A method for preparing a silanised polyurethane prepolymer, its use and a method for producing a moisture-cured silanised one-component foam

Abstract

A method for preparing a silanised polyurethane prepolymer, comprising a process wherein: a) in a first step, an isocyanate prepolymer is prepared by contacting compounds containing at least one hydroxyl group with compounds containing at least two isocyanate groups in the presence of a titanium catalyst in the form of a sol, b) in a second step, a silanising agent is added to the isocyanate prepolymer prepared in the first step. The use of a silanised polyurethane prepolymer to produce an adhesive, sealant, composite, coating. A method for producing a moisture-cured one-component silanised foam, including mixing of: a) the silanised polyurethane prepolymer prepared with the method according to any one of claims 1 - 14, b) a diluent in an amount of 1.0 to 30.0% by weight; c) at least one curing reaction catalyst in an amount of 0.01 to 5.0% by weight; d) at least one surfactant in an amount of 0.1-10.0 % by weight; e) injecting of at least one propellant in an amount of 5 to 35% by weight.

Description

[0001] A method for preparing a silanised polyurethane prepolymer, its use and a method for producing a moisture-cured silanised one-component foam

[0002] The invention relates to a method for preparing a silanised polyurethane prepolymer in the presence of a titanium catalyst in the form of a sol, to the use of a silanised polyurethane prepolymer, to a method for producing a moisture-cured silanised one-component foam, and to a moisture-cured polyurethane polymer prepared from a silanised foam.

[0003] Nowadays, the use of polyurethane foams in the construction industry is widespread. According to their methods of preparation, foams can be divided into one-component and two-component foams. Two-component foams include polyurethane compositions made up of two separate components that are reactive towards each other, after mixing of which a finished product is prepared in situ. Examples of two-component foams are panel boards with metal or plastic cladding used in the construction of warehouse and factory halls, large-scale shops, etc. In turn, one-component foam compositions usually comprise a prepolymer, a mixture of propellant gases and additives mixed together, and are contained in disposable pressurised aerosol cans. One-component foams, also known as assembly foams, are very widely used in the construction industry due to their ease of use and efficiency. They are typically used as a filler material for setting windows or doors in buildings, as a filler material for voids or openings in walls for the installation of, e.g., communal utilities. Due to the chemical nature of the one-component foam, the composition of which usually consists of a polyurethane prepolymer terminated with reactive -NCO groups, highly diluted with propellant gases, plasticisers, stabilisers and excess isocyanate, it can usually be stored for up to 18 months after the date of manufacture. After this time, some gelling may occur, which increases the viscosity of the composition to such an extent that it prevents release of the foam from the container.

[0004] Foam is formed when the contents are released from the can. The prepolymer cures when in contact with air moisture. Often, a certain amount of methylenediphenyl diisocyanate (MDI) originating from the type of isocyanate used - polymeric methylenediphenyl diisocyanate (PMDI) - can also be found in the foam composition. Toxicity to human body organs has been demonstrated for repeated exposure to MDI. In addition, MDI is suspected to cause cancer, to be harmful if inhaled, to irritate the eyes, to provoke respiratory irritation, to cause allergy or asthma symptoms or breathing difficulties if inhaled, and to irritate the skin and cause an allergic skin reaction. A number of risks associated with exposure to MDI monomer makes it necessary to search for alternatives that do not adversely affect the health of the user.

[0005] Such an alternative can be provided by silane polyurethane foams, which cure due to the reaction of the prepolymer-derived silane groups. The process of preparing a prepolymer terminated with silane groups can be carried out in a one- or two-step manner. In the case of the one-step process, alpha- or gamma-isocyanosilanes are used, which react, in the presence of a suitable catalyst, with a polyol or a group of polyols. In the two-step process, a polyol or a group of polyols reacts with a chosen type of isocyanate in the presence of a suitable catalyst. Then, the prepolymer prepared in the first step, terminated with free -NCO groups, is reacted with a chosen type of alpha- or gamma-aminosilane. The result of the described reactions, in both processes, is a prepolymer terminated with silane groups. The silane group is reactive and reacts with water, usually with air moisture, thereby making the foam cure. As a result of this reaction (polycondensation reaction), a short alcohol, usually methanol, is produced. The post-expansion phenomenon typical of traditional polyurethane foams with a reactive -NCO group, associated with the release of carbon dioxide and additional foaming of the composition, is not present here.

[0006] In the process of preparing a silane polyurethane foam composition, by a two-step method, the first step includes the production of the NCO prepolymer. The NCO prepolymer can have a variable viscosity, which is influenced by the (i) specific isocyanate used, (ii) the polyol used (iii) and the selective catalyst, the selectivity of which also depends on the specific process conditions. The relatively low viscosities of the NCO prepolymer are most desirable. They can be achieved when the kinetics of competing reactions of initial chain growth, e.g. the formation of dimers and trimers, i.e. higher oligomers, are reduced. It is well known that asymmetric isocyanates exhibit variable reactivity of NCO groups. Thus, with the use of selective catalysts, the most reactive NCO groups can be used to react with a polyol and the remaining, less reactive NCO groups will minimally undergo further reaction with the formation of higher oligomers.

[0007] EP2011193045 indicates that there is a problem with the formation of allophonates, biurets and cyclotrimerisation, due to the non-selectivity of the catalyst used.

[0008] W WO 2009 / 118112 A3, WO 03 / 033562 Al, WO 03 / 006521 Al and WO 03 / 055929 Al describe a method for synthesising prepolymers by using asymmetric isocyanates to obtain NCO prepolymers characterised by relatively low viscosity. It is obvious to one skilled in the art that the second step in the synthesis of a silanised polyol, i.e. the reaction of the previously prepared NCO prepolymer, with a lower content of higher oligomers, with a silanising agent / amino silane, should ultimately result in a silanised polymer with a correspondingly lower viscosity. This is indirectly confirmed by Klaus Langerbeins' research described in EP2019191328, where as a result of the kinetically controlled reaction of compounds comprising isocyanate groups and polymers with hydroxyl functional groups, polyurethane prepolymers terminated with NCO groups having a relatively narrow molecular weight distribution can be produced. They are characterised by a relatively low dynamic viscosity. In particular, the kinetics of the reaction are determined by reaction parameters such as temperature, type and amount of catalyst and reaction time. The conversion of polyurethane prepolymers according to this invention into silanised polyurethanes does not produce any significant changes in the molecular weight distribution. The process is carried out using a patented, selective catalyst belonging to the following groups: metallosiloxane silanol compounds, organometallic compounds of aluminium, tin, zinc, titanium, manganese, iron, bismuth or zirconium, also from the tertiary amine group, or mixtures thereof. The use of a typical dibutyltin dilaurate (DBTDL) catalyst resulted in a lack of selectivity and in preparing an NCO prepolymer characterised by a relatively high dynamic viscosity.

[0009] US365145B2 discloses a method for preparing silanised prepolymers with the use of DBTDL, dibutyltin dilaurate, catalyst containing tin. The described process is a two-step process. A diol with an MW of 4000 g / mol (Covestro Acclaim 4200) and a mixture of 4,4'-, 2,4'- and 2,2'- methylenediphenyl diisocyanate (Covestro Desmodur TP PU 0129M) were used. The trimethoxy-functional aminosilane Momentive Silquest A-link 15 was used to silanise the prepolymer terminated with -NCO groups, prepared in the first step. In the example described, a very high viscosity of 155000 mPa s at 25°C was achieved. A method for reducing the viscosity of the prepolymer by additionally using, in the prepolymerisation process, other polyols with higher molecular weights is described. Due to the use of the dibutyltin dilaurate, DBTDL, organotin catalyst (with recognised toxicity), following subsequent changes in legislation within the European Union, the use of the technology described in the patent is currently not possible.

