EP2288635A1 - Adhésifs réactifs ayant une très faible teneur en diisocyanates monomères - Google Patents

Adhésifs réactifs ayant une très faible teneur en diisocyanates monomères

Info

Publication number
EP2288635A1
EP2288635A1 EP09753935A EP09753935A EP2288635A1 EP 2288635 A1 EP2288635 A1 EP 2288635A1 EP 09753935 A EP09753935 A EP 09753935A EP 09753935 A EP09753935 A EP 09753935A EP 2288635 A1 EP2288635 A1 EP 2288635A1
Authority
EP
European Patent Office
Prior art keywords
nco
polyurethane adhesive
component polyurethane
content
diisocyanate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP09753935A
Other languages
German (de)
English (en)
Inventor
Thomas Bachon
Bernhard Grünewälder
Birgit Ness
Kerstin Schröder
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Henkel AG and Co KGaA
Original Assignee
Henkel AG and Co KGaA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Henkel AG and Co KGaA filed Critical Henkel AG and Co KGaA
Publication of EP2288635A1 publication Critical patent/EP2288635A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/48—Polyethers
    • C08G18/4825—Polyethers containing two hydroxy groups
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/08—Processes
    • C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72—Polyisocyanates or polyisothiocyanates
    • C08G18/74—Polyisocyanates or polyisothiocyanates cyclic
    • C08G18/76—Polyisocyanates or polyisothiocyanates cyclic aromatic
    • C08G18/7614—Polyisocyanates or polyisothiocyanates cyclic aromatic containing only one aromatic ring
    • C08G18/7621—Polyisocyanates or polyisothiocyanates cyclic aromatic containing only one aromatic ring being toluene diisocyanate including isomer mixtures
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72—Polyisocyanates or polyisothiocyanates
    • C08G18/74—Polyisocyanates or polyisothiocyanates cyclic
    • C08G18/76—Polyisocyanates or polyisothiocyanates cyclic aromatic
    • C08G18/7657—Polyisocyanates or polyisothiocyanates cyclic aromatic containing two or more aromatic rings
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72—Polyisocyanates or polyisothiocyanates
    • C08G18/74—Polyisocyanates or polyisothiocyanates cyclic
    • C08G18/76—Polyisocyanates or polyisothiocyanates cyclic aromatic
    • C08G18/7657—Polyisocyanates or polyisothiocyanates cyclic aromatic containing two or more aromatic rings
    • C08G18/7664—Polyisocyanates or polyisothiocyanates cyclic aromatic containing two or more aromatic rings containing alkylene polyphenyl groups
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72—Polyisocyanates or polyisothiocyanates
    • C08G18/77—Polyisocyanates or polyisothiocyanates having heteroatoms in addition to the isocyanate or isothiocyanate nitrogen and oxygen or sulfur
    • C08G18/78—Nitrogen
    • C08G18/79—Nitrogen characterised by the polyisocyanates used, these having groups formed by oligomerisation of isocyanates or isothiocyanates
    • C08G18/791—Nitrogen characterised by the polyisocyanates used, these having groups formed by oligomerisation of isocyanates or isothiocyanates containing isocyanurate groups
    • C08G18/792—Nitrogen characterised by the polyisocyanates used, these having groups formed by oligomerisation of isocyanates or isothiocyanates containing isocyanurate groups formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J175/00—Adhesives based on polyureas or polyurethanes; Adhesives based on derivatives of such polymers
    • C09J175/04—Polyurethanes
    • C09J175/08—Polyurethanes from polyethers

Definitions

  • the present invention relates to reactive polyurethane compositions having a low content of monomeric diisocyanates, to a process for their preparation and to their use in reactive one-component adhesives / sealants, in particular for use as wood adhesives.
  • Reactive polyurethane adhesives and sealants in particular one-component moisture-curing systems, generally contain polymers which are liquid at room temperature and contain urethane groups, if appropriate urea groups, and reactive isocyanate groups.
  • Reactive polyurethane adhesives and sealants are characterized by a very high performance profile. Therefore, in recent years, new applications for these adhesives and sealants have become increasingly accessible. Compositions for such adhesives and / or sealants are already known from many patent applications and other publications.
  • these polyurethane compositions also have some systemic disadvantages.
  • One of the most serious disadvantages is the residual monomer content of isocyanates, in particular of the more volatile diisocyanates. These are of serious health concern and will in the future also lead to a mandatory labeling of products with R40 ("Limited evidence of a carcinogenic effect") .
