DE102008034272A1 - Isocyanate-free foamable mixture, useful e.g. for filling cavities, comprises alkoxysilane terminated prepolymers obtained from di- or polyisocyanates, polyols and amino-functionalized alkoxysilanes; liquid flame retardant; and propellant - Google Patents

Abstract

Isocyanate-free foamable mixture (I) comprises: alkoxysilane terminated prepolymers obtained from di- or polyisocyanates, polyols and hydroxy- or amino-functionalized alkoxysilanes or polyols and isocyanato functionalized alkoxysilanes or mixture of prepolymers of diisocyanates or polyisocyanates, polyols and hydroxy- or amino-functionalized alkoxysilanes or polyols and isocyanato functionalized alkoxysilanes; liquid flame retardant; and propellant, where the prepolymer or its mixture, flame retardant and/or propellant at 23[deg] C, exhibit a viscosity of 100-25000 (preferably 500-10000) mPas. An independent claim is included for the preparation of (I) comprising producing prepolymer in disposable pressurized containers (aerosol cans), and optionally mixing with propellant and/or flame retardants.

Description

The Invention relates to isocyanate-free foamable mixtures, which can be further processed to foam plastics.

Foamed plastics in the context of this invention are produced from disposable pressure vessels at the place of their use, one therefore speaks of a local foam ( DIN 18159 ), in particular, these are moisture-curing one-component systems. The composition to be foamed is usually in disposable pressure containers (aerosol cans). These sprayable foams are used primarily in construction for sealing, dams and mounting, z. As of joints, roofs, windows and doors or to fill cavities, especially in the construction sector. As excellent insulating materials, they lead to a good thermal insulation of the foamed structures. Other applications include the insulation of pipelines or the foaming of cavities in technical equipment and machinery.

at the hitherto mainly used mounting foams these are polyurethane foams (PU foams), in the uncrosslinked state consist of prepolymers, the over have a high concentration of free isocyanate groups. These isocyanate groups are capable of reacting with suitable reactants to enter at room temperature addition reactions, which hardened spray foam after application becomes. The foam structure is characterized by the Einmengen a volatile Propellant in the still uncrosslinked raw material and / or by Carbon dioxide produced, the latter by a reaction of the Isocyanate is formed with water. The spreading of the foam usually happens from disposable pressure vessels (pressure cans or aerosol cans) by the autogenous pressure of the propellant.

When Reactants for the isocyanates are alcohols with two or more OH groups - especially branched and unbranched Polyols - or water. The latter reacts with the isocyanates under the already mentioned release of carbon dioxide to primary amines, which then go directly to another, can still add unused isocyanate group. It arise urethane or urea units, due to their high polarity and their ability to train of hydrogen bonds in the cured material can form semi-crystalline substructures and so on Foams with high hardness, pressure and tear resistance to lead.

Next The carbon dioxide are used as blowing agents usually gases that already condensable at relatively low pressure and thus admixed the prepolymer mixture in the liquid state Can be without the spray cans excessively high pressures must be suspended.

PU spray foams are both as so-called one-component (1K) and as produced two-component (2K) foams. The 1K foams harden only through the contact the isocyanate-containing prepolymer mixture with the humidity out. By the 1K foams during the curing reaction released carbon dioxide can also support the formation of foam become. 2K foams contain an isocyanate and a polyol component, which mix well with each other just before foaming and by the reaction of the polyol with the Cure isocyanates. Advantage of the 2K systems is one extremely short curing time of z. T. only a few minutes until fully cured. You own however, the disadvantage that it has a more elaborate design Pressure cell with two chambers need and also in the handling significantly less comfortable than the 1K systems.

The Hardened PU foams are characterized above all through their excellent mechanical and thermal insulation Properties, and they have a very good Liability to many substrates found in the construction industry and are under dry and UV protected conditions of almost unlimited durability. Other advantages lie in the toxicological safety of the cured Foams from the moment all isocyanate groups, especially those of the monomeric isocyanates, quantitatively reacted You are curing in a very short time and are easy manageable. Due to these properties, PU foams have very well proven in practice.

In addition to relatively high molecular weight prepolymers, the prepolymer mixtures based on polyisocyanates and polyols used in pressure cans for foam generation usually also contain polyisocyanate which has not reacted or only reacted to low molecular weight prepolymers. These constituents of the prepolymer mixtures, because of their higher volatility, the real hazard and are therefore undesirable because the isocyanates, especially the monomeric isocyanates due to their high reactivity and Their high vapor pressure can also produce extremely irritating and toxic effects.

