EP2804896A1

EP2804896A1 - Silane-cross-linking expandable mixtures

Info

Publication number: EP2804896A1
Application number: EP13701004.7A
Authority: EP
Inventors: Volker Stanjek; Lars Zander
Original assignee: Wacker Chemie AG
Current assignee: Wacker Chemie AG
Priority date: 2012-01-20
Filing date: 2013-01-15
Publication date: 2014-11-26
Also published as: WO2013107744A1; DE102012200790A1

Abstract

The invention relates to expandable and cross-linkable masses containing (A) 100 parts by weight of compounds (A) of formula Y - [ (CR¹ _2)b-SiR_a(OR²) _3-a]_x (I), (B) more than 1 part by weight of silicone resins containing units of formula R³ _c(R⁴O)_dR⁵ _eSiO_(4-c-d-e) _/2 (II), and (C) more than 1 part by weight of a propellant that is gaseous at 20°C and 1000 hPa; a pressurised canister containing the expandable and cross-linkable masses; the use of the expandable and cross-linkable masses as single-component sprayable assembly foams; the use of the expandable and cross-linkable masses as one component in two-component sprayable assembly foams; and a hardened expanded article produced from the expandable and cross-linkable masses.

Description

Silane-crosslinking foamable mixtures

The invention relates to silane-crosslinkable foamable mixtures comprising prepolymers, silicone resins and blowing agents, printing cans containing the foamable and crosslinkable compositions, use of the foamable and crosslinkable compositions as one-component sprayable assembly foams or as a component in sprayable two-component foams and hardened foam body, made from the foamable and cross-linkable materials.

Sprayable mounting foams are used to fill cavities, especially in the construction sector. Here you will u.a. for sealing joints, e.g. used for windows and doors, where they lead to excellent thermal insulation as excellent insulating materials. Other applications include the isolation of pipelines or the foaming of cavities in structures or technical equipment.

Conventional assembly foams are so-called polyurethane foams (PU foams), which in the uncrosslinked state consist of prepolymers which have a high concentration of free isocyanate groups. These isocyanate groups are capable of undergoing addition reactions with suitable reactants even at room temperature, whereby hardening of the spray foam after application is achieved. The foam structure is thereby generated by the incorporation of a volatile blowing agent in the uncrosslinked raw material and / or by carbon dioxide, the latter being formed by a reaction of isocyanates with water. The spreading of the foam is usually done from pressure cans by the autogenous pressure of the propellant. Alcohols having two or more OH groups - especially branched and unbranched polyols - or else water serve as reactants for the isocyanates. The latter reacts with isocyanates under the already mentioned release of carbon dioxide to primary amines, which can then add directly to another, still unused isocyanate group. The result is urethane or urea units, which can form semi-crystalline substructures due to their high polarity and their ability to form hydrogen bonds in the cured material and thus lead to foams having high hardness, compression and tear resistance.

The blowing agents used are usually gases which are condensable even at relatively low pressure and can thus be added to the prepolymer mixture in the liquid state without the spray cans having to be exposed to excessively high pressures. Furthermore, the prepolymer blends contain further additives such as e.g. Foam stabilizers, emulsifiers, flame retardants, plasticizers and catalysts. The latter are usually organic tin compounds or tertiary amines.

PU spray foams are produced both as so-called one-component (1K) and as two-component (2K) foams. The 1K foams cure exclusively by the contact of the isocyanate-containing prepolymer mixture with the humidity. The carbon dioxide released in the 1K foams during the curing reaction can also promote foaming. 2K foams contain an isocyanate component and a polyol component, which must be mixed together well before foaming and hardened by the reaction of the polyol with the isocyanates. The advantage of the 2K systems is a short curing time of sometimes only a few minutes up to a full curing. However, they have the disadvantage that they require a more complicated pressure cell with two chambers and are also much less comfortable to handle than the 1K systems.

The cured PU foams are characterized above all by their excellent mechanical and heat-insulating properties. Furthermore, they have very good adhesion to most substrates and are highly durable under dry and UV-protected conditions. Further advantages are the toxicological safety of the cured foams as soon as all isocyanate units are quantitatively reacted, as well as their rapid curing and their ease of handling. Due to these properties, PU foams have proven very successful in practice.

However, conventional PU spray foams have the critical disadvantage that they have a relatively large content of free monomeric isocyanates in the uncrosslinked state, which are toxicologically extremely questionable. In particular, the MDI (diisocyanatodiphenylmethane), which is contained in almost every conventional PU foam, is now suspected of being carcinogenic. Foamable mixtures containing more than 1% free MDI should therefore be labeled with a reference to a possible carcinogenic effect. In some

Countries such as France and Germany are also leading to sales restrictions in the DIY segment. Furthermore, all isocyanates also have a very strong sensitizing effect, i.a. they can trigger asthma attacks.

In addition to the direct contact of the prepolymer mixture with the skin, a critical factor here is also possible aerosol formation during the application of the foam or the evaporation of low molecular weight constituents, eg of monomeric isocyanates. As a result, there is the danger that toxicologically harmful compounds are absorbed via the respiratory air. These risks are exacerbated by the fact that the PU spray foams are often not used by professional users but by inexperienced do-it-yourselfers, which is why proper handling can not always be assumed.

In order to overcome these disadvantages, sprayable assembly foams have come on the market in the past 1-2 years, although they still cure via the reactions of isocyanate groups, but contain only a very small proportion of free monomeric isocyanates. The aim of these products is in particular the avoidance of a labeling obligation with regard to a possibly carcinogenic effect. The contents of monomeric isocyanates are therefore below 1%, z.T. even below 0.1%. However, these low levels relate only to the monomeric isocyanates. The content in isocyanate group is still very high in these products as well. Instead of monomeric isocyanates, the corresponding foams now contain large amounts of short-chain polymeric isocyanates. Thus, these products are toxicologically by no means harmless, especially here is to assume a strong sensitizing effect.

Spray foam systems, which dispense entirely with isocyanate hardening, are therefore even cheaper. The most important product group here are silane-crosslinking foams, such as e.g. in US 20040072921 A, US 20060189705 A, or US 20110224319 A are described. These are typically around

Foams based on prepolymers prepared from polyether polyols, diisocyanates and aminoalkylalkoxysilanes such as N-phenylaminomethyl-methyldimethoxysilane. If, in the preparation of these prepolymers, the stoichiometries are selected so that all isocyanate groups react, isocyanate-free prepolymers are obtained whose chain ends are terminated with alkoxysilyl groups. The latter, with suitable catalysis, can react with atmospheric moisture to form siloxane bridges, ultimately curing the foams. Silane-crosslinking spray foams are now commercially available. However, despite all the toxicological advantages, silane-crosslinking foams have the disadvantage of requiring a very high concentration of crosslinkable groups. The amount of aminoalkylalkoxysilanes which must be used in the preparation of the corresponding prepolymers is correspondingly high. Since the aminosilanes usually represent the most expensive raw material types, the resulting products are correspondingly expensive. By contrast, if significantly lower silane contents are used, a foam is obtained which is too soft for many applications.

