EP2906568A1

EP2906568A1 - Method for converting reactive groups of si-c-bound groups of silanes while simultaneously increasing the physical distance between said groups

Info

Publication number: EP2906568A1
Application number: EP13776478.3A
Authority: EP
Inventors: Herbert Wolter; Somchith Nique
Original assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Current assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Priority date: 2012-10-11
Filing date: 2013-10-11
Publication date: 2015-08-19
Also published as: WO2014057095A1; US20150274862A1; DE102012109685A1

Abstract

The invention relates to a method for converting reactive groups of Si-C-bound groups of silanes or siloxanes while simultaneously increasing the physical distance between said groups. The Si-C-bound groups have the grouping -AW(Z)_a, where A represents a coupling group selected from -S-, -NH-, and NR³, R³representing an unsubstituted or substituted hydrocarbon group or a (meth)acryl group; W is a substituted or unsubstituted hydrocarbon group, the chain of which can be broken by one or more groups of -S-, -O-, -NH-, -NR³-, -C(O)O-, -NHC(O)-, -C(O)NH-, -NHC(O)O-, -C(O)NHC(O)-, -NHC(O)NH-, -S(O)-, -C(S)O-, -C(S)NH-, -NHC(S)-, and -NHC(S)O-, R³ having the aforementioned meaning; Z represents a functional group which can be the same or different and is selected from OH, the carboxylic acid group -COOH, or a salt or an ester of said group; and a = 2, 3, 4, 5 or a greater number. The invention is characterized in that, in a single or a second reaction, said groups of the silanes or siloxanes are either reacted with a compound (II) Y-(W)_k-(Q)_b (II), where Y is NCO, epoxy, or, if the groups Z are hydroxy groups, COA', A' representing hydroxy, a halide, or -OC(O)R⁴,in which R⁴ is an unsubstituted or substituted hydrocarbon group; W has the aforementioned meaning; Q is either R¹ or OH, NR⁷ ₂, NR⁷ ₃₊ CO₂H, SO₃H, PO(OH)₂, (O)PO(OH)₂, (O)PO(OR⁴)₂,or a salt or an ester of the aforementioned acids, wherein R¹ is an unsaturated, organically polymerizable group, R⁴ has the aforementioned meaning, and R⁷ has either the same meaning as R⁴or two groups of R⁷ together can represent an optionally substituted, optionally unsaturated alkylene group; k = 0 or 1, where k = 0 only in the event that Y represents COA'; and b = 1, 2, 3, 4 or a greater number; or, in the event that Z = OH, the groups of the silanes or siloxanes are reacted with P₂O₅ or POCI₃. The invention further relates to a method for producing silanes or siloxanes with the grouping -AW(Z)_aand to multiple methods which have additional method steps on the basis of the aforementioned single or second reaction, the physical distance between the groups Q being increasable and the number thereof optionally being increasable by means of said method steps. Furthermore, the invention relates to silanes and silicic acid (hetero)polycondensates which can be produced using said methods.

Description

Process for the conversion of reactive groups to Si-C-bonded residues of silanes while increasing their spatial distance from each other

The present invention relates to a process for the conversion of reactive groups to residues of silanes or siloxanes bonded via silicon to carbon and containing at least two reactive groups per radical. It is an object of the invention to increase the spatial distance of these groups to one another and, if necessary, to convert them into other reactive groups. In specific embodiments of the invention, the method is intended to introduce additional functional groups, optionally with the introduction of branches. Repeating individual steps of the process with the introduction of variable functionalities and branching of the chains, this can be a variety of different, partly dendrimerartiger compounds with different organic crosslinking potential and connection length, different polarity, refractive index and etching and

Complexation obtained.

In the field of dental materials, but not only there, it is important to be able to provide a range of materials which, while basically capable of being used for the same purpose and having the same physical and mechanical properties, these properties are specific, often even individual

Requirements must be adjusted in detail. Examples are the color or

Translucence of crowns, matrix hydrophilicity, shrinkage, reactivity with substrates or other matrix or composite components such as tooth tissue, co-reactants or reaction partners in ionomer composites. Here are minimal

Changes often have a big impact. If the specialist working with these materials, such as a dentist or a dental technician, can access a graded range of materials required for his purpose, he will be able to select the right material for each application.

In the past 20 years, a variety of silanes has been developed, which are not only hydrolytically condensable, but, for example via reactive double bonds, in addition to an organic polymerization can be subjected. Over a

Polymerization of existing double bonds and the implementation of any other reactive groups present can be a variety of condensates, polymers and composites made from or with these silanes, which are suitable for a variety of applications.

Examples of such materials are disclosed in DE 40 11 044 A1, DE 44 16 857 C1, DE199 10 895 A1 and DE 196 27 198 A1. However, in these materials, the spatial distance of the various functional groups in the silanes is still relatively low and they are close to the molecular nucleus. The object of the invention is to remedy this situation and to provide methods by which these functional groups, via a carbon-containing chain and a

Carbon atom of this chain are bonded to silicon, while simultaneously converting the functionality into a position that increases the spatial distance of these groups to each other. Due to the structural arrangement of these chains and such displacements, a variety of different resins consisting of silanes and

Silica polycondensates (which can also be referred to as siloxanes or "ORMOCER®e") are available, with different organic crosslinking potential and

Connection length are made. In addition, by reactivating the reactive groups, a variety of resins with variable functionalities can be obtained. In a specific embodiment, it is preferable to increase the number of functional groups present. A larger number of e.g. Hydroxy groups or

Acid groups can positively enhance the matrix hydrophilicity or other properties of the condensates, polymers and composites made from the silanes. In addition, one can thereby achieve that the repeated execution of the branching reactions at the same time a dendrimerartige structure is formed on the carbonaceous radical.

In a solution of the problem, the present invention proposes a method for

Conversion of reactive groups on Si-C-bonded residues of silanes or siloxanes with simultaneous increase in the spatial distance of these groups to each other, wherein the Si-C-bonded radicals the grouping

-AW (Z) _a

have, wherein

A represents a coupling group which is selected from -S-, -NH- and NR ³ , wherein R ^{3 is} (meth) acrylic or a straight-chain, branched or cyclic, unsubstituted or substituted hydrocarbon radical, for example alkyl, aryl, arylalkyl or alkylaryl, and preferably is an alkyl radical, more preferably one to six carbon atoms,

W is a straight-chain, branched or cyclic, substituted or unsubstituted

Is hydrogen radical, for example an alkylene, an arylene, an arylalkylene or an alkylarylene radical or an alkenylene radical, the chain of which may be interrupted by one or more groups -S-, -O-, -NH-, -NR ³ -, -C (O) O-, -NHC (O) -, -C (O) NH-, -NHC (O) O-,

-C (O) NHC (O) -, -NHC (0) NH-, -S (O) -, -C (S) O-, -C (S) NH-, -NHC (S) -, - NHC (S) O-, where R ^{3 has} the above meaning,

Z represents a functional group which may be the same or different and is selected from OH, the carboxylic acid radical -COOH or a salt or an ester of this radical, and

a = 2, 3, 4, 5 or a larger integer, where a = 2 or 3 is preferred and a = 2 is particularly preferred, characterized in that said radicals of the silane or siloxane are reacted in a single or second reaction either with a compound (II)

Y- (W) _k - (Q) _b (II)

wherein Y is NGO, epoxy or - when the radicals Z are hydroxy groups - COA 'wherein A' is hydroxy, a halide or -OC (0) R ⁴ , and R ^{4 is} an unsubstituted or substituted hydrocarbon radical, for example alkyl, aryl, arylalkyl or Alkylaryl, and preferably an alkyl group with more preferably one to six carbon atoms,

W has the meaning given above,

Q is either R ¹ or OH, NR ⁷ _2, NR ⁷ ₃ ^+, C0 ₂ H, S0 ₃ H, PO (OH) _2, PO (OR ⁴⁾ ₂ (0) PO (OH) ₂ (0) PO (OR) ₂ or a salt of the abovementioned acids, where R ^{1 is} an unsaturated, organically polymerisable group and R ^{4 has} the abovementioned meaning, R ^{7 has} either the same meaning as R ⁴ or two radicals R ⁷ together optionally ( hetero) substituted, if necessary

unsaturated, optionally aromatic hydrocarbon group, e.g. an alkylene group, with the proviso that Q in the case of b> 1 in the compound (II) may have different meanings,

k = 0 or 1, where k = 0 is possible only in the case where Y is COA ', and

b = 1, 2, 3, 4 or a larger number, preferably 1, 2 or 3,

or, in the case Z = OH, be reacted with P ₂ 0 ₅ or POCl ₃ .