The uncrosslinked spray foams are up to complete Curing thus not toxicologically harmless. Critical is here in addition to the direct contact of the prepolymer mixture with the Skin especially a possible aerosol formation during the application of the foam or the evaporation of low molecular weight Ingredients, eg. B. of monomeric isocyanates. This exists the danger that toxicologically harmful compounds over the breathing air is absorbed. In addition, isocyanates have a significant allergenic and sensitizing potential and can u. a. Trigger asthma attacks. To be aggravated These risks still by the fact that the PU spray foams Often not by trained and experienced users but used by hobbyists and DIYers, allowing proper handling can not always be assumed.

Also are the amines resulting from a reaction of monomeric diisocyanates can form with an excess of water, in many cases suspected of being carcinogenic.

Next this potential hazard, which, if appropriate Handling rather than low, but there are many Users an acceptance problem, by the declaration obligation of such products as toxic and the classification of the emptied or partially emptied containers as hazardous waste, which in some Countries such as B. Germany even by means of a costly Recycling system made available for recycling has to be, is still being promoted.

To overcome these disadvantages, inter alia, in WO 96/06124 already described prepolymers for spray foams containing no or only very low concentrations of monomeric isocyanates. A disadvantage of such systems, however, is the fact that the prepolymers thus prepared still have reactive isocyanate groups, so that such PU spray foams are from a toxicological point of view, although cheaper than conventional foams, but not as safe to call. Also, the acceptance and waste problems are not solved completely satisfactory by such foam systems.

WO 2000/04069 describes prepolymer blends for the production of sealing and insulating foams which contains a prepolymer component, a propellant gas component and customary foaming additives. The prepolymer component is intended to be a silane-terminated polyurethane prepolymer which has at least two Si (OR) _x (R) _3-x groups in the molecule, where R is in each case an alkyl radical having 1 to 6 carbon atoms and x is an integer of 1 to 3 is. Such prepolymer components often have a very high viscosity of over 1 000 000 mPa · s and lead to considerable problems in canned foam production, which is why they often have to be filled at high temperatures. The intermiscibility of the viscous prepolymers with the other ingredients is also unsatisfactory. Such foamable mixtures are thus difficult to handle in the production and filling process in the pressure cans.

verfügen sollen. in der Formel stellt X und Y ein Sauerstoffatom, eine N-R³-Gruppe oder ein Schwefelatom dar, R¹ ist ein Alkyl-, Alkenyl- oder Arylrest mit 1-10 Kohlenstoffatomen, R² ein Alkylrest mit 1-2 Kohlenstoffatomen oder einen – Oxaalkyl-alkylrest mit insgesamt 2-10 Kohlenstoffatomen, R³ ein Wasserstoffatom, einen Alkyl-, Cycloalkyl-, Alkenyl- oder Arylrest mit 1-10 Kohlenstoffatomen oder eine -CH₂-SiR¹ _m(OR²)_3-m-Gruppe und, z kann die Werte 0 oder 1 bedeuten, dabei soll mindestens eine der beiden Gruppen X oder Y eine NH-Funktion sein. Diese Prepolymeren weisen ebenfalls bei Raumtemperatur eine sehr hohe Viskosität auf. WO 2002/066532 discloses isocyanate-free foamable mixtures containing isocyanate-free, alkoxysilane-terminated prepolymers and blowing agents, wherein the prepolymers via silane derivatives of the general formula

should have. in the formula, X and Y represent an oxygen atom, an NR ³ group or a sulfur atom, R ¹ is an alkyl, alkenyl or aryl group having 1-10 carbon atoms, R ^{2 means} an alkyl group having 1-2 carbon atoms or an - oxaalkyl R ^{3 is} a hydrogen atom, an alkyl, cycloalkyl, alkenyl or aryl radical having 1-10 carbon atoms or a -CH ₂ -SiR ¹ _m (OR ² ) _3-m group and z can mean 0 or 1, and at least one of the two groups X or Y should be an NH function. These prepolymers also have a very high viscosity at room temperature.

The WO 2005/049684 relates to silyl groups and NCO-bearing polyurethanes or polyureas which can be prepared using asymmetric diisocyanates and substituted alkoxyaminosilanes. There are further described preparations, and their use as surface coating, adhesives, mounting foams, potting compounds and soft, hard and integral foams. These prepolymers are also described as having medium viscosity to high viscosity.

WO 96/38453 describes moisture-curing alkoxysilane functional polyurethanes prepared from a hydroxy-functional alkoxysilane, in particular a Hydroxyalkylencarbamoylalkylen-alkoxysilane, and an isocyanate-functional polyurethane prepolymer. According to the teaching of this document, the alkoxysilane-functional polyurethanes can be used for application in moisture-curing adhesives, sealants and similar preparations. Foamable compositions are not described.

