WO2019149356A1

WO2019149356A1 - Adducts of hydrogen peroxide comprising urea-functional siloxanes

Info

Publication number: WO2019149356A1
Application number: PCT/EP2018/052442
Authority: WO
Inventors: Michael Stepp
Original assignee: Wacker Chemie Ag
Priority date: 2018-01-31
Filing date: 2018-01-31
Publication date: 2019-08-08

Abstract

The invention relates to novel hydrogen peroxide silicone adducts containing: (A) urea-functional organopolysiloxanes consisting of units of formula (I) R_nSiO_(4-n ₎ _/2, where R is a group R¹ or a group -OR² or a group Q, where R is a monovalent, optionally halogenised C₁-C₁₈-hydrocarbon group, R² is a hydrogen atom or a monovalent C₁-C₆-hydrocarbon group, and Q is a urea-functional group of formula (II) -R⁵-[NR⁴-R^6-]_xNR⁴R³ (II), where R³ is a hydrogen atom or a monovalent C₁-C₆-hydrocarbon group, R⁴ is the same or different and is a group R⁴' or a group R^u, where R⁴' is a hydrogen atom or a monovalent C₁-C₆-hydrocarbon group, R^u is a group of formula (III) -C(=O)-NH₂ (III), R⁵ is a divalent C₁-C₁₈-hydrocarbon group, R⁶ is a divalent C₁-C₁₈-hydrocarbon group, x is 0, 1 or 2 and n is 0, 1, 2 or 3 and preferably is on average between 2.00 and 2.66, with the proviso that the organopolysiloxanes consisting of units of formula (I) contain per molecule at least one urea-functional group Q which has a group R^u; and (B) hydrogen peroxide.

Description

Adducts of hydrogen peroxide with urea-functional

siloxanes

The invention relates to adducts of urea-functional siloxanes with hydrogen peroxide, their preparation and their use.

Hydrogen peroxide is in demand as a disinfectant because, in contrast to many other antimicrobial substances such as e.g. Silver nanoparticle has no environmentally relevant disadvantages. It disintegrates - relatively slowly without catalysis - into the harmless substances oxygen and water and is therefore, especially in physiological environment, a preferred agent not only for disinfection purposes but also in cosmetic applications e.g. as a bleaching agent for bleaching hair, for bleaching teeth or for fixing perms or as

Deodorant. In most cases, aqueous preparations are used ver. This is useful in rinses (e.g., mouthwashes, ear drops), but may become more desirable upon prolonged contact with human or animal tissue, e.g. for wound disinfection or treatment or in technical applications e.g. Peroxide reactions (polymerizations, crosslinks) be a disadvantage.

It is known that hydrogen peroxide with urea functions forms adducts. The known body "carbamide peroxide" (H ₂ NC (= 0) -NH ₂ * H ₂ 0 ₂ ) contains about 35 wt .-% H ₂ 0 ₂ and offers as solid and anhydrous hydrogen peroxide with higher

Stability and better controllability Advantages over liquid hydrogen peroxide as oxidizing agent e.g. in chemical reactions. But even this product can only be used neat in solid form or as an aqueous preparation. In addition, urea is used in its applications

released, the physiologically largely harmless is, but keratolytic acts, which is undesirable especially for prolonged contact with the skin, hair and mucous membranes.

With a liquid, pasty or gelatinous, possibly, plastically deformable solid form of hydrogen peroxide formulation, these disadvantages could be avoided, provided that the carrier material physiologically has less influence than urea. One way to bind hydrogen peroxide is by adduct formation with suitable polymers, e.g. Polyvinylpyrrolidone or polyvinylcaprolactam, as in

US 5,945,032 A described. However, the products are usually solid and can only be converted into liquid, pasty or gel-like formulations with other components and correspondingly high expenditure.

It was therefore the task of physiologically inert

To provide hydrogen peroxide adducts whose

Hydrogen peroxide content and its homogeneous appearance, such as liquid, solid, gel or pasty, can be varied within wide limits, which can be easily prepared, in which phase separation of a hydrogen peroxide-rich (aqueous) phase, for. is avoided during storage and with which a controllable effect can be achieved.

The invention relates to hydrogen peroxide-containing silicone adducts

(A) urea-functional organopolysiloxanes of units of the formula (I)

RnSi-0 (4-n) / 2 (I)

in which

R is a radical R ¹ or a radical -OR ² or a radical Q, where R ^{1 is} a monovalent optionally halogenated

Hydrocarbon radical having 1 to 18 carbon atoms,

R ² denotes a hydrogen atom or a monovalent C 1 -C ₆ -hydrocarbon radical,

Q is a urea-functional radical of the formula (II)

R ⁵ - [NR ⁴ -R ⁶ -] _X NR ⁴ R ³ (II),

in which

R ³ denotes a hydrogen atom or a monovalent C 1 -C ₆ -hydrocarbon radical, preferably a hydrogen atom,

R ^{4 is the} same or different and a radical R ⁴ 'or

a radical R ^u means where

R ⁴ 'denotes a hydrogen atom or a monovalent C 1 -C ₆ -hydrocarbon radical,

R ^{u is} a radical of formula (III)