[0010] US8232362B2 discloses a method for preparing silanised prepolymers using the bismuth-organic catalyst Vertellus Coscat 83, and compares them to prepolymers prepared on the dibutyltin dilaurate (DBDTL) organotin catalyst Fomrez SUL4. Diols with MWs of 2000, 4000 and 8000 g / mol, Desmodur TP PU 0129M isocyanates and isophorone diisocyanate IPDI were tested. For the silanisation of the prepolymer terminated with NCO groups, prepared in the first step, Momentive Silquest A-link 15 aminosilane and Silquest A-link 35 isocyanate-functional silane (only with a diol of an MW of 2000 g / mol) were used. Prepolymers not containing the organotin catalyst increased their viscosity over time much more slowly than those containing dibutyltin dilaurate, DBTDL, and did not tend to gell. They were also more resistant to not entirely suitable storage conditions.

[0011] W02015095029A1 discloses a method for preparing silanised prepolymers by means of catalysts containing titanium or zirconium. In the examples, a diol with an MW of 8000 g / mol (Huang Ma) and isophorone diisocyanate, IPDI, (Bayer) were used. The following were used as catalysts in the examples: Tyzor PITA (titanium ethyl acetate complex), Tyzor TPT (tetraisopropyl titanate), Tyzor BTM (alkoxytitanate with 14% titanium content), Tyzor IAM (titanium-based phosphate complex), DBTDL (dibutyltin dilaurate), Coscat 83 (organobismuth in carboxylic acid), K-Kat XC9213 (zirconium dithionate) and Dabco (triethylenediamine). Silquest A-link 35 isocyanate-functional silane was used as the silanising agent. Viscosities ranging from 24000 to 48000 mPa s at 25°C were prepared. The lowest viscosities were prepared with the Tyzor TPT catalyst. In order to improve the colour of the finished prepolymer, an antioxidant in the form of Irganox 1135, methanol and triphenyl phosphate were added. The titanium compound-based catalysis solution used in W02015095029A1, while giving the lowest viscosity of the prepolymer tested in this patent, still yields a viscosity approximately twice that of the present solution.

[0012] W02018029420A1 discloses a method for preparing prepolymers by a 3-step process using zinc and bismuth catalysts (Borchi KAT® VP0244 / Zn, Bi / ; Borchi KAT® 0761 / based on zinc neodecanates). A diol with an MW of 4000 g / mol (Voranol® EP 1900) was used as the polyol in the first step. 2,4-toluene diisocyanate, TDI, and isophorone diisocyanate, IPDI, were used as the isocyanates. Momentive Silquest® Al- 1100 (gamma-aminopropyltriethoxysilane) was used as the silanising agent to partially saturate the -NCO groups. In the 3rd step, the residual NCO groups were finished with a diol with an MW of 400 g / mol. After this step, the viscosity of the prepolymer was reduced, approximately by half, but the viscosities prepared are still very high (120000 mPa s at 25°C).

[0013] WO2019094414A1 discloses a method for preparing silanised prepolymers based on a mixture of a polyol together with an additive intended to increase the mechanical strength of the cured prepolymer. A diol with an MW of 12000 g / mol (Covestro Acclaim 12200) was used as the base polyol. Polymeric tetrahydrofuran with an MW of 1000 g / mol (BASF PolyTHF 1000), SilsurfD 1010 (reactive silicone terminated with polyether groups), KF6000 (carbinol-modified silicone) and a diol with an MW of 1000 g / mol were used as the prepolymerised additives. Isophorone diisocyanate, IPDI, was used as the isocyanate. TIB Cat 216 (dioctyltin dilaurate, DOTL) and Reaxis C216 (dioctyltin dilaurate, DOTL) were used as the catalysts in the examples. The silanising agent was Dynasylate 1189 and 1124. Prepolymer viscosities of 43000 - 64000 mPa s at 25°C were prepared. The prepared prepolymer viscosities are substantially higher than in the method proposed in the solution we have submitted.

[0014] WO20 18200796 Al discloses a method for preparing silane prepolymers based on a diol with an MW of 12000 g / mol (Acclaim 12200), serving as a component of an adhesive formulation. As in the patent described above, DOTL (TIB Cat 216, dioctyltin dilaurate) was used to catalyse the reaction with isophorone diisocyanate, IPDI. A content of 0.75% free -NCO groups was achieved. The silanising agent was Dynasylate 1189. The viscosity of the resulting prepolymer was not given.

[0015] WO2019126246A1 discloses a method for preparing silanised prepolymers based on mixtures of diols of various molecular weights. In each example, one polyol with a high MW of 12000 g / mol (Acclaim 12200) and another with a relatively low weight (Arcol PPG 2000 and Arcol PPG 1000) were used. The reaction was carried out with isophorone diisocyanate, IPDI. The catalyst in all examples was dioctyltin dilaurate (DOTL). The silanising agent in most of the examples was Dynasylan 1189, while in two examples N-(n-Butyl)-3-aminopropyltrimethoxysilane (Onichem Organosilane A301 B), which is equivalent to Dynasylan 1189, was used. Viscosities in the range of 26000 - 71000 mPa s at 25°C were prepared. The lowest viscosity was prepared for the reference example based on Arcol PPG 1000 and the highest for Acclaim 12200. The addition of a shorter polyol resulted in reduced viscosity of the prepolymer. Each time, the viscosities prepared were significantly higher than those we prepared.

[0016] US11236193B2 discloses the same method for preparing a silane prepolymer as in W02018200796A1. It was cited as a reference example. The viscosity of the resulting product in the example was reported to be 70000 mPa- s at 25°C. The main aspect addressed in the patent was the preparing of copolymer-type prepolymers with the use of a second polyol of a lower weight, having a reactive amine group in its structure (Adiansol MA318O, an amine-based diol containing secondary hydroxyl groups, was used). The silanising agent in two examples was Dynasylan 1189, and in one it was Dynasylan 1124. The addition of a second diol to the composition reduced the viscosity from 70000 to 50650 (for Dynasylan 1189) and 38000 mPa s at 25°C (Dynasylan 1124). Each time, the viscosities prepared were significantly higher than those we prepared.

[0017] EP2350178A2 discloses a method for preparing an OCF foam that was made fire- retardant with graphite with the use of silane prepolymers. Thus, the main aspect of this patent is a method for flame retarding one-component foams with the use of expanded graphite and a method for distributing it uniformly in the mass of reactants or prepolymer. In the examples involving silanised one-component foams, a diol with an MW of 400 g / mol (Voranol P400) and 2,4-toluene diisocyanate (TDI) are used as the polyol. The authors do not mention any reaction catalyst in the first step in the examples. In turn, the silanising agent is N- phenylmethyldimethoxy silane (the agent does not contain any reactive amine group). Then, vinyltrimethoxysilane, VTMO, (as an agent capturing water and extending storage time) and a foam stabiliser are added to the prepolymer thus prepared. The prepolymer thus prepared is characterised by a viscosity of 20000 mPa s. Then it is dosed into a pressure container, the valve is tightened and a propellant mixture of suitable composition (propane -butane-dimethyl ether) is dosed.

[0018] US7550517B2 discloses a method for preparing one-component silanised foams from polypropylene glycol of a weight of 425 g / mol and 1 -dodecanol and 2,4- toluene diisocyanate, TDI, and then preparing a silanised prepolymer from the prepared NCO prepolymer and N -phenylaminomethylmethyldimethoxy silane. In this case, no catalyst was used in the first reaction of the polyol with the isocyanate and the reactions were carried out at 80°C. Relatively high viscosities of 8200 mPa- s at 50°C were prepared, which may indicate the involvement of side reactions of biuret and allophonate formation or trimerisation. In another example, a viscosity of 12600 mPa s at 50°C was prepared from the same raw materials with a slightly increased proportion of 1-dodecanone. The foam formulation additionally included a bis[2-(N,N-dimethylamino)ethyl]ether catalyst (Jeffcat® ZF-20 - BDMAEE from Huntsman), aminopropyltrimethoxy silane (Al 110 from Crompton), a silicone stabiliser and a suitable mixture of propellants (propane, butane, dimethylether). The resulting foams are characterised by a very long curing time, a dry touch time of 6 to 10 minutes and a full cross-linking time of 6 hours.

[0019] US7557173B2 shows a method for preparing silanised one-component foams with the use of a tin catalyst, more specifically dibutyltin dilaurate and isocyanate prepolymer based on MDI (Desmodur VKS70), and with the use of 2-ethylhexanol in order to reduce the MDI monomer content. As the silanising agent, Dynasylan 1189 was used. The operating times of the prepared foam were 5 to 60 min for dustfree and 10 min to 8 h for full curing, respectively. In the examples, no other parameters were given for the foams prepared.