In a similar manner as the previously cited Scripture discloses US-A-5866651 moisture-curing sealant compositions based on polyetherurethanes prepared from Hydroxyalkylencarbamoylalkylen-alkoxysilanes. According to the teaching of this document, the polyether segments should have more than 15 mol% and less than 40 mol% ethylene oxide units, wherein the polyether segments should have a number average molecular weight between 2000 and 8000, wherein the ethylene oxide units are preferably arranged at the ends of the propylene oxide. Foamable compositions are also not described in this document.

task The present invention is therefore isocyanate-free foamable To provide compositions having a low viscosity exhibit it during manufacture and packaging in Disposable pressure vessels (pressurized cans or aerosol cans) easily to handle.

The achievement of the object of the invention can be found in the claims. It consists essentially in the provision of isocyanate-free, foamable mixtures containing
alkoxysilane-terminated prepolymers preparable from di- or polyisocyanates, polyols and hydroxy- or amino-functional alkoxysilanes or from polyols and isocyanato-functional alkoxysilanes or
Mixtures of prepolymers of di- or polyisocyanates, polyols and hydroxy- or amino-functional alkoxysilanes or of polyols and isocyanato-functional alkoxysilanes with liquid flame retardants and blowing agents.

there has the prepolymer or the mixture of prepolymer, flame retardant and / or blowing agent at 23 ° C a dynamic viscosity from 100 to 25,000 mPa · s, preferably 500 to 10,000 mPa · s on.

Canned foam formulations contain propellants, which is a determination of viscosity not readily admit. To simulate them nevertheless is the skilled person known that a substitution of the propellant gases with methylal and pentane lead to a non-pressurized foam formulation. According to the invention for this purpose the propellant gases of Foam formulation by a mixture of 8.4% methylal and Substituted 12.6% pentane, thereby revealing the rheological Ratios of a DME / propane / butane formulated foam composition. It is observed that mixtures below 25,000 mPa · s still moderate, below 10 000 especially good can be applied. Another advantage is the type of viscosity. A pseudoplastic mixture shows a low when applied Viscosity and after order a high, the construction of the foam is stabilized during curing.

The Measurement takes place with a deformation-controlled rotation rheometer from TA Instruments. As measuring systems are cone-plate systems with a taper angle of 0.5 ° to 3 ° and plate-plate systems used with a gap between 200 mm-800 mm. The Viscosity values are accompanied by a rotation test RT determined. After a rest period of 10 s, the shear deformation becomes from 0 s-1 to 100 s-1 in a time of 20 s in achieved linear steps.

One Another object of the present invention is a method for the preparation of the aforementioned isocyanate-free foamable Mixtures in which the preparation of the prepolymer in a disposable pressure vessels (Aerosol cans), if necessary in admixture with blowing agents and / or flame retardants he follows.

worin m 0, 1 oder 2 ist, R¹ ein Alkylrest mit 1 bis 4 Kohlenstoffatomen, R² ein Alkylrest mit 1 bis 4 Kohlenstoffatomen, R³ ein divalenter organischer Rest mit 1 bis 10 Atomen ausgewählt aus C, N, S und/oder O in der Kette ist, R⁴ ein Wasserstoffatom oder ein Alkylrest mit 1 bis 10 Kohlenstoffatomen ist und R eine difunktionelle organische Gruppe ist.In a preferred embodiment of the foamable mixtures, the alkoxysilane-terminated prepolymer (A) is prepared from di- or polyisocyanates, polyols and compounds having the general formula (1)

wherein m is 0, 1 or 2, R ^{1 is} an alkyl radical having 1 to 4 carbon atoms, R ^{2 is} an alkyl radical having 1 to 4 carbon atoms, R ^{3 is} a divalent organic radical having 1 to 10 atoms selected from C, N, S and / or O in the chain, R ^{4 is} a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R is a difunctional organic group.

alternative the alkoxysilane-terminated prepolymer is prepared from or polyisocyanates, polyols and amino-functional alkoxysilanes.

wobei n eine ganze Zahl zwischen 1 und 6 ist,
Q ist N, O, S, eine kovalente Bindung oder -NR⁴ und
R⁴ und R⁵ können unabhängig voneinander ein Wasserstoffatom oder ein Alkylrest mit 1 bis 10 Kohlenstoffatomen sein.In a further embodiment, R ³ in formula (1) has the following structural elements (2):

where n is an integer between 1 and 6,
Q is N, O, S, a covalent bond or -NR ⁴ and
R ⁴ and R ⁵ may independently be a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

worin m 0, 1 oder 2 ist, R¹ ein Alkylrest mit 1 bis 4 Kohlenstoffatomen, R² ein Alkylrest mit 1 bis 4 Kohlenstoffatomen, R⁴ ein Wasserstoffatom oder ein Alkylrest mit 1 bis 10 Kohlenstoffatomen und R⁶ ein zwei- oder dreiwertiger Rest eines Prepolymers auf Basis von Polyoxyalkylenglycolen.In a further embodiment according to the invention, the alkoxysilane-terminated prepolymer can be represented by the general formula (3)

wherein m is 0, 1 or 2, R ^{1 is} an alkyl radical having 1 to 4 carbon atoms, R ^{2 is} an alkyl radical having 1 to 4 carbon atoms, R ^{4 is} a hydrogen atom or an alkyl radical having 1 to 10 carbon atoms and R ^{6 is} a di- or trivalent radical a prepolymer based on polyoxyalkylene glycols.