  • WO96 / 006124 describes polyurethane compositions with a low content of monomeric diisocyanates.
  • trifunctional isocyanates should be used for this purpose, which may be reduced in their functionality to 3.0 ⁇ 0.7 with a monofunctional terminator if necessary.
  • the compositions contain only small amounts of more readily volatile isocyanates.
  • compositions are said to be suitable for use as reactive hot melt adhesives, laminating adhesives, adhesives / sealants, primers, and for the manufacture of foam plastics from disposable pressure containers (aerosol cans).
  • WO2001 / 40342 discloses reactive polyurethane adhesive / sealant compositions which are preparable by reacting diols having a number average molecular weight (Mn) less than 2000 with a large stoichiometric excess of monomeric diisocyanates having a molecular weight less than 500 a high molecular weight diisocyanate.
  • Mn number average molecular weight
  • the unreacted monomeric diisocyanate is removed so that this high molecular weight diisocyanate contains not more than 10% by weight of monomeric diisocyanate.
  • this high molecular weight diisocyanate is reacted with polyols in an NCO / OH ratio of 1, 2: 1 to 10: 1.
  • WO2003 / 055929 describes polyurethane compositions preparable by reactions of polyols with a stoichiometric excess of mixtures of asymmetric polyisocyanates having a molecular weight below 500 and an NCO functionality of 1, 75 to 2.5 and high molecular weight polyisocyanates.
  • These reactive polyurethane compositions are to be prepared in a two-stage reaction, wherein in a first step, the asymmetric or (low molecular weight) polyisocyanates are reacted with polyols and after reacting virtually all higher reactive groups or asymmetric polyisocyanates of the first reaction step of this reaction product with a high molecular weight polyisocyanate in stoichiometric equivalence to the remaining OH groups or preferably in the stoichiometric excess is implemented and the reaction is completed. In this way it should be possible to obtain extremely low residual monomer contents of 0.1% by weight or even lower. Low-viscosity, solvent-free products are not disclosed.
  • WO2003 / 066700 discloses a polyurethane prepolymer which comprises at least one polyisocyanate symmetrically substituted with respect to NCO groups and at least one asymmetrically substituted polyisocyanate with respect to NCO groups, at least one polyol having an OH functionality of more than 2.5 and at least one Polyol having an OH functionality of less than 2.5 can be produced, a process for producing such a polyurethane prepolymer, an adhesive containing at least one such polyurethane prepolymer, and its use, for example, as a color-neutral one-component polyurethane adhesive for bonding porous materials such as wood, Wood materials, paper, cardboard, leather, textiles, non-woven fabrics, natural fibers, synthetic fibers or plastics.
  • a pasty 1-component polyurethane adhesive (1 -K PU adhesive) based on at least one NCO-terminated PU prepolymer and at least one thickening agent and optionally at least one additive is proposed, wherein A) the NCO-terminated PU prepolymer largely linear and B) the thickener should be a finely divided silica in a concentration of 2.0 to 8.0 wt .-%, based on the prepolymer, and C) as an additive less than 10 wt. %, based on the prepolymer should be included. This is intended to meet the practical requirements for a construction and assembly adhesive both in terms of flowability and sag.
  • reactive polyurethanes are disclosed with a low content of monomeric diisocyanates, which are obtainable by selective reaction of at least one monomeric asymmetric diisocyanate having a molecular weight of 160 g / mol to 500 g / mol with at least one diol having a molecular weight of 60 g / mol to 2000 g / mol, without additional work-up and purification steps.
  • Such reactive polyurethanes are suitable for the preparation of reactive one- and two-component adhesives and sealants, mounting foams, casting compounds as well as soft, hard and integral foams, which may possibly be solvent-containing and as a component for the production of reactive hot melt adhesives.
  • Such hot melt adhesive compositions have high melt stability and low melt viscosity in addition to the low level of monomeric diisocyanate.
  • WO2005 / 049684 relates to silyl groups and NCO-bearing polyurethanes or polyureas which can be prepared using asymmetric diisocyanates and substituted alkoxyaminosilanes. Preparations are also described, as well as their use as surface-coating agents, adhesives, assembly foams, potting compounds and soft, hard and integral foams.
  • silane-terminated polymers are well suited as a base raw material for adhesives, sealants and foams and contain no questionable isocyanates. However, they also have disadvantages in some applications. For example, the hydrolysis resistance of the siloxane group is significantly lower than that of a urea or urethane group. This makes it impossible, for example, to use silane-terminated polymers in standard-compliant wood adhesives.
