WO2025176593A1

WO2025176593A1 - Process for producing alkoxysilane-functional polyurethanes and polyurethane ureas

Info

Publication number: WO2025176593A1
Application number: PCT/EP2025/054153
Authority: WO
Inventors: Hans-Josef Laas; Klaus HILLENBRANDT; Winfried Jeske
Original assignee: Covestro Deutschland AG
Current assignee: Covestro Deutschland AG
Priority date: 2024-02-23
Filing date: 2025-02-17
Publication date: 2025-08-28
Anticipated expiration: 2026-08-23
Also published as: EP4606829A1

Abstract

The present invention relates to a process for producing alkoxysilane-containing polyurethanes and/or polyurethane ureas by reacting A1) at least one alkoxysilane-free compound containing at least one isocyanate group and/or B1) at least one alkoxysilane-free compound containing at least one Zerewitinoff-active hydrogen atom with at least one compound containing at least one alkoxysilane group and at least one NCO group and/or B2) at least one compound containing at least one alkoxysilane group and at least one Zerewitinoff-active hydrogen atom in the presence of (C) additives, characterized in that C) comprises tin(II) chloride as catalyst. The invention further relates to the alkoxysilane-containing polyurethanes obtained from the process and to the use thereof.

Description

Process for producing alkoxysilane-functional polyurethanes and polyurethane ureas

The present invention relates to a process for producing alkoxysilane-containing polyurethanes and polyurethane ureas, and also to the alkoxysilane-containing polyurethanes and polyurethane ureas obtained from the process and to the use thereof as binders.

Alkoxysilane-functional (i.e. alkoxysilane-containing) polyurethanes and polyurethane ureas that crosslink via a silane polycondensation have long been known. They are used as moisturecuring single-component systems in the formulation of sealants, adhesives and coating compositions, for example in construction applications or the automotive industry.

Various synthetic routes are known for the production of alkoxysilane-functional polyurethanes and polyurethane ureas, also referred to hereinafter as silane-terminated polyurethanes.

A frequently described process is the reaction of hydroxy-functional compounds with isocyanate-functional alkoxysilanes.

EP-A 0 070 475 describes for example the reaction of isocyanate-containing alkoxysilanes with hydroxy-functional prepolymers in the presence of dibutyltin dilaurate (DBTL) as catalyst.

According to the teachings of EP-A 0 931 800 and WO 2009/071548 too, hydroxy-functional polyurethane prepolymers obtained by reacting diisocyanates with excess amounts of diols can be converted into silane-terminated polyurethanes with isocyanatosilanes. In these processes too, the catalysts used are preferably tin-containing compounds, such as DBTL in particular.

EP-A 1 924 621 , WO 99/55794 and WO 2012/168234 describe alkoxysilane-terminated polyurethanes produced by DBTL-catalyzed reaction of polyether polyols of varying molecular weights with isocyanatoalkylalkoxysilanes.

Another long-known synthetic route for the production of silane-terminated polyurethanes consists of the reaction of isocyanate-functional prepolymers with amino-functional alkoxysilanes.

EP-A 1 093 482 and US 3 632 557 describe for example the reaction of polyether polyols with a molar excess of diisocyanates to afford polyurethanes having terminal isocyanate groups and the reaction thereof with primary aminosilanes, for example 3- aminopropyltrimethoxysilane, to afford alkoxysilane-functional polyurethane ureas.

The subject matter of US 3 627 722 is a similar process, in which secondary aminosilanes, for example N-methylaminopropyltrimethoxysilane, are reacted with isocyanate prepolymers. In the processes described in WO 2011/023691 and WO 2011/069968, silane-functional aspartic esters, for example the diethyl N-(3-trimethoxysilylpropyl)aspartate known from EP-A 0 596 360, serve as reactants for isocyanate-functional polyurethane prepolymers.

However, all processes for producing alkoxysilane-functional polyurethane ureas using aminosilanes have the disadvantage that the process products have very high viscosities on account of the urea groups formed during their production, which makes them considerably more difficult to process.

This disadvantage can be partially averted by combining the two synthetic routes described above into a hybrid process in which a polyol is reacted with a diisocyanate, an isocyanatosilane and an aminosilane. Such processes for producing mixed silane-terminated polyurethane ureas having reduced viscosity are disclosed for example in AU 2015100195, WO 2019/122174 and WO 2020/239663.

However, what the above-described processes for producing silane-terminated polyurethanes using isocyanate-functional alkoxysilanes all have in common is that the reaction times need to be as short as possible in order to prevent or at least minimize possible transesterification reactions between alkoxysilane groups and hydroxyl groups of the employed polyol present at the same time in the reaction mixture.

The majority of the abovementioned processes employ for this purpose organotin compounds known from polyurethane chemistry as highly effective urethanization catalysts, such as dialkyltin dialkoxides and dialkanoates, in particular DBTL. However, because of their unfavourable toxicological profile, in particular their reproductive toxicity and mutagenicity, organotin compounds are facing mounting criticism.

There has accordingly been no lack of attempts to find alternative, nontoxic catalysts suitable for the production of silane-terminated polyurethanes.

EP-A 1 535 940 describes for example a process for producing silane-terminated polyether urethanes, in which long-chain polyether polyols are reacted with isocyanatoalkylalkoxysilanes in the presence of bismuth and zinc catalysts, for example bismuth neodecanoate or zinc-2- ethylhexanoate. The catalytic activity of bismuth and zinc catalysts is however significantly lower than that of organotin compounds, which is why higher catalyst concentrations need to be used. However, this can adversely affect the storage stability of silane-terminated polyurethanes in industry.

Moreover, a general disadvantage of bismuth catalysts is that they decompose during prolonged storage and especially under the influence of daylight, commonly resulting in a brown discoloration or even precipitation of black particles in the product (D. Guhl, FAPU 49, 30-33 (2008), DOI: 10-1386-08-EPJ-2-2008-d.indd). WO 2018/113937 describes this effect for silane-terminated prepolymers.

The potassium, iron, indium, zinc, bismuth and copper compounds, for example potassium neodecanoate, indium neooctanoate, copper naphthenate or iron naphthenate, described in WO 2009/133061 and WO 2009/133062 as suitable catalysts for the production of silane- terminated polymers likewise show inadequate activity by comparison with organotin catalysts and likewise sometimes cause discoloration in the product.

WO 2019/121239 describes the use of special thermolatent tin catalysts for the production of alkoxysilane-containing polyurethanes. These catalysts contain inorganically bound tin and are accordingly largely harmless from a toxicological viewpoint. However, their catalytic activity is significantly lower than that of DBTL, which makes it necessary to use very high catalyst concentrations. An additional disadvantage of the thermolatent catalysts from WO 2019/121239 is their low solubility in common solvents, which makes them difficult to use in industry.

