EP3841153A1

EP3841153A1 - Composition precursor, composition, method for producing a composition precursor, method for producing a composition, use of a composition, and component

Info

Publication number: EP3841153A1
Application number: EP19753402.7A
Authority: EP
Inventors: Guido KICKELBICK; Nils Steinbrück; Svenja Pohl
Original assignee: Universitaet des Saarlandes
Current assignee: Universitaet des Saarlandes
Priority date: 2018-08-23
Filing date: 2019-08-20
Publication date: 2021-06-30
Also published as: WO2020038935A1; EP3613793A1; US20210317271A1

Abstract

The invention relates to a composition precursor comprising a three-dimensional network consisting of partially cross-linked monomer units and an alkoxy-terminated oligo- or polysiloxane, wherein the monomer units comprise at least one trialkoxysilane and at least one dialkoxysilane. The invention further relates to a composition, to a method for producing a composition precursor and to a composition, to a use of a composition and to a component.

Description

description

Composition precursor, composition, method for producing a composition precursor, method for producing a composition, use of a

Composition and component

The application relates to a composition precursor, a composition, a method for producing a

Composition precursors, a method for producing a composition, a use of the composition and a component.

Polysiloxanes are used in many areas. There are increasing demands on these materials, so that commercially available systems have to be improved.

A possible application of polysiloxanes is, for example, the encapsulation of optoelectronic components. The working conditions of light emitting diodes (LEDs) require, for example, high photophysical and thermal stability, high transparency, a high refractive index and good processability

hardened and non-hardened encapsulation materials to ensure high efficiency and long life of the

To ensure component.

For example, based on polysiloxane

Encapsulation materials are used, which are based on two-component elastomer systems and are thermally curable using a platinum catalyst. For ecological and economic reasons, however, the use of non-recyclable precious metals such as platinum should be avoided. Previously known epoxy-based polysiloxanes, which without Platinum can be hardened, but are sensitive to heat or light, so that, for example, discoloration occurs due to the presence of the epoxy groups. A high degree of flexibility of the materials is often required, which has not been possible so far.

The object of at least one embodiment of the invention is to provide a composition precursor which has improved properties. Another object of the invention is to provide a composition which has improved properties. Other tasks are to provide a method of making a composition precursor with improved ones

Properties and a method for producing a composition with improved properties. Another object of the invention is to use the

Composition with improved properties

provide. Finally, it is a further object of the invention to provide a component which

Contains composition and has improved properties.

These tasks are solved by the subject matter of the independent claims. Advantageous configurations and

Further developments of the invention are the subject of dependent claims and the description.

A composition precursor is specified, which is a three-dimensional network partially with each other

crosslinked monomer units and an alkoxy-terminated oligo- or polysiloxane. Under a composition precursor is here and in

The following is a material to understand, which means

Influence of external influences on a composition

is convertible. The external influences initiate chemical reactions in the composition precursor which change the chemical structure of the composition precursor in such a way that it is converted to the composition. Properties caused by the material of the composition can be adjusted by adjusting the properties of the

Composition precursors can be achieved.

The composition precursor can be a polymeric material that has the three-dimensional network. It should be noted that not all components of the

Composition precursors must be networked, but can also be available individually. Thus, the

Composition precursor monomer units,

alkoxy-terminated oligo- or polysiloxane as well as monomer units connected by chemical bonds as well as monomer units and alkoxy-terminated oligo- or polysiloxane which are linked by chemical bonds.

“Monomer units” are therefore to be understood here and in the following as well as both unreacted monomers and

Units of a polymer chain that are due to these monomers.

According to one embodiment, the monomer units comprise at least one trialkoxysilane and at least one dialkoxysilane.

That the monomer units have at least one trialkoxysilane (hereinafter also referred to as TAS) and at least one In this context, dialkoxysilane (hereinafter also referred to as DAS) means that at least two different trialkoxysilanes or at least two different dialkoxysilanes as monomer units in the

Composition precursors can be present.

Partly that of at least one TAS, at least one DAS and an alkoxy-terminated oligo- or polysiloxane

crosslinked composition precursors can be gel-like

Have consistency and therefore at room temperature

for example in liquid or viscous form.

The viscosity and refractive index of the

Composition precursors can be selected by selecting the

Starting materials, i.e. the monomer units and the alkoxy-terminated oligo- or polysiloxane, and the

Ratio of the proportions of the respective starting materials can be set. For example, these properties are directly related to the ratio of TAS to DAS used and the proportion of certain groups,

especially bulky groups such as aryl groups, the

Monomer units. Furthermore, the alkoxy terminated

Oligo- or polysiloxane to an expanded

three-dimensional network of the partially cross-linked monomer units, which in turn has an influence on the viscosity.

By adjusting the viscosity and the refractive index of the composition precursor, the hardness and the refractive index of a composition produced from the composition precursor can also be influenced and thus adjusted depending on the desired application. According to one embodiment, a

Composition precursor specified, the one

three-dimensional network of partially with each other

has crosslinked monomer units and an alkoxy-terminated oligosiloxane or polysiloxane, the monomer units having at least one trialkoxysilane and at least one dialkoxysilane.

According to a further embodiment, the

Composition precursor the general structural formula

on. R ¹ , R ² , R ³ and R ⁴ can be selected independently of one another from aryl, alkyl, alkenyl, allyl,

substituted aryl, substituted alkenyl, substituted alkyl and vinyl, preferably from phenyl and methyl, where u + v + w is the number of Si atoms used and u, v and w are independently selected from the range 1 to 20,000.