In the event that two radicals R ⁷ together form a hetero-substituted aromatic

Hydrocarbon group, NR ⁷ ₂ and NR ⁷ ₃ ^{+ may be,} for example, a pyridine radical or the radical of a cyclic ammonium compound or a pyridinium derivative or the like. Residues Q with the meaning NR ⁷ ₂ or NR ⁷ ₃ ⁺ can have important additional functions in a resin produced according to the invention. Thus, in the case of Q, NR ⁷ ₂ is formed

Activator molecule that can be used for a redox cure as mentioned above. Compounds or resins with NR ⁷ ₃ ⁺ radicals have an antimicrobial effect.

The invention is generally based on structures of the following formula (2):

In this formula, the zigzag line represents the backbone of a hydrocarbon radical bonded to the silicon via a carbon atom, which backbone may optionally be branched and may be interrupted as desired by heteroatoms or coupling groups or other heteroatom-containing groups. Examples are: -S-, -O-, -NH-, -C (O) O-, -NHCH (O) -, -C (O) NH-, and the like. Since for the purposes of the invention, the structure of the backbone of this remainder does not matter, the skilled person can make any choice in this regard. The hydrocarbon radical is, apart from the grouping AW (Z) _a, free of functional groups, the expression "functional groups" in particular unsaturated, organically polymerizable groups, carboxylic acids or their metal salts or ester-containing groups (with the formula COOR ° where R ° = unsubstituted or substituted hydrocarbon radical or M * ^ wherein M ^{x +} hydrogen or an x-fold positively charged

Metal cation), radicals of the formula - (0) _b P (0) (R ^* ) ₂ with b = 0 or 1 and R ^* = unsubstituted or substituted hydrocarbon radical which is bonded directly or via an oxygen bridge to the phosphorus atom, and hydroxy groups should include. A, W, Z and a have the meanings given above.

The three unspecified bonds of the Si atom are, if the structure (2) represents a silane, for further bonded to the silicon atom radicals. Instead, they can symbolize oxygen bridges to other silicon atoms or other metal atoms, if the structure (2) is part of a silicic acid (hetero) polycondensate. (The expression

"(Hetero) polycondensate" means that the condensate other than silicon other

Metal atoms of co-condensed compounds may have, for example, B, Al, Ti, Zn and / or other transition metal.) Since the reactions according to the invention can be carried out both on monomeric silanes and on already inorganically crosslinked silicic acid polycondensates, it does not depend on the nature of this bond , In the case of monomeric silanes, these radicals can be hydrolyzable groups, for example under hydrolysis conditions, as known to the person skilled in the art, for example halides or alkoxides. Instead, one or more of these groups can mean OH. In other embodiments, at least one residue of the bond symbolizes at least one other via carbon on the

Silicon atom-bound radical, which may have any properties. These may be those of the above, bonded via a carbon atom to the silicon

Hydrocarbon radicals differ; alternatively, one or even two such radicals may have the meaning of this hydrocarbon radical. The index m indicates that the structure has m silyl groups and is usually 1 or 2, but may optionally also have higher values such as 3, 4 or even greater. Frequently m is 1. A restriction upwards is theoretically not given. If the structure has more than one silyl radical, the second and possibly further silyl radicals are located on the backbone of the structure, which

Accordingly, it must be branched in these cases. In connection with an unsaturated, organically polymerisable group in the present invention under the attribute "polymerizable" or the corresponding

Noun "polymerization" are understood to be a polyreaction in which the reactive double bond under the influence of heat, light, ionizing radiation or

redox-induced (e.g., with an initiator (peroxide or the like) and an activator (amine or the like)) into a polymer (English: addition polymerization or chain-growth polymerization).

There are no cleavages of molecular components, nor migrations or rearrangements. Examples of unsaturated, organically polymerizable groups are therefore non-aromatic C =C double bonds, preferably double bonds accessible to Michael addition, such as Styryle or (meth) acrylic acid derivatives. Each unsaturated, organically polymerizable group generally contains at least two and preferably up to about 50, but possibly also more carbon atoms and may be bound directly or via a coupling group to the carbon skeleton of the hydrocarbon-containing radical.

The term "(meth) acrylic ..." shall mean in the present case that they are each the

corresponding acrylic or the corresponding methacrylic compound can act.

The present (M et h) Acry I sow u Re-derivatives include the acids themselves, optionally in activated form, esters, amides, thioesters and the like. In the reaction according to the invention, the silane or silicic acid polycondensate for the purpose of converting the reactive Groups and simultaneous increase in the spatial distance of these groups to each other with the above-mentioned compound of formula (II) or in certain cases with P ₂ 0 ₅ or POCI ₃ reacted.

By the reaction according to the invention with compound (II), the radical AW (Z) _a on the Si-C-bonded radical of the silane or silicic acid polycondensate having the structure (2) via a coupling group B is further - (W) _k - (Q. ) b attached. The coupling group B arises from the attack of Y on Z and can therefore be selected from ester, ether, acid amide and urethane groups. si] ^ AW (Z) _a + Y- (W) _k - (Q) _b - {si] ^ AW (B (W) _k (Q) _b ) _a (2) (II) (3)

Since the compound (II) can carry a plurality of optionally independent radicals Q, the number of functional groups per Si-C bonded radical can be increased and varied, and a dendrimer-like structure can be applied.

In this - as well as all the below-described reaction (s), it is advantageous if the compound of formula (II) is used in a molar Unters chuss, based on the functional groups of the reactant, here the structure (2), if so the molar ratio of the compound (II) to that of the functional groups Z on the Si-C bonded radicals is <1, and is preferably at most 0.95.

This technical teaching is based on the finding that when compound (II) is used in deficit, this compound is completely consumed, so that in the materials to which the product of this reaction is processed, there are no longer any problematic monomers from a toxicological or allergological point of view are. In addition, it has It was found to be irrelevant that all functional groups would have to be fully implemented, because a more or less large proportion of non-extended Si-C-bound residues in the mixture does not adversely affect the properties of the latter. And finally, there is a decisive advantage for further possible reactions: the product of the reaction need not be purified or worked up in any other way and can therefore be subjected to a subsequent reaction immediately and inexpensively, as is preferred for the present invention.