The invention relates to foaming and crosslinkable compositions containing

(A) 100 parts by weight of compounds (A) of the formula Y- [(CR ¹ ₂ ) b -SiR _a (OR ² ) 3- _a ] _x (I) where

Y denotes an x-valent polymer radical bound via nitrogen, oxygen, sulfur or carbon,

R can be the same or different and represents a monovalent, ge ^¬ optionally substituted, SiC-bonded hydrocarbon radical, R ^{1 may be} identical or different and represents hydrogen atom or a monovalent, optionally substituted hydrocarbon radical which may be attached to the carbon atom via nitrogen, phosphorus, oxygen, sulfur or carbonyl group,

R ^{2 may be} identical or different and represents hydrogen atom or a monovalent, optionally substituted hydrocarbon radical,

x is an integer from 1 to 10, preferably 1, 2 or 3, particularly preferably 1 or 2,

a may be the same or different and is 0, 1 or 2, preferably 0 or 1, and

b may be identical or different and is an integer from 1 to 10, preferably 1, 3 or 4, particularly preferably 1 or 3, in particular 1,

(B) more than 1 part by weight of silicone resins containing units of the formula

R ³ _c (R ⁴ O) _d R ⁵ _e SiO _(4- cde) / 2 (II) where

R ^{3 may be} identical or different and is hydrogen, a monovalent, SiC-bonded, optionally substituted aliphatic hydrocarbon radical or a divalent, optionally substituted, aliphatic hydrocarbon radical bridging two units of the formula (II),

R ^{4 may be the} same or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical, R ^{5 may be the} same or different and is a monovalent, SiC-bonded, optionally substituted aromatic hydrocarbon radical,

c is 0, 1, 2 or 3,

d is 0, 1, 2 or 3, preferably 0, 1 or 2, more preferably 0 or 1, and

e is 0, 1 or 2, preferably 0 or 1, with the proviso that the sum of c + dse is less than or equal to 3 and in at least 40% of the units of formula (II) the sum c + e is 0 or 1 is, and

C) more than 1 part by weight of a propellant gaseous at 20 ° C and 1000 hPa.

The foamable and crosslinkable compositions increase the hardness of silane-crosslinking spray foams without having to use prepolymers with an increased density of alkoxysilyl groups.

Examples of radicals R are alkyl radicals, such as the methyl, ethyl, n-propyl, iso-propyl, 1-n-butyl, 2-n-butyl, iso-butyl, tert. Butyl, n-pentyl, iso-pentyl, neo-pentyl, tert-penyl 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, iso-octyl radicals and the 2, 2, 4-trimethylpentyl radical; Nonyl radicals, such as the n-nonyl radical; Decyl radicals, such as the n-decyl radical; Dodecyl radicals, such as the n-dodecyl radical; Octadecyl radicals, such as the n-octadecyl radical; Cycloalkyl radicals such as the cyclopentyl, cyclohexyl, cycloheptyl and methylcyclohexyl radicals; Alkenyl radicals, such as the vinyl, 1-propenyl and the 2-propenyl radical; Aryl radicals, such as the phenyl, naphthyl, anthryl and phenanthryl radicals; Alkaryl radicals, such as o-, m-, p-tolyl radicals; Xylyl radicals and ethylphenyl radicals; and aralkyl radicals, such as the benzyl radical, the - and the .beta.-phenylethyl radical. Examples of substituted radicals R are haloalkyl radicals, such as the 3, 3, 3-trifluoro-n-propyl radical, the 2, 2, 2 ", 2", 2'-hexafluoroisopropyl radical and the heptafluoroisopropyl radical, and haloaryl radicals, such as the o-, m- and p-chlorophenyl.

The radicals R are preferably monovalent hydrocarbon radicals having 1 to 6 carbon atoms which are optionally substituted by halogen atoms, more preferably alkyl radicals having 1 or 2 carbon atoms, in particular the methyl radical.

Examples of radicals R ¹ are hydrogen atom, the radicals indicated for R and optionally substituted hydrocarbon radicals bonded to the carbon atom via nitrogen, phosphorus, oxygen, sulfur, carbon or carbonyl group.

Radical R ¹ is preferably hydrogen atom and hydrocarbon radicals having 1 to 20 carbon atoms, in particular hydrogen atom.

Examples of radical R ² are hydrogen atom or the examples given for radical R.

The radicals R ^{2 are} preferably hydrogen atoms or alkyl radicals having 1 to 10 carbon atoms optionally substituted by halogen atoms, more preferably alkyl radicals having 1 to 4 carbon atoms, in particular the methyl and ethyl radical. The polymer radical Y preferably contains organic polymer radicals whose polymer chain is selected from the polymer chain of polyesters, polyurethanes, polyoxyalkylenes, hydrocarbon polymers, polyamides, polyacrylates, polymethacrylates, polycarbonates and theirs Mixtures and preferably via -OC (= O) -NH-, -NH-C (= O) O-, -NH-C (= O) -NH-, -NR'-C (= O) -NH- , NH-C (= O) -NR '-, -NH-C (= O) -,

-C (= O) -NH-,

-C (= O) -O-, -O-C (= O) -, -O-C (= O) -O-, -S-C (= O) -NH-, -NH-C (= 0) -S-, -C (= O) -S-, -SC (= O) -, -SC (= O) -S-, -C (= O) -, -S-, -O- and -NR '- to the group or groups - [(CR ¹ ₂ ) _b -SiR _a (OR ² ) _3-a ] are bonded, where R' may be identical or different and has a meaning given for R or for a Group -CH (COOR ") -CH ₂ -C00R", in which R "may be identical or different and has a meaning given for R.

Examples of radicals R 'are cyclohexyl, cyclopentyl, n- and iso-propyl, n-, iso- and t-butyl, the various steroid isomers of the pentyl radical, hexyl radical or heptyl radical and also the phenyl radical.

The radical R 'is preferably a group

-CH (C00R ') -CH ₂ -C00R' or an optionally substituted hydrocarbon radical having 1 to 20 carbon atoms, more preferably a linear, branched or cyclic Alkylgrup- pe having 1 to 20 carbon atoms or an optionally substituted by halogen atoms, aryl group having 6 to 20 carbon atoms. The radicals R "are preferably alkyl groups having 1 to 10 carbon atoms, particularly preferably methyl, ethyl or propyl radicals.

Particularly preferably, radical Y in formula (I) is polyurethane radicals and polyoxyalkylene radicals, in particular polyoxyalkylene or polyester-containing polyurethane radicals or polyoxyalkylene radicals. The compound (A) may be the connected in the manner described groups - have [(CR) _b ~ SiR _a (OR ²⁾ _3-a] at any point in the polymer, such as chain positions and / or terminal, preferably chain positions and terminally , especially terminal.

The end groups of the compounds (A) used according to the invention are preferably those of the general formulas and -NH-C (= O) -NR '- (CR ¹ ₂ ) _b -SiR _a (OR ² ) 3 - _a (IV), where the radicals and indices have any of the meanings given above. The average molecular weights M _n (number average) of the compounds (A) are preferably at least 400 g / mol, more preferably at least 600 g / mol, and preferably at most 20,000 g / mol, more preferably at most 10,000 g / mol, in particular at most 5 000 g / mol.

The viscosity of the compounds (A) is preferably at least 30 Pas, preferably at least 100 Pas, more preferably at least 300 Pas, and preferably at most 5000 Pas, preferably at most 2000 Pas, each measured at 20 ° C.

The compounds (A) used according to the invention are commercially available products or can be prepared by methods customary in chemistry. The preparation of the compounds (A) can be carried out by various known processes, such as addition reactions such as hydrosilylation, Michael addition, Diels-Alder addition or reactions between isocyanate-functional compounds with compounds having isocyanate-reactive groups.

In a particularly preferred embodiment of the invention, the compound (A) contains polymer radicals Y as linear or branched polyurethane radicals, the preparation of which is preferably based on polyether and / or polyester polyols Yl having an average molar mass of from 200 to 20,000 daltons. In this case, polyether polyols, in particular polypropylene glycols, having an average molecular weight M _{n of} from 300 to 6,000 daltons, in particular from 350 to 4,500 daltons, are particularly preferably used. In a particular embodiment of the invention, the polyols Y1 are, at least in part, halogenated polyols, for example halogen-containing polyethers. Halogenated polyols have the advantage that they lead to products with better fire properties. The polyols Y1 can be branched or unbranched. Particularly preferred are unbranched polyols or polyols with a branch point. It is also possible to use mixtures of branched and unbranched polyols.