In this structural formula it should be noted that the groups indexed with u, v and w are statistically distributed in the at least partially networked network. So it can other orders of groups also occur in the network.

For example, phenyltrimethoxysilane PhSi (OMe) ₃ and methyltrimethoxysilane MeSi (OMe) ₃ which are partially crosslinked or not crosslinked as trialkoxysilanes, dimethyldimethoxysilane can thus be used in the composition precursor

Me ₂ Si (OMe) ₂ as dialkoxysilane and methoxy-terminated polydimethylsiloxane, PDMSin (OMe) ₂ as alkoxy-terminated oligosiloxane or polysiloxane. Their general structures are shown below:

PhSl (O e) 3 MeSi (OMe) 3 Me ₂ si {O e) 2 PDMSiiiOMe) 2

According to this example, the general structural formula of such a network can look like this:

The higher the proportion of DAS in relation to TAS and

alkyl-terminated oligo- or polysiloxane, the more

The structure of the composition precursor and thus also that of it is expanded and less cross-linked resulting composition what the viscosity of the

Composition precursors or the hardness of the composition significantly reduced. At the same time, the refractive index can increase due to the larger ratio of, for example, phenyl to methyl groups.

According to a further embodiment, the proportion of alkoxy-terminated oligo- or polysiloxane is in the

Composition precursor from a range of> 0% to 10% of the sum of the amounts of trialkoxysilane and

Dialkoxysilane selected. Such a proportion is sufficient to expand the three-dimensional network and thus to lower the viscosity of the composition precursors.

According to a further embodiment, the

Composition precursor has a viscosity at 23 ° C, which is in a range from 1000000 mPas to 100 mPas,

and / or a viscosity at 110 ° C, which is in a range from 10000 mPas to 50 mPas. These viscosities enable the composition precursor to be easily processed. In addition, they require a hardness from the

Composition precursor manufactured composition that has a desired flexibility and elasticity

Composition realized.

According to a further embodiment, the

Composition precursor thermally or photochemically curable. This means that the composition precursor can harden completely by thermal or photochemical effects, so that all or at least largely all

Monomer units and alkoxy-terminated oligo- or

Polysiloxanes together to form a three-dimensional network are networked. This hardening process can be done here and in

Also referred to below as consolidation.

A composition is also specified which is thermally or photochemically cured

Composition precursor according to one of the above-mentioned embodiments. All features that in

Context with the composition precursor are thus also valid for the composition and

vice versa .

Because the composition has a thermally or photochemically hardened composition precursor

contains, it is not gel-like like that

Composition precursor, but fixed. Due to the

The properties of the composition precursor show the

However, the composition has a sufficiently high elasticity so that it can be used well in many applications, for example as an encapsulation in optoelectronic components.

According to a further embodiment, the

Composition has a Shore A hardness of 40 to <99.

Depending on the property of the composition precursor, the composition can continue to have a high refractive index

exhibit. This can be greater than or equal to the refractive index of the composition precursor.

According to a further embodiment, the composition is free of a noble metal catalyst. In particular, the composition is free of a platinum catalyst. The composition can thus be produced in a cost and process-optimized manner. Based on a composition

Composition precursor, the phenyltrimethoxysilane

PhSi (OMe) ₃ and methyltrimethoxysilane MeSi (OMe) ₃ as

Trialkoxysilanes, dimethyldimethoxysilane Me ₂ Si (OMe) ₂ als

Dialkoxysilane and methoxy-terminated polydimethylsiloxane, PDMSin (OMe) ₂ as alkoxy-terminated oligo- or polysiloxane, the cured or consolidated structure can have the following schematic formula in an exemplary section:

This formula shows the TAS and DAS groups as well as the PDMS groups that expand the network.

There continues to be a method of making a

Composition precursors specified. The procedure has the steps

A) condensation of at least one trialkoxysilane and at least one dialkoxysilane,

B) condensation of the at least one trialkoxysilane and the at least one dialkoxysilane with an alkoxy-terminated oligo- or polysiloxane,

C) purification of the condensed trialkoxysilane,

Dialkoxysilans and alkoxy-terminated oligo- or

Polysiloxane. According to one embodiment, process step B) can be carried out after process step A) or simultaneously with the

Process step A) are carried out.

Condensation here and below means a reaction of the monomer units with one another or with the alkoxy-terminated oligo- or polysiloxane, in which the monomer units and the alkoxy-terminated

Combine oligo- or polysiloxane chemically. This creates a three-dimensional network. It should be noted, however, that not all in this procedure

Monomer units or not each

alkoxy-terminated oligo- or polysiloxane with each other

react so that only partial networking occurs.

At least two different trialkoxysilanes and / or at least two different ones can also be used in the process

Condense dialkoxysilanes.

Regardless of whether process steps A) and B) are carried out simultaneously or in succession, a statistical distribution of the

used components can be obtained in the composition precursor. Furthermore, the alkoxy-terminated oligo- or polysiloxane ensures that an expanded network of mutually condensed monomer units is formed.

With this method, a composition precursor can be produced in accordance with the above-mentioned embodiments. All of the features disclosed in connection with the composition precursor therefore also apply to the method and vice versa. According to one embodiment, process steps A) and B) are carried out at a temperature selected from the range from 20 ° C. to 60 ° C., and / or process step C) is carried out at a temperature consisting of the

Range 70 ° C to 150 ° C is selected. With these

Temperatures is the formation of a three-dimensional

Network of at least partially crosslinked trialkoxysilanes, dialkoxysilanes and alkoxy-terminated oligosiloxane or polysiloxane.