Preferably, for the single or second reaction of the invention, a compound in which QR is ¹ is used as compound (II). As a result, a C =C double bond-containing group is introduced into the Si-C-bonded radical via the coupling group B at the location of the groups Z, the distance between the C =C double bonds being greater than the distance between the previously present Z groups ,

In a further preferred embodiment, which may be linked to or independent of the above embodiment, Z in the compound or the condensate having the structure (2) is OH and is reacted with a compound (II) in which Y is the Isocyanate group. This creates a urethane group as linking group B

The product of the reaction according to the invention is therefore a compound or a condensate having modified functional groups and moreover usually having at least one radical Q on a Si-C-bonded hydrocarbon radical, wherein the radical or radicals Q, however, in relation to the radical Z in the structure ( 2) have a distance to the silicon atom, which is extended by BW- by this reaction. Because of the plurality of relatively long chains over relatively long movable double bonds, which are located substantially in the outer region of the silane molecule or the siloxane and thereby a relatively large spatial

Having a distance from one another, this can lead to a reduction in the shrinkage during subsequent crosslinking, which can be of great advantage, in particular in the dental field, and, on the other hand, to increased strength and reduced brittleness. In addition, the Si-C-bonded hydrocarbon radical may optionally have additional functionalities, if e.g. not all of the hydroxy groups of the structure of formula (2) are stoichiometrically reacted (i.e., when compound (II) is used in deficit) and / or

Use of a compound of the formula (II) which, in addition to an unsaturated, organically polymerisable group, has further, independent functionalities.

The reaction described above will be explained below with reference to two examples: First example:

The two hydroxyl groups (groups Z of structure (2)) serve as the point of attack of the compound (II) isocyanate-methacrylate. Therefore, a branched silyl-methacrylate compound of structure (3) is formed, in which the two methacrylate groups have been displaced outwards relative to the hydroxy groups of structure (2) by the group H ₄ C ₂ -NH-C (O) and thus one have greater spatial distance from each other. The product (3) obtained in this reaction has a very high strength at significantly reduced

Brittleness and a significantly reduced hardness shrinkage. In this example, as explained above, a deficiency of compound (II) can be used with respect to the two hydroxy groups, so that not both hydroxy groups of the

Starting material to be fully implemented. Depending on the amount of compound (II) used, which may be up to 2 molar equivalents, arises either a mixture with only partially reacted secondary hydroxy groups or a branched Si-C-bonded radical with two methacrylate groups. Due to this fact, a finely graded spectrum of products with strong but differently improved physical properties such as breaking strength, modulus of elasticity or deflection can be produced.

Second example of the reaction according to the invention: Instead of a structure whose Si-C-bonded carbon radical carries a thioether group, it is possible to use as structure (2), for example, one having a tertiary amino group which carries two hydroxyl groups. Their reaction with the same isocyanate-methacrylate obeys the following equation:

^ - iCatJ ^' Tea ^,

It can be seen that the C = C double bonds formed are much farther apart and attached to much longer, movable chains.

With regard to the molar ratios, the same applies as described for the first example. The products (3) of the two examples of the invention shown above

Reaction contain as mentioned organic polymerizable C = C double bonds, which were obtained by conversion of hydroxy groups and with respect to these have a greater spatial distance from each other at the Si-C-bonded radical. This is an object of the present invention. In this form they can be reused. In a variant of the invention, which is described in more detail below, they can in turn be used in hydroxy

Functions are converted, which in turn are spatially even further apart and can possibly serve once again the introduction of C = C double bonds. This can be u.a. the spatial distances of the unsaturated, polymerizable groups to each other even further increase. Moreover, at each of the mentioned

Reactions increase the number of reactive groups, making dendrimer-like

Structures are preserved. In a preferred variant of the invention, certain functional groups are introduced by further transformations. In a particularly preferred embodiment, the preceding reaction possibilities are carried out starting from a hydrolyzed / condensed silane. As a result, starting from a single base resin by introducing variable functionalities a variety of different resins with different organic crosslinking potential and connection length can be produced, the different polarity, refractive index, etching and Have complexing behavior. Additional effects that result from the attachment of these functional radicals, in addition to the dendrimerization and the antibacterial effect explained above, the complexing or adhesion properties of eg carboxylic acid, phosphonic acid or phosphoric acid groups, which are extremely improved because of the external seat of the corresponding groups (eg form many effective "grab points").

In a specific embodiment of the invention, silanes or siloxanes having at least two hydroxyl groups on the Si-C-bonded radicals are reacted with phosphorus pentoxide. Subsequent workup with water (see Example 2) both

Hydroxy groups are converted to a phosphoric acid function containing the remainder of the molecule as a monoester group, whereby the product is e.g. be used in aqueous solution as a dental adhesive ka

Of course, the products of this reaction do not contain coupling group B and thus do not fall under the scheme of the compounds (3).

The functional groups present in structure (3) or by reaction with phosphorus pentoxide can in principle be used for various purposes:

(1) The introduction of external C = C double bonds, the enlarged

have spatial distance from each other, leads to a reduced

Hardness shrinkage on cross-linking and very high strength with significantly reduced brittleness after curing.

(2) By introducing aromatic groups, a graded increase in refractive index or

adaptation possible.

(3) Structures with phosphoric acid ester groups make a very water-soluble

Product that can be used as a dental adhesive.

(4) It is possible to use previously introduced organic polymerizable groups,

especially when these are reactive C = C double bonds, others Attach compounds to the Si-C bonded radical. On the one hand, this allows variable functionalities to be introduced into the system. On the other hand, the spatial distance of the corresponding functional groups to each other can be further increased. Thirdly, one or more repetitions of a cycle of functionalization and attachment, while at the same time increasing the

Number of functional groups, dendrimerartige structures obtained.

In a preferred variant of the invention, compounds of structure (2) are prepared in a preceding, first reaction, generally starting from structures of formula (1), i. Silanes and silicic acid (hetero) polycondensates having at least one radical bonded to a silicon atom via a carbon atom, the (at most) one

unsaturated, organically polymerizable group R ¹ carries. For the purpose of converting the unsaturated organic-polymerizable group R ¹ and simultaneously increasing the functionality, they are reacted with a compound of the formula (I) as follows:

(1) (I) (2)

The subscript m and the radical R ¹ have the meanings given above. Simple examples of compounds of the formula (1) are methacryloxyalkyltrialkoxysilanes and also representatives of silanes and polycondensates of silanes (siloxanes), as described in DE 40 1 1044 A1,

DE 44 16 857 C1, DE 196 27 198 A1 or DE 199 10 895 A1 are disclosed. In the compound of the formula (I), X represents SH, NH ₂ or NHR ⁴ , and Z and W and the subscript a are as defined for the compound (2).

In this reaction, the radical X of the compound (I) on the double bond of the group R ¹ attacks and thus extends the hydrocarbon radical of the structure (1) via the coupling group A = -S-, -NH- or -NR ⁴ to the fragment AW , In this case, the radical Z, if it is stoichiometric, is introduced a-fold into the Si-C-bonded radical.

In a preferred embodiment of this first reaction, X in the compound of the formula (I) has the meaning SH. In this variant, the radical -W- (Z) _{a of} the compound of the formula (I) is attached via a thiol-ene addition to the unsaturated, organically polymerizable group R ¹ of the radical bonded to the silicon atom. Alternatively, X can also be NH ₂ or, in another alternative, NHR ⁴ , where R ^{4 has} the above meaning. These radicals also attack on the unsaturated C = C double bond, so that the radical -W- (Z) _{a is} attached to the radical bound to the silicon atom via an NH- or NR ⁴ -bridge. In an independent, preferred embodiment, which can be combined with any of the above-mentioned embodiments, the radical Z in the compound of the formula (I) has the meaning OH or COOH. The meaning Z = OH is particularly preferred, also and in particular in combination with a = 2 or 3, preferably a = 2. The reaction of the silane or silicic acid polycondensate having the structure (1) with the

Compound of the formula (I) is referred to in the context of the present invention as a "first reaction". This will be described below with reference to a number of examples.

The starting material in the first of these examples is structure (1)

Silica polycondensate used by hydrolysis and condensation of a

(Methacryloxymethyl) methylsilans (preferably in the "sol-gel" - method) was prepared (see also Comparative Example 1). This structure is then reacted with a compound of formula (I) wherein X is a mercapto group, Z is hydroxy, W is a saturated hydrocarbon group of three carbon atoms and a = 2:

- Cat

The product of this reaction (Preparation Examples 1a and 1b) contains an Si-C-bonded hydrocarbon radical extended by one sulfur atom and three carbon atoms, in which the original functional group (the C =C double bond) has been replaced by two hydroxy groups. As linking group A, it contains a thioether group.

