Linear isocyanate group-containing polymer

Abstract

The present invention relates to a linear polymer containing isocyanate groups having an NCO content in the range of 0.3 wt% to 1.5 wt% and a monomeric diisocyanate content of 0.5 wt% or less, characterized by being obtained by removing most of the monomeric aromatic diisocyanate by a suitable separation method following a reaction of at least one monomeric aromatic diisocyanate with a polyether diol having an OH value in the range of 5 to 21 mg KOH / g at an NCO / OH ratio of at least 5 / 1; and a moisture-curing polyurethane composition having a monomeric diisocyanate content of less than 0.1 wt% comprising said polymer. The polymer of the present invention enables an elastic adhesive having high elongation, remarkably high strength, and remarkably good adhesion to a plastic substrate.

Description

Technology Field

[0001] The present invention relates to a polymer having a low monomer level for a moisture-curing polyurethane composition and its use as an elastic adhesive having excellent adhesion to a plastic substrate. Background Technology

[0002] Polyurethane compositions that provide an elastomer by crosslinking and curing through the reaction of isocyanate groups with moisture or water are used as elastic adhesives or sealants in the construction and manufacturing industries, particularly for joining parts in assemblies or filling joints. Due to their adhesive strength and elasticity, they can gently dampen and buffer forces acting on a substrate, for example, triggered by vibration or temperature changes.

[0003] These polyurethane compositions contain a polymer containing isocyanate groups as a binder, prepared by reacting a polyol with a monomeric diisocyanate. The polymer thus obtained typically contains a residual monomeric diisocyanate content in the range of 1% to 3% by weight due to chain extension reactions. Monomeric diisocyanates can be potentially harmful to health. In particular, formulations containing monomeric diisocyanates at a concentration exceeding 0.1% by weight must provide hazard symbols and warning messages on the label and in the data sheet, and may be subject to regulations regarding sale and use in some countries. Therefore, there is particular interest in polyurethane compositions having a low content of monomers, less than 0.1% by weight.

[0004] An attractive route for polymers containing isocyanate groups with a low monomeric diisocyanate content is to use an excess of monomeric diisocyanate in the preparation of the polymer and then remove most of the unconverted monomeric diisocyanate by distillation. This route is particularly easy to implement with low molecular weight, and therefore volatile, monomeric diisocyanates, such as, for example, hexane diisocyanate. However, polymers based on this result in slow curing and low mechanical strength of the product.

[0005] Polymer-based diphenylmethane 4,4'-diisocyanate (4,4'-MDI) enables high strength combined with high elasticity. However, manufacturing is much more difficult due to the low volatility of 4,4'-MDI when any excess monomer is distilled off.

[0006] Elastic adhesives for bonding plastic substrates are increasingly in demand in industry for bonding, for example, headlamp housings or panoramic roofs of vehicles, organic glass for ships or trains, or various parts of caravans. Here, the adhesive must cure quickly and reliably, possess high strength and be highly elastic, and maintain high adhesive strength even under thermal and moisture stress without complex pretreatment of the plastic substrate. However, adhesives based on polymers with low monomer levels show weakness in increasing adhesion to plastic substrates, particularly because they are substantially lacking in monomeric diisocyanates.

[0007] Accordingly, the object of the present invention is to provide a polymer having a low content of monomeric diisocyanate that enables an elastic adhesive having reliable curing and high strength and having no labeling requirements, and significantly improves its adhesion to a plastic substrate.

[0008] This objective is achieved by a linear polymer as described in claim 1. The polymer has an NCO content in the range of 0.3 wt% to 1.5 wt% and is based on an aromatic monomeric diisocyanate, in particular diphenylmethane 4,4'-diisocyanate, and a polyether diol having an OH number in the range of 5 to 21 mg KOH / g. The polymer of the present invention is linear, has a high chain length, and has a low monomeric diisocyanate content. It is liquid at room temperature, has relatively low viscosity, and exhibits excellent storage stability in the absence of moisture. This enables an elastic adhesive with an attractive EHS classification and remarkably good adhesion to plastic substrates, such as PVC, PMMA, or polycarbonate, even under thermal and water stress. Particularly surprising here is the fact that the polymer of the present invention imparts excellent mechanical properties to the adhesive, particularly high strength (tensile strength and modulus of elasticity), which were not expected in such long-chain linear polymers. Compared to polymers based on shorter chain polyether diols, the polymer of the present invention, having comparable mechanical properties, achieves significantly better adhesion to plastic substrates.