-C (= O) -NH ₂ (III)

R ^{5 is} a divalent C 1 -C 6 -hydrocarbon radical,

preferably a divalent C 2 -C 4 -hydrocarbon radical,

R ^{6 is} a divalent C ¹ -C ⁶ -hydrocarbon radical,

preferably a divalent C 2 -C 4 -hydrocarbon radical,

x is 0, 1 or 2 and

n is 0, 1, 2 or 3, and preferably is 2.00 to 2.66 on average,

with the proviso that in the organopolysiloxanes

Units of the formula (I) at least one urea

functional radical Q, which has a radical R ^u , per

Molecule is included

and

(B) hydrogen peroxide. Preferably, it is hydrogen peroxide silicone adduct consisting of

(A) urea-functional organopolysiloxanes from units of the formula (I) and

(B) hydrogen peroxide.

In the organopolysiloxanes of units of the formula (I) according to the invention preferably mean

at least 50% of all radicals R is a C ¹ -C ₆ -alkyl radical R ¹ ,

at least 0.1% of all radicals R is a radical Q of the formula (II), where in at least one radical Q at least one radical R ^{4 has} the meaning of R ^u and

at most 3% of all radicals R is a radical -OR ² ,

wherein Q, R, R ¹ , R ² , R ⁴ and R ^{u are} those given above

Have meaning.

The organopolysiloxanes of units of formula (I) may be linear, cyclic or branched and may be oligomeric or polymeric. Preferably, they contain at least 3 Si atoms and at most 2000 Si atoms, preferably at most 600 Si atoms.

Organopolysiloxanes are as constituents of creams,

Hair rinses and also in external medical applications have long been established and can be found in a variety of

Manifest forms of appearance such as liquid, pasty or gel-like. They behave physiologically inert, theirs

However, polarity is so low that they are immiscible with highly polar constituents such as water, but can only be emulsified. It was therefore surprising and unpredictable that urea-functional organopolysiloxanes, in spite of the low polarity of the methylsiloxy group, form homogeneous, clear hydrogen peroxide adducts which open the way to a multiplicity of applications. Compared with the previously known solid hydrogen peroxide polymer adducts adducts of the invention have the

Advantage that you can be in liquid form.

The urea-functional organopolysiloxanes of units of the formula (I) are preferably organopolysiloxanes of the formula (IV)

Q _k R * _3-k SiO (R ¹ ₂ SiO) _{m (Q} R * SiO) _p SiR * _3-kQk (IV) where

R * is a radical R ¹ or a radical -OR ² ,

R ¹ and R ² are as defined above,

Q is a urea-functional radical of the formula (II)

R ⁵ - [NR ⁴ -R ⁶ -] _X NR ⁴ R ³ (II),

in which

R ^{3 is} a hydrogen atom or a monovalent C 1 -C ₆ -hydrocarbon radical, preferably a hydrogen atom,

means

R ^{4 is the} same or different and is a radical R ⁴ 'or a radical R ^u , where

R ⁴ 'denotes a hydrogen atom or a monovalent C 1 -C ₆ -hydrocarbon radical and

R ^{u is} a radical of formula (III)

-C (= O) -NH ₂ (III),

R ^{5 is} a divalent C 1 -C 6 -hydrocarbon radical,

preferably a divalent C 2 -C 4 -hydrocarbon radical,

R ^{6 is} a divalent C ¹ -C ⁶ -hydrocarbon radical,

preferably a divalent C 2 -C 4 -hydrocarbon radical,

k is 0 or 1,

m is 0 or an integer from 1 to 1000, p is 0 or an integer from 1 to 50 and

x is 0, 1 or 2,

with the proviso that in the organopolysiloxanes of the formula (IV) at least one urea-functional radical Q having a radical R ^u is contained per molecule.

Examples of hydrocarbon radicals R ¹ are alkyl radicals such as the methyl, ethyl, n-propyl, iso-propyl, n-butyl, 2-butyl, iso-butyl, tert. Butyl, n-pentyl, iso-pentyl, neo-pentyl, tert. -Pentyl radical, hexyl radicals such as the n-hexyl radical, heptyl radicals such as the n-heptyl radical, octyl radicals such as the n-octyl radical and iso-octyl radicals such as the 2, 2, 4-trimethylpentyl radical, nonyl radicals such as the n-nonyl radical, and Decyl radicals, such as the n-decyl radical;

Cycloalkyl radicals, such as cyclopentyl, cyclohexyl,

4-ethylcyclohexyl and cycloheptyl radicals, norbornyl radicals and methylcyclohexyl radicals; Alkenyl radicals, such as the vinyl,

2-propen-2-yl, allyl, 3-buten-1-yl, 5-hexen-1-yl and

10-undecene-1-yl-rest; Cycloalkenylreste, like the

2-cyclohexenyl, 3-cyclohexenyl, cyclopentadienyl, and

2- (cyclohex-3-en-1-yl) ethyl radical aryl radicals, such as the phenyl, biphenylyl, naphthyl radical; Alkaryl radicals, such as o-, m-, p-tolyl radicals and phenylethyl radicals, such as the 2-phenylethyl and 1-phenylethyl radical and aralkyl radicals, such as the benzyl radical.