Of course, instead of the diol used in the example for the compound of the formula (I), it is also possible to use compounds having more than two hydroxyl groups (3 or 3)

optionally 4 or more) as the compound of formula (I). It then structures of the formula (2) with a higher number of hydroxy groups, which in the subsequent reaction with the compound (II), a number of radicals Q can be obtained which when using compounds (II) having two or more radicals Q can be very high. Instead, mixed compounds such as thio alcohols or amino alcohols can be used.

When the first reaction is reacted with a deficiency of compound (I), the product contains not only the structure of the formula (2) but also unreacted material (the structure (1)), see the above example. Incompletely converted materials of this type can be used here in all variants as needed. In this case, a ratio of 0.5 to 0.95 mol of the reagent Z introducing the remainder Z (the compound (I)) is preferably used, in this case preferably 0.5 to 0.95 mol of thioglycerol per mol of C = C double bond used ; instead, of course, the compound of formula (I) can also be used, as needed, to molar equivalence or, in some cases, even more. However, the latter is generally unfavorable in view of the desired avoidance of the presence of monomer residues in the resin.

In another variant of the invention, a compound of the formula (I) is used for the first reaction in which the radicals Z represent carboxylic acid radicals (C0 ₂ H). Also mixed

Compounds are possible, that is those compounds which have both a hydroxy and an acid function.

Instead of a compound of the formula (I) in which X is a mercapto group, this reaction could also be carried out with a compound of the formula (I) in which X is a primary or, less preferably, a secondary amino group containing two or more contains more hydroxy or other Z groups as defined above.

As an example of such a reaction, in a second example of the first reaction, the reaction of a silicic acid polycondensate with a dihydroxy-substituted secondary amine is shown:

Also in this reaction, a may mean not only 2 but instead 3 (or optionally 4 or more).

The difference to the above example lies in the nature of the coupling group (here a tertiary amine instead of a thioether bridge). With regard to the modification of the functional groups in the focus of the invention, the choice of the radical X plays no role, since this is responsible only for the structure of the linking group A between the newly connected radical -W- (Z) _a and the remainder of the molecule few exceptions - has no technical function or effect. One of these exceptions relates to the mercapto group, the use of which as a radical X offers a specific advantage: the incorporation of the sulfur atom as linking group A in the backbone of the Si-C bonded radical causes an increase in the refractive index n _{D of} the resulting silicic acid polycondensate compared to a secondary or tertiary amino group, which can be varied by providing or omitting the thioether group. A second exception concerns basic amino groups that can be protonated. Specific examples of compounds of the formula (I) are: OH-functionalized thiols having two hydroxy groups, such as thioglycerol, C0 ₂ H-functionalized thiols having two carboxylic acid groups, such as mercaptosuccinic acid or 2-sulfanylmethylsuccinic acid.

The first reaction need not necessarily occur on already hydrolytically condensed silanes, as shown above. Instead, it can of course be carried out on monomeric silanes.

In one embodiment of the invention, the product of the (first or only) reaction according to the invention may be the end product, both when the group is QR ¹ , ie an unsaturated, organically polymerizable group, and when Q is OH, NR ⁷ ₂ , NRV, CO ₂ H, SO ₃ H, PO (OH) ₂ , PO (OR ⁴ ) ₂ , (0) PO (OH) ₂ , (0) PO (OR ⁴ ) ₂ or a salt of the abovementioned acids ,

In a second embodiment of the invention, the product of the invention

Reaction of a third and possibly even further reaction (s) subjected. The third reaction can take place in two variants:

In the first variant, the radical Q in the product (3) is an unsaturated organic

polymerizable group (ie R ¹ ). The reaction is carried out analogously to the first reaction with a compound of the formula (III),

(3) (III) (4) wherein X is defined as defined for formula (I), W, Q and b as for formula (II) and A 'is a coupling group formed by the attack of group X of the molecule of formula (III) at C = C Double bond of the organic polymerizable group R ^{1 is} formed. The result is a product in which the number of radicals Q abb (as defined for the indices of the formulas (I) to (III)) corresponds; in other words, instead of each originally-existing unsaturated polymerizable group R ¹ in the structure (1), there are abb residues Q in the structure (4). For example, when a dihydroxy compound was used as the compound of the formula (I) as shown in the above examples, and as the compounds (II) and (III), respectively

Mono (meth) acrylate, the product contains (4) two groups Q as functional radicals in place of any original unsaturated organic polymerizable group on a Si-C-bound radical, which still have a significantly increased distance from each other. Accordingly, in the case that the index b in the compound (II) and / or (III) is greater than 1, namely 2, this number increases to four and eight, respectively. The emergence of dendrimer-like structures is apparent. The radicals R ¹ are moreover in the form of the radicals Q in

Compared to compound (1) pushed by the grouping A-W-B-W-A'-W to the outside.

In the second variant of the third reaction, the radical Q in the product (3) is selected from OH, the carboxylic acid radical -COOH or a salt or an ester of this radical, and the product (3) is reacted with a compound of the formula (II) in which the radicals have the meaning given above for this compound: {si] AW (B (W) _k (Q) _b ) _a + Y- (W) _k - (Q) _b - {si] ^ AW (B (W) _k (B (W) _k (Q) _b ) _b ) _a

(3) (II) (5)

Structure (5) differs from structure (4) only by the replacement of the coupling group A 'with B; for the rest, the above applies. Incidentally, both structures (4) and (5) are comparable to structure (3), but the number of residues Q compared to (3) is still increased by the factor b (due to the reaction with the compound (II) or (III) ) and these radicals are located further away from the Si atom by a group AW or BW. The effects are accordingly increased again compared to those described for (3). This applies in particular to the previously described reduction in the

Shrinkage during subsequent crosslinking and for the material properties strength and brittleness.

The third reaction can in turn be carried out with a molar deficiency of compound (II) or compound (III), based on the radical Q in the structure (3), in order to mix the structures (4) or (5) with To obtain structure (3). In this way, even finer graduated products can be won. In a variant of the invention, the products (4) and (5) are the end products.

However, the products (4) and (5) can then, if Q in turn either a

unsaturated organically polymerisable group R ¹ or is selected from OH, the carboxylic acid radical -COOH or a salt or an ester of this radical, optionally subjected to a fourth reaction, again with a compound of the formula (II) or of the formula ( III), depending on the importance of the radical Q. The reactions proceed analogously to the two variants of the third reaction. This results in this fourth

Reaction Products that can be represented as follows:

(4) (III) (6) †] ^ wAW (B (W) _k (A'W (Q) _b ) _b ) _a + Y- (W) _k - (Q) _b ^ Si ^ AW (B (B) W) _k (A'W (B (W) _k (Q) _b ) _b ) _b ) _a

(4) (Ii) (7) isi ~ AW (B (W) _k (B (W) _k (Q) _b ) _b ) _a + XW- (Q) _b ^ Si ^ AW (B (W) _k ( B (W) _k (A'W (Q) _b ) _b ) _b ) _a

(5) (III) (8)

(5) (II) (9)

Both the starting materials of these reactions and the respective end products can be attributed to the formula (3), wherein the b-fold group Q of the formula (3) has been converted into a b-fold structure D. These products can be therefore, represented by the following formula (A)

{si] ~ AW (B (W) _k (D) _b ) _{a (A)} wherein D is selected from A'W (Q) _b (formula (4)), B (W) _k (Q) _b ( Formula (5)), A'W (A'W (Q) _b ) _b (Formula (6)), A'W (B (W) _k (Q) _b ) _b (Formula (7)), B ( W) _k (A'W (Q) _b ) _b (Formula (8)) and B (W) _k B (W) _k (Q) _b ) _b (Formula (9)). In the products formed by the abovementioned reactions of (5) and (6) with (III) or (II), the radicals Q are present in each case from b-b-fold, and with a further increased distance to the Si atom and increased spatial distance from each other. Incidentally, they differ - with the proviso that in each case comparable residues Q and groups W are used - only by the number and distribution of the

Coupling groups A, A 'and B. The advantages of such dendrimers therefore correspond to those described in product (3), but are again reinforced. An example of such a reaction is the reaction of a structure (4) in which Z is at least partially OH with an isocyanate methacrylate.