The disadvantage of very low solubility is exhibited also by the lanthanoid complexes with p- diketone ligands, for example ytterbium(lll) acetylacetonate, proposed as catalysts in WO 2019/121351.

The catalysis of urethanization reactions in the production of silane-terminated polyurethanes has yet to be satisfactorily resolved. There was therefore a need for an organotin-free catalyst that has at least the same activity, preferably better activity, than the organotin catalysts currently used in industry, such as DBTL in particular, and has no adverse effect on the viscosity, stability, colour and processability of the product.

As has now surprisingly been found, the inorganic tin compound ti n ( 11) chloride shows excellent suitability as a catalyst for the production of alkoxysilane-containing polyurethanes and/or polyurethane ureas. The use of even very small amounts of tin(ll) chloride as catalyst affords, within short reaction times and at low temperatures, light-coloured products that are in no way inferior in their storage stability, viscosity and processability to those produced under DBTL catalysis.

The present invention provides a process for producing alkoxysilane-containing polyurethanes and/or polyurethane ureas by reacting

A1) at least one alkoxysilane-free compound containing at least one isocyanate group and/or

B1) at least one alkoxysilane-free compound containing at least one Zerewitinoff-active hydrogen atom with A2) at least one compound containing at least one alkoxysilane group and at least one NCO group and/or

B2) at least one compound containing at least one alkoxysilane group and at least one Zerewitinoff-active hydrogen atom in the presence of

(C) additives, characterized in that C) comprises tin(ll) chloride as catalyst.

The invention also provides for the alkoxysilane-containing polyurethanes and/or polyurethane ureas obtainable by this process and for the use thereof as binders for paint, sealant or adhesive raw materials.

Suitable starting compounds A1) for the process according to the invention are alkoxysilane- free compounds that have at least one NCO group. These are for example diisocyanates having ali phatically, cycloaliphatically, araliphatically and/or aromatically attached isocyanate groups, which are obtainable in various ways, for example by phosgenation of the corresponding diamines in the liquid or gas phase or by a phosgene-free route, such as thermal urethane cleavage for example. Suitable diisocyanates A1) are in particular those in the 140 to 400 g/mol molecular weight range, for example 1 ,4-diisocyanatobutane, 1 ,5- diisocyanatopentane (PDI), 1 ,6-diisocyanatohexane (HDI), 2-methyl-1 ,5-diisocyanatopentane, 1 ,5-diisocyanato-2,2-dimethylpentane, 2,2,4- or 2,4,4-trimethyl-1 ,6-diisocyanatohexane, 1 ,10- diisocyanatodecane, 1 ,3- and 1 ,4-diisocyanatocyclohexane, 2,4- and 2,6-diisocyanato-1- methylcyclohexane, 1 ,3- and 1 ,4-bis(isocyanatomethyl)cyclohexane, 1-isocyanato-3,3,5- trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, I PDI), 4,4'- diisocyanatodicyclohexylmethane, 2,4'-diisocyanatodicyclohexylmethane, 1-isocyanato-1- methyl-4(3)-isocyanatomethylcyclohexane, bis(isocyanatomethyl)norbornane, 1 ,3- and 1 ,4- bis(isocyanatomethyl)benzene (XDI), 1 ,3- and 1 ,4-bis(2-isocyanatoprop-2-yl)benzene (TMXDI), 2,4- and 2,6-diisocyanatotoluene (TDI), 2,4'- and 4,4'-diisocyanatodiphenylmethane (MDI), 1 ,5-diisocyanatonaphthalene, or any desired mixtures of such diisocyanates.

Suitable starting compounds A1) are also polyisocyanates obtainable by modification of these diisocyanates and having uretdione, isocyanurate, iminooxadiazinedione, urethane, allophanate, biuret and/or oxadiazinetrione structures.

Preference as alkoxysilane-free starting components A1) is given to the recited diisocyanates, particularly preferably those having aliphatically and/or cycloaliphatically attached isocyanate groups, and very particularly preferably 1 ,5-diisocyanatopentane, 1 ,6-diisocyanatohexane, 1- isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane and 2,4'- and/or 4,4'- diisocyanatodicyclohexylmethane.

Suitable starting compounds A2) for the process according to the invention are any compounds in which at least one, preferably just one, isocyanate group and at least one, preferably just one, silane group having at least one alkoxy substituent are simultaneously present alongside one another. These isocyanatosilanes are hereinafter referred to also as alkoxysilane- functional isocyanates or as isocyanatoalkoxysilanes.

Isocyanatoalkoxysilanes suitable as starting compounds A2) are for example those obtainable e.g. according to the phosgene-free processes described in IIS-B 3494 951 , EP-A 0649 850, WO 2014/063 895 and WO 2016/010 900 through thermal cleavage of the corresponding carbamates or ureas.

As alkoxysilane-functional isocyanate in the process according to the invention, preference is given to using at least one compound of the general formula (I)

R¹

R²-Si-X— NCO

R³ (I) in which

R¹, R² and R³ are each independently identical or different saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 18 carbon atoms, which may optionally contain up to 3 heteroatoms from the group of oxygen, sulfur, nitrogen, preferably in each case alkyl radicals having up to 6 carbon atoms and/or alkoxy radicals having up to 6 carbon atoms, which may contain up to 3 oxygen atoms, particularly preferably in each case methyl, methoxy and/or ethoxy, with the proviso that at least one of the radicals R¹, R² and R³ is attached to the silicon atom via an oxygen atom, and

X is a linear or branched organic radical having up to 6, preferably 1 to 4, carbon atoms, particularly preferably a propylene radical (-CH2-CH2-CH2-).