When R ^{1 is} a halogenated hydrocarbon radical, the halo radicals on R ^{1 are} preferably fluoro radicals.

Examples of halogenated hydrocarbon radicals R ¹ are the 3, 3, 3-trifluoropropyl and 5, 5, 5, 4, 4, 3, 3-heptafluoropentyl.

The radicals R ¹ preferably have 1 to 6 C atoms, preferably 1 to 4 C atoms. R ¹ is particularly preferably a methyl radical. If R ^{1 is} an unsaturated radical, the vinyl radical is

prefers . Examples of the hydrocarbon radicals R ² , R ³ or R ⁴ 'having 1 to 6 C atoms are listed in the examples of R ¹ .

Preferred hydrocarbon radicals are each ethyl and

Methyl radicals.

Preferably, R ^{3 is} a hydrogen atom.

Examples of radicals R ⁵ are radicals of the formula

-CH ₂ -, -CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -CH ₂ - and -CH ₂ -CH (CH ₃ ) -CH ₂ -.

Examples of radicals R ⁶ are radicals of the formula

-CH ₂ -CH ₂ - and -CH ₂ -CH ₂ -CH ₂ -.

Preferred urea-functional radicals Q of the formula (II) are radicals of the formula

-CH ₂ -CH ₂ -CH ₂ -NH-C (= O) -NH ₂ ,

-CH ₂ -CH ₂ -CH ₂ -NH ₂ -CH ₂ -CH ₂ -NH-C (= O) -NH ₂ ,

-CH ₂ -CH ₂ -CH ₂ -NH [-C (= O) -NH ₂ ] -CH ₂ -CH ₂ -NH-C (= O) -NH ₂ and

-CH ₂ -CH ₂ -CH ₂ -NH [-C (= O) -NH ₂ ] -CH ₂ -CH ₂ -NH ₂ .

Process for the preparation of the urea-functional

Organopolysiloxanes are known and z. For example, in US 3,772,351 A and US 4,046,794 A described.

The urea-functional organopolysiloxanes of units of the formula (I) according to the invention are preferably prepared by reacting amino-functional organopolysiloxanes of units of the formula (V)

R ' _{n is} SiO ₍₄ -n _{) / 2} (V),

in which

R 'is a radical R ¹ or a radical -OR ² or a radical A

means, where

R ¹ , R ² and n have the meaning given above and A is an amino-functional radical of the formula (VI)

R ⁵ - [NR ⁴ '- R ⁶ -] _X NR ⁴ ' R ³ (VI),

in which

R ³ , R ⁴ ', R ⁵ , R ⁶ and x have the meaning given above, with the proviso that in the organopolysiloxanes from units of the formula (V) at least one amino-functional radical A is contained per molecule,

with carbamic acid aryl esters of the formula (VII)

R ⁷ -Ar-0-C (= O) -NH ₂ (VII),

in which

Ar is an optionally substituted aryl radical, preferably a phenyl radical or a substituted phenyl radical, and

R ^{7 is} a hydrogen atom or a substituent bonded to Ar, wherein R ^{7 is} a Ci_C ₆ alkyl radical, a Ci-C _{6 ~}

Carboxalkylrest, a Ci_C ₆ alkoxy or a

Halogen radical means

be implemented.

When Ar contains a substituent R ⁷ , Ar may be next to

Substituent R ⁷ contain further substituents in ortho ', meta or para position.

In the preparation of R ⁷ -Ar-OH is cleaved, wherein Ar and R ^{7 have} the meaning given above, preferably when using an ortho-substituted carbamic phenyl ester, an ortho-substituted phenol cleaved.

Examples of radicals R ⁷ are the methyl, ethyl, propyl,

Isopropyl, methoxy, ethoxy, carboxyethyl, carboxymethyl, fluoro, chloro and bromo. The reaction of the carbamic acid aryl esters with the amino functions in the organopolysiloxanes from units of the formula (V) preferably does not significantly alter the siloxane skeleton.

In the organopolysiloxanes used from units of the formula (V) are preferably

at least 50% of all radicals R is a C ¹ -C ₆ ^-alkyl radical R ¹ ,

at least 0.1% of all radicals R is a radical A of the formula (VI) and at most 3% of all radicals R is a radical -OR ² ,

where A, R, R ¹ and R ^{2 have} the meaning given above.

The organopolysiloxanes of units of formula (V) may be linear, cyclic or branched and may be oligomeric or polymeric. Preferably, they contain at least 3 Si atoms and at most 2000 Si atoms, preferably at most 600 Si atoms.

Preferred amino-functional radicals A of the formula (VI) are radicals of the formula

-CH 2 -CH 2 -CH 2 -NH 2 and

CH2-CH2-CH2-NH2-CH2-CH2-NH2.