In In the formulas (1) and (3), R can be a difunctional straight or branched alkyl radical having 2 to 6 carbon atoms and m can be zero or one.

In a variant is first made of one or more polyols and di- or polyisocyanates an NCO-terminated prepolymer prepared, that in a subsequent step with one or more hydroxy or amino-functional alkoxysilanes to an isocyanate-free, alkoxysilane-terminated prepolymer is reacted.

In Another variant is initially an isocyanate-functional Alkoxysilane of a low molecular weight hydroxy or amino functional Alkoxysilane and a diisocyanate synthesized in stoichiometric excess, wherein the NCO / OH ratio is 1.5 to 3, preferably 2. In a subsequent reaction, the thus prepared isocyanate-functional Alkoxysilane with a polyol or a polyol mixture to a isocyanate-free, alkoxysilane-terminated prepolymer or a prepolymer mixture implemented.

The hydroxy-functional alkoxysilane is preferably by reaction an aminosilane with primary or secondary Amino groups with a carbonate selected from ethylene carbonate, Propylene carbonate, butylene carbonate, carbonates prepared from 1,3-propanediol, 3,5-hexanediol, 3,5-heptanediol, 3,5-nonananediol, or a lactone, selected from propiolactone, butyrolactone or caprolactone produced. Alternatively, the hydroxy-functional alkoxysilane a reaction product of a Michael addition of a hydroxyalkyl (meth) acrylate be with an aminosilane.

The aminosilane can be selected from 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane (for example Dynasilan AMMO, Evonik or Geniosil GF 96, from Wacker), N- (n-butyl) -3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane , 3-aminopropylmethyldiethoxysilane, N-cyclohexy laminomethylmethyldiethoxysilane, N-cyclohexylaminomethyltriethoxysilane, N-phenylaminomethyltrimethoxysilane (eg Geniosil XL 973, from Wacker), N-cyclohexyl-3-aminopropyltrimethoxysilane, 1-anilinomethyldimethoxymethylsilane (for example Geniosil XL 972, from Wacker), N- Phenyl-3-aminopropyltrimethoxysilane (eg Y-9669 from the company Momentive) or bis (3-triethoxysilylpropyl) amine (Silquest A-1170, from GE).

Hydroxyalkyl (meth) acrylates may in principle be monoesters of acrylic acid or methacrylic acid with C ₂ to C ₂₀ diols, particular preference is given to hydroxyethyl acrylate, hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate or 2-hydroxybutyl acrylate, 2 Hydroxybutyl methacrylate, 3-hydroxybutyl acrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, or 6-hydroxyhexyl acrylate, 6-hydroxyhexyl methacrylate.

As diisocyanates can be used:
Ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,4-tetramethoxybutane diisocyanate, 1,6-hexamethylene diisocyanate (HDI), cyclobutane-1,3-diisocyanate, cyclohexane-1,3- and 1,4-diisocyanate, bis (2-isocyanato ethyl) fumarate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 2,4- and 2,6-hexahydrotoluylene diisocyanate, hexahydro-1,3- or -1,4-phenylene diisocyanate , Benzidine diisocyanate, naphthalene-1,5-diisocyanate, 1,6-diisocyanato-2,2,4-trimethylhexane, 1,6-diisocyanato-2,4,4-trimethylhexane, xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI) , 1,3- and 1,4-phenylene diisocyanate, 2,4- or 2,6-toluene diisocyanate (TDI) or mixtures of isomers of TDI, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate or 4,4'-diphenylmethane diisocyanate (MDI) and their isomer mixtures. Also suitable are partially or fully hydrogenated cycloalkyl derivatives of MDI, for example fully hydrogenated MDI (H12-MDI), alkyl-substituted diphenylmethane diisocyanates, for example mono-, di-, tri- or tetraalkyldiphenylmethane diisocyanate and their partially or fully hydrogenated cycloalkyl derivatives, 4,4'-diisocyanatophenylperfluoroethane, phthalic acid bis-isocyanatoethyl ester, 1-chloromethylphenyl 2,4- or 2,6-diisocyanate, 1-bromomethylphenyl 2,4- or 2,6-diisocyanate, 3,3-bis-chloromethyl ether-4,4'- diphenyl diisocyanate, sulfur-containing diisocyanates, as obtainable by reacting 2 mol of diisocyanate with 1 mol of thiodiglycol or Dihydroxydihexylsulfid, the diisocyanates of Dimerfettsäuren, or mixtures of two or more of said diisocyanates, in question.