In the preparation of component (A), the polyols Y1 are preferably reacted with at least one isocyanate-functional compound Y2. Preferably, Y 2 is di-or polyisocyanates. Examples of common diisocyanates are diisocyanatodiphenylmethane (MDI), both in the form of crude or technical MDI and in the form of pure 4,4 'or 2,4' isomers or mixtures thereof, tolylene diisocyanate (TDI) in the form of its various regioisomers, diisocyanato naphthalene (NDI), isophorone diisocyanate (IPDI) or hexamethylene diisocyanate (HDI). Examples of polyisocyanates are polymeric MDI (P-MDI), Triphenylmethantriisocanat or Triraerisate

(Biurethe or isocyanurates) of the above diisocyanates.

Particular preference is given to using p-MDI, MDI or TDI, in particular MDI or TDI. The isocyanates Y2 can in this case with respect to the ratio of the isocyanate groups to the hydroxyl groups of the polyol in the deficit (variant 1) or in excess (variant 2) are used. In variant 1, a polyurethane polymer is obtained whose chain ends are terminated with hydroxyl groups, in variant 2 a polymer whose chain ends consists of isocyanate groups. The hydroxyl-functional polyurethane polymer obtained in variant 1 is then preferred with a silane Y 3 of the general formula

OCN- (CR ¹ ₂ ) _b -SiR _a (OR ²⁾ ₃ - _a ⁽ V) reacted, wherein the radicals and indices have one of the meanings given above. There is obtained a polyurethane with chain ends of the formula (III). Examples of compounds of the formula (V) are isocyanatomethyl-methyldimethoxysilane, isocyanatomethyltrimethoxysilane, isocyanatomethyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane or 3-isocyanatopropyltriethoxysilane. Isocyanatomethylmethyldimethoxysilane or 3-isocyanatopropyltrimethoxysilane are preferred.

However, variant 2 is particularly preferred. The resulting isocyanate-functional polyurethane polymer is then preferred in a second reaction step with an isocyanate-reactive silane Y3 'of the general formula implemented, where

Z represents an isocyanate-reactive group and all other radicals and indices have one of the meanings given above.

The isocyanate-reactive group Z is preferably a hydroxyl group or an amino group, particularly preferably an amino group of the formula NHR 'having' 'having one of the abovementioned meaning. This gives a silane-terminated polyurethane having chain ends of the formula (IV).

Examples of compounds of the formula (VI) are phenylaminomethyl-methyldimethoxysilane, phenylaminomethyltrimethoxysilane, N-cyclohexylaminomethyl-methyldimethoxysilane, N-cyclohexy-1-aminomethyltrimethoxysilane. W-butylaminomethyl-1-methyldimethoxysilane, N-butylaminomethyltrimethoxysilane, 3-phenylaminopropylmethyldimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3- (N-cyclohexylamino) -propylmethyldimethoxysilane, 3- (N-cyclohexylamino) - propyl-trimethoxysilane. 3- (N-butylamino) -propyl-methyldimethoxysilane, 3 - (N-butylamino) propyltrimethoxysilane and all derivatives of said silanes in which some or all of the silicon-bonded methoxy groups are replaced by ethoxy groups. Finally, in addition to the abovementioned components Y1 to Y3 or Y3 ', it is also possible to use monomeric alcohols Y4 component in the preparation of the compound (A). The alcohols Y4 can be converted via one or more hydroxyl groups. put. With regard to the molecular weight and the degree of branching of the alcohols Y4, there are preferably no restrictions.

If alcohols Y4 are used to prepare the compounds (A), they are preferably those of the general formula

R ⁶ OH (VII), wherein R ^{6 has} one of the meanings given for the radical R.

The radical R ⁶ is preferably a linear, branched or branched alkyl or alkenyl radical having at least 8 carbon atoms, linear alkyl radicals having at least 8 carbon atoms, in particular linear alkyl radicals having at least 10 carbon atoms, being particularly preferred. Preferably, R ^{6 has} at most 30, more preferably at most 22, carbon atoms. These alcohols can also react with the di- or polyisocyanates Y2. This results in compounds (A) whose chain ends are not terminated exclusively with chain ends of the formula (IV), but also over a certain proportion, preferably at least 2%, more preferably at least 4% and preferably at most 40%, in particular at most 20% Chain ends of the general formula

-NH-C (= O) -O-R ⁶ (VIII) in which R has the abovementioned meanings.

The alcohols Y4 may have been incorporated into the component (A) in a separate reaction step, for example before or after the reaction of the polyols Yl with the isocyanates Y2. Alternatively, however, the incorporation can also take place simultaneously with another reaction step, for example by reacting a mixture of the polyols Y.sub.1 and the alcohols Y.sub.4 with the isocyanates Y.sub.2.

Alcohols Y.sub.4, mixtures of different alcohols Y.sub.4 or else mixtures of polyols Y.sub.1 and alcohols Y.sub.4 are preferably used which are liquid at room temperature and the pressure of the surrounding atmosphere, ie at 900 to 1100 hPa, and are accordingly simply metered into the reaction mixture can.

The sequence of the synthesis steps is in principle also exchangeable. Thus, the first synthesis step can in principle also consist of a reaction of the isocyanate Y 2 with the silane Y 3 'and the reaction with the polyol Y 1 take place only in the second reaction step. It is also conceivable to carry out both reaction steps simultaneously.

All reactions for the preparation of component (A) can be carried out either batchwise or continuously. If appropriate, the preparation of components (A) is carried out in the presence of a catalyst. Suitable catalysts are, for example, the bismuth-containing catalysts, e.g. of the

Borchi ^® Kat 22, borchi ^® Kat VP 0243, borchi ^® Kat VP 0244 from Messrs. Borchers GmbH or those compounds which inhibit the curable compositions of the invention as curing catalysts (E) may be added. The preparation of the components (A) is preferably carried out at temperatures of at least 0 ° C, more preferably at least 60 ° C and preferably at most 150 ° C, in particular at most 120 ° C.

Preferably, all components for the preparation of the compounds (A) are used in a quantitative ratio, according to which 1 isocyanate group preferably at least 0.6, more preferably at least 0.8 and preferably at most 1.4, in particular at most 1.2 isocyanate-reactive groups ,

The compounds (A) are preferably isocyanate-free. The freedom from isocyanate can also be achieved if a slight excess of NCO groups based on the NCO-reactive groups is used, because the excess NCO groups are e.g. can also react with formed urethane and / or urea units under allophanate or Biurethbildung. In a particularly preferred method, the compound

(A) prepared in the presence of the silicone resin component (B). In this case, all reaction steps or only the last or the last reaction steps in the presence of component (B) can be carried out. The addition of component (B) already during the production process of component (A) has the advantage that the usually low-viscosity component (B) dilutes the usually very high-viscosity component (A) and thus significantly facilitates its further processing. Furthermore, it may be advantageous to prepare the compound (A) not in separate systems but directly in the foam can. In this case, all the reaction steps or else only the last reaction step (s) in the foam can are carried out. be led. Such a method would have the advantage that no further transfer or refilling operations with the often comparatively high-viscosity component (A) are necessary.

Of course, in such a (partial) synthesis in the foam can already be the components (B) present.