The principle of the reaction sequence can basically be continued; there the

Products at least in the cases where X is SH or Y is equal to NGO, and in particular when the compounds (I) to (III) are used in deficiency, based on the respective functional groups, not isolated or purified In this way, structures having a finely graduated number of reactive groups or organically polymerizable radicals Q on each Si-C-bonded radical can be produced, which are dendrimer-like branched. In summary, the invention thus makes it possible, starting from silanes with organically polymerizable double bonds, e.g. C = C-containing silanes such as (methacryloxymethyl) -methyldimethoxysilane (see the examples, the hydrolytically condensed

Silica polycondensate from this silane is referred to therein as base resin system-1) by the reaction with a compound (II) (for example, thioglycerol), and a subsequent

Introduction of C = C groups (eg, methacrylic acid isocyanatoethyl ester) and subsequent hydrolytic condensation with the method according to the invention to obtain a silicic acid polycondensate whose groups Q, for example OH, C0 ₂ H or C = C groups, optionally further functionalized can be. The hydrolytic condensation can, of course, already be carried out at an earlier stage, for example at the stage of the starting material (see base resin system-1) or at the stage of the silane containing at least two groups Z.

If such a product is already at hand, the first step of this reaction sequence need not be performed.

It is preferred to use a hydrolyzed / condensed silane (e.g.

Base resin system I, see the examples) or the corresponding starting silane, if appropriate in combination with other silanes or other hydrolyzable components, such as

To condense alkoxides of aluminum, titanium or the like hydrolytically and then to carry out the subsequent reactions as described above. This route has the advantage that one proceeds in each case from a single base resin (ready hydrolysed / condensed) and by variable proportions of the reactants or their amount of functional groups a variety of different resins with different organic crosslinking potential and compound length (- after curing variable crosslinking density) , different polarity, refractive index, etching u. Complexation behavior in a simple manner (ie usually without work-up step) can produce. The silicic acid polycondensates according to the invention can be cured in various ways. For example, existing C =C double bonds can be crosslinked by polyaddition with thiols or amines or a conventional radical polymerization of the double bond-containing groups (polymerization reaction with formation of propagating carbon chains), which causes hardening of the material. The condensates can also be cured by other crosslinking reactions, for example by reaction with di-, tri- or tetra-isocyanates which attack free carboxylic acid or hydroxyl groups, or corresponding polyfunctional anhydrides for the reaction of hydroxyl-containing condensates, which also another, purely organic network is created.

In the case of crosslinking, properties such as the length of the molecular chains between the crosslinking sites and the remaining proportions of free reactive groups can furthermore be set, for example by adding variable proportions of di-, tri- and / or tetraisocyanates, each with free groups Q can respond. The corresponding

Mono compounds would only lead to an abreaction of the reactive groups and thus to their conversion into an inactive coupling group. If, however, bis-, tris or even higher functional compounds are used as reactants, linkages are generated via bridges of optionally adjustable length (the length is set by the distance between two reactive groups in the molecule). An example of this is the reaction with isocyanates: here, for example, dicyclohexylmethane diisocyanate, hexamethylene-1,6-diisocyanate, hexamethylene-1,8-diisocyanate, diphenylmethane-4,4-diisocyanate, diphenylmethane-2,4-diisocyanate, 2,4- Toluene diisocyanate, 2,6-tolylene diisocyanate, triphenylmethane-4,4 ^' , 4 ^" -triisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl-diisocyanate, or tris (p-isocyanato-phenyl) -thiophosphate or polysiloxane free

Has hydroxyl groups (eg in the case of Q at least partially = OH), such crosslinking may also be carried out with a di-, tri-, tetra or polyfunctional, optionally activated (eg present in the form of an anhydride) carboxylic acid parts of the di-, tri- or tetrapolyisocyanate, and if the silane or polysiloxane free carboxylic acid radicals, their salts or esters, with a di-, tri-, tetra or polyfunctional alcohol. The curing of resins in which the group is QR ¹ , ie an unsaturated, organically polymerizable group such as a C = C-containing group, can be influenced by additives. Examples are variable proportions of di-, tri, tetra-amines which can react with reactive C =C double bonds and thus, for example, with (meth) acrylate groups. In addition to crosslinking by light-induced organic polyaddition, crosslinking can occur here through polyfunctional amines. Examples of polyfunctional amines are:

Diaminoacetone, diaminoacridine, diaminoadamantane, diaminoanthraquinone, benzidine,

Diaminobenzoic acid, phenylenediamine, diaminobenzophenone, diaminobutane, Diaminocyclohexane, diaminodecane, diaminodicyclohexylmethane, diaminomethoxybiphenyl, diaminodimethylhexane, diaminodiphenylmethane, diamino-dodecane, diaminoheptane,

Diaminomesitylene, diaminomethylpentane, diaminomethylpropane, naphthylendiamine,

Diaminoneopentane, diaminooctane, diaminopentane, diaminophenanthrene, diaminopropane, diaminopropanol, diaminopurine, diaminopyrimidine.

The same succeeds if thiols are used instead of the amines described above. Examples of multifunctional thiols are: trimethylolpropane tri (3-mercaptopropionate) (TMPMP);

Trimethylolpropane-trimercaptoacetate) (TMPMA); Pentaerythritol tetra (3-mercaptopropionate) (PETMP); Pentaerythritol tetramercaptoacetate) (PETMA); glycol dimercaptoacetate; Glykoldi (3-mercapto-propionate); Ethoxylated trimethylolpropane tri (3-mercaptopropionate); Biphenyl-4-4 ^'- dithiol; p-terphenyl-4,4 ^"dithiole, 4,4 ^{'-Thiobisbezenthiol;} ^4,4' -Dimercaptostilben; benzene-1, 3-dithiol, benzene-1, 2-dithiol, benzene-1, 4-dithiol; 1 , 2-benzene dimethanethiol; 1, 3-benzene dimethanethiol; 1, 4-benzene dimethanethiol; 2,2 ^' - (ethylenedioxy) diethanethiol; 1, 6-hexanedithiol; 1, 8-octanedithiol; 1,9-nonanedithiol Resin systems (ie, the silicic acid polycondensates) of the present invention or their cured products can be used for a variety of applications including, but not limited to, dental, preferably direct / indirect restorations, prophylaxis (eg, fissure sealing), dental adhesives, prosthetics, and dentures.

The invention will be explained in more detail below with reference to concrete reaction examples.

The curing of the resins is effected in each case by adding the resin with 1 wt .-% Lucirin TPO in a rod shape (2 x 2 x 25 mm ³ ). The (eth) acrylate groups are reacted as part of a photoinduced radical polymerization, whereby the resin hardens. By means of a 3-point bending test, the modulus of elasticity, the breaking strength and the deflection up to the breakage of the resulting rods are determined after storage for 1, 5 days at 40 ° C. The shrinkage values are obtained by buoyancy method in the context of photoinduced radical polymerization (15 min after exposure).