[0009] Further aspects of the present invention are the subject of additional independent claims. Particularly preferred embodiments of the present invention are the subject of dependent claims. Specific details for implementing the invention

[0010] The present invention provides a linear polymer containing isocyanate groups having an NCO content in the range of 0.3 wt% to 1.5 wt% and a monomeric diisocyanate content of 0.5 wt% or less, wherein the linear polymer is obtained by removing most of the monomeric aromatic diisocyanate by a suitable separation method following a reaction of at least one monomeric aromatic diisocyanate with a polyether diol having an OH value in the range of 5 to 21 mg KOH / g at a ratio of at least 5 / 1 NCO / OH.

[0011] "Monomer diisocyanate" refers to an organic compound having two isocyanate groups separated by a divalent hydrocarbyl radical having 4 to 15 carbon atoms.

[0012] "Aromatic" isocyanate groups refer to those directly bonded to aromatic carbon atoms. Isocyanates having exclusively aromatic isocyanate groups are correspondingly referred to as "aromatic isocyanates."

[0013] "Aliphatic" isocyanate groups refer to those directly bonded to aliphatic or cycloaliphatic carbon atoms. Isocyanates having exclusively aliphatic isocyanate groups are correspondingly referred to as "aliphatic isocyanates."

[0014] "Monomeric aromatic diisocyanate" refers to a monomeric diisocyanate having an aromatic isocyanate group.

[0015] "NCO content" refers to the content of isocyanate groups (weight%).

[0016] "Molecular weight" refers to the molar mass (in g / mol) of a molecule or molecular residue. "Average molecular weight" refers to the number-average molecular weight (M) of a polydisperse mixture of oligomer or polymer molecules or molecular residues. nIt refers to ). This is determined by gel-penetration chromatography (GPC) on polystyrene as a standard.

[0017] A substance or composition is referred to as having "storage stability" or "storability" if it can be stored at room temperature in a suitable container for an extended period, typically for at least 3 months, preferably up to 6 months, without causing any change in its application or use characteristics to the extent related to use.

[0018] "Plastic" refers to an organic material based on macromolecules.

[0019] "Room temperature" refers to a temperature of 23℃.

[0020] All industrial standards and norms mentioned in this specification relate to the versions valid on the date of the first filing.

[0021] Weight percentage (wt%), abbreviated as wt%, refers to the ratio of the mass of a component of a composition or molecule based on the total composition or total molecule, unless otherwise stated. The terms “mass” and “weight” are used as synonyms in this specification.

[0022] The polymer of the present invention containing isocyanate groups may also be referred to as a prepolymer.

[0023] The polymer of the present invention preferably has an NCO content in the range of 0.5 wt% to 1.3 wt%, particularly 0.7 wt% to 1.1 wt%.

[0024] More preferably, the polymer has an NCO content in the range of 0.8 wt% to 1.1 wt%, particularly 0.9 wt% to 1.1 wt%. Such a polymer enables a particularly storage-stable composition having very good adhesion to a plastic substrate.

[0025] The polymer of the present invention preferably has a monomeric diisocyanate content of 0.3 weight% or less, particularly 0.2 weight% or less. Such polymers are particularly suitable for the manufacture of moisture-curing polyurethane compositions having a monomeric diisocyanate content of less than 0.1 weight%; and since they can be safely handled without special safety precautions, they can be sold in many countries without hazard labels.

[0026] Suitable monomeric aromatic diisocyanates are mixtures thereof with diphenylmethane 4,4'-diisocyanate, tolylene 2,4-diisocyanate or tolylene 2,6-diisocyanate (TDI), phenylene 1,4-diisocyanate (PDI), 2,3,5,6-tetramethyl-1,4-diisocyanatobenzene, naphthalene 1,5-diisocyanate (NDI), or 3,3'-dimethyl-4,4'-diisocyanatodiphenyl (TODI), with fractions of diphenylmethane 2,4'- and / or 2,2'-diisocyanate (MDI), in particular, optionally.

[0027] Among these, diphenylmethane 4,4'-diisocyanate, tolylene 2,4-diisocyanate, or phenylene 1,4-diisocyanate are preferred.