According to a further embodiment, the

Process step A) carried out with the addition of an acid or a base. For example, HCl, H ₂ SO ₄ ,

Vinegar or formic acid can be used. Exemplary bases are NaOH, KOH, NH ₄ OH or NH ₃ . In general, the acids or bases used are water-soluble. If an acid is added, protonation of the alkoxy groups and thus an increase in electrophilicity at the silicon atom can be produced. This allows water, alkoxysilane and

Attack silanol groups and substitute methanol as a leaving group. Bases can be directly attached to the nucleophile

Attack the silicon atom and form a charged transition state. The alkoxysilane group can thus be substituted in an SN2-like reaction. Will in

Process step A) an acid is added, the probability of forming chain-like structures can increase, if a base is added, the

Probably to form branched structures

increase .

According to a further embodiment, before

Process step C) the condensed trialkoxysilane,

Dialkoxysilane and alkoxy-terminated oligo- or polysiloxane stirred at room temperature. That means that before

Cleaning step C) a gelation is carried out, whereby the viscosity of the material increases.

In the cleaning step C), water formed during the gelation, as well as HCl and methanol formed by the condensation can be removed.

There continues to be a method of making a

Composition specified, in which a according to the above

Designs of manufactured composition precursors

is cured thermally or photochemically. Due to the action of heat or light, the gel-like composition precursor can become a solid composition

getting produced. All related to the

Methods for producing a composition precursor thus also apply to the method for producing the composition and vice versa.

According to a further embodiment, the thermal curing is carried out at a temperature in the range from 150 ° C. to 250 ° C. and / or for a period in the range from 8 h to 72 h.

Photochemical curing can be carried out in the presence of a photochemically activatable group in a monomer,

for example, a propyl methacrylate group. After adding a photoinitiator, these can

Groups react with each other. Furthermore can also

Photoacids that release protons on exposure can be used to activate curing. According to a further embodiment, a base or acid can be added as a catalyst to the composition precursor. If, for example, a base is added, the curing time and curing temperature can be considerably reduced. As a base, for example, KOH or DABCO

(Triethylenediamine) can be used. The proportion of base can be, for example, <10 mmol / g.

The composition obtained by the process is free from cracks, depending on the composition precursor used

flexible and elastic and has a high refractive index.

The use of a composition according to the above embodiments is also specified. Use of the composition includes use as

Encapsulation material of optoelectronic components, as matrix material of conversion layers, as

Lens material, as corrosion protection material, as a component in composite materials, in lithography processes and in printing technology.

For example, the composition can be used as a positive in an embossing lithography process in which a stamp is placed. Furthermore, the composition

for example, photolithographic processes, in particular in a photolithographic 3D printing. Furthermore, the composition can serve as a matrix for dyes, for example in solar cells or luminescence solar concentrators, with the materials being deposited in thin films using an inkjet process. Because of the possibility in the composition of the

Refractive index as well as the elasticity and flexibility

adjust, the composition can be used advantageously in many areas.

It will continue to have at least one component

Component specified that contains a composition according to the above statements. The component can according to one

Embodiment be an optoelectronic component and contain an encapsulation comprising the composition and / or a conversion layer having the composition.

The optoelectronic component can

act, for example, a light emitting diode (LED) and this can have a semiconductor layer sequence which is suitable for the emission of primary radiation. An LED can have a conversion layer that is in the beam path of the

Primary radiation is arranged and for converting the

Primary radiation is set up in secondary radiation. The encapsulation can be arranged in the component such that it surrounds the semiconductor layer sequence.

The composition is well suited as an encapsulation material for LEDs due to its high refractive index, its high transparency and its stability to radiation and heat.

According to a further embodiment, the composition in the conversion layer can be a matrix material for a dye which converts the primary radiation into secondary radiation. Here, the composition can be used advantageously, since it is light and heat stable and thus a long one Lifetime and reliability of the component can contribute.

Furthermore, the conversion layer can be formed as a plate or as a potting. In the case of encapsulation, the conversion layer can completely surround the semiconductor layer sequence.

If the composition is to be used in a component, the composition precursor, in which further substances such as, for example, are added, is first used

Dyes are stored in the desired location

applied. This is particularly feasible due to the low viscosity of the composition precursor and thus its good processability. As soon as it is applied, hardening or consolidation can be carried out, which makes the hard but still elastic

Forms composition, wherein the hardness of the composition can be adjusted by suitable adjustment of the composition precursor.

Further advantages, advantageous embodiments and

Further training results from the following in

Connection described with the figures

Embodiments.

FIG. 1 shows a schematic view of the methods for producing a composition precursor and one

Composition.

FIG. 2 shows a graphical representation of the proportions of starting materials used to produce the Composition precursors according to various

Embodiments.

Figure 3 shows the absolute viscosity of

Embodiments of the composition precursor using a block diagram.

FIG. 4 shows a representation of the refractive indices and the content of phenyl groups of exemplary embodiments of the composition precursor.

FIG. 5 shows a representation of the Shore A hardness of

Embodiments of the composition based on a block diagram.

Figure 6 shows images of platelets according to

Embodiments of the composition.

Figures 7a to 7f show lead frames with and without

Composition precursors and compositions according to exemplary embodiments.

FIG. 8 shows the thermogravimetric mass loss (a) and T95 values (b) of exemplary embodiments of the composition.

FIG. 9 shows the absolute viscosity as a function of time from exemplary embodiments of the

Composition precursors.