The component (A) used according to the invention may contain only one type of compound of the formula (I) as well as mixtures of different types of compounds of the formula (I). In this case, component (A) may contain exclusively compounds of the formula (I) in which more than 90%, preferably more than 95%, particularly preferably more than 98%, of all the silyl groups bound to the polymer radical Y are identical. However, it is then also possible to use a component (A) which contains, at least in part, compounds of the formula (I) in which different silyl groups are bound to a polymer radical Y. Finally, as component (A) it is also possible to use mixtures of different compounds of the formula (I) in which a total of at least 2 different types of silyl groups are present, but all of the silyl groups bound to one polymer radical Y are identical.

If component (A) is a different type of compound of formula (I), mixtures are those containing both compounds (AI) having end groups of formula (III) or (IV) in which b = 1 and R ¹ = H and a = 0 or 1, as well as compounds (A2) having end groups of the formula (IV) or (V) in which b = 3 and R ¹ = H and a = 0, are preferred and those particularly preferred in which the weight ratio of (AI) to (A2) 0.1 to 10, preferably 0.2 to 5, is. In principle, polymers as described in the descriptions, but in particular also in the examples of US 20040072921 A, US 20060189705 A, or US 20110224319 A, are suitable as components (A).

The foamable and crosslinkable compositions preferably contain compounds (A) in concentrations of at most 90% by weight, more preferably at most 70% by weight, and preferably at least 10% by weight, particularly preferably at least 15% by weight.

Based on 100 parts by weight of component (A), the foamable and crosslinkable compositions preferably contain at least 10 parts by weight, more preferably at least 30 parts by weight, and preferably at most 1000 parts by weight, more preferably at most 500 parts by weight, especially at most 300 parts by weight, component (B) ,

Component (B) is preferably at least 90% by weight of units of the formula (II). Component (B) particularly preferably consists exclusively of units of the formula (II).

Examples of radicals R ³ are the aliphatic radicals given above for R. However, radical R ³ may also be divalent aliphatic radicals which connect two silyl groups of the formula (II) with one another, for example alkylene radicals having 1 to 10 carbon atoms, such as methylene, ethylene, propylene or butylene radicals. A particularly common example of a divalent aliphatic radical is the ethylene radical. However, radical R ³ is preferably monovalent SiC-bonded aliphatic hydrocarbon radicals having 1 to 18 carbon atoms which are optionally substituted by halogen atoms, particularly preferably aliphatic hydrocarbon radicals. radicals having 1 to 6 carbon atoms, in particular the methyl radical.

Examples of radical R ⁴ are hydrogen atom or the examples given for radical R.

Radical R ⁴ is preferably hydrogen or optionally halogen-substituted alkyl radicals having 1 to 10 carbon atoms, more preferably alkyl radicals having 1 to 4 carbon atoms, in particular the methyl, ethyl or butyl radical.

Examples of radicals R ⁵ are the aromatic radicals given above for R.

Radical R ⁵ is preferably SiC-bonded aromatic hydrocarbon radicals having 1 to 18 carbon atoms, optionally substituted by halogen atoms, such as, for example, ethylphenyl, toluyl, xylyl, chlorophenyl, naphthyl or styryl radicals, particularly preferably to the phenyl radical.

Silicone resins are preferably used as components (B) in which at least 90% of all radicals R ^{3 is} methyl, at least 90% of all radicals R ^{4 is} methyl, ethyl, propyl, Isopro- pyl- or butyl radical and at least 90% of all Radicals R ^{5 are} phenyl.

Silicone resins (B) which have at least 20%, particularly preferably at least 40%, in particular at least 60%, of units of the formula (II) in which c is 0, in each case based on the total number of units of the formula, are preferably used (II). In one embodiment of the invention, silicone resins (B) are used which, based in each case on the total number of units of the formula (II), are at least 10%, particularly preferably at least 20%, and at most 80%, particularly preferably at most 60%. have units of the formula (II) in which c is 2 or greater than 2. In a particular embodiment of the invention, silicone resins (B) are used which do not have units of the formula (II) in which c has the value 2 or greater than 2.

Silicone resins (B) are preferably used which, based in each case on the total number of units of the formula (II), have at least 80%, particularly preferably at least 95%, of units of the formula (II) in which d is 0 or 1 stands.

Silicone resins (B) are preferably used which, based in each case on the total number of units of the formula (II), have at least 60%, particularly preferably at least 70%, preferably at most 99%, particularly preferably at most 97%, units of the formula (II) in which d stands for the value 0.

It is preferred to use silicone resins as components (B) which, based in each case on the total number of units of the formula (II), have at least 20%, preferably at least 40%, in particular at least 60% of units of the formula (II) in which e is a value is not equal to 0. It is even possible to use silicone resins (B) which contain exclusively units of the formula (II) in which e is not 0. All units of the formula (II) which have an e not equal to 0 preferably have a value of 1 for e.

Silicone resins (B) are preferably used which, based in each case on the total number of units of the formula (II), at least 50%, in particular at least 70%, of units of the formula (II) in which the sum c + e is 0 or 1.

In a particularly preferred embodiment of the invention, component (B) used are silicone resins which, based in each case on the total number of units of the formula (II), have at least 20%, particularly preferably at least 40%, in particular at least 60%, units of the formula (II) II), in which e stands for the value 1 and c stands for the value 0. Preferably, at most 70%, particularly preferably at most 40% of all units of the formula (II) have a d not equal to 0.

In a further particularly preferred embodiment of the invention, component (B) used are silicone resins which, in each case based on the total number of units of the formula

(II), at least 20%, particularly preferably at least 40%, in particular at least 60%, of units of the formula (II) in which e is the value 1 and c is the value 0 and which moreover at least 1%, preferably at least 10%, of units of the formula (II) in which c is 1 or 2, preferably 2, and e is 0. Preferably, at most 70%, particularly preferably at most 40%, of all units of the formula (II) have a d not equal to 0 and at least 1% of all units of the formula (II) have a d of 0.

Examples of the inventively used silicone resins (B) are organopolysiloxane resins which are substantially, preferably exclusively, from (Q) units of the formula Si0 _{_4/2}

Si (OR ⁴⁾ ₂ 0 _3, Si (OR ⁴⁾ ₂ 0 _{_2/2} and Si (OR ⁴⁾ ₃ 0 _1/2 (T) units of my research PhSi0 _3/2, PhSi (OR ⁴⁾ 0 _2/2 and PhSi (OR ⁴⁾ ₂ 0i / _2, (D) units of the formula Me ₂ Si0 _{_2/2} and Me ₂ Si (OR ⁴⁾ Oi / ₂ and (M) units of the formula Me ₃ SIOI / ₂ , wherein Me is a methyl radical, Ph is a phenyl radical and R ^{4 is} hydrogen or optionally halogeno-substituted alkyl radicals having from 1 to 10 carbon atoms, more preferably hydrogen or alkyl radicals having from 1 to 4 carbon atoms, the resin preferably having from 0 to 2 mol (Q) units, 0 to 2 moles per mole of (T) units. D) units and 0-2 mol (M) units.

Preferred examples of the inventively used silicone resins (B) are organopolysiloxane resins that are substantially, preferably exclusively, of T units of the formulas PhSi0 _3/2, PhSi (OR ⁴⁾ 0 _2/2 and PhSi (OR ⁴⁾ ₂ 0i _{/ 2} and D units of the formulas Me ₂ Si0 _2/2 and Me ₂ Si (OR ⁴ ) Oi _{/ 2} , where Me is a methyl radical, Ph is a phenyl radical and R ^{4 is} hydrogen atom or optionally halogen atoms substituted with 1 to 10 alkyl radicals Carbon atoms, particularly preferably hydrogen atom or alkyl radicals having 1 to 4 carbon atoms, with a molar ratio of (T) to (D) units of 0.5 to 2.0.