Examples of such isocyanatoalkoxysilanes include isocyanatomethyltrimethoxysilane, isocyanatomethylmethyldimethoxysilane, isocyanatomethyltriethoxysilane, isocyanatomethylmethyldiethoxysilane, isocyanatomethyltriisopropoxysilane, 2- isocyanatoethyltrimethoxysilane, 2-isocyanatoethyltriethoxysilane, 2- isocyanatoethyltriisopropoxysilane, 3-isocyanatopropyltrimethoxysilane, 3- isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldimethoxysilane, 3- isocyanatopropylmethyldiethoxysilane, 3-isocyanatopropylethyldiethoxysilane, 3- isocyanatopropyldimethylethoxysilane, 3-isocyanatopropyldiisopropylethoxysilane, 3- isocyanatopropyltripropoxysilane, 3-isocyanatopropyltriisopropoxysilane, 3- isocyanatopropyltributoxysilane, 3-isocyanatopropylmethyldibutoxysilane, 3- isocyanatopropylphenyldimethoxysilane, 3-isocyanatopropylphenyldiethoxysilane, 3- isocyanatopropyltris(methoxyethoxyethoxy)silane, 2-isocyanatoisopropyltrimethoxysilane, 4- isocyanatobutyltrimethoxysilane, 4-isocyanatobutyltriethoxysilane, 4- isocyanatobutyltriisopropoxysilane, 4-isocyanatobutylmethyldimethoxysilane, 4- isocyanatobutylmethyldiethoxysilane, 4-isocyanatobutylethyldimethoxysilane, 4- isocyanatobutylethyldiethoxysilane, 4-isocyanatobutyldimethylmethoxysilane, 4- isocyanatobutylphenyldimethoxysilane, 4-isocyanatobutylphenyldiethoxysilane, 4- isocyanato(3-methylbutyl)trimethoxysilane, 4-isocyanato(3-methylbutyl)triethoxysilane, 4- isocyanato(3-methylbutyl)methyldimethoxysilane, 4-isocyanato(3- methylbutyl)methyldiethoxysilane and 11-isocyanatoundecyltrimethoxysilane or any desired mixture of such isocyanatoalkoxysilanes.

Further suitable starting compounds A2 for the process according to the invention are also isocyanatosilanes having a thiourethane structure, such as can be obtained according to the process in WO 2014/037279 by reaction of any aliphatic, cycloaliphatic, araliphatic or aromatic diisocyanate of the recited type with any mercaptosilane in an NCO:SH ratio of 6:1 to 40:1 and subsequent removal of excess unreacted monomeric diisocyanates by thin-film distillation.

Suitable isocyanatoalkoxysilanes A2) likewise include for example those having a formylurea structure such as can be obtained according to the process of WO 2015/113923 by reaction of formamide-containing silanes with a molar excess of any aliphatic, cycloaliphatic, araliphatic or aromatic diisocyanate of the recited type and subsequent distillative removal of unreacted monomeric diisocyanates.

Further suitable isocyanatoalkoxysilanes A2) are finally also the 1 :1 monoadducts obtainable for example by the process of EP-A 1 136 495 from di isocyanates of the recited type and specific secondary aminoalkylalkoxysilanes, in particular the aspartic esters known from EP-A 0 596 360 and obtainable by reaction of dialkyl maleates with aminosilanes, in which the reactants are reacted with one another using a large molar excess of isocyanate, with subsequent distillative removal of unreacted monomeric diisocyanates.

Preferred starting compounds A2) for the process according to the invention are in particular isocyanatomethyltrimethoxysilane, isocyanatomethyltriethoxysilane, (isocyanatomethyl)methyldimethoxysilane, (isocyanatomethyl)methyldiethoxysilane, 3- isocyanatopropyltrimethoxysilane, 3-isocyanatopropylmethyldimethoxysilane, 3- isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane and any desired mixtures of such isocyanatosilanes. Particular preference is given to using 3- isocyanatopropyltrimethoxysilane.

Suitable starting compounds B1) for the process according to the invention are any alkoxysilane-free compound having at least one Zerewitinoff-active hydrogen atom.

Suitable alkoxysilane-free compounds B1) are for example polyols, such as the polymeric polyether polyols, polyester polyols, polycarbonate polyols, polyurethane polyols and/or polyacrylate polyols known from polyurethane chemistry, which usually have an average functionality of from 1.8 to 6, preferably 1.8 to 4, particularly preferably from 1.9 to 2.2. The number-average molecular weight of these polyols (determined in accordance with DIN 55672- 1 :2016-03) is generally from 3000 to 24 000, preferably from 5000 to 16 000, particularly preferably from 7000 to 12 000. It is also possible to use any desired mixtures of such polyols as starting compounds B1).

The water content of suitable polyols B1) for the process according to the invention is usually not more than 500 ppm, preferably not more than 300 ppm, particularly preferably from 50 to 250 ppm. The water content can if necessary also be reduced to < 50 ppm by appropriate measures, for example by applying vacuum and optionally heating to a temperature in the range from 80 to 100°C.

The polyols suitable as alkoxysilane-free starting compounds B1) usually have OH values, determined in accordance with DIN 53240-2:2007-11 , of at least 4.5 mg KOH/mg, preferably of from 8 to 30 mg KOH/g, particularly preferably from 8 to 20 mg KOH/g, most preferably from 9 to 18 mg KOH/g.

Preferred polyol components B1) for the process according to the invention are polyether polyols, for example those of the type mentioned in DE 26 22 951 B, column 6, line 65 to column 7, line 26, EP-A 0 978 523, page 4, line 45 to page 5, line 14, or WO 2011/069 966, page 4, line 20 to page 5, line 23, provided they meet the above specifications regarding functionality and molecular weight. Polyether polyols that are particularly preferred as polyol components B1) are products of the addition of ethylene oxide and/or propylene oxide to propane-1 , 2-diol, propane-1 , 3-diol, glycerol, trimethylolpropane, ethylenediamine and/or pentaerythritol, or the polytetramethylene ether glycols in the abovementioned molecular weight range that are obtainable by polymerizing tetrahydrofuran. Very particularly preferred polyol components B1) are polyether polyols based on polypropylene oxide, such as are commercially available for example from Covestro Deutschland AG under the Acclaim® trade name, for example Acclaim® 8200 N.

Suitable starting compounds B2) are those that contain at least one Zerewitinoff-active hydrogen atom and at the same time at least one alkoxysilane group. These include for example any desired amino- and/or mercaptosilanes.