Comparative Example 1 (Synthesis of the base resin system I):

Hydrolysis / condensation of (methacryloxymethyl) methyldimethoxysilane:

61, 3 g (0.30 mol) of (methacryloxymethyl) -methyldimethoxysilane are dissolved in ethyl acetate (1000 ml / mol of silane) and stirred after addition of H ₂ 0 for hydrolysis with HCl as cat. At 30 ° C. The course of the hydrolysis is followed in each case by water titration. The work-up is carried out after about 2 days of stirring by repeated shaking with aqueous NaOH and with water and filtration through hydrophobic filter. It is first spun off and then withdrawn with oil pump vacuum. The result is a liquid resin without the use of reactive Thinners (monomers) with a very low viscosity of approx. 38 mPa · s at 25 ° C. The resin is cured as explained above.

Mechanical data:

• bending strength = 48 MPa; Modulus of elasticity = 2.6 GPa

o Very low strength with high brittleness

Hardness shrinkage: 7.1% by volume (15 minutes after exposure)

o High hardness shrinkage

Refractive index = 1, 465

Preparative Example 1a (Preparation of the Grouping -AW (Z) _a on the Structure according to the First of the Examples presented above with a 5% deficit of thioglycerol (a = 0.05):

5.12 g (0.048 mol) of thioglycerol (3-mercaptopropan-1, 2-diol) are added dropwise with stirring to 7.92 g (0.05 mol) of base resin system I and optionally 0.10 g of triethylamine. The reaction can be monitored by NMR as well as by the decrease of the HS band by Raman spectroscopy. The characteristic of the HS group band appears in

Raman spectrum at 2568 cm ^-1, resulting in a liquid resin, further workup is generally not required.

Production Example 1 b (preparation of the grouping -AW (Z) _a as in Preparation Example 1a, but with a 50% deficit of thioglycerol (a = 0.50): To initially charge 19.0 g (0.12 mol) of Base resin system I and optionally 0.12 g of triethylamine are added dropwise with stirring 6.49 g (0.06 mol) of thioglycerol (3-mercaptopropane-1, 2-diol) to give a liquid resin having a viscosity of about 2, 8 Pa s at 25 ° C (depending on the exact synthesis and work-up conditions of the precursor) Further work-up is usually not required · The refractive index of this product is finely adjustable via the thiol content (a slight increase is observed over the base heiz system I, with the thiol content of this example, it increases to 1, 482)

• The polarity / hydrophilicity is adjustable via the OH content, which exceeds the

Thiol compound as introduced herein via the thioglycerol (i.e., a strong, graded increase compared to the base resin system I)

Example 1 a: Preparation of a polysiloxane of structure (3) with Q = organically polymerisable group (methacrylate group) using the product from Preparation Example 1 a 2.72 g of a reaction mixture of base resin system I and Example 1a (molar ratio = 1: 0.95) 2.79 g (0.0224 mol) of isocyanatoethyl methacrylate are added dropwise under a dry atmosphere at 30 ° C with stirring and at 30 ° C stirred. The reaction can be monitored by the decrease of the OCN band by IR spectrum. The characteristic band for the OCN group appears in the IR spectrum at 2272 cm ^-1, resulting in a liquid resin having a viscosity of about 2500 Pa s at 25 ° C.

Example 1 b: Preparation of a polysiloxane of structure (3) with Q = organically polymerisable group (methacrylate group) using Production Example 1b

To prepare 19.2 g of a reaction mixture of base resin system I and Example 1 b (molar ratio = 1: 0.50) under dry atmosphere at 30 ° C with stirring

19.96 g (0.090 mol) of isocyanatoethyl methacrylate are added dropwise and the mixture is stirred at 30 ° C. The result is a liquid resin having a viscosity of about 2700 Pa s at 25 °. Subsequently, the resin is cured.

• bending strength = 135 MPa; Modulus of elasticity = 3.2 GPa

o Very high strength with significantly reduced brittleness (compared to

underlying base resin system-I)

Hardness shrinkage (comparison): 5.8% by volume (15 minutes after exposure)

o Significantly reduced hardness shrinkage (compared to the underlying base resin system I)

Table 1

From the example can thus be seen that on a single material basis

Chain branching a generally very broad modulus of elasticity is adjustable and significantly improved mechanical data (increased strength, reduced brittleness) compared to the underlying base resin (prior art) are observed. The systems can be implemented without the use of dental monomers, which is essential in view of the increasing allergy discussion in the dental field. The invention further enables additional functionalization via the introduction of further OH groups or other groups. The product thus obtained has a low shrinkage value. Comparative Example 2 Synthesis of the Base Resin System II

To prepare 41.2 g (0.2 mol) of [3- (2-aminoethylamino) propyl] methyldimethoxysilane and 50.6 g of triethylamine in 200 ml of anhydrous toluene, 43.9 g (0.42 mol) of methacryloyl chloride are added at a temperature added dropwise from 5-10 ° C and then stirred at 23 ° C for about 18 h. The precipitate is filtered off and the filtrate is washed twice with 150 ml of water. After adding 20.5 mg of BHT (4-hydroxy-3,5-di-tert-butyltoluene), the solvent is removed under reduced pressure to obtain a viscous resin. Further workup is usually not required. The resin dissolved in 200 ml of ethyl acetate is hydrolyzed at 30 ° C. after addition of dilute hydrochloric acid. The work-up is carried out after about 2 days stirring by repeated shaking with aqueous NaOH solution or water and filtration through hydrophobic filters. After removing the solvent under reduced pressure, a high-viscosity resin is obtained.

Production Example 2

First, 14.8 g (0.05 mol) of base resin system II and 5.4 g (0.05 mol) of thioglycerol are dissolved in 20 ml of toluene at 85 ° C. After adding about 1 ml of 1, 8-diazabicyclo [5.4.0] undec-7-ene as a catalyst for the thiol addition, the reaction mixture is further heated with stirring for about 6 h. The reaction can be monitored by NMR spectroscopy on the decrease of the C = C double bond. After removing the solvent under reduced pressure, a high-viscosity resin is obtained. Further workup is usually not required. The ratio of methacrylic groups to thiol groups in this example is 2: 1, which is why the thiol-en addition occurs essentially exclusively on the methacrylic group bonded via a secondary amino group which is preferred for the reaction, and the tertiary-bonded methacrylic group remains unreacted.

Example 2: Preparation of a polysiloxane with phosphoric acid functions 8.08 g (0.02 mol) of resin from Preparation Example 2 are suspended in 30 ml of anhydrous methylene chloride and 14.2 g (0.1 mol) of P ₂ O _{5 are} added in portions. The

Reaction mixture is stirred for about 18 h at 23 ° C. Subsequently, 50 ml of water are added and stirred at 23 ° C for a further 24 h. After removal of the solvent, a highly viscous, water-soluble product is obtained. From the ³¹ P spectrum (Figure 1) results in the reaction with P ₂ 0 ₅ to form the desired Phosphorsäurealkylester.

Comparative Example 3 Synthesis of the Base Resin System III

43.7 g (0.20 mol) (acryloxypropyl) -methyldimethoxysilane are dissolved in 200 ml of ethyl acetate and stirred after addition of H ₂ 0 for hydrolysis with HCl as a catalyst at 30 ° C. The course of the hydrolysis is followed in each case by water titration. The work-up is carried out after about 2 days of stirring by shaking out with water and filtration through a hydrophobic filter. The solvent is first removed by rotary evaporation and then drawn off with an oil pump vacuum. The result is a liquid resin without the use of reactive diluents (monomers) with a very low viscosity of about 85 mPa · s at 25 ° C. This resin is cured as explained above.