Further preferred examples of the silicone resins (B) used according to the invention are organopolysiloxane resins which consist essentially, preferably exclusively, of T units of the formulas PhSiO _3/2 , PhSi (OR ⁴ ) O _2/2 and PhSi (OR ⁴ ) ₂ 0i _{/ 2} and T-A ^¬ units of the formulas MeSi0 _3/2 MeSi (OR ⁴⁾ 0 _2/2 and MeSi (OR ⁴⁾ 2O1 / 2, and optionally D units of the formula Me ₂ Si0 _2/2 and

Me ₂ Si (OR ⁴ ) Oi _{/ 2} , wherein Me is a methyl radical, Ph is a phenyl radical and R ^{4 is} hydrogen or optionally substituted by halogen atoms substituted alkyl radicals having 1 to 10 carbon atoms, more preferably hydrogen or alkyl radicals having 1 to 4 carbon atoms , with a molar ratio of phenylsilicone to methyl silicone units of 0.5 to 4.0. The content of D units in these silicone resins is preferably less than 10% by weight. Additional preferred examples of the inventively used silicone resins (B) are organopolysiloxane resins that are substantially, preferably exclusively, of T units of the formulas PhSi0 _{3 2 /} PhSi (OR ⁴⁾ 0 _{_2/2} and PhSi (OR ⁴⁾ ₂ 0i / ₂ where Ph is a phenyl radical and R ^{4 is} hydrogen or optionally substituted by halogen atoms substituted alkyl radicals having 1 to 10 carbon atoms, more preferably hydrogen or alkyl radicals having 1 to 4 carbon atoms. The content of D units in these silicone resins is preferably less than 10% by weight.

The silicone resins (B) used in the foamable and crosslinkable compositions preferably have a mean molecular weight (number average) M _n of at least 400 g / mol and more preferably of at least 600 g / mol. The average molar mass M _n is preferably at most 400 000 g / mol, more preferably at most 100 000 g / mol, in particular at most 50 000 g / mol. The silicone resins (B) used can be both solid and liquid at 23 ° C. and 1000 hPa, silicone resins (B) preferably being liquid. The silicone resins (B) preferably have a viscosity of from 10 to 100,000 mPas, preferably from 50 to 50,000 mPas, in particular from 100 to 20,000 mPas. The silicone resins (B) preferably have a polydispersity (M _w / M _n ) of not more than 5, preferably not more than 3.

The silicone resins (B) can be used both in pure form and in the form of a solution in a suitable solvent.

Substances such as ethers (eg diethyl ether, methyl t-butyl ether, ether derivatives of glycol, THF) can be used as solvent. Esters (for example ethyl acetate, butyl acetate, glycol esters), hydrocarbons (for example pentane, cyclopentane, hexane, cyclohexane, heptane, octane or else long-chain branched and unbranched alkanes), ketones (for example acetone, methyl ethyl ketone), aromatics (for example toluene, Xylene, ethylbenzene, chlorobenzene) or alcohols (eg methanol, ethanol, glycol, propanol, isopropanol, glycerol, butanol, isobutanol, t-butanol).

Preferably, however, silicone resins (B) are used, which are free of organic solvents.

The used silicone resins (B) is ⁽⁰ IC 678 of Messrs. Wacker Chemie AG, Munich, for example SILRES ^@ SY 231, SILRES ^® IC 368 or SILRES) or can be prepared in silicon chemistry methods according to commercial products ,

Based on 100 parts by weight of component (A), the foamable and crosslinkable materials preferably contain at least 10 parts by weight, more preferably at least 20 parts by weight, of blowing agent (C). Based on 100 parts by weight of component (A), the foamable and crosslinkable compositions preferably contain at most 200 parts by weight, more preferably at most 100 parts by weight, in particular at most 80 parts by weight, component (C).

Suitable blowing agents (C) are the same at 20 ° C and 1000 hPa gaseous but especially at relatively low pressures condensable compounds which are also used for the preparation of conventional isocyanate spray foams. Suitable blowing agents are, for example, hydrocarbons having in each case 1-4, in particular 3-4, carbon atoms, fluorohydrocarbons having 1-4 carbon atoms, such as 1, 1, 1, 2-tetracarboxylic fluoroethane, 1, 1-difluoroethane, 1, 1, 1, 2, 3, 3, 3 -heptafluoropropane or dimethyl ether. Often the blowing agent (C) also consists of a mixture of two or more of said components.

In principle, carbon dioxide can also be used as blowing agent (C) or

Part of the propellant (C) can be used.

Hydrocarbons, especially propane, butane, isobutane and propane / butane mixtures, preferably represent the main component of the blowing agent (C). Thus, the blowing agent (C) is preferably at least 50 vol .-%, in particular at least 80 vol .-% Hydrocarbon blowing agents. The blowing agent mixture (C) may well consist of 100% of hydrocarbon propellants, but may also contain other components. As another typical propellant component, the propellant mixture (C) preferably contains dimethyl ether, preferably 0.1-20% by volume, more preferably 0.5-10% by volume. But other known propellants may be present in the propellant mixture (C). All of the above vol .-% figures always add up to 100%.

The latter blowing agents or blowing agent mixtures (C) are preferably used in combination with the types of compound (A) and silicone resins (B) which are described above and which are preferred for use.

In addition to the components (A), (B) and (C) used, the compositions according to the invention may contain all other substances which were hitherto used in silane-crosslinking compositions and / or PU foams and which differ from components (A). , (B) and (C), such as, for example, basic nitrogen-containing organosilicon compound (D), catalyst (E), organo-silicon silicon compound without basic nitrogen (F), fire retardant (G) and additives (H).

Component (D) is preferably organosilicon compounds containing units of the formula

DSi (OR ⁷ ) _g R ⁸ _(3- _g ) (IX) wherein

R ^{7 may be} identical or different and is hydrogen or optionally substituted hydrocarbon radicals, D may be identical or different and represents a monovalent, Sic-bonded radical with basic nitrogen,

R ^{8 may be the} same or different and is a monovalent, optionally substituted Sic-bonded, of basic

Nitrogen free organic residue means

g is 1, 2 or 3, preferably 2 or 3.

In a preferred embodiment of the invention, the foamable and crosslinkable compositions in addition to the components (A), (B) and (C) also contain at least one further component (D) corresponding to the formula (IX), especially if it is at Component (A) is the silane-terminated urethanes with end groups of the formula (IV) which are preferably to be used. It was surprising that when components (A) and (B) are used which are not or poorly soluble in the preferred proportions, it is possible to obtain substantially homogeneous, preferably completely homogeneous mixtures by adding component (D). This advantage obtainable by the use of component (D) is particularly important because the foam obtained by the evaporation of the blowing agent (C) has a significantly better stability, if the remaining components remaining in the foam matrix form a homogeneous solution form. This stability is crucial so that the fine-celled foam structure is retained until the foam has hardened and the foam structure associated therewith is fixed. Examples of optionally substituted hydrocarbon radicals R ⁷ are the examples given for radical R.

The radicals R ⁷ are preferably hydrogen atom and optionally halogen atoms substituted hydrocarbon radicals having 1 to 18 carbon atoms, more preferably hydrogen and hydrocarbon radicals having 1 to 10 carbon atoms, in particular methyl and ethyl radical.

Examples of radical R ⁸ are the examples given for R.

The radical R ⁸ is preferably hydrocarbon radicals optionally substituted by halogen atoms having 1 to 18 carbon atoms, particularly preferably hydrocarbon radicals having 1 to 5 carbon atoms, in particular the methyl radical.