[0020] US7674840B2 discloses a method for preparing silanised one-component foams with the use of dibutyltin dilaurate - a reaction catalyst between OH and NCO groups. In the examples provided in the patent, polypropylene glycol of a weight of 425 g / mol and 2,4-toluene diisocyanate (TDI) were used. As the silanising agent, N-phenylaminomethyltrimethoxy silane or N -phenyl- 3- aminopropylmethyltrimethoxysilane was used. Viscosities of 17000 to 21000 mPa- s at 50°C were prepared. The silane prepolymer thus prepared was mixed with foam stabiliser PC STAB EP 05 and an adhesion promoter. The prepared mixture was placed in a glass pressure container provided with a suitable valve and the propellant in the form of 1,1,1,2-tetrafluoroethane was injected. The dust-free time was approx. 1 to 20 min and full curing was achieved after a period of 6 hours to 2 weeks.

[0021] In W02000004069A1, in the examples, bis-(trimethoxysilylpropyl)amine is mentioned as the silanising agent. 2,4-toluene diisocyanate, TDI, and polypropylene glycol of a weight of 400, 1000 or 2000 g / mol were also used as raw materials. A dynamic viscosity of 50000 mPa s was prepared. Full cross-linking times were approx. 24 h. The dust-free time depended on the composition of the foam (two different mixtures of silane prepolymers were used) and was from 5 to 20 min. A mid-to-fine-cellular or fine-cellular foam structure was prepared. The foam was not brittle.

[0022] The aim of the invention is to develop a method for producing a low-viscosity NCO prepolymer. The aim is also to provide a method for producing a one-component polyurethane foam based on NCO prepolymer, which does not contain any toxic methylenediphenyl diisocyanate (MDI) in its composition.

[0023] The object of the invention, in its first aspect, is a method for preparing a silanised polyurethane prepolymer, comprising a process wherein: a) in a first step, an isocyanate prepolymer is prepared by contacting compounds containing at least one hydroxyl group with compounds containing at least two isocyanate groups in the presence of a titanium catalyst in the form of a sol, b) in a second step, a silanising agent is added to the isocyanate prepolymer prepared in the first step.

[0024] Preferably, the titanium catalyst in the form of a sol is prepared by a method comprising the following steps: al) preparing a solution of titanium alcoholate compound in a protic solvent, preferably with a concentration of 1-30% by weight. a2) acidifying the solution prepared in step (al) with an acid, preferably the amount of acid dosed into the solution of the titanium-containing organic compound per 100 g of solution being in the range of 1 mg to 10 g, preferably 1 mg to 100 mg.

[0025] Preferably, the titanium alcoholate is selected from the group including: tetraethyl titanate, di-iso-butoxytitanium chelate (ethyl acetoacetate titanate), tetra-iso-propyl titanate, tetra-n-butyl titanate, tetra-2-ethylhexyl titanate, titanium acetylacetonate, polybutyl titanate, triethanolamine titanate, aqueous titanium chelate, ethyl tetratitanate, tetra-iso-propyl titanate, tetra-n-butyl titanate, preferably tetra-iso- propyl titanate, tetra-n-butyl titanate or tetra-iso-propyl tetratitanate. Preferably, the protic solvent is selected from the group including: methanol, ethanol, propan-2-ol, butan-l-ol, butan-2-ol, 2-methylpropan-2-ol, pentan- l-ol, 3- methylbutan-l-ol, 2-methylbutan-l-ol ol, 2,2-dimethylpropan-l-ol, pentan-3-ol, pentan-2-ol, 3-methylbutan-2-ol, 2-methylbutan-2-ol, hexan-l-ol, hexan-2-ol ol, hexan-3-ol, 2-ethyl-l -hexanol, heptan-l-ol, heptan-2-ol, heptan-4-ol, octan-l-ol, octan-2-ol.

[0026] Preferably, the acid is selected from the group including: boric acid H3BO3, carbonic acid H2CO3, nitrous (nitric(III) acid) HNO2, nitric (V) acid HNO3, phosphonic (phosphorus(III)) acid H3PO3, phosphoric (V) acid H3PO4, sulphurous (sulphuric(IV)) acid H2SO3, sulphuric (sulphuric(VI)) acid H2SO4, chloric (I) acid HC1O, chloric (III) acid HCIO2, chloric (V) acid HCIO3, chloric (VII) acid HC1O4, hydrocyanic acid HCNaq, hydro sulphuric acid H2Saq, hydrofluoric acid HFaq, hydrochloric acid HClaq, hydrobromic acid HBraq, hydroiodic acid HIaq, formic acid HCOOH, acetic acid CH3COOH, citric acid HOOC-CH2-C(OH)(COOH)-CH2- COOH, lactic acid CH3CH(OH)COOH.

[0027] Preferably, in the first step of the prepolymer synthesis, a titanium catalyst solution in the form of a sol, with a concentration in the range of 0.001% to 5.000%, preferably 0.01% to 5.00%, more preferably 0.02% to 0.50% relative to a compound containing at least one hydroxyl group, is used.

[0028] Preferably, in the first step, the molar ratio of a compound containing at least two isocyanate groups to compounds containing at least one hydroxyl group is in the range of 3.00:1.00 to 1.00:1.00, even more preferably 2.50:1:00 to 1.50:1.00, even more preferably 2.25:1.00 to 1.75:1.00, most preferably 2.10:1.00 to 1.90:1.00.

[0029] Preferably, the compound containing at least one hydroxyl group is selected from the group including: poly(oxy)alkylated diols (so-called polyether diols), poly (oxy ethylene)ether diols, poly(oxypropylene)ether diols, poly (oxy ethylene- oxypropylene)ether diols, poly(oxyalkylene)ether diols, poly(oxyalkylene)ether triols (e.g. polyether triols), poly(oxyethylene)ether triols, poly(oxypropylene)ether triols, poly(oxyethylene-oxypropylene)ether triols, poly(tetramethylene)ether glycols, polyacetals, polyhydroxy-polyacrylates, polyhydroxy-polyesteramides, polyhydroxypolithioethers, polycaprolactone diols, polycaprolactonotriols, polybutadienediols .

[0030] Preferably, the compound containing at least two isocyanate groups is selected from the group including: isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, dicyclohexylmethane-4,4' diisocyanate, hexamethylene diisocyanate, bis-(4-isocyanatocyclohexyl)methane and a mixture of 2,4- and 4,4'- diphenylmethane diisocyanates.

[0031] Preferably, the mixture prepared in the first step is stirred at a constant temperature in the range of 15 to 120°C, preferably 20 to 100°C, more preferably 25 to 60°C, for a period of 15 to 240 minutes, preferably 30 to 180 minutes, more preferably 45 to 120 minutes, most preferably 60 to 90 minutes.

[0032] Preferably, in the first step, a titanium catalyst in the form of a sol is added to the compound containing at least one hydroxyl group, then 0.1% to 7% by weight of a water capturing agent, preferably vinyltrimethoxysilane (VTMO), is added to the resulting mixture, and then the compound containing at least two isocyanate groups is added.