  • the content of monomeric diisocyanate is thus calculated for each individual monomeric diisocyanate and is to be understood as a weight fraction, based on the total weight of the composition.
  • the term "involved in the construction of components (A) and (B)” means that the monomeric diisocyanate in question is incorporated into the molecular skeleton of the PU prepolymer (A) and / or the polyisocyanate (B) by a chemical reaction a composition of the invention has a content of monomeric diisocyanates involved in the construction of components (A) and / or (B) of less than 0.25 wt.%, Particularly preferably less than 0.1 wt.% Per specific monomeric diisocyanate.
  • the total content of the inventive adhesive and / or sealant composition of monomeric diisocyanates is less than 0.1% by weight, and it is particularly preferable for the polymer mixture ((A) + (B)) to contain monomeric diisocyanates of less than 0.1% by weight per monomeric diisocyanate.
  • the NCO content of the monomer-poor PU prepolymer (A) or of the polyisocyanate (B) is to be understood as the proportion by weight of the NCO groups contained in the respective compound, based on the total weight of the compound.
  • the term "low monomer” in the context of the present invention denotes a content of - in the construction of the respective oligomeric or polymeric compound involved - monomeric diisocyanates of less than 1 wt .-%, preferably less than 0.5 wt.% And especially preferably of less than 0.25% by weight, based in each case on the weight of the NCO-terminated PU prepolymer or of the polyisocyanate used.
  • "Monomeric diisocyanates" are compounds of the general structure
  • R is aliphatic, alicyclic or aromatic radicals which may have other, other than isocyanate functional groups and / or heteroatoms. However, R has no oligomeric or polymeric constituents.
  • a polyurethane is understood as meaning any polymer which has more than one urethane grouping -NH-CO-O- per molecule.
  • the content of the composition of monomeric diisocyanates is determined by chromatographic methods.
  • the content of aromatic monomeric diisocyanates is determined by means of gel permeation chromatography (GPC), for aliphatic monomeric diisocyanates GC is used according to DIN EN ISO 10283 (Dec. 2007).
  • compositions according to the invention comprise further additives selected from reactive diluents, plasticizers, solvents, fillers, fibers, defoamers, pigment distributors, catalysts, rheology aids, dyes / pigments, adhesion promoters, blowing agents, stabilizers or mixtures thereof.
  • Another object of the present invention is the use of the aforementioned polyurethane adhesive and / or sealant composition as a one-component wood adhesive or for bonding wood according to the requirements of DIN EN 204 stress group D4 and with a strength of greater than or equal to 6.0 N / mm 2 according to DIN EN 14257.
  • the abovementioned low-monomer NCO-terminated PU prepolymers (A) can be prepared by reacting polyols with diisocyanates and subsequently separating off by distillation the remaining monomeric diisocyanates. Due to their lower NCO content compared to the pure diisocyanates and their high viscosities, however, they are only of limited use when used alone for the production of many adhesives (low heat resistance and hydrolysis resistance).
  • -Monomer polyisocyanates are for example, higher functional homologs of 2,4 '- diphenylmethane diisocyanate, 2,2' diphenylmethane diisocyanate or 4,4 '-Diphenylme- thandiisocyanat (MDI) and isomer mixtures thereof, trimerization products of MDI, 2,4- or 2, 6-tolylene diisocyanate (TDI), or hexamethylene diisocyanate (HDI), or adducts of diisocyanates and low molecular weight triols.
  • the composition according to the invention contains one or more aromatic polyisocyanate (s) as monomer-low polyisocyanate (B).
  • diisocyanates for the preparation of low-monomer NCO-terminated PU prepolymers a large number of diisocyanates can be used. Examples of these are ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,4-tetramethoxybutane diisocyanate, 1,6-hexamethylene diisocyanate (HDI), cyclobutane-1,3-diisocyanate, cyclohexane-1, 3- and -1, 4- diisocyanate, bis (2-isocyanatoethyl) fumarate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 2,4- and 2,6-hexahydrotoluylene diisocyanate, hexahydro-1, 3 or - 1, 4-phenylene diisocyanate, benzidine diisocyanate,
  • cycloalkyl of MDI for example completely hydrogenated MDI (H12-MDI), alkyl substituted diphenylmethane diisocyanates, for example mono-, di-, tri- or tetraalkyl as well as their partially or completely hydrogenated cycloalkyl, 4,4 '-Diisocyanatophenylperfluorethan, Phthalcic - Re-bis-isocyanatoethyl ester, 1-chloromethylphenyl-2,4- or 2,6-diisocyanate, 1-bromomethylphenyl-2,4- or 2,6-diisocyanate, 3,3-bis-chloromethyl ether-4 , 4 ' -Diphenyldiisocyanat, sulfur-containing diisocyanates, as obtainable by reacting 2 moles of diisocyanate with 1 mol of thiodiglycol or Dihydroxydihexylsulfid, the di
  • a polyurethane adhesive and / or sealant composition according to the invention contains as low-monomer NCO-terminated PU prepolymer (A) one or more PU prepolymers (s) based on aromatic diisocyanates.