The isocyanatosilane thus prepared preferably has, measured at 23 ° C., a dynamic viscosity of 50 to 500,000 mPa · s, preferably 50 to 250,000 mPa · s DIN / EN / ISO 2555 on. Optionally, the measurement is carried out in admixture with flame retardants and / or blowing agents. In the presence of blowing agents, the viscosity can be measured even at low temperatures, ie below the boiling point of the blowing agent, and then extrapolated to 23 ° C. This is possible because these mixtures exhibit Newtonian flow behavior, allowing error-free extrapolation to other temperatures without problems.

Although in principle a large number of polymers carrying at least two hydroxyl groups can be used as polyol compounds, examples include polyester polyols, hydroxyl-containing polycaprolactones, hydroxyl-containing polybutadienes or polyisoprenes and their hydrogenation products or hydroxyl-containing polyacrylates or polymethacrylates. For reasons of viscosity (of the prepolymer), the molecular weight range of the polyols should not be higher than 4000. Polyols which are very particularly preferred are polyoxyalkylene glycols, in particular polyethylene oxides (PEG) and / or polypropylene oxides (PPG) having a molecular weight (M _n ) between 400 and 2000.

When Reactive thinner can be z. B. use the following substances: polyalkylene glycols reacted with isocyanatosilanes (eg Synalox 100-50B, DOW), carbamatopropyltrimethoxysilane, alkyltrimethoxysilane, Alkyltriethoxysilane such as methyltrimethoxysilane, methyltriethoxysilane and vinyltrimethoxysilane (VTMO, Geniosil XL 10, Wacker), vinyltriethoxysilane, Phenyltrimethoxysilane, phenyltriethoxysilane, octyltrimethoxysilane, Tetraethoxysilane, vinyldimethoxymethylsilane (XL12, Wacker), vinyltriethoxysilane (GF56, Wacker), vinyltriacetoxysilane (GF62, Wacker), isooctyltrimethoxysilane (10 trimethoxy), isooctyltriethoxysilane (10 triethoxy, Wacker), N-trimethoxysilylmethyl-O-methylcarbamate (XL63, Wacker), N-dimethoxy (methyl) silylmethyl-O-methyl-carbamate (XL65, Wacker), hexadecyltrimethoxysilane, 3-octanoylthio-1-propyltriethoxysilane and partial hydrolysates of these compounds. Particularly preferred Methyl, vinyl, and phenyltrimethoxysilane and / or their partial hydrolysates and mixtures thereof in concentrations of from 1% to 20% by weight, preferably between 1.5 and 5 wt .-%, based on the prepolymer.

As a propellant principle, a variety of volatile hydrocarbons can be used. Particularly preferred blowing agents are selected from hydrocarbons and fluorohydrocarbons each having 1-5 carbon atoms and dimethyl ether (DME) and mixtures thereof. The propellant who in amounts of from 5 to 40 wt .-%, preferably from 5 to 20 wt .-%, based on the total foamable mixture used.

The Flame retardant is selected from the group halogenated (In particular brominated) ethers of the type "Ixol" of Fa. Solvay, brominated alcohols, in particular Dibromneopentylakohol, Tribromoneopentyl alcohol and PHT-4-diol (1,2-benzenedicarboxylic acid, 3,4,5,6-tetrabromo-, 2- (2-hydroxyethoxy) ethyl-2-hydroxypropyl ester), organic phosphates, in particular diethyl ethane phosphonate (DEEP), triethyl phosphate (TEP), dimethyl propyl phosphonate (DMPP), Diphenyl cresyl phosphate (DPK), as well as chlorinated phosphates (eg TMCP, Fa. Albemarle), in particular tris (2-chloroethyl) phosphate, tris (2-chloroisopropyl) phosphate (TCPP), tris (1,3-dichloroisopropyl) phosphate, tris (2,3-dibromopropyl) phosphate and tetrakis (2-chloroethyl) ethylenediphosphate or mixtures thereof. Preferably, the mixture contains the flame retardant in an amount of from 1 to 65% by weight, more preferably from 10 to 65 wt .-%, in particular from 15 to 60 wt .-%, particularly preferably from 20 to 50% by weight, based on the total weight of the mixture. It may be advantageous, at least in part, from the aforementioned Flame retardants to select those containing hydroxyl groups as these are incorporated into the polymeric foam scaffold become.