Suitable aminosilanes B2) are for example aminosilanes of the general formula (II) in which

R¹, R², R³ and X are as defined for formula (I) and

R⁴ is hydrogen, a saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic radical or optionally substituted aromatic or araliphatic radical having up to 18 carbon atoms or a radical of the formula in which R¹, R², R³ and X are as defined above. aminosilanes of the general formula (II) are for example 3- aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3- aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3- aminopropylethyldiethoxysilane, 3-aminopropyldimethylethoxysilane, 3- aminopropyldiisopropylethoxysilane, 3-aminopropyltripropoxysilane, 3- aminopropyltributoxysilane, 3-aminopropylphenyldiethoxysilane, 3- aminopropylphenyldimethoxysilane, 3-aminopropyltris(methoxyethoxyethoxy)silane 2- aminoisopropyltrimethoxysilane, 4-aminobutyltrimethoxysilane, 4-aminobutyltriethoxysilane, 4-aminobutylmethyldimethoxysilane, 4-aminobutylmethyldiethoxysilane, 4- aminobutylethyldimethoxysilane, 4-aminobutylethyldiethoxysilane, 4- aminobutyldimethylmethoxysilane, 4-aminobutylphenyldimethoxysilane, 4- ammobutylphenyldiethoxysilane, 4-ammo(3-methylbutyl)methyldimethoxysilane, 4-amino(3- methylbutyl)methyldiethoxysilane, 4-amino(3-methylbutyl)trimethoxysilane, 3- aminopropylphenylmethyl-n-propoxysilane, 3-aminopropylmethyldibutoxysilane, 3- aminopropyldiethylmethylsilane, 3-aminopropylmethylbis(trimethylsiloxy)silane, 11- aminoundecyltrimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, N-methyl-3- aminopropyltriethoxysilane, N-(n-butyl)-3-aminopropyltrimethoxysilane, N-(n-butyl)-3- aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2- aminoethyl)-3-aminoisobutylmethyldimethoxysilane, N-(2-aminoethyl)-3- aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltris(2-ethylhexoxy)silane, N-(6-aminohexyl)-3-aminopropyltrimethoxysilane, N-benzyl-N-(2-aminoethyl)-3- aminopropyltrimethoxysilane, bis(3-trimethoxysilylpropyl)amine, bis(3- triethoxysilylpropyl)amine, (aminoethylaminomethyl)phenethyltrimethoxysilane, N-vinylbenzyl- N-(2-aminoethyl)-3-aminopropylpolysiloxane, N-vinylbenzyl-N-(2-aminoethyl)-3- aminopropylpolysiloxane, 3-ureidopropyltriethoxysilane, 3-(m- aminophenoxy)propyltrimethoxysilane, m- and/or p-aminophenyltrimethoxysilane, 3-(3- aminopropoxy)-3,3-dimethyl-1 -propenyltrimethoxysilane, 3- aminopropylmethylbis(trimethylsiloxy)silane, 3-aminopropyltris(trimethylsiloxy)silane, 3- aminopropylpentamethyldisiloxane or any desired mixtures of such aminosilanes.

Preferred aminosilanes of the general formula (II) are those in which

R¹, R² and R³ are each alkyl radicals having up to 6 carbon atoms and/or alkoxy radicals containing up to 3 oxygen atoms, with the proviso that at least one of the radicals R¹, R² and R³ is an alkoxy radical of this kind,

X is a linear or branched alkylene radical having 3 or 4 carbon atoms, and

R⁴ is a saturated, linear or branched, aliphatic or cycloaliphatic radical having up to 6 carbon atoms or a radical of formula in which R¹, R², R³ and X are as defined above.

Particularly preferred aminosilanes of the general formula (II) are those in which R¹, R² and R³ are each methyl, methoxy and/or ethoxy, with the proviso that at least one of the radicals R¹, R² and R³ is a methoxy or ethoxy radical,

X is a propylene radical (-CH2-CH2-CH2-), and

R⁴ is a linear alkyl radical having up to 4 carbon atoms or a radical of formula in which R¹, R², R³ and X are as defined above.

Very particularly preferred aminosilanes of the general formula (II) are N-methyl-3- aminopropyltrimethoxysilane, N-methyl-3-aminopropyltriethoxysilane, N-(n-butyl)-3- aminopropyltrimethoxysilane, N-(n-butyl)-3-aminopropyltriethoxysilane, bis(3- trimethoxysilylpropyl)amine and/or bis(3-triethoxysilylpropyl)amine.

Suitable aminosilanes are for example also those of the general formula (III) in which R¹, R² and R³ are as defined for formula (II),

X is a linear or branched organic radical having at least 2 carbon atoms and

R⁵ and R⁶ are each independently saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or aromatic organic radicals having 1 to 18 carbon atoms, which are substituted or unsubstituted and/or have heteroatoms in the chain.

These aminosilanes of the general formula (III) are the silane-functional aspartic esters obtainable according to the teaching of EP-A 0 596 360 obtainable by reacting aminosilanes bearing primary amino groups with fumaric esters and/or maleic esters.

Suitable starting compounds for producing aminosilanes of the general formula (III) are therefore in principle any aminosilanes of the general formula (II) in which R¹, R², R³ and X are as defined for formula (II) and R⁴ is hydrogen. These are reacted with fumaric diesters and/or maleic diesters of the general formula (IV)

R⁵OOC-CH = CH-COOR⁶ (iv), in which the radicals R⁵ and R⁶ are identical or different radicals and are organic radicals having 1 to 18, preferably 1 to 9, particularly preferably 1 to 4, carbon atoms.

Preferred aminosilanes of the general formula (III) are reaction products of aminosilanes of the general formula (II) in which

R¹, R² and R³ are each methyl, methoxy and/or ethoxy, with the proviso that at least one of the radicals R¹, R² and R³ is a methoxy or ethoxy radical,

X is a propylene radical (-CH2-CH2-CH2-), and

R⁴ is hydrogen, with fumaric diesters and/or maleic diesters of the general formula (IV) in which the radicals R⁵ and R⁶ are identical or different radicals and are a methyl, ethyl, n-butyl or 2-ethylhexyl radical.

Particularly preferred aminosilanes of the general formula (III) are reaction products of 3- aminopropyltrimethoxysilane and/or 3-aminopropyltriethoxysilane with diethyl maleate.

Further suitable aminosilanes for the process according to the invention are for example also those of the general formula (V) in which R¹, R² and R³ are as defined for formula (II),

X is a linear or branched organic radical having at least 2 carbon atoms and

R⁷ is a saturated linear or branched, aliphatic or cycloaliphatic organic radical having 1 to 8 carbon atoms.

These aminosilanes of the general formula (V) are the known silane-functional alkylamides as can be obtained for example according to the methods disclosed in US 4 788 310 and US 4 826 915 by reacting aminosilanes bearing primary amino groups with alkyl alkylcarboxylates with elimination of alcohol.

Suitable starting compounds for producing aminosilanes of the general formula (V) are therefore in principle any aminosilanes of the general formula (II) in which R¹, R², R³ and X are as defined for formula (II) and R⁴ is hydrogen.

These are reacted with alkyl alkylcarboxylates of the general formula (VI)

R⁸ - COOR⁹ (VI), in which

R⁸ is hydrogen or a saturated linear or branched, aliphatic or cycloaliphatic organic radical having 1 to 8 carbon atoms and

R⁹ is a saturated aliphatic organic radical having 1 to 4 carbon atoms.