  • aromatic diisocyanates are used to prepare the low-monomer NCO-terminated PU prepolymers (A).
  • aromatic diisocyanates are used to prepare the low-monomer NCO-terminated PU prepolymers (A).
  • aromatic diisocyanates are used to prepare the low-monomer NCO-terminated PU prepolymers (A).
  • aromatic diisocyanates are used to prepare the low-monomer NCO-terminated PU prepolymers (A).
  • Particularly preferred are the commercially good available MDI and / or TDI because of their high reactivity and the relatively easy removability of the residual monomers from the synthesis mixture.
  • polyols a plurality of relatively high molecular weight polyhydroxy compounds can be used.
  • Suitable polyols are preferably the liquid at room temperature, glassy solid / amorphous or crystalline polyhydroxy compounds having two or three hydroxyl groups per molecule in the molecular weight range of 200 to 20,000, preferably in the range of 400 to 6000, most preferably from 400 to 2000.
  • Examples are di- and / or trifunctional polypropylene glycols or polypropylene oxides, it is also possible to use random and / or block copolymers of ethylene oxide and propylene oxide.
  • polyethers are the polytetramethylene glycols or polytetramethylene oxides (poly (oxytetramethylene) glycol, polyTHF), which are e.g. are prepared by the acidic polymerization of Tetra h yd rofu ran, while the molecular weight range of polytetramethylene glycols (poly-THF) between 400 and 6000, preferably in the range of 400 to 2000.
  • suitable polyols are the liquid polyesters obtained by condensation of di- or tricarboxylic acids, such as e.g. Adipic acid, sebacic acid, glutaric acid, azelaic acid, suberic acid, undecanedioic acid, dodecanedioic acid, 3,3-dimethylglutaric acid, terephthalic acid, isophthalic acid, hexahydrophthalic acid, dimer fatty acid or mixtures thereof with low molecular weight diols or triols, e.g.
  • di- or tricarboxylic acids such as e.g. Adipic acid, sebacic acid, glutaric acid, azelaic acid, suberic acid, undecanedioic acid, dodecanedioic acid, 3,3-dimethylglutaric acid, terephthalic acid, isophthalic acid, hexahydrophthalic acid, dimer fatty acid or mixtures thereof with low molecular
  • Ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, 1, 4-butanediol, 1, 6-hexanediol, 1, 8-octanediol, 1, 10-decanediol, 1, 12-dodecanediol, dimer fatty alcohol, glycerol, trimethylolpropane or mixtures thereof can.
  • polyesters based on ⁇ -caprolactone also called “polycaprolactones”.
  • polyester polyols of oleochemical origin can be prepared, for example, by complete ring opening of epoxidized triglycerides of an at least partially olefinically unsaturated fatty acid-containing fatty mixture with one or more alcohols having 1 to 12 carbon atoms and subsequent partial transesterification of the triglyceride derivatives to alkyl ester polyols having 1 to 12 carbon atoms in the alkyl radical become.
  • Other suitable polyols are polycarbonate polyols and dimer diols (Cognis Deutschland GmbH, Dusseldorf) and castor oil and derivatives thereof.
  • the hydroxy-functional polybutadienes, such as those under the trade name "Poly-bd" can be used as polyols for the compositions according to the invention.
  • polyols are linear and / or weakly branched acrylic ester copolymeric polyols which are obtained, for example, by the free-radical copolymerization of acrylic acid esters or methacrylic acid esters with hydroxy-functional acrylic and / or methacrylic acid compounds, such as hydroxyethyl (meth) acrylate or hydroxypropyl ( Meth) acrylate can be produced. Because of this method of preparation, the hydroxyl groups in these polyols are usually randomly distributed, so that these are either linear or slightly branched polyols having an average OH functionality. Although the difunctional compounds are preferred for the polyols, higher functionality polyols can also be used, at least in minor amounts.