In the preparation of the urea invention

functional organopolysiloxanes are preferred as amino-functional organopolysiloxanes of units of the formula (V)

Organopolysiloxanes of the formula (VIII)

A ^ s-iSiO (R ¹ ₂ SiO) ₀ (AR * SiO) _q SiR * ₃ -iAi (VIII) used where

R * and R ¹ are as defined above,

A is an amino-functional radical of the formula (VI) R ⁵ - [NR ⁴ '- R ⁶ -] _X NR ⁴ ' R ³ (VI),

in which

R ³ , R ⁴ ', R ⁵ , R ⁶ and x are as defined above, 1 is 0 or 1,

o is 0 or an integer from 1 to 1000,

q is 0 or an integer from 1 to 50

with the proviso that in the organopolysiloxanes of the formula (VIII) at least one amino-functional radical A per molecule is contained.

The ortho-substituted Carbaminsäurearylester of formula (VII) used in the process according to the invention can be prepared by literature methods.

Preferably, their preparation is carried out by reacting the respective ortho-substituted phenol with chlorosulfonyl isocyanate and subsequent hydrolysis according to Singh, R. et al. , ACS Catalysis 6 (10), 6520-6524 (2016). The recovered from the inventive method according to the ortho-substituted phenols can thus be converted back into this process in the corresponding carbamate and recycled, which is a

represents another advantage of the method according to the invention.

As preferred, because commercially available, ortho-substituted phenols come in the inventive

Process as raw materials (and at the same time fission products) the following in question:

2-methylphenol (= o-cresol),

2- (1-methylethyl) -5-methylphenol (= thymol),

2-methyl-5- (1-methylethyl) phenol (= carvacrol)

2-ethylphenol,

2-methoxyphenol (= guaiacol),

2-chlorophenol 2-hydroxybenzoic acid methyl ester (= methyl salicylate) and

2-hydroxybenzoic acid ethyl ester (= ethyl salicylate).

Particularly preferred are 2-methoxyphenol (= guaiacol) and 2-methyl-5- (1-methylethyl) phenol (= carvacrol).

The adducts according to the invention have the advantage that they can be in liquid form. You have one

Viscosity of preferably 10 to 1,000,000 mPa.s at 25 ° C, preferably measured according to DIN 53019 Parts 1, 2 and 3 on a Physica MCR301 Rheometer Fa. Anton Paar.

The invention further relates to a method for

Preparation of the hydrogen peroxide-silicone adducts according to the invention by reaction of

(A) urea-functional organopolysiloxanes from units of the formula (I) or the formula (IV)

(B) hydrogen peroxide.

The hydrogen peroxide can be in pure form or dissolved in water or dissolved in an organic solvent

be used.

In the method according to the invention, the two

Components urea-functional organopolysiloxane (A) and hydrogen peroxide (B) e.g. mixed in a stirred tank, a kneader or a tubular reactor and optionally separated water and / or solvent preferably separated by distillation.

This can be done by simple batch distillation optionally via a distillation column from the mixing unit or

downstream using standard distillation

carried out devices such as falling film evaporator, thin film evaporator, flash evaporator or short path distillation. Mixing and distillation can also be done in a single aggregate

be carried out for example in a thin-film evaporator. Good mixing is advantageous for adduct formation because the two pure components are generally immiscible or poorly miscible with one another. Preference is therefore given to using hydrogen peroxide inert solvents in which at least one component is soluble, preferably organic solvents are used in which both components are at least partially soluble. Especially

Preference is given to using organic solvents which form an azeotropic mixture with water, as described in EP 0 098 427 A1, which facilitates the distillative separation of the water and promotes the formation of the adduct according to the invention. The reaction can be accelerated if the solvent is already removed during the mixing process. This is particularly preferably done by reducing the pressure.

The reaction temperature is just chosen so high that the desired adduct formation proceeds as quickly as possible,

However, undesirable side reactions (such as oxidations) are largely avoided and the hydrogen peroxide remains in the mixture.

The inventive method is preferably carried out at a temperature of at most 100 ° C, preferably at most 80 ° C, in particular at most 70 ° C, and at a temperature of preferably at least 20 ° C, preferably at least 50 ° C.

To achieve a high space-time yield with low reaction

To achieve temperature is preferably as possible

implemented low pressure, preferably less than or equal

900 hPa, particularly preferably less than or equal to 500 hPa, in particular less than or equal to 300 hPa. The chosen conditions depend on the particular solvent and can be easily determined by taking into account the known substance data or by preliminary experiments. When using aqueous hydrogen peroxide solutions are preferably those solvents are used which have a miscibility gap with water, so that they can be easily separated from the water phase and recycled.

Residual proportions of water and / or hydrogen peroxide thus do not interfere. They do not have to be removed when the solvent is reused, which in turn has a positive effect on the economic efficiency of the process. Contains the water phase of the distillate certain

Proportions of hydrogen peroxide, so they can before a

Derivation to a treatment plant with the usual, preferably heterogeneous catalytic methods are decomposed into oxygen and water. When using aqueous hydrogen peroxide solutions and azeotropic tractor with miscibility gap, the solvent is preferably in the distillation after

Condensation separated in a water and returned to the mixing unit. This is the most preferred procedure.