Preferred aminosilanes of the general formula (V) are reaction products of aminosilanes of the general formula (II) in which

X is a propylene radical (-CH2-CH2-CH2-), and

R⁴ is hydrogen, with alkyl formates of the general formula (VI) in which

R⁸ is hydrogen and

R⁹ is a saturated aliphatic organic radical having 1 to 4 carbon atoms.

Particularly preferred aminosilanes of the general formula (V) are reaction products of 3- aminopropyltrimethoxysilane and/or 3-aminopropyltriethoxysilane with methyl formate and/or ethyl formate.

In addition to the recited aminosilanes B2), mercaptosilanes are also suitable starting compounds B2) for the process according to the invention.

These are mercaptosilanes of the general formula (VII) in which

R¹, R², R³ and X are as defined for formula (I).

Suitable mercaptosilanes B2) are for example 2-mercaptoethylmethyldimethoxysilane, 2- mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3- mercaptopropylmethyldimethoxysilane, 3-mercaptopropyldimethylmethoxysilane, 3- mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, 3- mercaptopropyltriethoxysilane, 3-mercaptopropylethyldimethoxysilane, 3- mercaptopropylethyldiethoxysilane and/or 4-mercaptobutyltrimethoxysilane.

In a particular embodiment, components A1) and/or B1) are used in an amount such that the sum total of components A1) and/or B1) is 40% to 99% by weight, preferably 60% to 98.5% by weight, particularly preferably 70% to 98% by weight and very particularly preferably 85% to 97% by weight, in each case based on the sum total of the masses of A1), B1), A2), B2) and C).

In another particular embodiment, components A2) and/or B2) are used in an amount such that the sum total of components A2) and/or B2) is 0.5% to 20% by weight, preferably 1.0% to 10% by weight, particularly preferably 1.5% to 8% by weight and very particularly preferably 2.0% to 6.0% by weight, in each case based on the sum total of the masses of A1), B1), A2), B2) and C).

Additives C) used according to the invention are compounds that are necessary in order to obtain the desired product from the reaction of components A1) and/or B1) with A2) and/or B2). These include for example catalysts or isocyanate-reactive compounds, for example monofunctional alcohols, for adjusting the final NCO contents. According to the invention, at least tin(ll) chloride as catalyst is used as an additive, preferably only tin(ll) chloride is used as catalyst. The sum total of the additives C) used is preferably at least 0.0005% by weight, particularly preferably 0.001% to 10% by weight, very particularly preferably 0.002% to 5% by weight and most preferably 0.002% to 1 % by weight, in each case based on the sum total of the masses of A1), B1), A2), B2) and C).

In a particular embodiment, only catalysts and monofunctional alcohols are used as additives C).

For the performance of the process of the invention, at least one alkoxysilane-free compound A1) containing at least one isocyanate group and/or at least one alkoxysilane-free compound B1) containing at least one Zerewitinoff-active hydrogen atom is reacted with at least one compound A2) containing at least one alkoxysilane group and at least one isocyanate group and/or at least one compound B2) containing at least one alkoxysilane group and at least one Zerewitinoff-active hydrogen atom in any desired order, preferably at temperatures of from 20 to 120°C, particularly preferably from 30 to 80°C, very particularly preferably from 40 to 60°C, observing an equivalents ratio of isocyanate groups to Zerewitinoff-active hydrogen atoms of from 0.8:1 to 1.5:1 , preferably from 1 :1 to 1.5:1 , particularly preferably 1 :1 to 1.2:1 , in the presence of tin(ll) chloride as catalyst.

The tin(ll) chloride used here may either be anhydrous, but preferably in the form of its dihydrate. The catalyst can be added to the reaction mixture solvent-free in the form of the bulk substance, or it can be added dissolved in a suitable solvent.

Examples of suitable catalyst solvents are the customary paint solvents that are known per se, for example ethyl acetate, butyl acetate, ethylene glycol monomethyl or monoethyl ether acetate, 1-methoxy-2-propyl acetate, 3-methoxy-n-butyl acetate, acetone, 2-butanone, 4- methyl-2-pentanone, cyclohexanone, toluene, xylene, chlorobenzene, white spirit, more highly substituted aromatics of the kind sold for example under the names solvent naphtha, Solvesso®, Isopar®, Nappar® (Deutsche Exxon Chemical GmbH, Cologne, Germany), and Shellsol® (Deutsche Shell Chemie GmbH, Eschborn, Germany), but also solvents such as ethylene glycol, diethylene glycol, propylene glycol, propylene glycol diacetate, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, diethylene glycol ethyl and butyl ether acetate, N-methylpyrrolidone, and N-methylcaprolactam, or any desired mixtures of such solvents.

Also suitable as catalyst solvents are the polyols described above as alkoxysilane-free starting compounds B1), very particularly preferably polyether polyols based on polypropylene oxide. If a compound B1) is being used as solvent for a catalyst, i.e. the catalyst is dissolved in the solvent prior to addition to component A1), B1), A2) and/or B2), then the mass of compound B1) used as a solvent is added to the mass of additives C).

Irrespective of the nature of the addition, whether it be solvent-free or as a solution, tin(ll) chloride is preferably employed in the process of the invention in an amount of from 0.0005% to 0.1 % by weight, particularly preferably from 0.001% to 0.02% by weight, very particularly preferably from 0.002% to 0.01 % by weight, in each case calculated as the active substance tin(ll) chloride based on the total weight of reactants A1), A2), B1) and B2).

In one possible embodiment of the process according to the invention, at least one alkoxysilane-free starting compound B1), preferably a polyether polyol ora mixture of polyether polyols, optionally under an inert gas such as nitrogen, is initially charged at a temperature of 20 to 120°C. An alkoxysilane-containing compound A2), preferably an isocyanatosilane or a mixture of isocyanatosilanes, is then added in the amount stated above and the reaction temperature for the urethanization is optionally adjusted by an appropriate measure (heating or cooling) to a temperature of preferably 30°C to 80°C, very particularly preferably of 40°C to 60°C.

In another possible embodiment of the process according to the invention, at least one alkoxysilane-free starting compound B1), preferably a polyether polyol ora mixture of polyether polyols, is initially charged under the above conditions. An alkoxysilane-free isocyanate component A1), preferably a diisocyanate or a mixture of diisocyanates, and an alkoxysilane- functional isocyanate component A2), preferably an isocyanatosilane or a mixture of isocyanatosilanes, is then added in any desired order or in the form of a mixture in the amount stated above and the reaction temperature for the urethanization is optionally adjusted by an appropriate measure (heating or cooling) to a temperature of preferably 30°C to 80°C, very particularly preferably of 40°C to 60°C.