FIG. 10 shows FTIR spectra of exemplary embodiments of the composition precursor. FIGS. 11 to 14 show ² H and ²⁹ Si NMR spectra of

Starting materials for the production of a

Composition precursors.

Figures 15 to 20, 25 and 26 show ^! H-NMR spectra and ²⁹ Si- ¹ H HMBC 2D NMR spectra of exemplary embodiments of the composition precursor during and after it

Manufacturing.

Figures 21 to 24 show ² H-NMR spectra of

Embodiments of composition precursors.

Figure 27 shows the schematic side view of a

Component.

In the exemplary embodiments and figures, identical, similar or identically acting elements can each be provided with the same reference symbols. The elements shown and their proportions are not to scale. Rather, individual elements such as layers, components, components and areas can be shown in an exaggerated manner for better representation and / or for better understanding.

For the production of embodiments of

Composition precursors and compositions can be used, for example, the following starting materials and auxiliaries: dimethyldimethoxysilane (97%, ABCR GmbH), methyltrimethoxysilane (97%, ABCR GmbH),

Phenyltrimethoxysilane (97%, ABCR GmbH), methoxy-terminated polydimethylsiloxane (5 to 12 cst., ABCR GmbH), 1,4-diazabicyclo [2.2.2] octane (98% Alpha Aesar, Germany), hydrochloric acid (Bernd Kraft GmbH) and potassium hydroxide (85%, Grüssing GmbH Analytica). The hydrochloric acid is in

demineralized water dissolved (pH = 2.3). Potassium hydroxide is dissolved in methanol (0.11 mol / 1).

The purity of the starting materials and the average chain length of the methoxy-terminated polydimethylsiloxane are determined by means of ² H and ²⁹ Si NMR spectroscopy (see FIGS. 11 to 14: FIG. 11 shows the spectra of

Phenyltrimethoxysilane, Figure 12 shows the spectra of

Methyltrimethoxysilan, Figure 13 shows the spectra of

Dimethyldimethoxysilane and Figure 14 shows the spectra of methoxy-terminated polydimethylsiloxane). The NMR spectra were recorded with an Avance III 300 MHz spectrometer and an Avance III HD 400 MHz spectrometer (Bruker Corp., USA) at 300.13 / 400.13 MHz for ¹ H-NMR spectra and 59.63 / 79 , 49 MHz for ²⁹ Si NMR spectra. The ones to be measured

Samples were dissolved in methanol-d4 or chloroform-d.

Composition based on an embodiment. First, hydrochloric acid with a pH of 2.5 is added to PhSi (OMe) 3 as TAS, MeSi (OMe) 3 as TAS and Me2Si (OMe) 2 as DAS. The

Hydrochloric acid is added in a proportion of 1.5 times the amount of alkoxysilanes. This mixture is stirred in a closed vessel at 45 ° C. for 3 hours and at 320 rpm. This is identified in FIG. 1 as method step A). In process step B)

methoxy-terminated polydimethylsiloxane PDMSin (MeO) 2 was added in a proportion of 0.7% of the amount of the alkoxysilanes and further stirred at 45 ° C. for 18 hours at 320 rpm. The PDMSin (MeO) 2 can also be added simultaneously with process step A) (not shown here). The mixture is transferred to a beaker and stirred at 25 ° C for 0.5 to 1 hour at 150 rpm. This gelation step is optional and therefore marked with dashed lines. The gelation can be recognized by the fact that homogeneously distributed gas bubbles form in the material and the viscosity increases significantly.

In process step C), the cleaning step, the beaker is transferred to a drying cabinet and water, hydrochloric acid and methanol are removed there at 110 ° C. for one hour. Finally, the transparent, gel-like

Composition precursor G isolated and cooled to room temperature.

A composition precursor obtained as described above can be consolidated or hardened by transferring it into a mold or cavity and hardening it there at 150 to 200 ° C. for 8 to 72 hours. The curing time is related to the proportions of the respective starting materials of the composition precursor and the thickness of the sample to be cured. Optionally, a small proportion of base or acid (only base shown here) can be added to the composition precursor before the start of hardening in order to achieve the

Reduce curing time and temperature. This optional step is indicated by the dashed line. The hardened composition CM is free of cracks and, depending on the selected viscosity of the composition precursor, is flexible and elastic.

In process steps A) and B), as described in relation to FIG. 1, the trialkoxysilanes and dialkoxysilanes are hydrolyzed and form an oligomer and polymer chains and, in some cases, crosslinked structures. A step by step Substitution of MeSi (OMe) 3 by Me2Si (OMe) 2 leads to a more chain-like and less cross-linked structure.

This also increases the viscosity of the formed

Composition precursors. The polydimethylsiloxane added in process step B) leads to an additional expansion of the network. If the temperature is increased during these steps, the viscosity increases at the same time, which simplifies the manufacturing process. By a

Heat treatment of the composition precursors

Temperatures of over 150 ° C will be another

network building process started. The gel-like

Composition precursors now form a solid but elastic polymer, the composition CM. With this

Hardening process will not be catalysts or others

Components needed to harden the composition precursor. However, it is possible to add small amounts of base or acid to the process

To catalyze composition precursors. The

Consolidation time or hardening time and the temperature can be determined by the pH dependence of the

Condensation reaction can be reduced.