[0028] A particularly desirable monomeric aromatic diisocyanate is diphenylmethane 4,4'-diisocyanate (4,4'-MDI). This 4,4'-MDI is of a quality containing only a small fraction of diphenylmethane 2,4'- and / or 2,2'-diisocyanate and is solid at room temperature. This enables adhesives with fast curing and particularly high strength, combined with particularly high extensibility and elasticity.

[0029] 4,4'-MDI is preferably distilled and has a purity of at least 95%, particularly at least 97.5%.

[0030] Commercially available diphenylmethane 4,4'-diisocyanate of this quality is, for example, Desmodur ® 44 MC (Covestro product) or Lupranat ® MRS or ME (BASF product) or Suprasec ® It is 1400 (a Huntsman product).

[0031] The polyether diol preferably contains repeating units selected from the group consisting of 1,2-ethyleneoxy, 1,2-propyleneoxy, 1,3-propyleneoxy, 1,2-butyleneoxy, and 1,4-butyleneoxy. 1,2-propyleneoxy groups having or not having a predetermined proportion of 1,2-ethyleneoxy groups are preferred.

[0032] More particularly, the polyether diol contains 80% to 100% by weight of 1,2-propylene oxygen groups and 0% to 20% by weight of 1,2-ethylene oxygen groups.

[0033] When a polyether diol contains 1,2-ethyleneoxy groups, the 1,2-propyleneoxy groups and 1,2-ethyleneoxy groups each preferably form a homogeneous block, and the poly(1,2-ethyleneoxy) block is at the chain end.

[0034] Polyether diols preferably have an OH value in the range of 6 to 19 mg KOH / g, particularly 9 to 14 mg KOH / g, and most preferably 12 to 14 mg KOH / g.

[0035] The polyether diol preferably has an average molecular weight M in the range of 5,500 to 20,000 g / mol, more preferably 6,000 to 18,000 g / mol, particularly 8,000 to 12,000 g / mol, and most preferably 8,000 to 9,000 g / mol. n has

[0036] Polyether diols preferably have an average OH functional group of at least 1.8, particularly at least 1.9. As a result of their production, commercial polyether diols contain a predetermined amount of monool as a result of having an average OH functional group of typically slightly less than 2.

[0037] The polyether diol preferably has an unsaturated level of less than 0.02 meq / g, particularly less than 0.01 meq / g, as measured by ASTM D-2849-69. Polyether diols having an unsaturated level of less than 0.01 meq / g were prepared particularly with the help of so-called bimetallic cyanide complex catalysts (DMC catalysts).

[0038] The polyether diol has OH groups in the range of 6 to 19 mg KOH / g, preferably 9 to 14 mg KOH / g, most preferably 12 to 14 mg KOH / g, and at least 1.9 average OH functional groups.

[0039] Suitable polyether diols are, for example, Acclaim ® Polyol 8200 N, Acclaim ® Polyol 12200 N, Acclaim ® Polyol 18200 N (all Covestro products), or Preminol ® S 4013 F (Asahi Glass product) is commercially available.

[0040] Preferably, the polymer of the present invention has an average molecular weight M in the range of 6,000 to 40,000 g / mol, determined by gel permeation chromatography (GPC) versus tetrahydrofuran as the mobile phase, polystyrene as a standard, and a refractive index detector. n has

[0041] More preferably, average molecular weight M n The range is 8,000 to 30,000 g / mol, particularly 8,000 to 15,000 g / mol.

[0042] The polymer of the present invention is obtained from the reaction of at least one monomeric aromatic diisocyanate with an NCO / OH ratio of at least 5 / 1 and a polyether diol.

[0043] The NCO / OH ratio is preferably in the range of 5 / 1 to 20 / 1, more preferably in the range of 6 / 1 to 15 / 1, and particularly in the range of 7 / 1 to 13 / 1.

[0044] The reaction is preferably carried out in the presence of a suitable catalyst, at a temperature ranging from 20 to 160°C, particularly from 40 to 140°C, with the exclusion of moisture.

[0045] After the reaction, the monomeric diisocyanate remaining in the reaction mixture is removed by a suitable separation method up to the stated residual content.

[0046] A preferred separation method is a distillation method, preferably with the application of reduced pressure, in particular thin-film distillation or short-path distillation.

[0047] A multi-stage method in which monomeric aromatic diisocyanates are removed in a short-path evaporator having a jacket temperature in the range of 120 to 200°C and a pressure of 0.001 to 0.5 mbar is particularly preferred.