In a further possible embodiment of the process according to the invention, at least one alkoxysilane-free starting compound B1), preferably a polyether polyol ora mixture of polyether polyols, is initially charged under the above conditions. An alkoxysilane-free isocyanate component A1), preferably a diisocyanate or a mixture of diisocyanates, is then first added in molar excess and the reaction temperature for the urethanization is optionally adjusted by an appropriate measure (heating or cooling) to a temperature of preferably 30°C to 80°C, very particularly preferably from 40°C to 60°C. Upon attaining the desired isocyanate content, preferably once all the Zerewitinoff-active hydrogen atoms of component B1) have reacted, an alkoxysilane-containing compound B2), preferably an aminosilane or a mixture of aminosilanes, is added in such an amount that the equivalents ratio of isocyanate groups to Zerewitinoff- active hydrogen atoms of all reactants A1), B1) and B2) meets the above specifications, preferably in such an amount that there are 0.8 to 1.2, preferably 0.9 to 1.1 , particularly preferably 0.95 to 1.05, amino groups for each isocyanate group of the polyurethane obtained in the first process step (urethanization).

In a further possible embodiment of the process according to the invention, at least one alkoxysilane-free starting compound B1), preferably a polyether polyol B1) or a mixture of polyether polyols, is initially charged under the above conditions. An alkoxysilane-free isocyanate component A1), preferably a diisocyanate or a mixture of diisocyanates, and an alkoxysilane-functional isocyanate component A2), preferably an isocyanatosilane or a mixture of isocyanatosilanes, is then first added in any desired order or in the form of a mixture in molar excess and the reaction temperature for the urethanization is optionally adjusted by an appropriate measure (heating or cooling) to a temperature of preferably 30°C to 80°C, very particularly preferably of 40°C to 60°C. Upon attaining the desired isocyanate content, preferably once all the Zerewitinoff-active hydrogen atoms of component B1) have reacted, an alkoxysilane-containing compound B2), preferably an aminosilane or a mixture of aminosilanes, is added in such an amount that the equivalents ratio of isocyanate groups to Zerewitinoff- active hydrogen atoms of all reactants A1), A2, B1) and B2) meets the above specifications, preferably in such an amount that there are 0.8 to 1.2, preferably 0.9 to 1.1 , particularly preferably 0.95 to 1.05, amino groups for each isocyanate group of the polyurethane obtained in the first process step (urethanization).

Irrespective of the nature of the reaction regime, the addition of the catalyst tin(l I) chloride to the reaction mixture can take place at any time during the urethanization reaction. It is however also possible for the catalyst to already be mixed into either the alkoxysilane-free starting compounds B1), the alkoxysilane-free isocyanate component A1) and/or the alkoxysilane- functional isocyanate A2) before commencement of the actual reaction.

The course of the reaction in the process according to the invention may be monitored for example by titrimetric determination of the NCO content in accordance with DIN EN ISO 11909:2007-05 or by I R spectroscopy.

In all embodiments of the process according to the invention, the reaction is preferably carried out in such a way that the process products of the invention are free of Zerewitinoff-active hydrogen atoms. Small residual amounts of isocyanate groups may optionally be scavenged by adding compounds reactive to isocyanate groups, for example low-molecular-weight monoalcohols such as methanol or ethanol, preferably in equimolar amounts.

The high catalytic activity of the inorganic tin catalyst tin(ll) chloride makes it possible with the process of the invention, even when using very low catalyst concentrations, to produce practically colourless silane-terminated polyurethanes typically having a colour index of less than 120 APHA, preferably of less than 80 APHA, particularly preferably of less than 60 APHA, in shorter reaction times and at lower temperatures than with the known organotin catalysts of the prior art, in particular DBTL.

The process products of the invention are in no way inferior in their storage stability, viscosity and processability to those obtained under DBTL catalysis. They have excellent suitability as binders for paint, sealant or adhesive raw materials.

In a particular embodiment of the process according to the invention, alkoxysilane-containing polyurethanes and/or polyurethane ureas are obtained by reacting

(C) additives, characterized in that C) comprises tin(ll) chloride as catalyst, wherein the sum total of the masses of A1) and/or B1) is 40% to 99% by weight, preferably 60% to 98.5% by weight, particularly preferably 70% to 98% by weight and very particularly preferably 85% to 97% by weight, the sum total of the masses of A2) and/or B2) is 0.5% to 20% by weight, preferably 1.0% to 10% by weight, particularly preferably 1.5% to 8% by weight and very particularly preferably 2.0% to 6.0% by weight, and the sum total of the masses of C) is at least 0.0005% by weight, preferably 0.001% to 10% by weight, particularly preferably 0.002% to 5% by weight and very particularly preferably 0.002% to 1 % by weight, where stated % by weight values are based on the sum total of the masses of A1), B1), A2), B2) and C) and add up to 100% by weight.

Examples

All percentages are based on weight unless otherwise stated.

NCO contents were determined titrimetrically in accordance with DIN EN ISO 11909:2007-05. The course of the reactions and absence of NCO in the silane-terminated polyurethanes were monitored by the decrease in or absence of the isocyanate band (approx. 2270 cm^-1) in the IR spectrum.

OH values were determined titrimetrically in accordance with DIN 53240-2:2007-11.

Amine values were determined based on DIN EN ISO 9702:1998-10 by potentiometric titration with perchloric acid in glacial acetic acid.

All viscosity measurements were performed with a Physica MCR 51 rheometer from Anton Paar Germany GmbH (Germany) in accordance with DIN EN ISO 3219:1994-10 at a shear rate of 250 s’¹.

The platinum-cobalt colour index was measured spectrophotometrically in accordance with DIN EN ISO 6271-2:2005-03 using a Lico 400 spectrophotometer from Lange, Germany.