  • the monomer-poor NCO-terminated PU prepolymer (A) is preferably obtainable by reacting polyols with diisocyanates at a stoichiometric ratio of the isocyanate groups to hydroxyl groups of greater than 2: 1, preferably greater than 4: 1.
  • the ratio of isocyanate groups to hydroxyl groups can be 4.5: 1 or 5: 1.
  • the unreacted residual monomer or the monomer mixture is separated by thin-layer distillation, short-path distillation, optionally under high vacuum, or by passing inert gas in countercurrent, with residual monomer contents of less than 0.1 wt.% become.
  • the PU prepolymers (A) have levels of reactive isocyanate groups (NCO values) of from 3 to 20%, preferably from 5 to 15%.
  • triisocyanates can also be used, such as, for example, the thiophosphoric acid tris- (p-isocyanato-phenyl ester), the triphenylmethane-4,4 ', 4 "-triisocyanate and in particular the various isomeric trifunctional homologues of diphenylmethane diisocyanate (MDI), the latter of which include predominantly isocyanato-bis ((4-isocyanatophenyl) methyl) benzene, 2-isocyanato-4 - ((3-isocyanatophenyl) methyl) -1 - ((4-isocyanatophenyl) methyl) benzene, the 4-iso-cyanato-1,2-bis ((4-isocyanatophenyl) methyl) benzene, the 1-isocyanato-4 - ((2- isocyanatophenyl) methyl
  • triisocyanates are adducts of diisocyanates and low molecular weight triols, in particular the adducts of aromatic diisocyanates and triols such as, for example, trimethylolpropane or glycerol. These adducts also have the abovementioned restrictions with regard to the diisocyanate content and the higher-functional constituents.
  • Aliphatic triisocyanates such as, for example, the biuretization product of hexamethylene diisocyanate (HDI) or the isocyanuration product of HDI or else the same trimerization products of isophorone diisocyanate (IPDI), are suitable for the compositions according to the invention, provided that the proportion of diisocyanates is not more than 0.5% by weight. preferably not more than ⁇ 0.1% by weight.
  • the low-monomer polyisocyanates (B) can be freed from monomeric diisocyanate by thin-layer distillation, short-path distillation, if necessary in a high vacuum, or by passage of inert gas in countercurrent, with residual monomer contents of less than 0.1% by weight being sought.
  • the low monomer polyisocyanates (B) have an NCO content of 10 to 40%, preferably 15 to 35%.
  • a reactive diluent e.g. use the following substances: polyalkylene glycols reacted with isocyanatosilanes (eg Synalox 100-50B, DOW), carbamatopropyltrimethoxysilane, alkyltrimethoxysilane, alkyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane and vinyltrimethoxysilane (Dynasylan VTMO, Evonik or Geniosil XL 10, from Wacker), vinyltriethoxysilane, phenyltrimethoxysilane, Phenyltriethoxysilane, octyltrimethoxysilane, tetraethoxysilane, vinyldimethoxymethylsilane (Geniosil XL12, Wacker), vinyltriethoxysilane (Geniosil GF56, Wacker), vinyltriacetoxys
  • the adhesive and / or sealant composition of the invention preferably comprises a reactive diluent based on a silane having two or three hydrolyzable groups. Most preferably, this silane contains a vinyl group. Such silanes can also function as desiccants and crosslinkers in an adhesive or sealant according to the invention.
  • Suitable plasticizers are, for example, adipic acid esters, azelaic acid esters, benzoic acid esters, butyric acid esters, acetic acid esters, esters of higher fatty acids containing from about 8 to about 44 carbon atoms, esters containing OH groups or epoxidized fatty acids, fatty acid esters and fats, glycolic esters, phosphoric esters, phthalic acid esters Linear or branched alcohols containing 1 to 12 carbon atoms, propionic acid esters, sebacic acid esters, sulfonic acid esters (eg "MesamoH", phenylsulfonylate, Lanxess), thiobutyric acid esters, trimellitic acid esters, citric esters and esters based on nitrocellulose and polyvinyl acetate, and mixtures of two or more More particularly suitable are the asymmetric esters of adipic acid monooctyl ester with 2-ethy
  • adipates include dioctyl adipate (DOA), diisodecyl adipate, diisodecyl succinate, dibutyl sebacate or butyl oleate.