[0033] Preferably, in the second step, the molar ratio of the functional groups of the isocyanate prepolymer to the silanising agent - aminoalkylsilane is in the range of 1.00:3.00 to 1.00:1.00, more preferably 1.00:2.50 to 1.00:1.50, even more preferably 1.00:2.25 to 1.0:1.75, most preferably 1.00:2.10 to 1.00:1.90, wherein the silanising agent - aminoalkylsilane is selected from the group including: N-(n- butyl)-aminopropyltrimethoxysilane, N- phenylaminomethyldimethoxymethylsilane, aminopropyltriethoxysilane, aminopropyltrimethoxy silane, aminobutyltriethoxy silane, N - (2- aminoethyl- 3 - aminopropyl)triethoxysilane, aminoundecyltrimethoxysilane, aminopropylmethyldiethoxysilane, phenylaminopropyltrimethoxysilane, methylaminopropyltrimethoxysilane, n-butylaminopropyltrimethoxysilane, t- butylaminopropyltrimethoxysilane, cyclohexylaminopropyltrimethoxysilane, dibutyl maleate aminopropyltrimethoxysilane, dibutyl-maleate substituted 4- amino-3,3-dimethylbutyltrimethoxysilane, aminopropyltrimethoxysilane, and mixtures thereof, N-methyl-3-amino-2-methylpropyltrimethoxysilane, N-ethyl-3- amino-2-methylpropyltrimethoxysilane, N-ethyl-3-amino-2- methylpropyldiethoxysilane, N-ethyl-3-amino-2-methylpropyltriethoxysilane, N- ethyl-3-amino-2-methylpropylmethyldimethoxysilane, N-butyl-3-amino-2- methylpropyltrimethoxysilane, 3-(N-methyl-3-amino-l-methyl-l- ethoxy)propyltrimethoxysilane, N-ethyl-4-amino -3,3- dimethylbutyldimethoxymethylsilane, N-ethyl-4-amino-3,3- dimethylbutyltrimethoxysilane, bis-(3-trimethoxysilyl-2-methylpropyl)amine, N- (3'-trimethoxysilylpropyl)-3-amino-2-methylpropyltrimethoxysilane, N,N-bis[(3- triethoxysilyl)propyl] amine, N,N-bis[(3-tripropoxysilyl)propyl]amine, N-(3- trimethoxysilyl)propyl-3-[N-(3-trimethoxysilyl) )-propylamino]propionamide, N- (3-triethoxysilyl)propyl-3-[N-3-triethoxysilyl]propylamino]propionamide, N-(3- trimethoxysilyl)propyl-3-[N-3-triethoxysilyl]propylamino] propionamide, 3- trimethoxysilylpropyl-3-[N-(3-trimethoxysilyl)propylamino]-2-methylpropionate, methyl 3 -triethoxy silylpropyl-3-[N-(3 -triethoxy silyl)propylamino]-2-propionate, 3-[N-(3-triethoxysilyl)propylamino]-2-methylpropionate, gammamercaptopropyltrimethoxysilane and N,N'-bis((3-trimethoxysilyl)propyl)amine.

[0034] Preferably, the mixture prepared in the second step is stirred at a constant temperature in the range of 15 to 120°C, preferably 20 to 100°C, more preferably 25 to 60°C, for a period of 15 to 240 minutes, preferably 30 to 180 minutes, more preferably 45 to 120 minutes, most preferably 60 to 90 minutes.

[0035] A second aspect of the invention is a silanised polyurethane prepolymer prepared with the above method, exhibiting a dynamic viscosity at a temperature of 25°C in the range of 7000 - 42000 mPa- s.

[0036] A third aspect of the invention is the use of a silanised polyurethane prepolymer prepared with the above method to produce an adhesive, sealant, composite, coating. In a further aspect, the invention relates to a method for producing a moisture-cured one-component silanised foam, including mixing of: a) the silanised polyurethane prepolymer, b) a diluent in an amount of 1.0 to 30.0 % by weight; c) at least one curing reaction catalyst in an amount of 0.01 to 5.0 % by weight; d) at least one surfactant in an amount of 0.1-10.0 % by weight; e) injecting of at least one propellant in an amount of 5 to 35% by weight;

[0037] Preferably, the diluent is selected from the group of organophosphorus compounds including tris(2-chloro- 1 -methylethyl phosphate, tert-butylphenyldiphenyl phosphate, tert-butyltriaryl phosphate, N,N-bis-(2- hydroxyethyljaminomethanephosphonic acid diethyl ester, tris(ethyl) phosphate, tris(2-chloroethyl) phosphate, tris[2-chloro-l-(chloromethyl)ethyl] phosphate, chlorinated paraffins.

[0038] Preferably the surfactant is selected from the group of compounds belonging to the group of organosilicone compounds, more preferably to the group of polydimethylsiloxanes modified with alkylene polyoxides, most preferably polydimethylsiloxanes modified with alkylene polyoxides intended to be used as a stabiliser for one-component polyurethane foam.

[0039] Preferably, the propellant is in a condensed state at a temperature of 25°C at a pressure in the range of 0.1 to 1.8 MPa, preferably 0.15 to 1.5 MPa, more preferably 0.15 to 1.0 MPa, and is a compound selected from the group comprising short hydrocarbons, including: propane, n-butane, isobutane, n-pentane, isopentane, cyclopentane, freons, including: dichlorodifluoromethane, 1, 1,1,2- tetrafluoroethane, difluoroethane, 2,3,3,3-tetrafluoropropene and / or ethers, including diethyl ether. In a further aspect, the object of the invention is a one-component moisture-cured silanised foam, prepared by the above method released from an aerosol container using a gun applicator, having a dust-free time at a temperature of 23 °C and a relative humidity of 50% in the range of 2 to 30 minutes, preferably in the range of 7 to 9 minutes, tested according to the FEICA OCF TM 1014:2013 method; a cutting time at a temperature of 23 °C and a relative humidity of 50% in the range of 10 to 120 minutes, preferably in the range of 35-44 minutes, tested according to the FEICA OCF TM 1005:2013 method; an in-box capacity at a temperature of 22°C and a relative humidity of 20% when using a foam of 750 g net weight in the range of 10 to 60 dm3, preferably in the range of 18 to 26 dm3, tested according to the FEICA OCF TM 1003:2013 method; a post-expansion at a temperature of 23°C and a relative humidity of 20%, using a slotted mould sprayed with 10 g of water before application, below 20%, tested according to the FEICA OCF TM 1010:2016 method.

[0040] In a further aspect, an object of the invention is a moisture-cured polyurethane polymer prepared from a silanised foam having a shrinkage at a temperature of 22°C and a relative humidity of 20% in moist conditions below 5% and in dry conditions below 3%, tested according to the FEICA OCF TM 1004:2013 method; a compressive strength at 22°C and a relative humidity of 20% in the range of 4 to 40 kPa, preferably 15.5 to 17.5 kPa, tested according to the FEICA OCF TM 1011:2013 method.

[0041] Detailed description of the invention

[0042] Selective catalyst in the form of a sol comprising, in its structure, titanium with a covalently bound OH

[0043] =Ti-OH group and a =Ti-O-Ti residue, can be used to lower the activation energy of the reaction of a polyol or prepolymer terminated with OH groups with an isocyanate or prepolymer terminated with NCO groups, preferably containing NCO groups non-equivalent in terms of reactivity. The use of this type of catalyst allows preparing a silanised polyurethane prepolymer with a relatively low viscosity and, therefore, low content of higher oligomers, and ultimately a one-component foam not containing, in its composition, organotin compounds (produced by the catalysts usually used) and free NCO groups and monomeric isocyanates.

[0044] Method for preparing a titanium catalyst

[0045] Examples of the use of a selective catalyst for the reaction of an asymmetric isocyanate with a polyol in the synthesis of NCO prepolymers can be found in the state of the art. However, they do not include the sol of a titanium compound containing OH groups, prepared in the process of hydrolysis and partial condensation, preferably, of titanium alcoholate in an alcohol solution.

[0046] For this purpose, a titanium-containing organic compound is dropped into the prepared amount of protic solvent, while stirring continuously, in order to achieve the intended concentration. In order to carry out the step of acidification and simultaneous hydrolysis, an acid is dropped into the previously prepared solution.

[0047] As a result, a mixture of chemical compounds is formed that has a general structure of the type:

[0048] Ti(OH)4, and / or Ti2O2(OH)4 - produced as a result of polycondensation (titanium sol), and (TiO2)n when polycondensation continues (titanium gel), where n is in the range of 4 to co.