[0048] In the case of 4,4'-MDI, which is preferred as a monomeric aromatic diisocyanate, distillation removal is particularly difficult. For example, it must be ensured that the condensate does not solidify and does not block the system. It is preferred to operate at a jacket temperature in the range of 160 to 200°C at 0.001 to 0.5 mbar and to condense the removed monomer at a temperature in the range of 40 to 60°C.

[0049] It is preferred to combine monomeric aromatic diisocyanates with polyether diols and then remove most of the monomeric diisocyanates remaining in the reaction mixture without using a solvent or entraining agent.

[0050] It is preferred to subsequently reuse the aromatic monomeric diisocyanate removed after the reaction, that is, to reuse it for the production of polymers containing isocyanate groups.

[0051] Most preferably, the polymer containing isocyanate groups has an NCO content in the range of 0.5 wt% to 1.3 wt% and a monomeric diisocyanate content of 0.3 wt% or less. Such a polymer is particularly suitable for elastic adhesives having good adhesion to plastic substrates, good mechanical properties, and good EHS classification.

[0052] The polymer of the present invention is liquid at room temperature and has a relatively low viscosity. This is preferably 80 Pa . s or less, especially 70 Pa . s or less, more preferably 60 Pa . It has a viscosity of s or less at 20°C. The viscosity is 10 s in this specification. -1 The shear rate is determined by a cone-plate viscometer.

[0053] In the reaction, the OH groups in the polyether diol react with the isocyanate groups in the monomeric aromatic diisocyanate. This also results in a so-called chain extension reaction, in that there is a reaction between the OH groups and / or isocyanate groups of the reaction product between the diol and the monomeric diisocyanate. The higher the selected NCO / OH ratio, the lower the chain extension reaction occurs, and the polydispersity of the obtained polymer, and consequently the viscosity, decreases. Measures of the chain extension reaction are the average molecular weight of the polymer or the peak width and distribution in GPC analysis. An additional measure is the effective NCO content of the monomer-free polymer compared to the theoretical NCO content calculated from the reaction of all OH groups with the monomeric aromatic diisocyanate.

[0054] The polymer of the present invention preferably contains only a low content of chain-extending components. The NCO content in the polymer of the present invention is preferably at least 90%, particularly at least 95%, of the theoretical NCO content calculated from the addition of 1 mole of monomeric diisocyanate per 1 mole of OH groups in the polyether diol.

[0055] The polymer of the present invention has low viscosity, contains a low content of monomeric diisocyanate, and exhibits high storage stability in a moisture-excluded state. This is particularly suitable for the manufacture of elastic adhesives having rapid curing, high strength, high elongation, and particularly good adhesion to plastic substrates.

[0056] The present invention also provides a moisture-curing polyurethane composition having a content of less than 0.1 weight% of monomeric diisocyanate, comprising a linear polymer of the present invention containing isocyanate groups.

[0057] The moisture-curing polyurethane composition preferably has a content of the polymer of the present invention in the range of 5% to 80% by weight, particularly 10% to 70% by weight, and more preferably 20% to 60% by weight, based on the total composition.

[0058] In addition to the polymer of the present invention, the moisture-curing polyurethane composition may contain at least one additional polymer containing an isocyanate group that does not correspond to the polymer of the present invention.

[0059] Suitable additional polymers containing isocyanate groups are conventionally manufactured polymers or other polymers without monomers. Additional polymers containing aromatic isocyanate groups are suitable, but polymers containing aliphatic isocyanate groups are also suitable.

[0060] A suitable additional polymer containing isocyanate groups is obtained from the reaction of at least one polyol and a super stoichiometric amount of at least one diisocyanate. This reaction is preferably carried out in the exclusion of moisture at a temperature in the range of 20 to 160°C, particularly 40 to 140°C, in the presence of a suitable catalyst, optionally.

[0061] The NCO / OH ratio is preferably in the range of 1.3 / 1 to 10 / 1. Monomeric diisocyanates remaining in the reaction mixture after the reaction of the OH groups can be removed, in particular, by distillation.

[0062] When monomeric diisocyanate is removed from the polymer by distillation, the NCO / OH ratio in the reaction is preferably in the range of 3 / 1 to 10 / 1, and the polymer containing isocyanate groups obtained after distillation preferably contains 0.5 weight% or less, more preferably 0.3 weight% or less of monomeric diisocyanate.