For example, the composition precursors G for hardness tests can be placed in PTFE molds of size 30x10x1 mm and films of size 13x0.12 mm can be produced on glass plates for transmission measurements. Examples 1 and 2, which are specified in more detail below, were heated to 110 ° C. for better handling. The Quadrupel Film Applicator Model-360 (Erichsen GmbH & Co. KG) can be used for film production. The thickness of the films can be measured with an FMD12TB precision dial gauge (Käfer Messuhrenfabrik GmbH & Co. KG) with an accuracy of 1 ym. The samples prepared in this way can, for example, at 200 ° C. be cured in a drying cabinet for 72 hours. The transparent compositions CM are then on

Cooled and insulated at room temperature.

Table 1 shows the exact proportions of the starting materials of the composition precursors according to Examples 1 to 8:

Table 1

Eight composition precursors (designated Sample 1 to 8 in Table 1) were prepared. Table 1 shows the substance quantities n of the respective starting materials

specified, as well as the proportions of the summed trialkoxysilanes TAS, the dialkoxysilanes DAS and the polydimethylsiloxane PDMS in mol%. Furthermore, the proportion of phenyl groups Ph

[calc.] / Ph t ¹ ]! NMR] indicated in relation to the

Total number of alkyl and aryl groups can be seen. The calculated proportion of the weighed quantities is divided by the calculated proportion from the integration of the NMR spectra.

While the proportion of PhSi (OMe) 3 and PDMSin (MeO) 2 was kept constant, in Examples 1 to 8 the proportion of MeSi (OMe) 3 is gradually replaced by Me2Si (OMe) 2. This Substitution of a methyltrialkoxysilane by a dimethylalkoxysilane leads to an expanded and less cross-linked structure of the resulting

Composition precursors and thus also the hardened composition (CM). This results in a significantly reduced viscosity of the composition precursors or hardness of the compositions. At the same time, the refractive index increases due to the larger ratio of phenyl to methyl groups.

In the following, reference is further made to Examples 1 to 8. When referring to the compositions made from the respective composition precursors, the numbering 1 to 8 is retained and the addition CM is added.

Figure 2 shows the substance amounts n in mmol of the starting materials used in Examples 1 to 8 (x-axis). Here you can clearly see that the share of

PhSi (OMe) 3 and PDMSin (MeO) 2 were kept constant in all examples (square and downward triangle), while the proportions of MeSi (OMe) 3 (circle) and Me2Si (OMe) 2 (upward-looking triangle) have been changed. In particular, the substitution of MeSi (OMe) 3 by Me2Si (OMe) 2 can be seen.

The absolute values of the viscosities were oscillated using a MCR-301 rheometer with a CTD-450 convection heating system (Anton Paar GmbH, Austria) with a plate-plate geometry (25 mm PP25 measuring plate), an amplitude of 5%, a frequency of 1 Hz and a normal force of 0 was measured. FIG. 3 shows the averaged absolute values of the viscosity of samples 1 to 8, which were measured isothermally at 23 ° C. and at 110 ° C. for 10 minutes each. The absolute values of viscosity at room temperature (| r | * | @ 23 ° C in mPas) and at 110 ° C (| r | * | @ 110 ° C in mPas) can be determined directly after the synthesis of the composition precursors. It decreases from Examples 1 to 8, that is to say with an increase in the substituted content of MeSi (OMe) 3 by Me2Si (OMe) 2, as shown in FIG. 3. The viscosity of Examples 1 and 2 is too high to be measured at room temperature. When the samples are heated to 110 ° C, the absolute value of the viscosity decreases significantly. All examples can easily be processed at 110 ° C. Due to their viscosity, samples 3 to 8 can also be processed at room temperature, which makes the materials suitable, for example, as curable encapsulation material for optoelectronic components.

If the composition precursors are stored and thus subjected to an aging process, their viscosity can increase with the storage time at room temperature. Become

for example samples of Example 4 after 60 days of

Storage examined, it can be shown that the viscosity increases from 50 Pas to 420 Pas. This aging is generated by the still flexible network of the composition precursor, which further the Si-OMe and Si-OH groups

Condensation reactions enabled. The aging can

avoided or at least reduced if the samples are stored at a lower temperature. However, the aged composition precursors can still

can be processed because they soften at temperatures above 23 ° C. If the composition precursors are used to be used in encapsulations of optoelectronic components, it is important that they have a defined and preferably high refractive index. Height

Refractive indices in composition precursors (and thus also in the compositions hardened from them) can be favored by the presence of mono- or polycyclic aromatic side groups. In samples 3 to 8, the proportion of phenyl groups changes from 37% to 32%, as shown in FIG. 4 (left y-axis). At the same time, the refractive index n _D ^{20 changes} from 1.505 to 1.494 (right y-axis). The refractive index can be measured, for example, with an AR4 Abbe refractometer with a PT31 Peltier thermostat (A. Krüss Optronic GmbH) at 20 ° C and 590 nm LED radiation. The gradual substitution of MeSi (OMe) 3 by Me2Si (OMe) 2 reduces the proportion of phenyl groups in the samples, which also lowers the refractive index. This shows that the drop in the refractive index correlates directly with the proportion of phenyl groups in the samples. The refractive index of samples 1 and 2 could be due to their very high

Viscosity cannot be determined at 20 ° C.

The values for the refractive indices between 1.505 and 1.494 of the composition precursors are high enough for that

Application in optoelectronic components.