  • DOA dioctyl adipate
  • the preferred solvents also used have a boiling range of about 5O 0 C to 14O 0 C.
  • halogenated hydrocarbons are suitable, are particularly particularly petroleum benzine (100-145), ⁇ -butyrolactone, propylene carbonate or occasionally ethyl acetate, methyl ethyl ketone (MEK) or Acetone is preferred.
  • the adhesives and / or sealants of the invention may additionally contain fillers.
  • fillers For example, chalk, limestone, precipitated and / or fumed silica, microsilica, zeolites, bentonites, magnesium carbonate, kieselguhr, clay, clay, talc, titanium oxide, iron oxide, zinc oxide, sand, quartz, flint, mica, glass powder and other ground minerals are suitable here .
  • organic fillers can be used, in particular carbon black, graphite, wood fibers, wood flour, sawdust, pulp, cotton, jute, hemp, pulp, wood chips, chaff, chaff, ground walnut shells and other fiber short cuts.
  • short fibers such as glass fiber, glass filament, polyacrylonitrile, carbon fiber, Kevlar fiber, polyester fibers, polypropylene fibers, polyamide fibers or even polyethylene fibers can be added.
  • Aluminum powder is also suitable as a filler.
  • compositions according to the invention may additionally comprise catalysts which accelerate the crosslinking of moisture after the application of the adhesive or sealant.
  • Suitable catalysts for use in accordance with the invention are e.g. the organometallic compounds of tin, iron, titanium or bismuth, such as stannous salts of carboxylic acids, e.g. Tin II acetate, ethyl hexoate and diethyl hexoate.
  • carboxylic acids e.g. Tin II acetate, ethyl hexoate and diethyl hexoate.
  • Another class of compounds are the dialkyl-tin (IV) carboxylates.
  • the carboxylic acids have 2, preferably at least 10, in particular 14 to 32 C-atoms. It is also possible to use dicarboxylic acids.
  • acids are expressly mentioned: adipic acid, maleic acid, fumaric acid, malonic acid, succinic acid, pimelic acid, terephthalic acid, phenylacetic acid, benzoic acid, acetic acid, propionic acid and 2-ethylhexane, caprylic, capric, lauric, myristic, palmitic and stearic.
  • Specific compounds are dibutyl and dioctyltin diacetate, maleate, bis (2-ethylhexoate), dilaurate, tributyltin acetate, bis (.beta.-methoxycarbonyl-ethyl) tin dilaurate and bis (.beta.-acetyl-ethyl) tin dilaurate.
  • Tin oxides and sulfides and thiolates are also useful. Concrete compounds are: bis (tributyltin) oxide, bis (trioctyltin) oxide, dibutyl- and dioctyltin bis (2-ethylhexylthiolate) dibutyl- and dioctyltin dodecylthiolate, bis ( ⁇ -methoxycarbonyl-ethyl) tindidodecylthiolate, bis ( ⁇ -acetylthiolate) ethyl) tin bis (2-ethylhexyl thiolate), dibutyl and dioctyl tin dodecyl thiolate, butyl and octyl tin ths (thioglycolic acid 2-ethylhexoate), dibutyl and dioctyltin bis (thioglycolic acid 2-ethylhexoate),
  • Bis ( ⁇ -methoxycarbonylethyl) tin bis (thioethylene glycol 2-ethylhexanoate), bis ( ⁇ -methoxycarbonylethyl) tin bis (thioglycolic acid 2-ethylhexanoate), and bis ( ⁇ -acetylethyl) tin bis (thioethylene glycol 2-ethylhexoate) and bis ( ⁇ -acetyl-ethyl) tin bis (thioglycolic acid 2-ethylhexoate.
  • tertiary amines in particular with cyclic structure.
  • tertiary amines those which additionally carry reactive groups relative to the isocyanates, in particular hydroxyl and / or amino groups.
  • Diazabicycloundecene (DBU) and Texacat DP-914 (Texaco Chemical), N, N, N, N-tetramethylbutane-1, 3-diamine, N, N, N, N-tetramethylpropane-1,3-diamine and N, N, N, N-tetramethylhexane-1,6-diamine.
  • the catalysts may also be in oligomerized or polymerized form, e.g. as N-methylated polyethyleneimine.
  • catalysts are the derivatives of morpholine.