[0063] When monomeric diisocyanate is removed from the polymer, the NCO / OH ratio in the reaction is preferably in the range of 1.3 / 1 to 2.5 / 1. Such a polymer contains, in particular, 3.5 weight% or less, preferably 2 weight% or less of monomeric diisocyanate.

[0064] A preferred monomeric diisocyanate is the previously mentioned aromatic diisocyanate, as well as an aliphatic or cycloaliphatic diisocyanate, in particular MDI, TDI, hexane 1,6-diisocyanate (HDI), isophorone diisocyanate (IPDI) or perhydro(diphenylmethane 2,4'- or 4,4'-diisocyanate) (HMDI), or a mixture thereof.

[0065] 4,4'-MDI, TDI, or IPDI are particularly preferred.

[0066] Suitable polyols are commercially available polyols or mixtures thereof, in particular, the following:

[0067] - Polyether polyols, in particular polyoxyalkylene diols and / or polyoxyalkylene triols, in particular polymer products of ethylene oxide or 1,2-propylene oxide or 1,2- or 2,3-butylene oxide or oxetane or tetrahydrofuran or mixtures thereof, wherein these are initiator molecules having two or three active hydrogen atoms, in particular water, ammonia or compounds having two or more OH groups or NH groups, e.g., ethane-1,2-diol, propane-1,2- or -1,3-diol, neopentyl glycol, diethylene glycol, triethylene glycol, isomer dipropylene glycol or tripropylene glycol, isomer butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonandiol, decanediol, undecanediol, cyclohexane-1,3- or Polymerization can be carried out with the help of initiator molecules such as -1,4-dimethanol, bisphenol A, hydrogenated bisphenol A, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol or aniline, or mixtures of the aforementioned compounds. Likewise, polyether polyols in which polymer particles are dispersed internally, particularly those having styrene / acrylonitrile (SAN) particles or polyurea or polyhydrazodicarbonamide (PHD) particles, are suitable.

[0068] A preferred polyether polyol is a polyoxypropylene diol or a polyoxypropylene triol, or a so-called ethylene oxide-terminated (EO-capped or EO-tipped) polyoxypropylene diol or triol. The latter is obtained, in particular, by further alkoxylating the polyoxypropylene diol or triol with ethylene oxide as a result of a polypropoxylation reaction, thereby having a primary hydroxyl group.

[0069] A desirable polyether polyol has a degree of unsaturation of less than 0.02 meq / g, particularly less than 0.01 meq / g.

[0070] - Polyester polyols, also known as oligoesterols, prepared by known processes, in particular by the polycondensation of hydroxycarboxylic acids or lactones or by the polycondensation of aliphatic and / or aromatic polycarboxylic acids and divalent or polyhydric alcohols. Dihydric alcohols, e.g., particularly ethane-1,2-diol, diethylene glycol, propane-1,2-diol, dipropylene glycol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, neopentyl glycol, glycerol, 1,1,1-trimethylolpropane, or mixtures of the aforementioned alcohols, and organic dicarboxylic acids or their anhydrides or esters, e.g., particularly succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexane-1,2-dicarboxylic acid, cyclohexane-1,3-dicarboxylic acid or -1,4-dicarboxylic acid, or mixtures of the aforementioned acids, or lactones, e.g., particularly Polyester diols from the reaction of a polyester polyol formed from ε-caprolactone are preferred. Polyester polyols formed from adipic acid, sebacic acid, or dodecanedicarboxylic acid with hexanediol or neopentyl glycol are particularly preferred.

[0071] - For example, a polycarbonate polyol that can be obtained by the reaction of the aforementioned alcohol—used to form a polyester polyol—with a dialkyl carbonate, a diaryl carbonate, or phosgene.

[0072] - A block copolymer having at least two different blocks having at least two OH groups and a polyether, polyester, and / or polycarbonate structure of the type described above, in particular a polyether polyester polyol.

[0073] - Polyacrylate or polymethacrylate polyol.

