, such as the n-hexadecyl radical; - octadecyl radicals, such as the n-octadecyl radical; - cycloalkyl radicals, such as the cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl radicals; - alkenyl radicals, such as vinyl, allyl, cyclopentenyl and cyclohexenyl radicals; - epoxy residues, such as the 3-glycidoxypropyl, oxiran-2-yl and 2-(3,4-epoxycyclohexyl)ethyl residue; - Aryl radicals, such as the phenyl, biphenyl, cumylphenyl, benzylphenyl, naphthyl, anthryl and phenanthryl radical; - alkaryl residues, such as tolyl, xylyl and ethylphenyl residues; - aralkyl radicals, such as the benzyl, cumyl, a- and b-phenylethyl radicals; - alkoxyaryl residues, such as the methoxyphenyl residue; - aryloxyaryl residues, such as the phenyloxyphenyl residue; - halogenaryl radicals, such as fluorophenyl, chlorophenyl, bromophenyl and trifluoromethylphenyl radicals; and - heterocyclic aromatic hydrocarbon residues, such as pyridyl, pyrazinyl, quinolinyl, furyl residues and the (9,10-dihydro-9-oxa-10-phosphaphenanthren-10-oxid-10-yl)ethyl residue.

5. Poly(diorgano)siloxane according to one of the preceding claims, wherein R is a monovalent, SiC-bonded alkyl radical having 1 to 8 carbon atoms or an aryl radical.

6. Poly(diorgano)siloxane according to any one of the preceding claims, wherein R 1 is selected from a compound described by the following formula (II), (II), wherein R 4 , R 5 , R 6 , R 7 and R 8 each independently of each other hydrogen atom, a hydroxy group or an optionally hydroxyl groups, optionally interrupted by at least one heteroatom, with the proviso that in formula (II) at least one radical R 4 , R 5 , R 6 , R 7 or R 8 is or contains a phenolic hydroxy group.

7. Poly(diorgano)siloxane according to any one of the preceding claims, wherein R 1 is selected from the group consisting of hydroxyphenyl [-CeHa(OH)]-, hydroxy (methyl)phenyl [-CeHa(OH)(CHa)]-, Hydroxy (dimethyl)phenyl [-CeHa(OH)(CHaJa]-, Hydroxy (ethyl)phenyl [-CeHa(OH)(CH2CH3)]-, Hydroxy (methyl)(isopropyl)phenyl [-CeH3(OH)(CH3)(CH (CH3)2)]-, Hydroxy (methoxy)phenyl [-CeHa(OH)(OCH3)]-, Hydroxy (phenyloxy)phenyl [-CeH3(OH)(OCeHs)]-, (hydroxyphenyl)phenyl [-CeHa(CeHa(OH))]-, hydroxynaphthyl [-CioHe(OH)]-, hydroxy (phenyl)phenyl [-CeH3(OH)(CeHs)]-, hydroxy (benzyl)phenyl [-CeHs(OH)(CH2(CeHs))]- and (hydroxycumyl)phenyl [-CeH3(C (CH3)2)(C6H4(OH))] radical, preferably selected from the group consisting of hydroxyphenyl, hydroxy (methyl)phenyl, Hydroxy (dimethyl)phenyl, hydroxy (ethyl)phenyl and Hydroxy (methyl)(iso-propyl)phenyl residue.

8. Poly (diorgano)siloxane according to any one of the preceding Claims which correspond to one of the following formulas (IIIa), (IIIb), (IIIc) and (IV) to (XII) (Illa), (VII) (XI), where R 9 is selected from the group consisting of Me, Ph, Vi, H, (XII), wherein Me is methyl radical, Ph is phenyl radical, m is an integer from 2-11; n is an integer from 1-10 and o is an integer from 1-10, with the proviso that the sum of n + o is equal to 2-11.

9. A process for preparing a poly(diorgano)siloxane according to any one of claims 1-8, comprising the following steps in the order given: (A) Providing an aromatic Hydrocarbon compound according to the chemical formula (XIII) Fh-x (XIII), where R 1 a monovalent aromatic compound containing at least one phenolic hydroxy group hydrocarbon residue, and X represents F, CI, Br or I; (B) protecting the at least one phenolic hydroxy group in R1-X via a suitable protecting group; (C) converting the protected compound R1-X obtained after step (B) into a metal organyl R1-M, where M is preferably Li, Mg-X or Zn-X, in particular Li and Mg-X; (D) reacting the organometallic compound obtained after step (C) with a siloxane according to chemical formula (XIV) R aY3-aSi-O-(RdY2-dSi-O-)b-SiR c Y 3-c (XIV), wherein R is the same or different and - monovalent, SiC-bonded aliphatic hydrocarbon residues, or - monovalent, SiC-bonded, aromatic hydrocarbon radicals free of phenolic OH groups, Y is the same or different and CI, MeO, EtO or OiPr, a is 2 or 3, b is an integer from 1 to 10, c is 2 or 3, d is 1 or 2; and (E) deprotecting the protected poly(diorgano)siloxane obtained after step (D) to obtain the poly(diorgano)siloxane according to any one of claims 1-8.

10. The process according to claim 9, wherein the suitable protecting group in step (B) is selected from benzyl, benzyl derivatives, Allyl residues and tetrahydropyran.

11. The process according to claim 9 or 10, wherein the conversion to a metal organyl compound in step (C) is carried out by, in the case where M is Li, reacting R1-X with an organolithium compound; or in the case where M is Mg-X, reacting R1-X with Mg to form a Grignard compound; or in the case where M is Zn-X, reacting R1-X with Zn to form a Zn organyl compound.

12. The process according to any one of claims 9-11, wherein the deprotection in step (E) is carried out hydrogenolytically or acidically.

13. Use of a poly(diorgano)siloxane according to any one of claims 1-8 as a modifier in organic resins, preferably as a toughening modifier, hydrophobizing agent, modifier for improving flame resistance, thermo-oxidative properties, dielectric properties, moisture resistance, chemical resistance and / or processing properties.

14. Use according to claim 13, wherein the resin is selected from epoxy resins, cyanate ester resins, novolak resins, phenolic resins, UP resins, vinyl ester resins and BT resins.

Images