Examples of radicals D are radicals of the formulas H ₂ N (CH ₂ ) ₃ -,

H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -, H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₂ NH (CH ₂ ) ₃ -, H ₃ CNH (CH ₂ ) ₃ -,

C ₂ H ₅ NH (CH ₂ ) ₃ -, C ₃ H ₇ NH (CH ₂ ) ₃ -, C ₄ H ₉ NH (CH ₂ ) ₃ -, C ₅ Hn H (CH ₂ ) ₃ -,

C ₆ H ₁₃ NH (CH ₂ ) ₃ -, C ₇ H ₁₅ NH (CH ₂ ) ₃ -, H ₂ N (CH ₂ ) ₄ -, H ₂ -CH ₂ -CH (CH 3) - CH ₂ -, H ₂ N (CH ₂₎ ₅ -, cyclo-C ₅ H ₉ NH (CH ₂₎ ₃ -, cyclo-C ₃ hunh (CH ₂₎ ₃ -, phenyl, NH (CH ₂₎ ₃ -, (CH ₃₎ ₂ N (CH ₂ ) ₃ -, (C ₂ H ₅ ) ₂ N (CH ₂ ) ₃ -, (C ₃ H ₇ ) ₂ NH (CH ₂ ) ₃ -,

(C ₄ H ₉ ) ₂ NH (CH ₂ ) ₃ -, (C ₅ H ₁₁ ) ₂ NH (CH ₂ ) ₃ -, (C _e H ₁₃ ) ₂ NH (CH ₂ ) ₃ -,

(C ₇ H ₁₅ ) ₂ NH (CH ₂ ) ₃ -, H ₂ N (CH ₂ ) -, H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) -,

H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₂ NH (CH ₂ ) -, H ₃ CNH (CH ₂ ) -, C ₂ H ₅ NH (CH ₂ ) -, C ₃ H ₇ NH (CH ₂ ) -, C ₄ H ₉ NH (CH ₂₎ -, C ₅ HNNH (CH ₂₎ -, C _S H _{X 3} NH (CH ₂₎ -, C ₇ H ₁₅ NH (CH ₂₎ -, cyclo-C ₅ H ₉ NH (CH ₂ ) -, cyclo-C ₆ HnNH (CH ₂ ) -, phenyl-NH (CH ₂ ) -, (CH ₃ ) ₂ N (CH ₂ ) -,

(C ₂ H ₅ ) ₂ N (CH ₂ ) -, (C ₃ H ₇ ) ₂ NH (CH ₂ ) -, (C ₄ H ₉ ) ₂ NH (CH ₂ ) -, (C ₅ H _n ) ₂ NH (CH ₂ ) -, (C ₅ Hi 3) ₂ NH (CH ₂ ) -, (C ₇ H ₁₅ ) ₂ NH (CH ₂ ) (CH ₃ O) ₃ Si (CH ₂ ) ₃ NH (CH ₂ ) ₃ -,

(C ₂ H ₅ O) ₃ Si (CH ₂ ) ₃ NH (CH ₂ ) ₃ -, (CH ₃ O) ₂ (CH ₃ ) Si (CH ₂ ) ₃ NH (CH ₂ ) ₃ - and

(C ₂ H ₅ O) 2 (CH ₃ ) Si (CH ₂ ) ₃ NH (CH ₂ ) ₃ - as well as reaction products of the abovementioned primary amino groups with compounds which contain reactive double bonds or epoxy groups relative to primary amino groups.

Examples of the optionally used silanes of the formula (IX) are H ₂ N (CH ₂ ) ₃ -Si (OCH ₃ ) ₃ ,

H ₂ N (CH ₂ ) 3-Si (OC ₂ H ₅ ) ₃ , H ₂ N (CH ₂ ) ₃ -Si (OCH ₃ ) ₂ CH ₃ ,

H ₂ N (CH ₂ ) ₃ -Si (OC ₂ H ₅ ) ₂ CH ₃ , H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OCH ₃ ) ₃ ,

H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OC ₂ H ₅ ) ₃ , H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OCH ₃ ) ₂ CH ₃ ,

H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OC ₂ H ₅ ) ₂ CH ₃ , H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OH) ₃ ,

H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OH) ₂ CH ₃ , H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OCH ₃ ) ₃ , H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OC ₂ H ₅ ) ₃ , cycloC ₆ Hn H (CH ₂ ) ₃ -Si (OCH ₃ ) ₃ , cyclo-C ₆ Hn H (CH ₂ ) ₃ -Si (OC ₂ H ₅ ) ₃ , cyclo-C ₆ HnNH (CH ₂ ) ₃ -Si (OCH ₃ ) ₂ CH ₃ , cyclo-C ₆ HnNH (CH ₂ ) _3- Si (OC ₂ H ₅ ) ₂ CH ₃ , cyclo-C ₆ HnNH (CH ₂ ) ₃ -Si (OH) ₃ , cyclo-C ₆ Hn H (CH ₂ ) ₃ -Si (OH) ₂ CH ₃ , Phenyl-NH (CH ₂ ) ₃ -Si (OCH ₃ ) ₃ , phenyl-NH (CH ₂ ) ₃ -Si (OC ₂ H ₅ ) _3f phenyl-NH (CH ₂ ) 3-Si (OCH ₃ ) ₂ CH ₃ .

Phenyl-NH (CH ₂ ) 3-Si (OC ₂ H ₅ ) ₂ CH ₃ , phenyl-NH (CH ₂ ) ₃ -Si (OH) ₃ , phenyl-NH (CH ₂ ) 3-Si (OH) ₂ CH ₃ , HN ((CH ₂ ) ₃ -Si (OCH ₃ ) ₃ ) ₂ ,

HN ((CH ₂ ) ₃ -Si (OC ₂ H ₅ ) ₃ ) ₂ HN ((CH ₂ ) ₃ -Si (OCH ₃ ) ₂ CH ₃ ) ₂ ,

HN ((CH ₂ ) 3 -Si (OC ₂ H ₅ ) ₂ CH ₃ ) ₂ , cyclo-C ₆ HuNH (CH ₂ ) -Si (OCH ₃ ) ₃ , cycloC _s H ₁₁ NH (CH ₂ ) - Si (OC ₂ H ₅ ) ₃ , cyclo-C ₆ HnNH (CH ₂ ) -Si (OCH ₃ ) ₂ CH ₃ , cycloC _s HnNH (CH ₂ ) -Si (OC ₂ H ₅ ) ₂ CH ₃ , cyclo -C _e H _xl NH (CH ₂ ) -Si (OH) ₃ , cycloC ₆ HnNH (CH ₂ ) -Si (OH) ₂ CH ₃ , phenyl-NH (CH ₂ ) -Si (OCH ₃ ) ₃ ,

Phenyl-NH (CH ₂ ) -Si (OC ₂ H ₅ ) ₃ , phenyl-NH (CH ₂ ) -Si (OCH ₃ ) ₂ CH ₃ , phenyl-NH (CH ₂ ) -Si (OC ₂ H ₅ ) ₂ CH ₃ , phenyl-NH (CH ₂ ) -Si (OH) ₃ and

Phenyl-NH (CH ₂ ) -Si (OH) ₂ CH ₃ and their partial hydrolysates, wherein H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OCH ₃ ) 3, H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) 3-Si (OC ₂ H ₅ ) 3,

H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) 3 -Si (OCH ₃ ) ₂ CH ₃ , eyelo-C ₆ HnNH (CH ₂ ) ₃ -Si (OCH ₃ ) 3, cyclo-C ₃ HnNH (CH ₂ ) ₃ -Si (OC ₂ H ₅ ) ₃ and cyclo-C ₃ HnNH (CH ₂ ) ₃ -Si (OCH ₃ ) ₂ CH ₃ and in each case their partial hydrolysates are preferred and EP2013 / 050677

29

H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OCH ₃ ) ₃ , H ₂ N (CH ₂ ) ₂ NH (CH ₂ ) ₃ -Si (OCH ₃ ) ₂ CH ₃ , cycloC ₅ HnNH (CH ₂ ) 3-Si (OCH ₃ ) 3, cyclo-CgHuNH (CH ₂ ) ₃ -Si (OCH ₃ ) ₂ CH ₃ and in each case their partial hydrolysates are particularly preferred. The optionally used organosilicon compounds (D) can also assume the function of a curing catalyst or cocatalyst in the compositions according to the invention.