  • suitable morpholino compounds are bis (2- (2,6-dimethyl-4-morpholino) ethyl) - (2- (4-morpholino) ethyl) amine, bis (2- (2,6-dimethyl-4 -morpholino) ethyl) - (2- (2,6-diethyl-4-morpholino) ethyl) amine, tris (2- (4-morpholino) ethyl) amine, tris (2- (4-morpholino) propyl) amine, Tris (2- (4-morpholino) butyl) amine, tris (2- (2,6-dimethyl-4-morpholino) ethyl) amine, tris (2- (2,6-diethyl-4-morpholino) ethyl) amine , Tris (2- (2-methyl-4-morpholino) ethyl) amine or tris (2- (2-eth) amine or tri
  • the abovementioned morpholine derivatives have a particularly high catalytic activity, in particular with respect to the water (moisture) isocyanate reaction. Therefore, even very low catalyst concentrations are highly efficient for crosslinking or curing of the adhesives, the concentrations of the catalyst in the adhesive formulation may be between 0.001 and 6% by weight, preferably between 0.05 and 2.0% by weight.
  • an adhesive and / or sealant composition of the invention contains a rheology aid.
  • a rheology aid e.g. Bentone, fumed silicas, urea derivatives, polyamide waxes, hydrogenated fatty acid derivatives, fibrillated or PuIp short fibers may be included. Typical amounts are between 0, 1 and 8 wt.%, Preferably between 0.5 and 5 wt.%.
  • a polyamide wax is contained as a rheology aid.
  • an adhesive and / or sealant composition according to the invention contains a rheology aid and a reactive diluent, preferably a polyamide wax as rheology aid and a silane, more preferably a vinyl silane, as a reactive diluent.
  • a rheology aid and a reactive diluent preferably a polyamide wax as rheology aid and a silane, more preferably a vinyl silane, as a reactive diluent.
  • Suitable pigments are titanium dioxide, iron oxides or carbon black.
  • blowing agents are in principle all known blowing agents such.
  • the "chemical blowing agents” which release gases by decomposition or “physical blowing agents", i. expanding hollow spheres.
  • the former blowing agents are azobisisobutyronitrile, azodicarbonamide, di-nitrosopentamethylenetetramine, 4,4'-oxybis (benzenesulfonic acid hydrazide), diphenylsulfone-3,3'-disulfohydrazide, benzene-1,3-disulfohydrazide, p-toluenesulfonyl semicarbazide.
  • Examples of the preferred physical blowing agents are expandable plastic microbubbles based on polyvinylidene chloride copolymers or acrylonitrile / (meth) acrylate copolymers, e.g. under the names "Dualite” and “Expancel” from the companies Henkel and Akzo Nobel are commercially available.
  • stabilizers are, on the one hand, stabilizers which have a viscosity stability of the polyurethane prepolymer during production, storage or effect application.
  • monofunctional carboxylic acid chlorides, monofunctional highly reactive isocyanates, but also non-corrosive inorganic acids are suitable, for example, be mentioned benzoyl chloride, toluenesulfonyl isocyanate, phosphoric acid or phosphorous acid.
  • stabilizers for the purposes of this invention are to be understood as meaning antioxidants, UV stabilizers or hydrolysis stabilizers.
  • antioxidants if necessary in combination with UV protectants, are necessary in most cases. Examples of these are the commercially available sterically hindered phenols and / or thioethers and / or substituted benzotriazoles or the sterically hindered amines of the HALS type ("Hindered Amine Light Stabilizer").
  • hydrolysis stabilizers e.g. carbodiimide type.
  • compositions according to the invention contain mixtures of the PU prepolymer (s) (A) and the polyisocyanate (s) (B) and optionally further constituents, in particular additives.
  • the polyurethane adhesive and / or sealant compositions according to the invention are distinguished by the fact that the compositions have a content of volatile, monomeric diisocyanates having a vapor pressure of 25 ° C from 0.05 hPa to 5 * 10 "4 hPa of less than 0.05% by weight and a content of monomeric diisocyanates having a vapor pressure at 25 ° C of 5 * 10 " 4 hPa to 9 * 10 "6 hPa of less than 0.1% by weight.
  • S-TDI Was analogous by reaction of polypropylene glycol (diol) with Mn 400 with TDI
  • Aerosil R 202 (Degussa / Evonik): silica (filler)
  • Disparlon 6500 Korean Chemicals: polyamide wax (rheological aids)
  • DMDEE 2,2-dimorpholinodiethyl ether (crosslinking catalyst)
  • the viscosity was determined as follows: Brookfield RVT viscometer, spindle 6, at 20 rpm and 23 0 C.