The solvents used are preferably linear, branched or cyclic alkanes or alkylaromatics and linear or branched alkyl, cycloalkyl or aryl esters of saturated carboxylic acids which have a total of not more than 10 carbon atoms and form an azeotrope with water. They are usually commercially available at low cost. It can too

Mixtures of different solvents can be used.

Examples of usable solvents are: cyclohexane, methylcyclohexane, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, n-hexane, n-heptane, i-octane, Isopar® C (Exxon Mobil), Methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, t-butyl acetate, i-butyl acetate, phenyl acetate, methyl propionate, ethyl propionate, methyl butyrate and ethyl butyrate.

For each urea function, a hydrogen peroxide molecule can be bound. Accordingly, the maximum possible loading of hydrogen peroxide with knowledge of the urea group density in the organopolysiloxane can be easily determined.

The adducts according to the invention have a content of hydrogen peroxide preferably in the range of 0.2 to 20 wt .-% H2O2, preferably the hydrogen peroxide content is less than 10 wt .-%, in particular less than 5 wt .-%, each based on the

Total weight of the adducts according to the invention. Compared with the equimolar ratio of urea: hydrogen peroxide, larger or smaller ratios can also be set, homogeneous mixtures only starting at stoichiometric

equal molar ratio or lower amounts of hydrogen peroxide based on the polymer-bound urea functions can be realized. Also in the adduct of urea-functional organopolysiloxane and hydrogen peroxide according to the invention, residual water can lead to inhomogeneities. These can preferably be removed by subsequent heating, preferably at reduced pressure.

The degree of conversion or loading, d. H. the

Hydrogen peroxide concentration, in the adduct according to the invention can be easily determined by determining the peroxide content

for example by titration, e.g. on an aqueous

Extract, or by spectroscopic methods, eg IR or ¹ H NMR spectroscopy, determine. Another possibility is to compare the amount of hydrogen peroxide weighed in Solution with the amount of distillate. However, since even small proportions of hydrogen peroxide pass into the distillate, the proportion removed from the mixture would therefore also have to be determined for the most exact possible content determination.

Depending on the urea-functional organopolysiloxane used and the choice of the mixing ratio, the hydrogen peroxide-silicone adducts according to the invention can be prepared in a wide variety of variants. By this unlimited variety of possible combinations (polymer molecular weight, polymer structure, urea functionality, hydrogen peroxide loading) very different systems are available, e.g. differ in polarity or viscosity and which can each be optimized for the desired application. For example, blends with gelling agents, such as silicic acids or other solids or liquids, can also be prepared. By the simultaneous presence of crosslinkable, such as unsaturated, aliphatic radicals, e.g. Vinyl, 5-hexenyl, cyclohexenyl, acrylic or

Methacryl radicals, or alkoxy or aryloxy radicals in the urea-functional organopolysiloxanes used as a component for the adducts according to the invention can also

thermally crosslinked by irradiation or condensation

Follow-on products, such as elastic or gel-like vulcanizates are produced. These can come with solutions from

Hydrogen peroxide in solvents such as volatile alkyl esters of alkanecarboxylic acids by swelling and evaporation of the

Solvent be reloaded again. Also blends with other polymers containing crosslinkable groups or

Monomers can form crosslinked shaped bodies with the adducts according to the invention. Examples of these are moisture- or addition-crosslinkable polysiloxane mixtures, monomeric acrylates or methacrylates, epoxies, polyamides, polyurethanes and

Polyimides.

It is also possible to add to the adducts or their mixtures according to the invention peroxide stabilizers, such as phosphoric acid or phosphoric acid (partial) ester which is more preferably miscible with the organopolysiloxane.

Among the multitude of possible applications, especially those which are in direct contact with the skin and the mucous membranes are to be emphasized, since as residue after the decomposition of the hydrogen peroxide only the physiologically acceptable urea-functional organopolysiloxane remains. Examples include: wound disinfection or bleaching of skin, hair and teeth, in particular by application of the adducts according to the invention as gels or high-viscosity pastes, the antimicrobial finish of

Paper towels and textiles, the antimicrobial coating of surfaces or the preservation of emulsions, e.g. in cosmetics. Also for technical applications, in particular those in which non-aqueous peroxides are advantageous, e.g. in the peroxide crosslinking of silicone rubber or other peroxidically crosslinkable polymers, the use of the adducts according to the invention offers new possibilities.

Examples for the preparation of the adducts according to the invention:

Example 1 :

In a 250ml 4-necked flask with magnetically coupled stirrer, thermocouple and 20 cm packed column (glass rings) and

Condensation attachment with water separator (filled with

n-propyl acetate) were 50 g (= 0.014 moles of urea) of an organopolysiloxane of the middle formula ViSiMe ₂ 0i _{/ 2} : Me ₂ Si0 _2/2 : MeSi [(CH ₂ ) ₃ -NH-C (= O) -NH ₂ )] 0 _2/2 = 2: 46.8: 1.1 (Vi = Vinyl, Me = methyl)

initially charged and 1.6 g (= 0.016 mol) of hydrogen peroxide solution (35% in water, Fa.) added. After addition of 51.6 g of n-propyl acetate, the pressure in the apparatus was reduced to 250 hPa and heated. At a bottom temperature of 65 ° C and a head temperature of 45 ° C, water was removed from the system. As soon as no more water separated in the water, the sump was on a rotary evaporator at 60 ° C / 1 hPa

baked. 47.3 g of a colorless clear oil were obtained.