Starting compounds

A1-1 : Isophorone diisocyanate

B1-1 : Linear polypropylene ether polyol from Covestro Deutschland AG,

Leverkusen (Acclaim Polyol 22200 N)

OH value titrated: 4.8 mg KOH/g

Equivalent weight: 11 688 g/eq OH

B1-2: Linear polypropylene ether polyol from Covestro Deutschland AG,

Leverkusen (Acclaim Polyol 8200 N)

OH value titrated: 13.8 mg KOH/g

Equivalent weight: 4065 g/eq OH

B1-3: Linear polypropylene ether polyol from Covestro Deutschland AG,

Leverkusen (Acclaim Polyol 18200 N)

OH value titrated: 6.0 mg KOH/g

Equivalent weight: 9350 g/eq OH

A2-1 : 3-lsocyanatopropyltrimethoxysilane (Geniosil® GF 40, Wacker

Chemie AG)

NCO content titrated: 19.5%

Equivalent weight: 215 g/eq NCO B2-1 : Diethyl (3-(trimethoxysilyl)propyl)aspartate produced according to

EP-A 0 596 360, example 5

Amine value titrated: 155.2 mg KOH/g

Equivalent weight: 361.5 g/eq NH

Example 1 (according to the invention)

A stirred vessel with internal thermometer and reflux condenser was initially charged with 1466.4 g (0.125 eq) of B1-1 at 50°C under dry nitrogen and 0.06 g (40 ppm) of a 28% solution of tin(ll) chloride dihydrate (SnCh^FW) in monoethylene glycol, corresponding to an Sn content of 5.8 ppm based on the total amount of the mixture, was added. 30.7 g (0.143 eq) of A2-1 was then added and the reaction mixture stirred further at 50°C until the NCO content was 0.05% after 90 minutes. 0.6 g (0.019 eq) of methanol was then added and the mixture was stirred further at 50°C until, after approx. 60 minutes, an isocyanate band was no longer visible in the IR spectrum.

After cooling to room temperature, an alkoxysilane-containing polyurethane prepolymer was present that had the following characteristics:

Viscosity (23°C): 62 000 mPa-s

Colour index: 16 APHA

NCO content: < 0.03%

Example 2 (comparative)

A stirred vessel with internal thermometer and reflux condenser was initially charged with 1466.4 g (0.125 eq) of B1-1 at 60°C under dry nitrogen and 0.075 g (50 ppm) of dibutyltin dilaurate (DBTL), corresponding to an Sn content of 9.4 ppm based on the total amount of the mixture, was added. 30.7 g (0.143 eq) of A2-1 was then added and the reaction mixture stirred further at 60°C until the NCO content was 0.05% after 3 hours. 0.6 g (0.019 eq) of methanol was then added and the mixture was stirred further at 60°C until, after a further 3 hours, an isocyanate band was no longer visible in the IR spectrum.

Viscosity (23°C): 62 200 mPa s

Colour index: 14 APHA

NCO content: < 0.03% Example 3 (according to the invention)

A stirred vessel with internal thermometer and reflux condenser was initially charged with 1418.6 g (0.349 eq) of B1-2 at 50°C under dry nitrogen and 0.06 g (40 ppm) of a 28% solution of tin(ll) chloride dihydrate (SnCh^FW) in monoethylene glycol, corresponding to an Sn content of 5.8 ppm based on the total amount of the mixture, was added. 78.6 g (0.366 eq) of A2-1 was then added and the reaction mixture stirred further at 50°C until the NCO content was 0.05% after 3 hours. 0.5 g (0.016 eq) of methanol was then added and the mixture was stirred further at 50°C until, after approx. 90 minutes, an isocyanate band was no longer visible in the IR spectrum.

Viscosity (23°C): 6100 mPa-s

Colour index: 16 APHA

NCO content: < 0.03%

Example 4 (comparative)

A stirred vessel with internal thermometer and reflux condenser was initially charged with 1418.6 g (0.349 eq) of B1-2 at 60°C under dry nitrogen and 0.13 g (90 ppm) of dibutyltin dilaurate (DBTL), corresponding to an Sn content of 16.8 ppm based on the total amount of the mixture, was added. 78.6 g (0.366 eq) of A2-1 was then added and the reaction mixture stirred further at 60°C until the NCO content was 0.05% after 4 hours. 0.6 g (0.019 eq) of methanol was then added and the mixture was stirred further at 60°C until, after a further 2 hours, an isocyanate band was no longer visible in the IR spectrum.

Viscosity (23°C): 5700 mPa s

Colour index: 18 APHA

NCO content: < 0.03%

Example 5 (according to the invention)

A stirred vessel with internal thermometer and reflux condenser was initially charged with 1459.9 g (0.156 eq) of B1-3 at 50°C under dry nitrogen and 0.06 g (40 ppm) of a 28% solution of tin(ll) chloride dihydrate (SnCh^FW) in monoethylene glycol, corresponding to an Sn content of 5.8 ppm based on the total amount of the mixture, was added. 37.3 g (0.173 eq) of A2-1 was then added and the reaction mixture stirred further at 50°C until the NCO content was 0.05% after 90 minutes. 0.5 g (0.016 eq) of methanol was then added and the mixture was stirred further at 50°C until, after approx. 60 minutes, an isocyanate band was no longer visible in the IR spectrum.

Viscosity (23°C): 42 500 mPa-s

Colour index: 14 APHA

NCO content: < 0.03%

Example 6 (comparative)

A stirred vessel with internal thermometer and reflux condenser was initially charged with 1459.9 g (0.156 eq) of B1-3 at 50°C under dry nitrogen and 0.075 g (50 ppm) of dibutyltin dilaurate (DBTL), corresponding to an Sn content of 9.4 ppm based on the total amount of the mixture, was added. 37.3 g (0.173 eq) of A2-1 was then added and the reaction mixture stirred further at 50°C until the NCO content was 0.05% after 5 hours. 0.5 g (0.016 eq) of methanol was then added and the mixture stirred at 50°C until, after a further 2 hours, an isocyanate band was no longer visible in the IR spectrum.

Viscosity (23°C): 62 200 mPa s

Colour index: 14 APHA

NCO content: < 0.03%

Example 7 (according to the invention)

A stirred vessel with internal thermometer and reflux condenser was initially charged with

2032.6 g (0.500 eq) of B1-2 at 60°C under dry nitrogen and 0.05 g (22 ppm) of tin(ll) chloride dihydrate (SnCh^FW), corresponding to an Sn content of 11.5 ppm based on the total amount of the mixture, was added. 83.3 g (0.750 eq) of A1-1 and 26.9 g (0.125 eq) of A2-1 were then added and the reaction mixture stirred further at 60°C until, after approx. 2 hours, an NCO content of 0.74% corresponding to complete urethanization had been attained.