[0049] Suitable protic solvents, according to the invention shown, are all alcohols containing 1 to 8 carbon atoms in their structure. It is preferable when they contain 2 to 6 carbon atoms, even more preferable when they contain 2 to 4, most preferably 3. Examples of such solvents include: methanol, ethanol, propan-2-ol, butan-l-ol, butan-2-ol, 2-methyIpropan-2-ol, pentan- 1 -ol, 3 -methy Ibutan- 1 -ol, 2-methyIbutan- l -ol ol, 2,2-dimethylpropan-l-ol, pentan-3-ol, pentan-2-ol, 3-methylbutan-2-ol, 2- methylbutan-2-ol, hexan-l-ol, hexan-2-ol ol, hexan-3-ol, 2-ethyl-l -hexanol, heptan-l-ol, heptan-2-ol, heptan-4-ol, octan-l-ol, octan-2-ol. According to the present invention, a solution of titanium-containing organic compound is prepared. It is preferable that the concentration of the titanium- containing organic compound in the protic solvent is between 1 and 30% by weight, more preferably between 2 and 25% by weight, even more preferably between 3 and 20% by weight, most preferably between 5 and 15% by weight. For this purpose, the titanium-containing organic compound is dropped into the prepared amount of protic solvent, while stirring continuously, in order to achieve the intended concentration.

[0050] In order to carry out the step of acidification and simultaneous hydrolysis, an acid is dropped into the previously prepared solution. It is preferable that the concentration of the inorganic acid, in relation to the concentration of protons, is between 0.01 mol / dm3, up to a maximum concentration for the selected pure acid, more preferably between 0.03 and 1.00mol / dm3, even more preferably between 0.05 and 0.5 mol / dm3, most preferably between 0.07 and 0.20 mol / dm3. It is preferable that the acid solution used is prepared on the same protic solvent that was used to dilute the titanium-containing organic compound. It is preferable that the amount of acid dosed into the pre -prepared solution of the titanium-containing organic compound is between 1 mg and 10 g , more preferably between 3 and 1 g , even more preferably between 5 and 100 mg, and most preferably between 10 and 20 mg (per 100 g of solution). In doing so, the general rule is that the more concentrated the acid, the less of it should be added. It is preferable to carry out the acid dropping with constant stirring, for example, using a magnetic stirrer.

[0051] Method for preparing NCO prepolymer

[0052] The dynamic viscosity of the silanised polyurethane prepolymer is mainly influenced by the viscosity of the polyurethane NCO prepolymer prepared in the first step of the process. It is preferable to carry out the reaction of a poly ether diol with a diisocyanate at a lowered temperature in order to reduce the dynamic viscosity of the silanised polyurethane prepolymer. Lowering the temperature of the urethane reaction, catalysed by a selective catalyst, results in a preference for the most active functional groups of the reactants. In particular, the use of diisocyanates with an asymmetric distribution of NCO groups allows a prepolymer with a reduced viscosity to be prepared, due to a reduction in the kinetics of side reactions leading to the formation of dimers, biurets or allophonates, which in particular contribute to an increase in the degree of polydispersity of the prepolymer and, consequently, an increase in the dynamic viscosity of the prepolymer.

[0053] The silanised prepolymer according to the present invention is prepared in a two- step process. In the first step, a reaction of a compound or a group of several compounds containing free OH hydroxyl groups with another compound or group of compounds containing free NCO isocyanate groups in their structure is carried out. The titanium catalyst described above is used in the first step.

[0054] As the compound containing free OH hydroxyl groups, it is preferable to use one or a group of polyether or polyester polyols, or polyurethane prepolymers terminated with a hydroxyl group.

[0055] A polyol can also be produced from a reaction mixture containing one or more chain extenders and / or one or more other polyols. Examples of suitable chain extenders are polyhydric alcohols such as ethylene glycol, monopropylene glycol, propane - 1,3-diol, butane- 1,4-diol, hexane- 1,6-diol, diethylene glycol, triethylene glycol, tetraethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol and the like.

[0056] Additional polyols may be selected from the polyols described above and include polyether polyols, polyester polyols, polyetherester polyols, polyesterether polyols, polybutadienediols, polyoxyalkylene diols, polyoxyalkylene triols, poly tetramethylene glycols, polycaprolactone diols and triols and the like, all of which have at least one hydroxyl group.

[0057] It is also preferable if a given compound has a functionality of 2, i.e. 2 moles of hydroxyl groups are contained in one mole of the compound molecule. This means that polyols of the diol type are preferred. Polyols resulting from propoxylation are preferred for the process, i.e. in the production process, a starter in the form of propylene glycol or polypropylene glycol and / or water was submitted to the polyaddition reaction and the oxyalkylating agent was propylene oxide. Polyols produced in a process involving a double metal cyanide (DMC) catalyst are particularly suitable according to the present invention. These types of polyols are characterised by low levels of unsaturation and it is possible to achieve relatively high molecular weights and a relatively low polydispersity.

[0058] According to the present invention, it is preferable that the diol used has a molecular weight MW of 200 to 25000 g / mol, even more preferable that its MW is in the range of 300 to 12000 g / mol.

[0059] It is preferable if the polyol has an unsaturation level below 0.20 meq / g, more preferably below 0.15 meq / g, even more preferably below 0.10 meq / g, most preferably below 0.05 meq / g.

[0060] It is preferable if the water content in the polyol is below 0.15% (m / m), more preferably below 0.10% (m / m), even more preferably below 0.07% (m / m), most preferably below 0.05% (m / m).

[0061] Examples of polyether polyols available in the industry are those produced, for example, by COVESTRO, DOW, HUNTSMAN, OLTCHIM, PCC ROKITA, REPSOL, SHELL, etc. available under trade names such as Arcol, Desmofen, Voranol, Vorapel, Jeffol, Petol, Rokopol, Repsol, Caradol.

[0062] A group of particularly useful isocyanates includes the traditionally used organic isocyanates, especially organic diisocyanates from which polyurethane polymers are usually made.

[0063] Examples of isocyanates available in the industry are those produced, for example, by BAYER, BASF, BORSODCHEM, DOW, HUNTSMAN, KUMHO, WANHUA, etc. available under trade names such as Desmodur, Lupranate, Ongronate, Suprasec, Voranate, Cosmonate, Wannate.

[0064] Preferably, according to the present invention, in the first step of the prepolymer synthesis, a titanium catalyst solution in the form of a sol, with a concentration in the range of 0.001% to 5.00%, preferably 0.01% to 1.0%, more preferably 0.02% to 0.5% relative to a polyol containing at least one hydroxyl group, is used. According to the present invention, it is preferable if the concentration of the prepared titanium catalyst used in the process is dependent on the weight of the polyol used and should be proportional to the MW of the polyol used. Based on the above, when using a diol with an MW of 400 g / mol, the concentration of the prepared titanium catalyst should be between 200 and 2000 ppm, more preferably it should be between 500 and 1500 ppm, even more preferably it should be between 750 and 1250 ppm. Accordingly, when using a diol with an MW of 12000 g / mol, the concentration of the prepared titanium catalyst should be between 1000 and 5000 ppm, more preferably it should be between 1500 and 4000 ppm, even more preferably it should be between 2000 and 4000 ppm, most preferably it should be between 2500 and 3500 ppm.

[0065] It is preferable, according to the present invention, if the polyol loaded into the reactor with a suitable amount of titanium catalyst can be dried under vacuum, in order to further lower the water content and remove the solvent from the catalyst, as well as to avoid contact of the reaction mixture component with moisture in the air. It is preferable when the pressure in the reactor during drying of the polyol is below 200 mbar, even more preferable when it is below 100 mbar, most preferably when it is below 50 mbar. The drying time depends on the water content of the polyol used. It is preferable when the drying lasts between 30 and 180 min, even more preferable when it lasts between 45 and 150 min, most preferably when it lasts between 60 and 120 min. The drying can be assisted by the flow of an inert gas stream for the process, e.g.: nitrogen.

[0066] It is preferable, according to the present invention, when the temperature of the reaction between the polyol used and the isocyanate is as constant as possible and is in the range of 15-120°C, more preferably when this temperature is in the range of 20-100°C; most preferably when it is in the range of 25-60°C. According to the present invention, it is preferable when the temperature at which the prepolymerisation process is carried out, is dependent on the weight of the polyol used and should be proportional to the MW of the polyol used. Based on the above, when using a diol with an MW of 400 g / mol, the process temperature should be between 15 and 60°C, more preferably between 15 and 50°C, even more preferably between 15 and 40°C, most preferably in the range of 15-30°C. Accordingly, when using a diol with an MW of 12000 g / mol, the concentration of the prepared titanium catalyst should be between 15 and 120°C, more preferably it should be between 30 and 100°C, even more preferably it should be between 45 and 90°C, most preferably it should be in the range of 60-80°C.