By substituting MeSi (OMe) 3 with Me2Si (OMe) 2, i.e. the proportion of phenyl groups in the

Composition precursors, the hardness of the associated compositions can be adjusted, which may have different requirements depending on the application. The hardness of the consolidated compositions can be measured at room temperature using a Shore A durometer become. You can do this with individual sample plates

be placed on top of one another in order to achieve the minimum required thickness. FIG. 5 shows the hardness H in Shore-A for Examples 1 CM to 6 CM, which decreases with increasing proportion of Me2Si (OMe) 2 and with increasing temperature. The

Samples 7 CM and 8 CM were too soft to determine hardness. A higher proportion of Me2Si (OMe) 2 leads to longer and less cross-linked polymer chains. This expansion of a previously close-knit structure leads to a decrease in the hardness of the compositions.

The decreasing hardness among samples 3, 5 and 7 is also shown in FIG. 6, in which images can be seen, in each of which a magnet weighing 1.9 g is placed on one

Sample plate was placed. In the case of the plate made from a composition according to Example 3 CM, this does not lead to any

Bending, according to Example 7 CM to a strong bend.

For the applications in optoelectronic components, the encapsulation material is highly transparent

required. For example, the entire visible spectrum of light is emitted in white LEDs. For one

Comparable transmission measurement, all samples of the composition precursors are processed into a polymer film, which is applied to glass plates using a film applicator (13 x 0.12 mm). This makes all the samples

uniform, without inclusions or bubbles and have a uniform thickness. These samples are in one

Drying cabinet hardened at 200 ° C for 72 hours. The samples shrink due to the consolidation process. The

actual film thickness was determined at three different locations for each sample before the sample was UV / VIS

(Lambda 750 from Perkin Elmer Inc., USA, with a 100 mm Integration range from 700 to 350 nm with a 2 nm

Increment and 0.2 s integration time) was measured. The film thickness for the 1 CM sample is 81 ± 1 μm, for the sample

2 CM 61 ± 2 ym, for the sample 3 CM 51 ± 5 ym, for the sample 4

CM 95 ± 8 ym, for the sample 5 CM 63 ± 2 ym, for the sample 6

CM 48 ± 2 ym, for the sample 7 CM 42 ± 2 ym, and for the sample

8 CM 35 ± 5 ym. All samples show transmission values of over 0.99 between 350 and 730 nm immediately after

Curing process. The shrinkage of the samples does not appear to be systematic. The high transparency is ideal for use in all kinds of optical applications, especially in optoelectronic components.

Encapsulation materials for optoelectronic components must be pourable, hardenable and leakproof. Becomes a

Composition precursor arranged as encapsulation material in a component and then to one

Hardened composition, it must be free of cracks and bubbles and have a certain elasticity. To determine the applicability of the composition precusors in

To demonstrate optoelectronic components, samples 4 and 6 were cast on a polyphtalamide LED lead frame (1.4 x 0.7 x 0.4 mm) and the lead frame for curing the composition precursors at 160 ° C for 20 hours

heat treated.

Figures 7a to f show images of the empty lead frame (Figures 7a and b), the lead frame with a

Composition precursor of Example 4 and one

Composition 4 CM (Figures 7c and d) and one

Lead frame with a composition precursor of

Example 6 and a composition 6 CM (Figures 7e and f). The picture in Figure 7a is on the metallic background focused, in Figure 7b on the upper edge of the

Lead frame. In Figure 7c the colored impression is generated by the metallic base plate, the same applies to Figure 7d. The bubbles visible in FIG. 7e, which were generated by the application of the composition precursor, disappear after the hardening process, as can be seen in FIG. 7f. Both cast composition precursors 4 and 6 show very good processability. After curing, there can be no bubbles or cracks within the

Compositions 4 CM and 6 CM are measured. Using the side edges of the lead frames as a reference before and after curing, a shrinkage of the materials can be recognized. Overall, the composition precursors and thus the compositions are well suited for

Encapsulation material for LED applications.

Another important property in different

Applications of composition precursors and

Compositions, among others in LED applications, is a high temperature stability of the material. Under

Working conditions in an LED can raise the local temperature to over 150 ° C. Therefore, the hardened ones

Compositions heated to 800 ° C with a heating rate of 10 K / min and under N2 / O2 with a gas flow of 20 ml / min (with a TG209 Fl Libra thermo-microbalance from Netzsch-Gerätebau GmbH) to measure their decomposition behavior, what can be seen in Figure 8. The temperature at which 95% of the mass of the sample remains after decomposition is defined as the T95 value. The higher the T95 value, the more heat-stable the composition. In Figure 8a

Thermographimetric mass loss of Examples 1 CM to 8 CM shown. The mass M is plotted in% against the

Temperature T in ° C. All samples show high thermal stability up to 400 ° C. Figure 8b shows for the Compositions 1 CM to 8 CM obtained T95 values. This is above 360 ° C for all samples, which makes them suitable for applications with high working temperatures. No decomposition of the samples is measured at temperatures below 200 ° C. This also shows a very high thermal stability of the

Samples.

As already mentioned above, the hardening process can

Preparation of the composition can be catalyzed by the addition of small amounts of a base or acid to the composition precursor. The base can, for example, be added directly before the heat treatment of the composition precursors. For example, KOH and DABCO can be used as bases

be used. In order to show the change in viscosity, in a composition precursor of Example 4 which had aged for 60 days, the viscosity was measured isothermally at 110 ° C. after the addition of different amounts of KOH. No KOH was added in sample 4-MO, 5.5 mmolg ^-1 in sample 4-M1 and 13.9 mmolg ^{-1 in} sample 4-M2. For this, potassium hydroxide (0.093 g, 1.65 mmol) was dissolved in methanol (14.949 ml, 0.369 mol, 0.11 mol / 1). From this solution, the amounts of 0.0, 1.0 and 2.5 mΐ to the samples of

Example 4 (0.2 g) and mixed.