  • MDI have too high viscosity (not measurable at RT) and therefore can not be processed properly (V1 & V2). Even a mixture has too high a viscosity, bad
  • the demonomerized p-MDl has too high a viscosity and, despite high NCO
  • V4 Water resistance
  • Tolunate HDT-LV is thin and easy to process, has a high NCO value and good dry strength according to DIN EN 204 D1. However, the water resistance according to DIN EN 204 D4 and the gap strength on solid beech are very low (V5).

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Polyurethanes Or Polyureas (AREA)
  • Sealing Material Composition (AREA)

Abstract

L'invention concerne des compositions d'adhésif et/ou de joint polyuréthane à un composant, contenant (A) au moins un prépolymère de polyuréthane à terminaison NCO à faible teneur en monomères, ayant une teneur en NCO inférieure à 20 %, et (B) au moins un polyisocyanate à faible teneur en monomères, ayant une fonction isocyanate supérieure ou égale à 2,0, et une teneur en NCO supérieure à 10 %, le mélange polymère ayant une teneur en diisocyanates monomères impliqués dans la constitution des composants (A) et/ou (B), inférieure à 0,5 % en poids par diisocyanate spécifique. Lesdites compositions d'adhésif et/ou de joint polyuréthane à un composant peuvent servir d'adhésif à bois selon les exigences de DIN EN 204 Groupe de résistance D4, présentant une résistance supérieure ou égale à 6,0 N/mm 2 selon DIN EN 14257.
EP09753935A 2008-05-29 2009-05-28 Adhésifs réactifs ayant une très faible teneur en diisocyanates monomères Withdrawn EP2288635A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102008025793A DE102008025793A1 (de) 2008-05-29 2008-05-29 Reaktive Klebstoffe mit sehr geringem Gehalt an monomeren Diisocyanaten
PCT/EP2009/056551 WO2009144280A1 (fr) 2008-05-29 2009-05-28 Adhésifs réactifs ayant une très faible teneur en diisocyanates monomères

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DE102009046050A1 (de) * 2009-10-27 2011-04-28 Henkel Ag & Co. Kgaa PU-Klebstoff mit Viskositätsregler
DE102010028269A1 (de) * 2010-04-27 2011-10-27 Henkel Ag & Co. Kgaa PU-Klebstoff mit Fließgrenze
DE102010060443A1 (de) * 2010-11-09 2012-05-10 Fischerwerke Gmbh & Co. Kg Harz für Kleb- und Beschichtungsstoffe auf Basis silanterminierter Harze mit mindestens zwei Edukten
JP6161866B2 (ja) * 2010-12-21 2017-07-12 ローム アンド ハース カンパニーＲｏｈｍ Ａｎｄ Ｈａａｓ Ｃｏｍｐａｎｙ 接着剤組成物
EP2481764A1 (fr) * 2011-01-27 2012-08-01 de Schrijver, Aster Composition pour mousses de polyuréthane à un seul composant dotée d'un contenu à faible teneur en MDI monomérique
DE102012200018A1 (de) * 2012-01-02 2013-07-04 Bayer Materialscience Ag Reaktive Polyurethan-Zubereitungen
EP2644633A1 (fr) 2012-03-29 2013-10-02 Huntsman International Llc Prépolymère à base d'isocyanate
EP2644632A1 (fr) 2012-03-29 2013-10-02 Huntsman International Llc Prépolymère à base d'isocyanate
EP2706074A1 (fr) * 2012-09-07 2014-03-12 Den Braven Beheer B.V. Compositions de polyuréthane à faible teneur en monomère pour conteneurs d'aérosol
JP2015535880A (ja) * 2012-10-03 2015-12-17 スリーエム イノベイティブ プロパティズ カンパニー コーティング組成物及びそれらから製造される物品
FR3021658B1 (fr) * 2014-05-28 2017-12-08 Bostik Sa Composition de polyurethane a terminaisons nco a base mdi non thermofusible et a faible teneur en monomere mdi, comprenant au moins un compose isocyanate de volume molaire particulier.
FR3021659B1 (fr) * 2014-05-28 2017-11-17 Bostik Sa Composition de polyurethane a terminaisons nco a base de 2,4-tdi non thermofusible et a faible teneur en monomere tdi, comprenant au moins un compose isocyanate de volume molaire particulier.
CN110139885A (zh) 2017-01-11 2019-08-16 陶氏环球技术有限责任公司 具有减少的滑动的聚氨酯玻璃粘合胶粘剂

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