Furthermore, the organosilicon compounds (D) which may optionally be used according to the invention may act as adhesion promoters and / or as reactive diluents.

The organosilicon compounds (D) which may optionally be used according to the invention are commercially available products or can be prepared by processes customary in chemistry.

If the compositions according to the invention contain component (D), these are amounts of preferably 0.1 to 25 parts by weight, more preferably 0.5 to 10 parts by weight, in each case based on 100 parts by weight of component (A). The compositions of the invention preferably contain component (D).

The catalysts (E) optionally used in the compositions according to the invention may be any, hitherto known catalysts for compositions which cure by silane condensation.

Examples of metal-containing curing catalysts (E) are organic titanium and organic compounds, for example titanium acid esters, such as tetrabutyl titanate, tetrapropyl titanate, tetraisopropyl titanate and titanium tetraacetylacetonate. Tin compounds, such as dibutyltin dilaurate, dibutyltin maleate, dibutyltin di 50677

30 acetate, dibutyltin dioctanoate, dibutyltin acetylacetonate, di-butyltin oxides, and corresponding dioctyltin compounds.

Examples of metal-free curing catalysts (E) are basic compounds, such as triethylamine, tributylamine, 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [.3.0] ηοη-5-ene, 1 , 8-diazabicyclo [5.4.0] undec-7-ene, N, -bis (N, N-dimethyl-2-aminoethyl) -methylamine, N, N-dimethylcyclohexylamine, N, N-dimethylphenylamine and N- Ethylmorpholinine. Also guanidines such as e.g. 1,1,3,3-tetramethylguanidine or phosphazenes can be used as catalysts. Corresponding catalysts for silane crosslinking systems are i.a. in EP 1 563 822 A.

Likewise, as catalyst (E) it is possible to use acidic compounds, such as phosphoric acid and its esters, toluenesulfonic acid, sulfuric acid, nitric acid or else organic carboxylic acids, e.g. Acetic acid and benzoic acid.

If the compositions according to the invention comprise catalysts (E), these are amounts of preferably 0.01 to 20 parts by weight, more preferably 0.05 to 5 parts by weight, in each case based on 100 parts by weight of component (A).

In the case of the compositions according to the invention, it is then possible to dispense with metal-containing catalysts (E), in particular catalysts containing tin, if component (A) is wholly or at least partially, ie at least 10% by weight, preferably at least 20% Wt .-%, consists of compounds of formula (I), in which b is 1 and R ^{1 has} the meaning of hydrogen atom. This embodiment of the invention without metal and in particular without tin-containing catalysts is particularly preferred. 13 050677

As Organosiliciuraverbindung without basic nitrogen (F), in principle, all low molecular weight silanes can be used which have reactive alkoxysilyl groups, through which they can be incorporated during the curing of the foam with in the resulting three-dimensional network. These can perform various tasks, eg they can serve as reactive diluents, crosslinkers or as adhesion promoters. As component (F) it is possible to use epoxysilanes, such as glycidoxypropyltrimethoxysilanes, glycidoxypropylmethyldimethoxysilane, glycidoxypropyltriethoxysilane or glycidoxypropylmetyldiethoxysilane, 2- (3-triethoxysilylpropyl) maleic anhydride, N- (3-trimethoxysilylpropyl) urea, N- ( 3-triethoxysilylpropyl) urea, N- (trimethoxysilylmethyl) urea, N- (methyldimethoxysilymethyl) urea, N- (3-triethoxysilylmethyl) urea, N- (3-methyldiethoxysilylmethyl) urea, O-methylcarbamatomethyl methyldimethoxysilane, O-methylcarbamatomethyl-1-trimethoxysilane, O-ethylcarbamatomethylmethyldiethoxysilane, 0-ethylcarbamatomethyltriethoxysilane, O-methylcarbamatopropyltrimethoxysilane, O-ethylcarbamatopropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, methacryloxymethyltrimethoxysilane, methacryloxymethylmethyldimethoxysilane, MeOH thacryloxymethyltriethoxysilane, methacryloxymethylmethyldiethoxysilane, 3-acryloxypropyltrimethoxysilane, acryloxy methyltrimethoxysilane, acryloxymethylmethyldimethoxysilanes, acryloxymethyltriethoxysilane and acryloxymethylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methylmethyldimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenylmethyldimethoxysilane, and / or their partial condensates. Preference is given here on the one hand to inexpensive silanes, such as vinyl, methyl or phenyltrimethoxysilane, and their partial hydrolysates and, on the other hand, silanes having a polar group, for example the abovementioned O-alkylcarbamatoalkylsilanes, in particular O-methylcarbamatopropyltrimethoxysilane, and

Partial hydrolysates which have a particularly good compatibility with component (A). One or more silanes (F) can be used. If the inventive compositions contain silanes (F), they are amounts of preferably 0.5 to 30 parts by weight, more preferably 1 to 20 parts by weight, based in each case on 100 parts by weight of component (A ). As flame retardant (G), all flame retardants can be used, as they are used in conventional polyurethane foams, such as. Tris- (chloropropyl) -phosphate, dimethylpropylphosphonate, triethyl phosphate, cresyl phosphate, diphenyl cresyl phosphate, chlorinated paraffins and any other halogen- and / or phosphorus-containing compounds. Expanded graphite also represents a highly effective flame retardant.

If the compositions according to the invention contain flame retardants (G), these are amounts of preferably 1 to 100 parts by weight, more preferably 5 to 60 parts by weight, in each case based on 100 parts by weight of component (A).

If the compositions according to the invention contain flame retardants (F), these are amounts of preferably 1 to 100 parts by weight, more preferably 5 to 50 parts by weight, in each case based on 100 parts by weight of component (A).

The isocyanate-free, foamable mixtures may further contain the usual additives (H), such as, for example, foam stabilizers. gates and cell regulators, thixotropic agents, plasticizers, dyes or solvents.

The foam stabilizers and cell regulants which can be used are in particular the commercially available silicone oligomers modified by polyether side chains. Foam stabilizers are preferably added to the compositions according to the invention.

Examples of organic solvents are the compounds already mentioned above as solvents, preferably alcohols. However, preferably no organic solvents are added to the compositions according to the invention.

If the compositions of the invention comprise additives (H), they are amounts of preferably 0.01 to 30 parts by weight, more preferably 0.1 to 10 parts by weight, in each case based on 100 parts by weight of component (A).

The compositions of the invention are preferably those containing

(A) 100 parts by weight of compounds of the formula (I)

(B) 20 to 300 parts by weight of silicone resins containing units of the formula (II),

(C) 10 to 100 parts by weight of blowing agent,

possibly

(D) basic nitrogen-containing organosilicon compounds,

possibly

(E) catalysts,

possibly

(F) organosilicon compounds without basic nitrogen, optionally

(G) fire retardants, possibly

(H) additives.

In addition to components (A) to (H), the compositions according to the invention preferably contain less than 10 parts by weight of further constituents. Particularly preferably, the compositions according to the invention contain no further constituents.