[0067] It is preferable when the prepolymerisation process is carried out in a nitrogen atmosphere under normal pressure.

[0068] The reaction between the polyol and the isocyanate is carried out by controlling the amount of free NCO groups until the theoretical calculated content of free NCO groups in the prepolymer is reached. The measurement can be carried out by reverse titration of the excess dibutylamine, used to saturate the free NCO groups, with 0.1 M hydrochloric acid. It is also possible to use a measurement method using FTIR spectroscopy including the band that is characteristic of the N=C bond (WN-1600 cm-1).

[0069] Method for silanising NCO prepolymer

[0070] Once the intended concentration of free NCO groups has been reached, the second step - silanisation - should be carried out without delay.

[0071] It is preferable, according to the present invention, when the temperature of the reaction between the isocyanate prepolymer and the aminosilane, is as constant as possible and is in the range of 15-120°C, more preferably when this temperature is in the range of 20-100°C, most preferably when it is in the range of 25-60°C.

[0072] It is preferable when the silanisation process is carried out in a nitrogen atmosphere under normal pressure. However, other solutions known from the state of the art may be used.

[0073] The silanisation process is carried out by controlling the amount of free NCO groups until the theoretical calculated content of free NCO groups in the prepolymer is reached. Conventionally, it is assumed that the ratio of reactants is such that all free NCO groups of the isocyanate prepolymer are bound to the silanising agent / aminosilane. The measurement can be carried out by reverse titration of the excess dibutylamine, used to saturate the free NCO groups, with 0.1 M hydrochloric acid. It is also possible to use a measurement method using FTIR spectroscopy including the band that is characteristic of the N=C bond (WN-1600 cm-1).

[0074] Method for preparing a one-component silanised foam composition

[0075] The one-component polyurethane foam is usually prepared as follows. In a mixer properly adapted to the viscosity of the raw materials, the ingredients of component A are homogenised. In the case of polyurethanes, the so-called polyol blend containing the appropriate polyol together with additives such as catalysts, stabilisers etc. is taken as component A. The blender so prepared is dosed into an aerosol container and then ingredient B is added. Ingredient B is an isocyanate, usually polymeric MDI. A valve is then fitted and propellant gases are injected through it using appropriate instrumentation.

[0076] An appropriate amount of diluent is added to the silanised prepolymer prepared according to the above invention in order to be able to control the viscosity of the mixture. It is preferable when the diluent used has properties that make the cured foam flame-retardant and / or plasticised. The amount of diluent depends on the final viscosity of the mixture to be prepared. It is preferable according to the present invention that the viscosity of the mixture is in the range of 1000 to 50000 mPa s, more preferably in the range of 5000 to 40000 mPa s, even more preferably in the range of 10000 to 30000 mPa s, most preferably in the range of 15000 to 25000 mPa- s. It is preferable that the amount of diluent present in the composition mixture according to the present invention is in the range of 1.0 to 30.0 parts by weight, still more preferably 3.0 to 25.0 parts by weight, most preferably 7.0 to 20.0 parts by weight.

[0077] The silanised prepolymer composition according to the present invention will preferably also include the addition of at least one surfactant in order to ensure the durability of the cellular structure of the foam during the processes of application, cross-linking and possible subsequent expansion of propellant gases. Surfactants assist in controlling the ratio of open cells to closed cells, which in turn ensures dimensional stability and affects the pressure at which the foam cures. Examples of commercially available organosilicone surfactants suitable for use in the present invention include those typically used in applications associated with typical polyurethane foams. Such compounds are offered by Momentive, Evonik, Schill & Seilacher, BYK Chemie etc.

[0078] It is preferable that the amount of surfactants present in the composition mixture according to the present invention is in the range of 0.1 to 10.0 parts by weight, still more preferably 0.5 to 8.0 parts by weight, most preferably 1.0 to 6.0 parts by weight.

[0079] The silanised prepolymer composition according to the present invention will preferably also include the addition of at least one catalyst for the cross-linking reaction in order to ensure the durability of the cellular structure and to accelerate the processing time.

[0080] The moisture-curing reaction for prepolymers terminated with silane groups can be catalysed by an acid, a base or a metal. Suitable catalysts include, e.g., organometallic compounds containing tin, iron, zinc, bismuth, titanium, amines, amide esters, etc. Often, the phenomenon of synergy is observed when using two or more types of cross-linking catalysts. There is sometimes no need to add an additional catalyst, as the one used during synthesis also catalyses the curing reaction of the prepolymer in contact with moisture in the air.

[0081] It is preferable that the total amount of curing catalyst(s) present in the composition mixture according to the present invention is in the range of 0.01 to 5.00 parts by weight, still more preferably 0.1 to 3.0 parts by weight, most preferably 0.5 to 2.0 parts by weight.

[0082] A suitable foaming agent or mixture of foaming agents, usually called a propellant, is necessary to foam the formulation and to dose it. According to the present invention, it is preferable when this substance or mixture of different substances is a gas. It is preferable that the amount of propellants present in the composition mixture according to the present invention is in the range of 8.0 to 35.0 parts by weight, still more preferably 12.0 to 30.0 parts by weight, most preferably 15.0 to 25.0 parts by weight.

[0083] The presented method for preparing silane one-component foam is further characterised by a number of advantages. For a person familiar with the production of traditional one-component foams, an important difference, which is also an advantage, is that there is no reaction between ingredients A and B inside the pressure container. This translates into an increased level of safety in the production process. Since there is no exothermic effect in the chemical reaction, there is no risk of an uncontrolled build-up of pressure inside the foam container and its consequent leakage or explosion. Another advantage of this invention is that the finished product - a silanised one-component foam - is prepared as soon as the ingredients are completely mixed. Referring to the curing reaction chemistry itself of the one- component silanised foam, the cross-linking reaction proceeds without any release of carbon dioxide - as would be the case with the standard solution. In turn, a small amount of methanol, which has a much lower vapour pressure than carbon dioxide, is released. For this reason, there is either no or very limited secondary increase in volume due to gas expansion.

[0084] Examples of embodiments of the invention

[0085] Example 1

[0086] Preparation of a titanium catalyst

[0087] 10 g of tetra-isopropyl titanate was dissolved in 100 g of isopropanol, under conditions of ambient temperature. The whole was then acidified by adding 0.1 g of 0.1 M hydrochloric acid with continuous stirring for 1 hour and conditioned in a sealed glass container at room temperature and atmospheric pressure for 24 hours.

[0088] The urethane reaction catalyst prepared according to the above procedure was tested by FTIR spectrometry in order to identify the composition. Infrared (IR) spectra were measured on a Nicolet™ iS50 FTIR spectrometer using an ATR (Attenuated Total Reflectance) attachment in the range of 4000-400 cm1with a resolution of 2 cm-1.

[0089] The spectrum of the hydrolysed catalyst contains solvent- specific bands and Ti-0 vibration- specific bands, with bands at 618, 682 and 1016 cm1being particularly noticeable. The bands for the isopropylate ion that coordinates the Ti4+ions are located at similar wavenumbers to those in the pure solvent. This means that the interaction between Ti and the solvent ions does not significantly affect the lengths and geometry of the bonds in the alcohol molecule. The bands in the range of 700- 400 cm1correspond to Ti-O-Ti vibrations and therefore originate from the formed titanium oxides, while the bands in the higher range (1200-700 cm1) originate from Ti-OR vibrations, i.e. from the titanium ion coordinated to the alcoholate.

[0090] Wavenumber (cm'1)

[0091] Fig. 1 shows the spectra of: the pure solvent - isopropyl alcohol (iPrOH) and the catalyst dissolved in isopropyl alcohol after acidification (hydrolysis) with HC1 ((iPrO)4Ti - iPrOH);

[0092] Wavenumber (cm'1)

[0093] Fig. 2 shows details of the spectra in the frequency range of 1700-400 cm1.