All three examples show a drop in viscosity | h * | with an initial increase in temperature T. Samples 4-MI and 4-M2 show a significant increase in viscosity at 110 ° C while the viscosity of 4-MO remains almost constant. So the increase in viscosity is direct

correlates with the amount of KOH added to the samples. These relationships are shown in FIG. 9, in which the time t in minutes on the X axis and the viscosity | h * | on the left Y axis in mPas and on the right Y axis Temperature T in ° C are specified. The viscosity was measured with an oscillation rheometer at 5 K / min and an amplitude of 5% at a frequency of 1 Hz and a normal force of 0 N starting at 110 ° C. It can thus be shown that the curing time and temperature can be adapted to every need by appropriately selecting the amount of base added. The curing temperature must be optimized for each composition in order to avoid the formation of bubbles, for example due to the formation of methanol. If the composition hardens too quickly, bubbles will remain in it. Pretreatment under reduced pressure before pouring the

Composition precursors can remove solvent residues. If a weaker base is used without a solvent, for example DABCO (pK _b = 5.2), the formation of bubbles can also be avoided or reduced.

All samples show the expected vibrational bands when measured by FTIR spectroscopy (measured in

Total reflection mode with a Vertex 70 spectrometer from Bruker Corp., USA from 4500 to 400 cm ^-1 with a 4 nm

Increment and 10 averaged scans). The FTIR spectra of Examples 1 to 8 are shown in Figure 10a, where the relative absorption A _rei as a function of the energy E in cm ^-1

is specified. The gradual substitution of the methyltrimethoxisilanes by dimethyldimethoxisilanes can thus be shown. As a result of the substitution, the intensity of the band at 1269 cm ^-1 decreases, while the intensity at the band at 1259 cm ^-1 increases. FIG. 10b shows an enlarged section of the FTIR spectrum of Examples 1 to 8, which shows the decrease in the vibration band at 1269 cm ^-1 , which is caused by the decreasing proportion of MeSi (OMe) 3 in the examples. Furthermore, the increase in Vibration band shown at 1259 cm ^-1 , which is caused by an increasing content of Me2Si (OMe) 2.

The condensation behavior of various monomer units used in the synthesis of the composition precursor can be determined using two-dimensional ²⁹ Si- ¹ H

Nuclear magnetic resonance spectroscopy (2D-NMR) can be followed. The results of a heteronuclear

Multiple Binding Correlation Experiment (HMBC)

Composition precursors 1, 2, 3 and 8 are shown in Table 2 below. To carry out the experiment, small amounts of the samples of the respective reaction mixture were obtained after 3 hours of hydrolysis (before the addition of the

PdMSin (MeO) 2) and after the synthesis of the

taken from the respective composition precursors. Ranges of the peaks are given in each case, since a high

Concentration of different types of molecules

(hydrolyzed and non-hydrolyzed molecules, monomers, oligomers, polymers, rings etc.) is present, which the ²⁹ Si chemical shifts very broad and therefore the resolution

make difficult.

-1S ...- 22 0.36 ...- 0.26 D ² + + + +

-15 ...- 18 0.36 ...- 0.26 D ² + # * *

Table 2

The associated spectra together with the ^! H-NMR spectra of the other examples of the composition precursors are shown in FIGS. 15 to 26.

Show:

Figure 15: Sample 1 after 3h, Figure 16: Sample 1 after the

Synthesis, Figure 17: Sample 2 after 3h, Figure 18: Sample 2 after synthesis, Figure 19: Sample 3 after 3h, Figure 20: Sample 3 after synthesis, Figure 21 ^:! H-NMR spectrum of sample 4, Figure 22 ^:! H-NMR spectrum of sample 5, Figure 23 ^:! H-NMR spectrum of sample 6, Figure 24 ^:! H-NMR spectrum of sample 7, Figure 25: Sample 8 after 3h, Figure 26: Sample 8 after

Synthesis.

The spectra of samples 1, 2, 3 and 8 show the possible chemical shifts of the trifunctional T unit apart from T ° (see also Table 2, in which the functional groups F are given). This shows that the phenyltrimethoxysilane monomers and methyltrimethoxysilane monomers have reacted at least once with a second molecule or part of a linear or cross-linked structure. In addition, it appears that every T signal except T ³ matches the chemical

Shift of the methoxy groups is coupled. It can be concluded that significantly less trifunctional

Molecules were hydrolyzed before reacting with other molecules.

The chemical shifts caused by difunctional D units of Me2Si (OMe) 2 groups show different behavior. No unreacted D ° signals can be detected in samples 1 and 2. All

Monomers reacted with a second at least once

Molecule or part of a linear or cross-linked structure, as can be observed by the observed D ¹ and D ² signals. The D ^! Signals can be divided into D ³ o and D ² i signals. The indexed numbers indicate the proportion of hydroxyl groups attached to a molecule. A D ³ o signal is generated by a monomer with none

Hydroxyl group generated, a D ^ signal is generated by a monomer with a hydroxyl group. The additional D ^ signal can be separated by the chemical shift and is measurable since there is no coupling with the methoxy groups

consists. In the spectra of samples 3 and 8, D ¹ signals of the end groups and D ² signals of linear or cross-linked units are observed. D ° signals can be measured on unreacted monomers. The reaction does not appear to have ended after stirring for three hours. TAS monomers thus react with one another and with DAS monomers, forming straight and cross-linked structures. As the DAS concentration increases, the number of unreacted DAS monomers increases, while the number of unreacted TAS monomers is 0 in each sample. It can be concluded from this that the condensation reaction between TAS and DAS monomers is preferred compared to a reaction between two DAS molecules. After further synthesis steps, D ° signals can no longer be measured. The monomers have reacted with the structures previously formed.