The components used according to the invention may each be one type of such a component as well as a mixture of at least two types of a respective component.

A further subject of the invention are pressurized cans containing the foamable and crosslinkable compositions according to the invention.

Another object of the invention is the use of the foamable and crosslinkable compositions according to the invention as einkompo- nent sprayable mounting foams in particular for filling joints or cavities.

Another object of the invention is the use of the foamable and crosslinkable compositions according to the invention as a component in two-component sprayable mounting foams, in particular for filling joints or cavities.

A further subject of the invention is a cured foam body produced from the foamable and crosslinkable compositions according to the invention, e.g. a foamed joint or a foamed cavity.

In the examples described below, all viscosity data refer to a temperature of 25 ° C. Unless Otherwise stated, the examples below are at a pressure of the surrounding atmosphere, ie at about 1000 hPa, and at room temperature, ie at about 23 ° C, or at a temperature, the mixing of the reactants at room temperature without additional heating or cooling, and performed at a relative humidity of about 50%. Furthermore, all parts and percentages are by weight unless otherwise specified.

Example 1 :

In a 500 ml reaction vessel with stirring, cooling and heating possibilities, 73.2 g (42.17 mmol) of an 80:20 mixture of toluene-2,4-diisocyanate and toluene-2,6-diisocyanate (TDI) are added. initially charged with 0.06 g of butyl phosphate and heated to about 50 ° C. Then a mixture of 83.2 g (195.8 mmol) of a polypropylene glycol having an average molecular weight M _n of 425 g / mol and 13.8 g (56.9 mmol) of 1-hexadecanol is added. The temperature of the reaction mixture should not rise above 80 ° C. The polypropylene glycol had previously been dewatered by heating at 100 C for 1 h in an oil pump vacuum. After the addition is stirred for 15 min at 80 ° C.

It is then cooled to about 50 ° C and are 5 g of vinyltrimethoxysilane (GENIOSIL XL 10 from. Wacker-Chemie AG, D-Munich) added as a reactive diluent. Thereafter, 0.28 g

Jeffcat DMDLS (Huntsman, Texas USA-Woodlands) is added dropwise 160.0 g, 378.6 mmol) Z \ 7-phenylaminomethyl-methyldimethoxysilane (GENIOSIL XL 972 from Wacker-Chemie AG, D-Munich) and stirred then for 60 min at 80 ° C. In the resulting prepolymer mixture, no more isocyanate groups can be detected by IR spectroscopy. A clear, transparent prepolymer mixture is obtained which at 50 ° C. has a viscosity of 17.8 Pas. It is easy to pour and process.

Example 2:

40 g of the prepolymer mixture from Example 1 and 10 g of a solvent-free, liquid phenyl silicone resin, which is composed exclusively of phenyl-functional T units, a content of methoxy groups of 10-30 wt .-% and an average molecular weight of 1500-2500 daltons has (commercially available under the name SILRES ^* "IC 678 from Wacker Chemie AG, D-Munich), are filled into a pressure glass valve and with 1.2 g foam stabilizer Tegostab 8443 (Evonik, D-Essen) and 1.5 g JV- (2-aminoethyl) -3-aminopropyltrimethoxysilane (GENIOSIL GF 91, from Wacker-Chemie AG, D-Munich).

Subsequently, this mixture is treated with a propellant mixture of 18 ml of a propane / butane mixture (2: 1) and 1.5 ml of dimethyl ether as blowing agent. A vigorous shaking then gives a thin-bodied emulsion which is stable for several hours.

When standing for several days, it comes to a segregation, with 8-10 ml physically no longer dissolved propellant settle as the upper phase. The lower phase, which becomes completely clear on prolonged standing, contains prepolymer, silicone resin and additives as well as the remaining propellant.

However, both phases are so fluid that they can be easily emulsified by re-shaking briefly again. The emulsion is again stable for several hours before the propellant phase begins to settle again slowly at the top. When applying the well-emulsified mixture by shaking a stable, white foam is obtained, which is tack-free after about 15 minutes. The time until complete curing is about 6 h. The hardened foam is characterized by a very high hardness and has a very good pore structure.

Claims

claims

Containing foaming and crosslinkable compositions

(A) 100 parts by weight of compounds (A) of the formula

Y- [(CR ¹ ₂ ) _b -SiR _a ⁽ OR ² ) ₃ -a] x (I) where

denotes an x-valent polymer radical bound via nitrogen, oxygen, sulfur or carbon,

may be the same or different and represents a monovalent, optionally substituted, Sic-bonded hydrocarbon radical,

may be identical or different and represents hydrogen atom or a monovalent, optionally substituted hydrocarbon radical which may be attached to the carbon atom via nitrogen, phosphorus, oxygen, sulfur or carbonyl group,

may be the same or different and represents hydrogen atom or a monovalent, optionally substituted hydrocarbon radical,

is an integer from 1 to 10,

may be the same or different and is 0, 1 or 2 and may be the same or different and is an integer from 1 to 10,

) more than 1 part by weight of silicone resins containing units of the formula

R ³ _C (R ⁴ O) _d R ⁵ _e SiO (4- _c -de) / 2 (II) where R ^{3 may be} identical or different and is hydrogen, a monovalent, SiC-bonded, optionally substituted aliphatic hydrocarbon radical or a divalent, optionally substituted, aliphatic hydrocarbon radical bridging two units of the formula (II),

R ^{4 may be the} same or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical,

R ^{5 may be the} same or different and is a monovalent,

SiC-bonded, optionally substituted aromatic hydrocarbon radical,

c is 0, 1, 2 or 3,

d is 0, 1, 2 or 3, and

e is 0, 1 or 2, preferably 0 or 1, with the proviso that the sum of c + d + e is less than or equal to 3 and in at least 40% of the units of formula (II) the sum c + e is equal 0 or 1 is, and

C) more than 1 part by weight of a propellant gaseous at 20 ° C and 1000 hPa.

2. Foaming and crosslinkable compositions according to claim 1, in which the polymer radical Y contains organic polymer radicals whose polymer chain is selected from polyesters, polyurethanes, polyoxyalkylenes, hydrocarbon polymers, polyamides, polyacrylates, polymethacrylates, polycarbonates and mixtures thereof.

3. Foaming and crosslinkable compositions according to claim 1 or 2, wherein the end groups of the compounds (A) are selected from the general formulas

-C (= O) -NH- (CR b-SiRaiOR ² ) (HD and

-NH-C (= O) -NR '- (CR ¹ ₂ ) _b -SiR _a (OR ² ) ₃ -a (IV), wherein the radicals and indices have one of the meanings given in claim 1.

4. foaming and crosslinkable compositions according to claim 1 to 3, in which the silicone resins (B) have a mean molecular weight (number average) M _n of 400 g / mol to 400 000 g / mol.

5. Foaming and crosslinkable compositions according to claim 1 to 4, wherein the blowing agent is selected from hydrocarbons having 1-4 carbon atoms, fluorocarbons having 1-4 carbon atoms and dimethyl ether and mixtures thereof.

6. Foaming and crosslinkable compositions according to claim 1 to 5, which contain

(A) 100 parts by weight of compounds of the formula (I)

(B) 20 to 300 parts by weight of silicone resins containing units of the formula (II), and

(C) 10 to 100 parts by weight of blowing agent.

7. Pressure cell containing the foamable and crosslinkable compositions according to claims 1 to 6.

8. Use of the foamable and crosslinkable compositions according to claim 1 to 6 as one-component sprayable mounting foams.

9. Use of the foamable and crosslinkable compositions according to claim 1 to 6 as a component in two-component sprayable mounting foams.

10. Hardened foam body, prepared from the foamable and crosslinkable compositions according to claim 1 to 6.