It was already noted above that a particularly beneficial Inventive process the preparation of the Prepolymer in the retail container, the disposable pressure vessel (Aerosol can) can be done, if necessary, mixing with propellants and / or flame retardants useful. For this Approach is in particular the use of the aforementioned Isocyanatosilanes of diisocyanates and hydroxy- or amino-functional Alkoxysilanes.

When Catalysts can be used all known compounds be the hydrolytic cleavage of the hydrolyzable groups the silane groups and the subsequent condensation the Si-OH group to Siloxangruppierungen (crosslinking reaction or Adhesion Function) catalyze. Examples for this are titanates such as tetrabutyl titanate and tetrapropyl titanate, Tin carboxylates such as dibutyltin dilaurate (DBTL), dibutyltin diacetate, Dibutyltin diethylhexanoate, dibutyltin dioctoate, dibutyltin dimethyl maleate, Dibutyltin diethyl maleate, dibutyltin dibutyl maleate, dibutyltin diiosooctyl maleate, Dibutyltin ditridecyl maleate, dibutyltin dibenzyl maleate, dibutyltin maleate, Dibutyltin diacetate, tin octoate, dioctyltin disteareate, dioctyltin dilaurate, Dioctyltin diethyl maleate, dioctyltin diisooctylmaleate, dioctyltin diacetate, and tin naphthenoate; Tin alkoxides such as dibutyltin dimethoxide, dibutyltin diphenoxide, and dibutyltin diisoproxide; Tin oxides such as dibutyltin oxide, and dioctyltin oxide; Reaction products between dibutyltin oxides and phthalic acid esters, dibutyltinbisacetylacetonate; Organoaluminum compounds such as aluminum trisacetylacetonate, Aluminum trisethylacetoacetate, and diisopropoxyaluminum ethylacetoacetate; Chelate compounds such as zirconium tetraacetylacetonate, and titanium tetraacetylacetonate; lead octanoate; Amine compounds or their salts with carboxylic acids, such as butylamine, octylamine, laurylamine, dibutylamines, monoethanolamines, Diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, Oleylamines, cyclohexylamine, benzylamine, diethylaminopropylamine, Xylylenediamine, triethylenediamine, guanidine, diphenylguanidine, 2,4,6-tris (dimethylaminomethyl) phenol, Morpholine, N-methylmorpholine, 2-ethyl-4-methylimidazoles, and 1,8-diazabicyclo- (5,4,0) -undecene-7 (DBU), a low molecular weight polyamide resin obtained from an excess of a Polyamine and a polybasic acid, adducts of one Polyamine in excess with an epoxide, Silanhaftvermittler with Amino groups such as 3-aminopropyltrimethoxysilane, and N- (β-aminoethylaminopropylmethyldimethoxysilane particularly preferred catalysts are titanium (diisopropoxide) bis (acetylacetonate) (TAA), titanium (IV) oxide acetylacetonate, aluminum acetylacetonate, 1,4-diazabicyclo [2,2,2] octane, N, N-dimethylpiperazine, 1,8-diazabicyclo [5.4.0] undec-7-ene, dimorpholinodimethyl ether, Dimorpholinodiethyl ether (DMDEE) or mixtures thereof. The catalyst, preferably mixtures of several catalysts, are in an amount from 0.01 to about 5 wt .-% based on the total weight of the preparation used.

Farther can the foamable invention Mixtures contain other customary auxiliaries and additives, These include in particular foam stabilizers in quantity ranges between 0.1 and 5 wt .-%, based on the total mixture.

The foamable mixtures according to the invention harden after application from the aerosol can with the ambient humidity to fine-celled foams, so that from the foamable mixtures for sealing, dams and mounting, e.g. As of joints, roofs, windows and Doors or to fill cavities are suitable.

In the following embodiments, the invention be explained in more detail, with the selection of the For example, no limitation on the scope of the subject invention should represent.

Examples

Production of precursors and prepolymers:

Example 1:

In A stirred flask was 138 g of propylene carbonate and 220 g 3-aminopropyltrimethoxysilane (Dynasilan AMMO, Evonik) 12 hours stirred at room temperature. An examined in the IR spectrometer Sample showed complete conversion of the propylene carbonate and indicated the further processing.

Example 2:

In A stirred flask was charged with 144 g of hydroxypropyl methacrylate and slowly 211 g of 1-anilinomethyldimethoxymethylsilane (Geniosil XL972, from Wacker). It was stirred at room temperature. A sample examined in the IR spectrometer showed the complete Implementation of the Michael reaction product and indicated the further processing.

Example 3:

In a stirred flask 96 g of TDI-100 were submitted and within One hour 155 g of the reaction product of propylene carbonate with Aminosilane from Example 1 is added dropwise so that the temperature below remained at 40 ° C. The resulting polymer was cooled and mixed with 6 g of vinyltrimethoxysilane. The viscosity of the resulting isocyanatosilane was 25,000 mPa · s at room temperature (23 ° C).