By means of ¹ H-NMR spectroscopy, the content of hydrogen peroxide could be determined by the integral ratio of the signals at 0.5 ppm (CH ₂ -Si group) and 8.4 ppm (H ₂ O ₂ ) of 1: 0.35. It was 0.1 mmol H ₂ 0 ₂ / g. Accordingly, 35% of the amount of H ₂ 0 _{2 was used} as urea adduct. After one week of storage at room temperature about 25 ° C were still 34.8%, after four weeks 31.5% as an adduct.

Example 2:

Condensation attachment with water separator (filled with

n-propyl acetate) were 50 g (= 0.06 moles of urea) of a

Organopolysiloxane of the middle formula

MeOSiMe ₂ Oi _{/ 2} : Me3SiOi _{/ 2} : Me ₂ Si0 _2/2 : MeSi [(CH ₂ ) ₃ -N (-C (= O) -NH ₂ ) -CH ₂ CH ₂ -NH-C (= 0) -NH ₂ ] 0 _2/2 = 1.5: 0.5: 28.2: 1.6

submitted and 8.8 g (= 0.09 mol) of hydrogen peroxide solution

(35% in water, Kraft) added. After addition of 53 g of n-propyl acetate, the pressure in the apparatus was reduced to 250 hPa and heated. At a bottom temperature of 65 ° C and a head temperature of 45 ° C, water was removed from the system. As soon as no more water separated in the water, the sump was on a rotary evaporator at 60 ° C / 1 hPa baked. This gave 51.4 g of a colorless clear oil.

By means of ¹ H-NMR spectroscopy, the content of hydrogen peroxide could be determined by the integral ratio of the signals at 0.5 ppm (CH ₂ -Si group) and 8, 4-8, 6 ppm (H2O ₂ ) of 1: 1.8 , It was 1 mmol H 2 O 2 / g.

Example 3:

In a 250ml 4-necked flask with magnetically coupled stirrer,

Thermocouple and 20cm packed column (glass rings) and

Condensation attachment with water separator (filled with

n-Propylacetat) were 45 g (= 0.012 mol of urea) of a

Organopolysiloxane of the middle formula

ViSiMe 0i _{_2/2:} Me ₂ Si0 _2/2: MeSi [(CH _{2) 3} -NH-C (= 0) -NH _2] 0 _{_2/2} = 2: 49 3: 1.1 (0.27 mmol urea / g)

initially charged and added 3, 6 g (= 0.037 mol) of hydrogen peroxide solution (35% in water, Fa. Kraft). After addition of 48.6 g of n-propyl acetate, the pressure in the apparatus was reduced to 250 hPa and heated. At a bottom temperature of 65 ° C and a head temperature of 45 ° C, water was removed from the system.

As soon as no more water separated in the water, the sump was on a rotary evaporator at 60 ° C / 1 hPa

baked. This gave 44 g of a colorless clear oil.

By means of ¹ H NMR spectroscopy (CDCI3) could be on the

Integral ratio of the signals at 0.5 ppm (CH2-Si group) and 8.4 ppm (H2O2) of 2: 0.98 the content of hydrogen peroxide can be determined. It was 0.139 mmol H 2 O 2 / g. Accordingly, 51% of the urea functions were present as H202 adduct. The viscosity was 681 mPa.s at 25 ° C (measured according to DIN 53019 Parts 1, 2 and 3 on a Physica MCR301 Rheometer) Example 4:

Test for antibacterial effectiveness:

Additivation of WACKER Elastosil® M4514

(condensation-curing 2-component silicone rubber)

Three vulcanizate sheets were produced:

4a) without additive (= reference)

4b) with the urea-functional organopolysiloxane used in Example 3

4c) with the BHCc adduct of urea-functional

Organopolysiloxane prepared according to Example 2

4a) 114 g of WACKER Elastosil® M4514 base material were homogenized with 6 g of WACKER® Hardener T37 with the Speedmixer for 2 minutes at 2500 rpm. The mass was poured into a mold and allowed to become an elastic at room temperature overnight

Harden Vulkanisatplatte with 2 mm thickness (= reference plate).

4b) 21.5 g of urea-functional organopolysiloxane

Example 3 was mixed with the spatula in 95 g of WACKER Elastosil® M4514 base material. The mixture was then homogenized with the speed mixer for 1 minute at 2500 rpm. Thereafter, 5 g WACKER® Hardener T37 were mixed in with the spatula and it was again homogenized with the Speedmixer for 1 minute at 2500 rpm. The mass was poured into a mold and allowed to become an elastic at room temperature overnight

Harden vulcanizate plate with 2 mm thickness. The plate theoretically had a urea concentration of 0.048 mmol

Urea functions / g. Twenty-five 5mm * 5mm * 2mm small platelets were excised and an Adherence Proliferation Test to Old with Staphylococcus aureus

subjected (test description see below). The results are summarized in the table. The vulcanizate had none significant antibacterial activity, as shown in the table.