Figure 27 shows the schematic side view of a

optoelectronic component according to one

Embodiment. The component, for example an LED, comprises a substrate 10 on which one

Semiconductor layer sequence 20 is arranged. The

Semiconductor layer sequence 20 is for the emission of

Primary radiation, for example short-wave light with a wavelength maximum of about 450 nm, set up.

There is one in the beam path of the primary radiation

Conversion layer 30 arranged. This envelops the

Semiconductor layer sequence 20 completely, that is to say materially and positively, and is thus introduced as a potting in a recess in the housing 40. So that serves

Conversion layer 20 on the one hand as an encapsulation of the

Semiconductor layer sequence 20, on the other hand for converting the primary radiation into a secondary radiation. The

Conversion layer contains a dye that is in a Matrix, which is formed from a composition, is embedded.

Alternatively, the conversion layer 30 can be arranged at a distance from the semiconductor layer sequence 20 (not shown here). In this case, you can choose between the

Semiconductor layer sequence 20 and the conversion layer 30 an encapsulation, which is formed from the composition, may be arranged.

The invention is not restricted to the exemplary embodiments by the description based on these. Rather, the invention encompasses every new feature and every combination of features, which in particular includes every combination of features in the patent claims, even if this feature or the combination itself is not explicitly described in the

Claims or exemplary embodiments is specified.

LIST OF REFERENCE NUMBERS

10 substrate

20 semiconductor layer sequence 30 conversion layer

40 housing

A Process step A

B method step B

C Process step C n amount of substance

| H * | absolute viscosity riD ²⁰ refractive index

H hardness

M mass

T temperature

T95 Tgs value

t time

A _rei relative absorption

E energy

G composition precursor CM composition

Claims

claims

1. Composition precursor comprising a three-dimensional network of partially networked with one another

Monomer units and an alkoxy-terminated oligo- or polysiloxane, the monomer units being at least one

Trialkoxysilane and at least one dialkoxysilane include.

2. Composition precursor according to claim 1, having the general structural formula

wherein R ¹ , R ² , R ³ and R ^{4 are} independently selected from aryl, alkyl, alkenyl, allyl, substituted aryl, substituted alkenyl, substituted alkyl and vinyl, preferably from phenyl and methyl, where u + v + w is the number of the Si atoms used and u, v and w are independently selected from the range 1 to 20,000.

3. Composition precursor according to one of the preceding claims, wherein the proportion of alkoxy-terminated oligosiloxane or polysiloxane is selected from a range from> 0% to 10% of the sum of the amounts of trialkoxysilane and dialkoxysilane.

4. Composition precursor according to one of the preceding claims, which has a viscosity at 23 ° C, which is in a range from 1000000 mPas to 100 mPas and / or has a viscosity at 110 ° C, which in a range from 10000 mPas to 50 mPaS lies.

5. Composition precursor according to one of the preceding claims, which is thermally or photochemically curable.

6. A composition comprising a thermally or photochemically cured composition precursor according to any one of the preceding claims.

7. The composition according to the preceding claim, which has a Shore A hardness of 40 to <99.

8. The composition according to any one of claims 6 to 7, which is free of a noble metal catalyst.

9. A method of making a composition precursor with the steps

B) condensation of the trialkoxysilane and the dialkoxysilane with an alkoxy-terminated oligosiloxane or polysiloxane,

C) purification of the condensed trialkoxysilane,

Dialkoxysilans and alkoxy-terminated oligo- or

Polysiloxane, wherein process step B) after the

Process step A) or simultaneously with the

Process step A) is carried out.

10. The method according to claim 9, wherein the method steps

A) and B) are carried out at a temperature consisting of the range 20 ° C to 60 ° C is selected, and / or

Process step C) is carried out at a temperature which is selected from the range from 70 ° C. to 150 ° C.

11. The method according to any one of claims 9 to 10, wherein process step A) is carried out with the addition of an acid or a base.

12. The method according to any one of claims 9 to 11, wherein prior to process step C) the condensed trialkoxysilane, dialkoxysilane and alkoxy-terminated oligo- or polysiloxane is stirred at room temperature.

13. A method for producing a composition in which a manufactured according to one of claims 9 to 12

Composition precursor is cured thermally or photochemically.

14. The method according to the preceding claim, wherein the thermal curing is carried out at a temperature in the range from 150 ° C to 250 ° C and / or for a duration in the range from 8h to 72h.

15. The method according to any one of claims 13 or 14, wherein a base or acid as a catalyst to the

Composition precursor is added.

16. Use of a composition according to claims 6 to 8 as encapsulation material of optoelectronic

Components, as matrix material of conversion layers, as lens material, as corrosion protection material, as

Component in composite materials, in lithography processes in printing technology.

17. Component comprising at least one component that contains a composition according to one of claims 6 to 8.

18. The component according to the preceding claim, which is an optoelectronic component and an encapsulation comprising the composition and / or

Conversion layer (20) comprising the composition.

19. The component according to the preceding claim, wherein the

Composition in the conversion layer (20)

Matrix material for a wavelength converting dye is.