Example 4:

In 70 g of MDI-50 and 25 g of TMCP were initially charged to a stirred flask. Subsequently, within one hour, 80 g of the reaction product of propylene carbonate with aminosilane from Example 1 is added dropwise so that the temperature remained below 40 ° C. The resulting Polymer was cooled and treated with 6 g of vinyltrimethoxysilane added. The viscosity of the resulting isocyanatosilane was 95,000 mPa · s at room temperature (23 ° C).

Example 5:

In a stirred flask, 417 g crude MDI (Desmodur 44 V20) and 160 g TMCP submitted. Subsequently, within 375 g of the reaction product of propylene carbonate with Aminosilane from Example 1 is added dropwise so that the temperature below of 50 ° C remained. The resulting polymer was cooled and mixed with 6 g of vinyltrimethoxysilane. The viscosity of the resulting isocyanatosilane was 325,000 mPa · s at room temperature (23 ° C).

Example 6:

130 g (20 mmol) of TDI-100 and 1.3 g of benzoyl chloride were charged and then 170 g (10 mmol) of PPG 400 are added dropwise. After reaching of the theoretical NCO value, the hydroxysilane slowly drained off Example 1 added. The resulting prepolymer has a Viscosity was 800 Pas at 23 ° C.

Example 7:

24.2 g of PPG 400 were mixed with 51.6 g of the addition product of Example 3 mixed and shaken, with a moderate heat of reaction originated. The resulting prepolymer has a viscosity from 900 pas at 23 ° C.

Example 8 (comparison):

199 g (10 mmol) of polypropylene glycol having a molecular weight (M _n ) of 400 g / mol was charged with 151 g (20 mmol) of TDI as diisocyanate and tin / bismuth catalysis (Borchikat 22/24) to NCO-terminated prepolymer at 80 ° C converted. The conversion is carried out under NCO control and as soon as the theoretical NCO value of the prepolymer has been reached (titrimetrically), 60 g of Aminosilan XL 972 were added, the temperature increasing and the viscosity increasing massively. After addition of 2% vinyltrimethoxysilane, the product was filled and sealed watertight. The viscosity was 23 ° C outside the Measuring range and thus far above 2000 Pas

Preparation of foamable mixtures:

In an aerosol can was the isocyanatosilane of Example 3 with polyol, Propellant (mixture of DME and propane butane), flame retardant, Catalyst, reactive diluents and foam stabilizer filled. The The can was closed with a valve and the contents shaken completely mixed. The actual prepolymer synthesis took place in the aerosol can.

Further Foamable mixtures according to the invention were from the isocyanatosilanes of Examples 4 and 5 in analog Meadow made. As a polyol, among other things, the Stepanpol PD 190LV from the company Stepan.

The Viscosity measurement of the foamable mixtures was, as stated above, with substitution of the blowing agent by a mixture of 8.4% methylal and 12.6% pentane (M / P mixture) carried out.

After usual Application of the foamable mixture cures the Foam with the surrounding humidity and was in his Properties rated.

The Results are summarized in the table below (quantities in weight percent). From the data it can be seen that the invention foamable mixtures quickly to foams with good Cure properties.

The Prepolymer of Example 8 was too high viscosity at room temperature or moderate heating in commercial Aerosol cans can be filled.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 96/06124 [0012]
• WO 2000/04069 [0013]
• WO 2002/066532 [0014]
• WO 2005/049684 [0015]
• WO 96/38453 A [0016]
• - US 5866651 A [0017]

Cited non-patent literature

• - DIN 18159 [0002]
• - DIN / EN / ISO 2555 [0035]

Claims (18)

Isocyanate-free foamable mixtures, containing alkoxysilane-terminated prepolymers preparable from Di- or polyisocyanates, polyols and hydroxy- or amino-functional Alkoxysilanes or polyols and isocyanato-functional alkoxysilanes or Mixtures of prepolymers of di- or polyisocyanates, Polyols and hydroxy- or amino-functional alkoxysilanes or from polyols and isocyanato-functional alkoxysilanes with liquid Flame retardants and blowing agents, wherein the prepolymer or the mixture of prepolymer, flame retardant and / or propellant at 23 ° C has a viscosity of 100 to 25,000 mPa · s, preferably 500 to 10,000 mPa · s. Foamable mixtures according to claim 1, characterized in that the alkoxysilane-terminated prepolymer is prepared from di- or polyisocyanates, polyols and compounds having the general formula (1)