Mechanical comparison data:

Flexural strength = 37 MPa; Modulus of elasticity = 1, 3 GPa

o - »Very low strength with high brittleness

Curing shrinkage: 7.5% by volume (15 minutes after exposure)

o -> high hardening shrinkage

Production Example 3

To prepare 19.0 g (0.1 1 mol) of base resin system III with stirring 9.83 g (0.0935 mol = 85 mol%, based on the number of acrylate groups of the base resin system, ie α = 0.15 ) Diethanolamine was added dropwise and stirred at RT for about 1 day. The implementation may u. a. Mitteis NMR be followed by the decrease of the acrylate group. The result is a liquid resin without the use of reactive diluents (monomers) having a viscosity of about 12 Pa s at 25 ° C. Further workup is usually not required.

Example 3: Preparation of a polysiloxane of structure (3) with Q = organically polymerizable

Group (methacrylate group) from the product of Preparation Example 3

To prepare 18.3 g of resin from Preparation Example 3 (0.07 mol) are under dry atmosphere at 30 ° C with stirring 17.9 g (0, 116 mol, 195 mol%, based on the

Diethanolamine residue or 97 mol%, based on the hydroxyl groups of the resin)

Isocyanatoethyl methacrylate is added dropwise and stirring is continued at 30 ° C. The reaction can be monitored by the decrease of the OCN band by IR spectrum. The for the OCN Group characteristic band appears in the IR spectrum at 2273 cm ^-1 resulting in a liquid resin having a viscosity of about 97 Pa s at 25X The resin is cured as explained above.

Mechanical data:

Bending strength = 1 14 MPa; Modulus of elasticity = 2.3 GPa

o Very high strength with significantly reduced brittleness compared to the underlying base resin system-II

o Cure shrinkage: 4.8% by volume (15 minutes after exposure) - »Significantly reduced cure shrinkage compared to the underlying base resin system III

Comparative Example 4 Synthesis of the Base Resin System IV

141, 4 g (0.60 mol) of (methacryloxypropyl) methyldimethoxysilane are dissolved in ethyl acetate (1000 ml / mol of silane) and stirred after addition of H ₂ 0 for hydrolysis with HCl as a catalyst at 30 ° C. The course of the hydrolysis is followed in each case by water titration. The work-up is carried out after about 2 days of stirring by repeated shaking with water and filtration through hydrophobic filter. The solvent is first removed by rotary evaporation and then drawn off with an oil pump vacuum. The result is a liquid resin without the use of

Reactive diluents (monomers) with very low viscosity of approx. 62 mPa · s at 25 ° C. Further workup is usually not required (if necessary, oil pump vacuum is applied for drying). This resin is cured as explained above.

Mechanical comparative data: bending strength «67 MPa; Modulus «1, 63 GPa -> Low strength

Cure shrinkage (comparison): 7.2% by volume (15 minutes after exposure)

-> High cure shrinkage

Production example 4

Production Example 4a: α = 0.5

To prepare 45.5 g (0.24 mol) of base resin system IV and, if appropriate, about 0.29 g of triethylamine, 13.0 g (0.12 mol) of thioglycerol (3-mercaptopropane-1, 2- diol) is added dropwise.

The reaction can be monitored by means of NMR as well as by the decrease of the characteristic HS band (2568 cm ^-1 ) by means of Raman spectroscopy to give a liquid resin, a further work-up is generally not necessary (if necessary oil pump vacuum for drying).

Production Example 4b: α = 0.95

The synthesis is analogous to Preparation 4a, but with a proportion of about 0.23 mol of thioglycerol, which also results in a liquid resin. Further workup is usually not required (if necessary, oil pump vacuum is applied for drying).

Example 4.1: Preparation of a polysiloxane of structure (3) with Q = organically polymerizable group (methacrylic group), which is attached via a urethane coupling group.

Basic reaction principle:

+ / - Cat./ Temp.

In this reaction, the molar fraction of isocyanate can be S 1.

Example 4.1: α = 0.95

To prepare 38.6 g (0.158 mol) of resin from Preparation Example 4a (molar ratio of the silicon atoms in the base resin system IV to thioglycerol = 1: 0.5) under a dry atmosphere at 30 ° C with stirring 23.3 g (0, 95 mol) of isocyanatoethyl methacrylate added dropwise with 0.06 g of BHT (2,6-di-tert-butyl-4-methylphenol) and stirred at 30 ° C (as a catalyst, for example, DBTL = dibutyltin dilaurate can be added, this measure is optional ). The reaction can be monitored by the decrease in the characteristic OCN band at 2272 cm ^-1 in the IR spectrum, resulting in a liquid resin having a viscosity of about 470 Pa · s at 25 ° C. Working up is generally not The resin is cured as explained above.

Mechanical data: bending strength «120 MPa; Modulus of elasticity «2.5 GPa

-> Very high strength and significantly increased modulus of elasticity compared to the underlying base resin system-IV Cure shrinkage: «5, 1 vol .-% (15 min after exposure)

- »Significantly reduced cure shrinkage compared to the underlying

Base resin system IV

Example 4.2: Preparation of a polysiloxane of structure (3) with Q = organically polymerizable group (methacrylic group), which is attached via a carboxylic ester coupling group. O

HO- CH ₂ - CH- _CH2 - S- CH ₂ - CH-C-O-C, H _<r

OH CH ₃

For the example, proportions were chosen which correspond to cc = 0.86 in the above formula.

For the presentation of 26.2 g (0.1 mol) of resin from Example 4a (base resin system IV: thioglycerol = 1 0.5) with dissolved 0.025 g of BHT (2,6-di-tert-butyl-4-methylphenol ) and as catalyst 0, 1 1 g DABCO (1, 4-diazacicyclo [2.2.2] octane) are added dropwise under a dry atmosphere at »65 ° C with stirring 14.65 g (0.095 mol) of methacrylic anhydride u. stirred at 30 ° C under reflux. The reaction can be monitored by means of NMR as well as via the decrease in the anhydride band (1785/1722 cm ^-1 ) by means of an IR spectrum After customary work-up to separate off the methacrylic acid released during the addition and removal of the volatile constituents with oil pump vacuum, a liquid resin results with a viscosity of about 1.6 Pa s at 25 ° C.

Mechanical data: bending strength «84 MPa; Modulus of elasticity * 1, 8 GPa

From the data results in an increased strength and modulus compared to the underlying base resin system IV.

Claims

claims

1. A process for the conversion of reactive groups to Si-C-bonded residues of silanes or siloxanes with simultaneous increase in the spatial distance of these groups to each other, wherein the Si-C-bonded radicals the grouping

-AW (Z) _a

have, wherein

A represents a coupling group which is selected from -S-, -NH- and NR ³ , wherein R ^{3 is} an unsubstituted or substituted hydrocarbon radical or a

(Meth) acrylic group means

W is a substituted or unsubstituted hydrocarbon radical whose chain may be interrupted by one or more groups -S-, -O-, -NH-, -NR ³ -,

-C (O) O-, -NHC (O) -, -C (O) NH-, -NHC (O) O-, -C (O) NHC (O) -, -NHC (O) NH-, -S (O) -, -C (S) O-,

-C (S) NH-, -NHC (S) -, -NHC (S) O-, wherein R ^{3 has} the above meaning,

a = 2, 3, 4, 5 or a larger integer,

characterized in that said radicals of the silane or siloxane are reacted in a single or second reaction either with a compound (II)

Y- (W) _k - (Q) _b (II)

wherein Y is NGO, epoxy or - when the radicals Z are hydroxy groups - COA 'wherein A' is hydroxy, a halide or -OC (O) R ⁴ , wherein R ^{4 is} an unsubstituted or substituted hydrocarbon radical,

W has the meaning given above,

Q is either R ¹ or OH, NR ⁷ ₂ , NR ⁷ ₃ \ CO ₂ H, SO ₃ H, PO (OH) ₂ , (0) PO (OH) ₂ , (0) PO (OR ⁴ ) ₂ or a salt or an ester of the abovementioned acids, where R ^{1 is} an unsaturated, organically polymerizable group and R ^{4 has} the abovementioned meaning, R ^{7 has} either the same meaning as R ⁴ or two radicals R ⁷ together have an optionally

may represent substituted, optionally unsaturated alkylene group,

k = 0 or 1, where k = 0 is only possible in the event that Y is COA ', and b = 1, 2, 3, 4 or a larger number,

or, in the case Z = OH, be reacted with P ₂ 0 ₅ or POCl ₃ .