135.6 g (0.375 eq) of B2-1 was then quickly added dropwise and the mixture stirred further at 50°C until, after 1 hour, an isocyanate band was no longer visible in the IR spectrum. After cooling to room temperature, an alkoxysilane-containing polyurethane prepolymer was present that had the following characteristics:

Viscosity (23°C): 29200 mPa s

Colour index: 16 APHA

NCO content: < 0.03%

Example 8 (comparative)

A stirred vessel with internal thermometer and reflux condenser was initially charged with 2032.6 g (0.500 eq) of B1-2 at 60°C under dry nitrogen and 0.15 g (65 ppm) of dibutyltin dilaurate (DBTL), corresponding to an Sn content of 11.7 ppm based on the total amount of the mixture, was added. 83.3 g (0.750 eq) of A1-1 and 26.9 g (0.125 eq) of A2-1 were then added and the reaction mixture stirred further at 60°C until, after approx. 4 hours, an NCO content of 0.73% corresponding to complete urethanization had been attained. 135.6 g (0.375 eq) of B2-1 was then quickly added dropwise and the mixture stirred further at 50°C until, after 90 minutes, an isocyanate band was no longer visible in the IR spectrum.

Viscosity (23°C): 29470 mPa-s

Colour index: 16 APHA

NCO content: < 0.03%

Table 1: Overview comparative example

As shown in Table 1 , the use of smaller amounts of the catalyst SnCh of the invention by comparison with DBTL results in a more rapid complete urethanization, even when the reaction temperature in the process using DBTL is increased (examples 1 to 4).

Example 9

The alkoxysilane-containing polyurethane prepolymers from example 5 and comparative example 6 were stored in closed aluminium containers at 50°C for 4 weeks. During this time, the viscosity of the product from example 5 increased by 4.9% to 44600 mPa s and the colour index increased to 15. The viscosity of the product from comparative example 6 increased by 5.8% to 65 800 mPa s and the colour index remained unchanged at 14.

The example shows that products obtained by the process according to the invention using tin(ll) chloride as catalyst are in no way inferior in their storage stability to those produced under DBTL catalysis.

Claims

1 . Process for producing alkoxysilane-containing polyurethanes and/or polyurethane ureas by reacting

B1) at least one alkoxysilane-free compound containing at least one Zerewitinoff- active hydrogen atom with

A2) at least one compound containing at least one alkoxysilane group and at least one NCO group and/or

(C) additives, characterized in that C) comprises tin(ll) chloride as catalyst.

2. Process according to Claim 1 , characterized in that the starting component A1) comprises diisocyanates having aliphatically, cycloaliphatically, araliphatically and/or aromatically attached isocyanate groups.

3. Process according to either of Claims 1 and 2, characterized in that the starting component A1) is 1 ,5-diisocyanatopentane, 1 ,6-diisocyanatohexane, 1-isocyanato- 3,3,5-trimethyl-5-isocyanatomethylcyclohexane and/or 2,4'- and/or 4,4'- diisocyanatodicyclohexylmethane.

4. Process according to any of Claims 1 to 3, characterized in that the starting component A2) comprises compounds in which at least one, preferably just one, isocyanate group and at least one, preferably just one, silane group having at least one alkoxy substituent are present.

5. Process according to any of Claims 1 to 4, characterized in that the starting component A2) is an alkoxysilane-functional isocyanate of the general formula (I) R¹

R²-Si-X— NCO

R³ (I) in which

X is a linear or branched organic radical having up to 6, preferably 1 to 4, carbon atoms, particularly preferably a propylene radical (-CH2- CH2-CH2-).

6. Process according to any of Claims 1 to 5, characterized in that the starting component A2) is isocyanatomethyltrimethoxysilane, isocyanatomethyltriethoxysilane, isocyanatomethylmethyldimethoxysilane, isocyanatomethylmethyldiethoxysilane, 3- isocyanatopropyltrimethoxysilane, 3-isocyanatopropylmethyldimethoxysilane, 3- isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane or any desired mixtures of such isocyanatosilanes.

7. Process according to any of Claims 1 to 6, characterized in that the starting component B1) is a polyether polyol having a number-average molecular weight (determined in accordance with DIN 55672-1 :2016-03) of 3000 to 24 000 g/mol.

8. Process according to any of Claims 1 to 7, characterized in that the starting component B1) is a polyether polyol based on polypropylene oxide.

9. Process according to any of Claims 1 to 8, characterized in that the starting component B2) is an aminosilane of the general formula (II) in which

R¹, R², R³ and X are as defined in Claim 5 and

R⁴ is hydrogen, a saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic radical or optionally substituted aromatic or araliphatic radical having up to 18 carbon atoms or a radical of the formula in which R¹, R², R³ and X are as defined above.

10. Process according to any of Claims 1 to 9, characterized in that the sum total of the masses of A1) and/or B1) is 40% to 99% by weight, preferably 60% to 98.5% by weight, particularly preferably 70% to 98% by weight and very particularly preferably 85% to 97% by weight, the sum total of the masses of A2) and/or B2) is 0.5% to 20% by weight, preferably 1 .0% to 10% by weight, particularly preferably 1.5% to 8% by weight and very particularly preferably 2.0% to 6.0% by weight, and the sum total of the masses of C) is at least 0.0005% by weight, preferably 0.001% to 10% by weight, particularly preferably 0.002% to 5% by weight and very particularly preferably 0.002% to 1 % by weight, where stated % by weight values are based on the sum total of the masses of A1), B1), A2), B2) and C) and add up to 100% by weight.

11 . Process according to any of Claims 1 to 10, characterized in that the starting component B2) is a reaction product of 3-aminopropyltrimethoxysilane and/or 3- aminopropyltriethoxysilane with diethyl maleate.

12. Process according to any of Claims 1 to 11 , characterized in that the at least one component A1) and/or A2) containing at least one NCO group and the at least one compound B1) and/or B2) containing at least one Zerewitinoff-active hydrogen atom are reacted in any desired order, preferably at temperatures of from 20 to 120°C, particularly preferably from 30 to 80°C, very particularly preferably from 40 to 60°C, observing an equivalents ratio of isocyanate groups to Zerewitinoff-active hydrogen atoms of from 0.8:1 to 1.5:1 , preferably from 1 :1 to 1.5:1 , particularly preferably 1 :1 to 1.2:1 , in the presence of tin(ll) chloride as catalyst.

13. Process according to any of Claims 1 to 12, characterized in that the catalyst tin(ll) chloride, which is anhydrous or preferably in the form of its dihydrate, is employed in an amount of from 0.0005% to 0.1 % by weight, preferably from 0.001 % to 0.02% by weight, particularly preferably from 0.002% to 0.01 % by weight, in each case calculated as active substance tin(ll) chloride based on the total weight of reactants A1), A2), B1) and B2).

14. Alkoxysilane-containing polyurethanes and/or polyurethane ureas produced by a process of Claims 1 to 13.

15. Use of the alkoxysilane-containing polyurethanes and/or polyurethane ureas according to Claim 14 as binders for paint, sealant or adhesive raw materials.