4c) The procedure described in 4b) was repeated with 19.44 g of the bhiCg adduct of the urea-functional organopolysiloxane prepared according to Example 2, 86 g of WACKER Elastosil® M4514 base material and 4.5 g of hardener T37, so that pure

arithmetically, the plate has a urea concentration of

0.048 mmol urea functions / g and 0.024 mmol ^ Cg / g. The results of the antibacterial efficacy test are summarized in the table. In contrast to 4a) and 4b), the vulcanizate showed a significant antibacterial activity, as can be seen from the table. Table:

The proliferation test was carried out with the three Vulkanisatplatten analogous to the provisions of T. Bechert, P.

Steinbruecke, J-P Guggenbichler: A new method for screening anti-infective biomaterials, Nature Medicine, 2000, 6: 1053-

1056 and V. Alt, P. Steinbruecke, M. Wagener, P. Seidel, E.

Wesenidein, E.Domann, R. Schettler: In Vitro Testing of Antimicrobial Activity of Bone Cement, in: Antimicrobial Agents and Chemotherapy, 2004, 48: 4084-4088.

Microplate proliferation test method according to

Guggenbichler and Alt:

The microtiter plate proliferation assays used in the present assays for silicone rubber samples were based on one for antimicrobial screening

Biomaterials introduced test procedures (1 and 2).

For the test, 25 pieces (5 mm long,

5 mm wide, 2 to 3 mm high) of the sample and the same amount of control pieces each with 5 × 10 ⁶ bacterial CFU (strain DSM 799 from Staphylococcus aureus, freshly prepared seed culture broth) in 200 PBS (Phosphate-Buffered Saline, pH 7 , 4) supplemented with 10% TSB (Tryptic Soy Broth), incubated per well (well) of a 96-well microtiter plate at 37 ° C for 1 h to adhere the bacteria to the silicone rubber surface.

After incubation, loosely adherent cells were removed from the silicone surfaces in two steps, in which the rubber samples were rinsed with 300 mM PBS. In the first rinsing step, the pieces to be tested were transferred to a new microtiter plate, in each of which 300 mΐ PBS were presented per well. First, rinsing was done by pipetting the PBS 10 times up and down. Thereafter, the test pieces were transferred to a third sterile microtiter plate, again with 300 ml of sterile PBS, using sterile forceps for each piece. After 10 minutes, shake the plate vigorously

Microplate reader, the samples were again transferred to a fourth microtiter plate containing 200 ml sterile PBS

supplemented with 1% fresh TSB, with sterile tweezers again being used for each sample transfer sample. By incubating the 96-well microtiter plate at 37 ° C for 18 to 20 hours, remaining adherent cells could proliferate on the surfaces and release clonal counterparts into the well or were killed by the antimicrobial surface.

After separation of the samples, the released bacteria were amplified by adding 50 mΐ TSB medium per wave for 48 h. The proliferation of the released daughter cells became online at a wavelength of 578 nm

Microplate reader (Synergy 2, BioTek Instruments,

Inc., Winooski, VT 05404, USA), using a time-proliferation curve as the test result for each well of the

Microtiter plate was obtained.

For each growth curve, the time was taken to be an optical one

Density (OD) of 0.2, defined as onset OD time. The more living cells remained on the rubber surface, the more clonal bacteria were released into the surrounding medium, resulting in faster exponential growth and short onset OD times. Long onset times correlate with a strong antibacterial and antiadherent effect of a rubber material.

For statistical evaluation, all measurements were made 24 times, with mean values for the onset OD time and standard deviations calculated for each material and the negative control. Statistical significance of an anti

Bacterial effect was achieved when the P-value of a non-parametric Mann-Whitney test comparing the median values of the onset OD time distributions of negative controls and samples was calculated to be less than or equal to 5%. For the quantification of the antibacterial effect, the difference between the mean onset OD times of the samples and the controls is calculated as Atonset OD. At _on set OD values from 5 hours are considered by medical device manufacturers as characteristic of good antibacterial materials.

Claims

claims

1. containing hydrogen peroxide-silicone adducts

(A) urea-functional organopolysiloxanes of units of the formula (I)

RnSi-0 (4-n) / 2 (I)

in which

R is a radical R ¹ or a radical -OR ² or a radical Q, where

R ^{1 is} a monovalent optionally halogenated

Hydrocarbon radical having 1 to 18 carbon atoms

means

R ^{2 represents} a hydrogen atom or a monovalent C _{1 -C 6} hydrocarbon radical,

Q is a urea-functional radical of the formula (II)

R ⁵ - [NR ⁴ -R ⁶ -] _X NR ⁴ R ³ (II),

in which

R ^{3 represents} a hydrogen atom or a monovalent C _{1 -C 6} hydrocarbon radical, preferably a hydrogen atom,

R ⁴ 'denotes a hydrogen atom or a monovalent C _{1 -C 6} hydrocarbon radical,

R ^{u is} a radical of formula (III)

-C (= O) -NH ₂ (III)

R ^{5 is} a divalent C 1 -C 6 -hydrocarbon radical,

preferably a divalent C 2 -C 4 -hydrocarbon radical, R ⁶ denotes a divalent C 1 -C 6 -hydrocarbon radical, preferably a bivalent C 2 -C 4 -hydrocarbon radical,

x is 0, 1 or 2 and

n is 0, 1, 2 or 3 and preferably

average 2.00 to 2.66,

with the proviso that in the organopolysiloxanes from units of the formula (I) at least one

urea-functional radical Q, which has a radical R ^u , is contained per molecule,

and

(B) hydrogen peroxide.