[0094] Example 2

[0095] Preparation of silanised prepolymer

[0096] A prepolymer terminated with free NCO groups is formed as a result of the reaction of a selected diol-type polyol and a selected diisocyanate in the ratio of 10:19.5 [mokmol]. A catalyst is added to the polyol in an amount depending on the weight of the polyol used and the type of catalyst such that for a diol with an MW of 400 g / mol the concentration of the titanium catalyst should be between 200 and 2000 ppm, more preferably it should be between 500 and 1500 ppm while for a diol with an MW of 12000 g / mol the concentration of the titanium catalyst should be between 1000 and 5000 ppm, more preferably it should be between 1500 and 4000 ppm, still more preferably it should be between 2000 and 4000 ppm, most preferably it should be between 2500 and 3500 ppm. The whole was heated to approx. 60°C and stirred under vacuum for 60 min. An appropriate amount of VTMO (vinyltrimethoxysilane) was then added under a nitrogen atmosphere. This represented 5% by weight of the prepared mixture of polyol, catalyst and VTMO. After 5 min, the selected diisocyanate was added gradually (over 10 min). The reaction with the diisocyanate was carried out until the previously calculated theoretical content of free NCO groups in the prepared prepolymer was reached, assuming that all the diisocyanate used would form bonds with the polyol. Then, while maintaining a constant temperature, usually 60°C, a pre-calculated amount of Dynasylan 1189 was gradually added, assuming a reactant ratio of NCO prepolymer : silanising agent of 10:20.5 [mokmol]. The process was carried out until the free NCO group content was below 0.1 % and then VTMO was added again so that it represented 2 % by weight of the prepared silanised prepolymer.

[0097] A lowered-temperature test for the reaction of the polyol with the isocyanate was also carried out for Rokopol D450 and 2,4-toluene diisocyanate TDI. The dried polyol together with the titanium catalyst, being an object of this invention, was cooled down to 5°C before the addition of VTMO and isocyanate. Following the reaction with TDI (the temperature during the reaction was increased to 40°C), in accordance with the previously made assumptions regarding the degree of conversion, the reaction with the silanising agent Dynasylan 1189 was carried out at a temperature of 60°C and the dynamic viscosity was measured.

[0098] Table 1 shows examples of silanised prepolymers together with the resulting dynamic viscosity.

[0099] Example 3

[0100] Description of the preparation of one-component silanised foam

[0101] An appropriate amount of Roflam P (TCPP), which represented 12% by weight of the mixture formed at this point, was added to the prepared silanised prepolymer. Then, an appropriate amount of a foam structure-stabilising surfactant (an organosilicone compound), which represented 4% by weight of the mixture formed at this point, was added. Then, an appropriate amount of diazobicycloundecene and dimorpholinodiethyl ether catalysts in a 2: 1 ratio, which represented 1.2 per cent by weight of the mixture formed at this point, was added. The whole thing was then mixed. After mixing, the mixture was transferred to a pressure container intended 1 for one-component foam application and was closed with a suitable aerosol valve. Then, an appropriate amount of propellants (propane, isobutane, dimethyl ether), which represented 20% of the weight of the mixture prepared at that point, was injected. The whole was mixed using a one-component foam shaker for thorough mixing. Table 2 shows examples of one-component silanised foams produced with the use of the appropriate silanised prepolymer (the numbering is as shown in Table 1) and the tendency of the resulting foam to collapse.

[0102] Table 3 includes examples of foams that do not tend to collapse, together with the measured application parameters. Application parameters were tested according to industry-accepted measurement methods proposed by the Association of the European Adhesive & Sealant Industry FEICA.

[0103] Table 1.

[0104] Table 2.

[0105] Table 3.

[0106] The silanised prepolymer according to the invention can be used as an ingredient to make an adhesive, sealant, composite or coatings. The one-component foam containing the silanised prepolymer, due to its ease of use and efficiency, can be widely used in the construction industry, e.g. as a filler material for the installation of windows or doors in buildings, a filler material for voids or openings in walls for the installation of e.g. communal utilities.

Claims

AMENDED CLAIMS received by the International Bureau on 09 February 2024 (09.02.2024)1. A method for preparing a silanised polyurethane prepolymer, comprising a process wherein: a) in a first step, an isocyanate prepolymer is prepared by contacting:- compounds containing at least one hydroxyl group selected from the group consisting of: poly(oxy)alkylenated diols (so-called polyether diols), poly(oxyethylene) ether diols, poly(oxypropylene) ether diols, poly(oxyethylene-oxypropylene) ether diols, poly(oxyalkylene) ether triols (e.g. polyether triols), poly(oxyethylene) ether triols, poly(oxypropylene) ether triols, poly(oxyethylene-oxypropylene) ether triols, polybutadiene diols, with- compounds containing at least two isocyanate groups,- in the presence of a titanium catalyst in the form of a sol, wherein the titanium catalyst is prepared by a method comprising the following steps: al) preparing a solution of a titanium alcoholate compound in a protic solvent, preferably with a concentration of 1-30% by weight, a2) acidifying the solution prepared in step (al) with an acid, preferably the amount of acid dosed into the solution of the titanium-containing organic compound per 100 g of solution being in the range of 1 mg to 10 g, preferably from 1 mg to 100 mg, wherein the general structure of titanium catalyst is Ti(OH)4, and / or Ti2O2(OH)4 formed as a result of polycondensation and (TiO2)n when polycondensation proceeds further (titanium gel), where n ranges from 4 to co. b) in a second step, a silanising agent is added to the isocyanate prepolymer prepared in the first step.

2. The method for preparing a silanised polyurethane prepolymer according to claim 1, characterised in that the titanium alcoholate is selected from the group including: tetraethyl titanate, di-iso-butoxytitanium chelate (ethyl acetoacetate titanate), tetra-iso- propyl titanate, tetra-n-butyl titanate, tetra-2-ethylhexyl titanate, titanium acetylacetonate, polybutyl titanate, triethanolamine titanate, aqueous titanium chelate, ethyl tetratitanate, tetra-iso-propyl titanate, tetra-n-butyl titanate, preferably tetra-iso- propyl titanate, tetra-n-butyl titanate or tetra-iso-propyl tetratitanate.36AMENDED SHEET (ARTICLE 19)3. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 or 2, characterised in that the protic solvent is selected from the group including: methanol, ethanol, propan-2-ol, butan-l-ol, butan-2-ol, 2-methylpropan-2-ol, pentan- 1- ol, 3-methylbutan-l-ol, 2-methylbutan-l-ol ol, 2,2-dimethylpropan-l-ol, pentan-3-ol, pentan-2-ol, 3-methylbutan-2-ol, 2-methylbutan-2-ol, hexan-l-ol, hexan-2-ol ol, hexan- 3-ol, 2-ethyl-l -hexanol, heptan-l-ol, heptan-2-ol, heptan-4-ol, octan-l-ol, octan-2-ol.

4. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 3, characterised in that the acid is selected from the group including: boric acid H3BO3, carbonic acid H2CO3, nitrous (nitric(III) acid) HNO2, nitric (V) acid HNO3, phosphonic (phosphorus(III)) acid H3PO3, phosphoric (V) acid H3PO4, sulphurous (sulphuric(IV)) acid H2SO3, sulphuric (sulphuric(VI)) acid H2SO4, chloric (I) acid HC10, chloric (III) acid HCIO2, chloric (V) acid HCIO3, chloric (VII) acid HCIO4, hydrocyanic acid HCNaq, hydrosulphuric acid EhSaq, hydrofluoric acid HFaq, hydrochloric acid HClaq, hydrobromic acid HBraq, hydroiodic acid HIaq, formic acid HCOOH, acetic acid CH3COOH, citric acid HOOC-CH2-C(OH)(COOH)-CH2-COOH, lactic acid CH3CH(OH)COOH.

5. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 4, characterised in that in the first step, the titanium catalyst solution in the form of a sol, with a concentration in the range of 0.01% to 5.00% relative to a compound containing at least one hydroxyl group, is used.

6. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 5, characterised in that in the first step, the molar ratio of the compound containing at least two isocyanate groups to compounds containing at least one hydroxyl group is in the range of 3.00:1.00 to 1.00:1.00, even more preferably 2.50:1:00 to 1.50:1.00, even more preferably 2.25:1.00 to 1.75:1.00, most preferably 2.10:1.00 to 1.90:1.00.

7. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 6, characterised in that the compound containing at least two isocyanate groups is selected from the group including: isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'- diphenylmethane diisocyanate, dicyclohexylmethane-4,4' diisocyanate, hexamethylene diisocyanate, bis-(4-isocyanatocyclohexyl)methane and a mixture of 2,4- and 4,4'- diphenylmethane diisocyanates.37AMENDED SHEET (ARTICLE 19)8. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 7, characterised in that the mixture prepared in the first step is stirred at a constant temperature in the range of 15 to 120°C, preferably 20 to 100°C, more preferably 25 to 60°C, for a period of 15 to 240 minutes, preferably 30 to 180 minutes, more preferably 45 to 120 minutes, most preferably 60 to 90 minutes.

9. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 8, characterised in that, in the first step, the titanium catalyst in the form of a sol is added to the compound containing at least one hydroxyl group, then 0.1% to 7% by weight of a water capturing agent, preferably vinyltrimethoxysilane, is added to the resulting mixture, and then the compound containing at least two isocyanate groups is added.

10. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 9, characterised in that, in the second step, the molar ratio of the functional groups of the isocyanate prepolymer to the silanising agent - aminoalkylsilane is in the range of 1.00:3.00 to 1.00:1.00, more preferably 1.00:2.50 to 1.00:1.50, even more preferably 1.00:2.25 to 1.0:1.75, most preferably 1.00:2.10 to 1.00:1.90, wherein the silanising agent - aminoalkylsilane is selected from the group including: N-(n-butyl)- aminopropyltrimethoxysilane, N-phenylaminomethyldimethoxymethylsilane, aminopropyltriethoxysilane, aminopropyltrimetho xysilane, aminobutyltriethoxysilane, N-(2-aminoethyl-3-aminopropyl)triethoxysilane, aminoundecyltrimethoxysilane, aminopropylmethyldiethoxysilane, phenylaminopropyltrimethoxysilane, methylaminopropyltrimethoxysilane, n-butylaminopropyltrimethoxysilane, t- butylaminopropyltrimethoxysilane, cyclohexylaminopropyltrimethoxysilane, dibutyl maleate aminopropyltrimethoxysilane, dibutyl-maleate substituted 4-amino-3,3- dimethylbutyltrimethoxysilane, aminopropyltrimethoxy silane, and mixtures thereof, N- methyl-3-amino-2-methylpropyltrimethoxysilane, N-ethyl-3-amino-2- methylpropyltrimethoxysilane, N-ethyl-3-amino-2-methylpropyldiethoxysilane, N- ethyl-3-amino-2-methylpropyltriethoxysilane, N-ethyl-3-amino-2- methylpropylmethyldimethoxysilane, N-butyl-3-amino-2- methylpropyltrimethoxysilane, 3-(N-methyl-3-amino-l-methyl-l- ethoxy)propyltrimethoxysilane, N-ethyl-4-amino -3,3- dimethylbutyldimethoxymethylsilane, N-ethyl-4-amino-3,3- dimethylbutyltrimethoxysilane, bis-(3-trimethoxysilyl-2-methylpropyl)amine, N-(3 trimethoxysilylpropyl)-3-amino-2-methylpropyltrimethoxysilane, N,N-bis[(3-38AMENDED SHEET (ARTICLE 19)triethoxy silyljpropyl] amine, N,N-bis[(3-tripropoxysilyl)propyl]amine, N-(3- trimethoxysilyl)propyl-3-[N-(3-trimethoxysilyl) )-propylamino]propionamide, N-(3- triethoxysilyl)propyl-3-[N-3-triethoxysilyl]propylamino]propionamide, N-(3- trimethoxysilyl)propyl-3-[N-3-triethoxysilyl]propylamino] propionamide, 3- trimethoxysilylpropyl-3-[N-(3-trimethoxysilyl)propylamino]-2-methylpropionate, methyl 3 -triethoxy silylpropyl-3 - [N-(3 -triethoxy silyl)propylamino] -2-propionate, 3 - [N- (3-triethoxysilyl)propylamino]-2-methylpropionate, gammamercaptopropyltrimethoxysilane and N,N'-bis((3-trimethoxysilyl)propyl)amine.

11. The method for preparing a silanised polyurethane prepolymer according to any one of claims 1 - 10, characterised in that the mixture prepared in the second step is stirred at a constant temperature in the range of 15 to 120°C, preferably 20 to 100°C, more preferably 25 to 60°C, for a period of 15 to 240 minutes, preferably 30 to 180 minutes, more preferably 45 to 120 minutes, most preferably 60 to 90 minutes.

12. A silanised polyurethane prepolymer prepared with the method according to any one of claims 1 - 11, exhibiting a dynamic viscosity at a temperature of 25°C in the range of 7000 - 42000 mPa s.

13. A use of a silanised polyurethane prepolymer, prepared with the method according to any one of claims 1 - 12, to produce an adhesive, sealant, composite, coating.

14. A method for producing a moisture-cured one-component silanised foam, including mixing of: a) the silanised polyurethane prepolymer prepared with the method according to any one of claims 1 - 13, b) a diluent in an amount of 1.0 to 30.0 % by weight; c) at least one curing reaction catalyst in an amount of 0.01 to 5.0 % by weight; d) at least one surfactant in an amount of 0.1-10.0 % by weight; e) injecting of at least one propellant in an amount of 5 to 35% by weight.

15. The method for producing a moisture-cured one-component silanised foam according to claim 14, characterised in that the diluent is selected from the group of organophosphorus compounds including tris(2-chloro- 1 -methylethyl phosphate, tert-butylphenyldiphenyl phosphate, tert-butyltriaryl phosphate, N,N-bis-(2- hydroxyethyljaminomethanephosphonic acid diethyl ester, tris(ethyl) phosphate, tris(2- chloroethyl) phosphate, tris[2-chloro-l-(chloromethyl)ethyl] phosphate, chlorinated paraffins.39AMENDED SHEET (ARTICLE 19)16. The method for producing a moisture-cured one-component silanised foam according to claim 14 or 15, characterised in that the surfactant is selected from the group of compounds belonging to the group of org ano silicone compounds, more preferably to the group of polydimethylsiloxanes modified with alkylene polyoxides, most preferably polydimethylsiloxanes modified with alkylene polyoxides intended to be used as a stabiliser for one-component polyurethane foam.

17. The method for producing a moisture-cured one-component silanised foam according to any of claims 14 to 16, characterised in that the propellant is in a condensed state at a temperature of 25°C at a pressure in the range of 0.1 to 1.8 MPa, preferably 0.15 to 1.5 MPa, more preferably 0.15 to 1.0 MPa, and is a compound selected from the group comprising short hydrocarbons, including: propane, n-butane, isobutane, n-pentane, isopentane, cyclopentane, freons, including: dichlorodifluoromethane, 1, 1,1,2- tetrafluoroethane, difluoroethane, 2,3,3,3-tetrafluoropropene and / or ethers, including diethyl ether.

18. A one-component moisture-cured silanised foam, prepared with the method according to any one of claims 14 - 17, released from an aerosol container using a gun applicator, having a dust-free time at a temperature of 23 °C and a relative humidity of 50% in the range of 2 to 30 minutes, tested according to the FEICA OCF TM 1014: 2013 method; a cutting time at a temperature of 23°C and a relative humidity of 50% in the range of 10 to 120 minutes, tested according to the FEICA OCF TM 1005: 2013 method; an in-box capacity at a temperature of 22°C and a relative humidity of 20% when using a foam of 750 g net weight in the range of 10 to 60 dm3, tested according to the FEICA OCF TM 1003: 2013 method; a post-expansion at a temperature of 23°C and a relative humidity of 20%, using a slotted mould sprayed with 10 g of water before application, below 20%, tested according to the FEICA OCF TM 1010: 2016 method.

19. The moisture-cured polyurethane polymer prepared from the silanised foam prepared with the method according to any one of claims 14 - 18, having a shrinkage at a temperature of 22°C and a relative humidity of 20% in moist conditions below 5% and in dry conditions below 3%, tested according to the FEICA OCF TM 1004: 2013 method; a compressive strength at 22°C and a relative humidity of 20% in the range of 4 to 40 kPa, tested according to the FEICA OCF TM 1011: 2013 method.AMENDED SHEET (ARTICLE 19)

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