wherein m is 0, 1 or 2, R ^{1 is} an alkyl radical having 1 to 4 carbon atoms, R ^{2 is} an alkyl radical having 1 to 4 carbon atoms, R ^{3 is} a divalent organic radical having 1 to 10 atoms selected from C, N, S and / or O in the chain, R ^{4 is} a hydrogen atom or an alkyl group of 1 to 10 carbon atoms and R is a difunctional organic group, or the alkoxysilane-terminated prepolymer is prepared from di- or polyisocyanates, polyols and amino-functional alkoxysilanes. Foamable mixtures according to claim 2, characterized in that R ^{3 has} the following structural elements (2):

wherein n is an integer between 1 and 6, Q is N, O, S, a covalent bond or -NR ^4, and R ⁴ and R ⁵ may independently be a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Foamable mixtures according to claim 1, characterized in that the alkoxysilane-terminated prepolymer can be represented by the general formula (3)

wherein m is 0, 1 or 2, R ^{1 is} an alkyl radical having 1 to 4 carbon atoms, R ^{2 is} an alkyl radical having 1 to 4 carbon atoms, R ^{4 is} a hydrogen atom or an alkyl radical having 1 to 10 carbon atoms and R ^{6 is} a di- or trivalent radical a prepolymer based on polyoxyalkylene glycols. Mixtures according to at least one of the claims 2 to 4, wherein R is a difunctional straight or branched alkyl radical with 2 to 6 carbon atoms. Mixtures according to at least one of the claims 2 to 5, where m is zero. Mixtures according to at least one of the claims 2 to 6, where m is one. Mixtures according to at least one of the claims 1 to 7, characterized in that the hydroxy-functional Alkoxysilane a reaction product of a hydroxyalkyl (meth) acrylate with an aminosilane. Mixtures according to at least one of claims 1 to 8, characterized in that the alkoxysilane-terminated prepolymer having the general formula (3) can be prepared by reacting one or more difunctional and / or trifunctional polyols having an average molecular weight M _n of 400 to 2000 and a isocyanatosilane. Mixtures according to at least one of the claims 1 to 9, characterized in that the isocyanatosilane prepared is by reaction of a hydroxy-functional or amino-functional Alkoxysilane with a diisocyanate. Mixtures according to Claim 10, characterized that the isocyanatosilane at 23 ° C a dynamic viscosity from 50 to 500,000 mPa · s, preferably 100 to 250,000 mPa · s, measured according to DIN / EN / ISO 2555, wherein the Isocyanatosilane is optionally mixed with flame retardants or blowing agents. Mixtures according to at least one of the claims 1 to 11, containing a reactive diluent selected is from methyl, vinyl, and phenyltrimethoxysilane and / or their Partial hydrolyzates and mixtures thereof in concentrations> 1% based on the Prepolymer. Mixtures according to at least one of the claims 1 to 12, where the blowing agent is selected from Hydrocarbons and fluorohydrocarbons each having 1-5 Carbon atoms and dimethyl ether and mixtures thereof. Mixtures according to at least one of the claims 1 to 13, characterized in that the flame retardant selected is selected from the group brominated ethers (ixol), brominated alcohols, in particular dibromoneopentyl alcohol, tribromoneopentyl alcohol and PHT-4-diol, organic phosphates, especially diethyl ethane phosphonate (DEEP), triethyl phosphate (TEP), dimethyl propyl phosphonate (DMPP), Diphenyl cresyl phosphate (DPK), as well as chlorinated phosphates, in particular Tris (2-chloroethyl) phosphate, tris- (2-chloroisopropyl) phosphate (TCPP), Tris (1,3-dichloroisopropyl) phosphate, tris (2,3-dibromopropyl) phosphate and tetrakis (2-chloroethyl) ethylenediphosphate. Mixtures according to at least one of the claims 1 to 14, containing flame retardant in an amount of 1 to 65 wt .-%, particularly preferably from 10 to 65 wt .-%, in particular from 15 to 60% by weight, more preferably between 20 to 50 Wt .-%, based on the total weight of the mixture. Mixtures according to at least one of the claims 1 to 15, containing catalysts selected from titanium (diisopropoxide) bis (acetylacetonate) (TAA), titanium (IV) oxide acetylacetonate, aluminum acetylacetonate, 1,4-diazabicyclo [2,2,2] octane, N, N-dimethylpiperazine, 1,8-diazabicyclo [5.4.0] undec-7-ene, dimorpholino dimethyl ether, Dimorpholinodiethylether (DMDEE) or mixtures thereof in one Amount of 0.01 to about 5 wt .-% based on the total weight of Preparation. Process for the preparation of the isocyanate-free foamable Mixtures according to at least one of Claims 1 to 16, characterized in that the preparation of the prepolymer in Disposable pressure vessels (aerosol cans), if necessary mixed with blowing agents and / or flame retardants. Use of the isocyanate-free foamable Mixtures according to at least one of claims 1 to 16 for sealing, insulating and installing joints, roof surfaces, Windows and doors or to fill cavities.