2. hydrogen peroxide-silicone adducts according to claim 1, characterized in that they consist of

(A) urea-functional organopolysiloxanes

Units of the formula (I) and

(B) hydrogen peroxide.

3. hydrogen peroxide-silicone adducts according to claim 1 or 2, characterized in that in the urea-functional organopolysiloxanes from units of the formula (I)

at least 50% of all radicals R is a Ci_C ₆ alkyl radical R ¹

mean,

at least 0.1% of all radicals R is a radical Q of the formula (II), where in at least one radical Q at least one radical R ^{4 has} the meaning of R ^u , and

at most 3% of all radicals R is a radical -OR ² , where Q, R, R ¹ , R ² , R ⁴ and R ^{u have} the meaning given in claim 1.

4. Hydrogen peroxide-silicone adducts according to claim 1, 2 or 3, characterized in that the urea-functional organopolysiloxanes from units of the formula (I) contain at least 3 Si atoms and at most 2000 Si atoms.

5. hydrogen peroxide-silicone adducts according to one of claims 1 to 4, characterized in that the

urea-functional organopolysiloxanes from units of the formula (I) organopolysiloxanes of the formula (IV)

Q _k R * 3-kS iO (R ¹ ₂ S iO) _m (QR * S iO) pS iR * 3-kQk (IV) where

R * is a radical R ¹ or a radical -OR ² ,

R ¹ and R ² are as defined above,

Q is a urea-functional radical of the formula (II)

R ⁵ - [NR ⁴ -R ⁶ -] _X NR ⁴ R ³ (II),

in which

R ^{3 is} a hydrogen atom or a monovalent Oi-Oe hydrocarbon radical, preferably one

Hydrogen atom,

R ^{4 is the} same or different and a radical R ⁴ 'or

a radical R ^u means where

R ⁴ 'represents a hydrogen atom or a monovalent Oi-Oe hydrocarbon radical and

R ^{u is} a radical of formula (III)

-C (= O) -NH ₂ (III),

R ^{5 is} a divalent C 1 -C 6 -hydrocarbon radical,

preferably a divalent C 2 -C 4 -hydrocarbon radical, R ^{6 is} a divalent C ¹ -C ⁶ -hydrocarbon radical,

preferably a divalent C 2 -C 4 -hydrocarbon radical,

k is 0 or 1,

m is 0 or an integer from 1 to 1000,

p is 0 or an integer from 1 to 50 and

x is 0, 1 or 2,

6. hydrogen peroxide-silicone adducts according to one of claims 1 to 5, characterized in that the urea

functional radicals Q of the formula (II) those of the formula -CH 2 -CH 2 -CH ₂ -NH-C (= O) -NH ₂ ,

-CH 2 -CH 2 -CH ₂ -NH ₂ -CH 2 -CH ₂ -NH-C (= O) -NH ₂ ,

-CH ₂ -CH ₂ -CH ₂ -NH [-c (= O) -NH ₂ ] -CH ₂ -CH ₂ -NH ₂

are .

7. hydrogen peroxide-silicone adducts according to one of claims 1 to 6, characterized in that they have a content of hydrogen peroxide of 0.2 to 20 wt .-%, based on the total weight of the hydrogen peroxide-silicone adducts.

8. A process for preparing the hydrogen peroxide-silicone adducts by reacting the

(A) urea-functional organopolysiloxanes according to one of claims 1 to 7 with (B) hydrogen peroxide.

9. The method according to claim 8, characterized in that hydrogen peroxide is used in pure form or dissolved in water or dissolved in an organic solvent.

10. The method according to claim 8 or 9, characterized in that as organic solvents linear, branched or cyclic alkanes or alkylaromatics or linear or branched alkyl, cycloalkyl or aryl esters of saturated carboxylic acids are used, which have a total of not more than 10 carbon atoms and form an azeotrope with water.

11. Use of the hydrogen peroxide-silicone adducts after

one of claims 1 to 7 or prepared according to claim 8, 9 or 10 in products, preferably pharmacological or cosmetic products, for the award of

antimicrobial properties.

12. Use of the hydrogen peroxide-silicone adducts

one of claims 1 to 7 or prepared according to claim 8, 9 or 10 for bleaching of skin, hair and teeth.

13. Use of the hydrogen peroxide-silicone adducts

one of claims 1 to 7 or prepared according to claim 8, 9 or 10 for wound disinfection.