2. The method of claim 1, wherein the compound of formula (II) is used in an amount such that the molar ratio of this compound to the molar fraction of the groups Z is <1 to 1, and preferably at most 0.95 ,

3. The method of claim 1, wherein in the compound of the formula (II) Y is NGO.

4. The method according to any one of claims 1 to 3, wherein in the compound of formula (II) b = 1 and Q is an unsaturated, organically polymerizable group, in particular a (meth) acrylic acid radical means.

5. A process for the conversion of reactive groups on Si-C-bonded radicals of silanes or siloxanes according to any one of the preceding claims, wherein the Si-C-bonded radicals with the grouping

-AW (Z) _a

are obtained in a first reaction by reaction of Si-C-bonded radicals which carry a maximum of one unsaturated, organically polymerizable group,

with a compound of the formula (I)

X-W- (Z). (I)

wherein

X is SH, NH ₂ or NHR ⁴ and

Z, W and a are as defined in claim 1.

6. The method according to claim 5, wherein in the compound (I) Z is -OH.

A process according to claim 6, wherein in the compound of formula (I) X is SH and a is 2, 3, or 4, preferably 2.

8. The method of claim 6, wherein in the compound of formula (I) X is NHR ¹ and a is 2, 3, or 4, preferably 2.

9. The method according to any one of claims 5 to 8, wherein the reaction with the compound (II) takes place without working up the product from the first reaction.

10. The method according to any one of the preceding claims, wherein in the for the second

Reaction of the compound of the formula (II) Q has the meaning R ¹ , comprising a third reaction with a compound of the formula (III)

XW- (Q) _b (III)

wherein X and W are defined as in formula (I) in claim 5 and Q is as defined for formula (II) in claim 1.

1 1. The method according to any one of Ansprüchel to 9, wherein in the compound used for the second reaction of formula (II) Q is selected from OH, the carboxylic acid residue -COOH and a salt or an ester of this radical, comprising a third reaction with a Compound (II)

Y- (W) _k - (Q) _b (II)

wherein Y, W, Q, k and b are defined as in formula (II) in claim 1.

12. The method according to any one of claims 10 and 1 1, wherein the molar ratio of

Compound (III) or the compound (II) to the molar fraction of the groups Q is <1 to 1, and preferably at most 0.95.

13. The method according to any one of claims 10 to 12, wherein in the for the third reaction

used compound of the formula (III) or (II) Q has the meaning R ¹ , comprising a fourth reaction with a compound of the formula (III)

XW- (Q) _b (III)

14. The method according to any one of claims 10 to 12, wherein in the for the third reaction

used compound of the formula (III) or (II) Q is selected from OH, the

Carboxylic acid residue -COOH and a salt or ester thereof, comprising a fourth reaction with a compound (II)

Y- (W) _k - (Q) _b (II)

wherein Y, W, Q, k and b are defined as in formula (II) in claim 1.

15. The method according to any one of the preceding claims, further comprising

(a) reacting the respective process product with a di-, tri-, tetra- or

polyfunctional thiol or

(B) reacting the respective process product with a di-, tri-, tetra- or

polyfunctional amine or

(C) the polymerization of the respective process product in a polyreaction, in which a part or all of the reactive double bonds present under the influence of heat, light, ionizing radiation or redoxinduziert in a propagating

Carbon chain can be installed. A process according to any one of claims 1 to 14, wherein Q is selected from OH, the carboxylic acid residue -COOH and a salt or ester thereof, further comprising

(a) the crosslinking of at least a portion of the hydroxy present or

Carboxylic acid groups with a di-, tri-, tetra- or polyfunctional isocyanate or

(b) if Q is -OH, crosslinking of existing hydroxy groups with a di-, tri-, tetra- or polyfunctional, optionally activated carboxylic acid or anhydride,

(c) when Q = COOH, crosslinking of existing carboxyl groups with a di, tri, tetra or polyfunctional alcohol.

Compound or silicic acid (hetero) polycondensate of the formula (3),

wherein

the three unspecified bonds of the Si atom for further, am

Silicon atom-bonded radicals, selected from radicals which can be hydrolyzed off from silicon, hydroxyl groups, radicals bonded via a carbon atom on the silicon and oxygen bridges to further silicon atoms or other metal atoms,

the zigzag line represents the backbone of a hydrocarbon radical bonded to the silicon via a carbon atom, which backbone may optionally be branched and optionally substituted by heteroatoms or coupling groups or other

Heteroatom-containing groups may be interrupted, wherein the

Hydrocarbon radical except for the grouping AW (B (W) _k (Q)) _{a is} free of functional

Groups,

A represents a coupling group selected from -S-, -NH- and NHR ³ ,

B represents a coupling group selected from ester, ether, acid amide and urethane groups,

-C (S) NH-, -NHC (S) -, -NHC (S) O-, wherein R ^{3 represents} an unsubstituted or substituted hydrocarbon radical or a (meth) acrylic group,

Q is either R ¹ or OH, NR ⁷ ₂ , NRV, CO ₂ H, SO ₃ H, PO (OH) ₂ , PO (OR ⁴ ) ₂ , (0) PO (OH) ₂ , (0) PO (OR ⁴ ) ₂ or a salt of the aforementioned acids, wherein R ^{1 is} an unsaturated, organically polymerizable group and R ^{4 is} an unsubstituted or substituted hydrocarbon radical, R ^{7 has} either the same meaning as R ⁴ or two radicals R ⁷ together may denote an optionally substituted, optionally unsaturated alkylene group, the index k is 0 or 1,

the index m is 1, 2 or an integer greater than 2,

a = 2, 3, 4, 5 or a larger integer,

b is 1, 2, 3, 4 or a larger integer.

18. Compound or silicic acid (hetero) polycondensate of the formula (A)

where D is selected from A'W (Q) _b , B (W) _k (Q) _b , A'W (AW (Q) _b ) _b , A'W (B (W) _k (Q) _b ) _bl B (W) _k (AW (Q) _b ) _b and B (W) _k B (W) _k (Q) _b ) _b where

Q, A, B, W, k, m, a and b have the meaning given in claim 17 and A 'is a coupling group formed by the attack of the group X of a compound XW (Q) _b , wherein X is selected from SH , NH ₂ and NHR ³ with R ³ = unsubstituted or substituted hydrocarbon radical, at the C = C double bond of an unsaturated, organically polymerizable group R ¹ .

19. Organic polymer obtained from a compound or a

Silica (hetero) polycondensate according to any one of claims 17 and 18, wherein at least part of the radicals Q is an unsaturated, organically polymerisable group

(A) reacting the compound or the silicic acid (hetero) polycondensate with a di- or polyfunctional thiol or amine or

(B) polymerizing the compound or the silicic acid (hetero) polycondensate in a polyreaction in which a part or all of the existing reactive

Double bonds under the influence of heat, light, ionizing radiation or redoxinduced be incorporated into a propagating carbon chain.

20. Organic polymer obtained from a compound or a

Silica (hetero) polycondensate according to either of Claims 17 and 18, in which at least part of the radicals Q is OH or COOH

(a) crosslinking of existing hydroxy or carboxylic acid groups with a di- or

polyfunctional isocyanate or the crosslinking of existing hydroxy groups with a di- or polyfunctional, optionally activated carboxylic acid, or the crosslinking of existing carboxylic acid groups with a di- or polyfunctional alcohol.