[0074] - Polyhydroxy-functional fats or oils, e.g., natural fats or oils, particularly castor oil; or polyols obtained by chemical modification of natural fats or oils—so-called oleochemical polyols—e.g., epoxy polyesters or epoxy polyethers obtained by epoxidation of unsaturated oils and subsequent ring opening with carboxylic acids or alcohols, or polyols obtained by hydroformylation and hydrogenation of unsaturated oils; or polyols obtained from natural fats and oils by decomposition processes such as alcoholic decomposition or ozone decomposition, and, for example, subsequent chemical linkage by transesterification or dimerization of the decomposition products or derivatives thus obtained. Suitable decomposition products of natural fats and oils are, in particular, fatty acids and fatty alcohols, and also fatty acid esters, in particular methyl esters (FAME), which can be derivatized into hydroxy fatty acid esters by, for example, hydroformylation and hydrogenation.

[0075] - Polyhydrocarbon polyols, also so-called oligohydrocarbonols, e.g., particularly polyhydroxy-functional polyolefins, polyisobutylene, polyisoprene; e.g., polyhydroxy-functional ethylene / propylene, ethylene / butylene, or ethylene / propylene / diene copolymers produced by such polymers; e.g., polyhydroxy-functional polymers of dienes, particularly 1,3-butadiene, which can also be produced from anionic polymerization; In particular, a diene, e.g., 1,3-butadiene, or a diene mixture, which can be produced from an epoxide or amino alcohol and a carboxyl-terminated acrylonitrile / butadiene copolymer, and a vinyl monomer, e.g., styrene, acrylonitrile, vinyl chloride, vinyl acetate, vinyl alcohol, isobutylene, or isoprene, in particular a polyhydroxy-functional copolymer of a polyhydroxy-functional acrylonitrile / butadiene copolymer (e.g., Hypro from Emerald Performance Materials).® Commercially available under the trade names CTBN or CTBNX or ETBN); or hydrogenated polyhydroxy-functional polymer or copolymer of a diene.

[0076] In addition, a mixture of polyols is particularly suitable.

[0077] Polyols and / or polyether triols having an OH value of at least 22 mg KOH / g are preferred.

[0078] In the case of preparing a polymer containing an isocyanate group, dihydric or polyfunctional alcohols, in particular ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2-methylpropane-1,3-diol, butane-1,2-diol, butane-1,3-diol, butane-1,4-diol, pentane-1,3-diol, pentane-1,5-diol, 3-methylpentane-1,5-diol, neopentyl glycol, dibromoneopentyl glycol, hexane-1,2-diol, hexane-1,6-diol, heptane-1,7-diol, octane-1,2-diol, octane-1,8-diol, 2-ethylhexane-1,3-diol, diethylene glycol, triethylene glycol, and dipropylene It is also possible to further use fractions of glycol, tripropylene glycol, cyclohexane-1,3-dimethanol or -1,4-dimethanol, ethoxylated bisphenol A, propoxylated bisphenol A, cyclohexanediol, hydrogenated bisphenol A, dimeric fatty acid alcohols, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol, pentaerythritol, sugar alcohols, e.g., particularly xylitol, sorbitol and mannitol, or sugars, e.g., particularly sucrose, or alkoxylated derivatives of the aforementioned alcohols or mixtures of the aforementioned alcohols.

[0079] Preferably, the moisture-curing polyurethane composition has a content of at least 25 weight%, preferably at least 40 weight%, and particularly at least 60 weight% of the polymer of the present invention, based on the total amount of the polymer containing isocyanate groups in the composition.

[0080] Preferably, the moisture-curing polyurethane composition further contains at least one branched component having an isocyanate group and an average of more than 2 NCO functional groups. Together with the polymer of the present invention, this enables good mechanical strength and thermal stability combined with good adhesion to plastic substrates.

[0081] Preferably, the branched component containing an isocyanate group is selected from the group consisting of oligomeric diisocyanates and branched polymers containing an isocyanate group.

[0082] Preferably, the branched component containing isocyanate groups has an average NCO functional group in the range of 2.2 to 4, particularly 2.3 to 3.5.

[0083] A desirable oligomeric diisocyanate is an HDI burette, e.g., Desmodur ® N 100 or N 3200 (Covestro product), Tolonate ® HDB or HDB-LV (Vencorex product) or Duranate ® 24A-100 (Product of Asahi Kasei); HDI isosacyanurate, e.g., Desmodur ® N 3300, N 3600, or N 3790 BA (all Covestro products), Tolonate ® HDT, HDT-LV, or HDT-LV2 (Vencorex product), Duranate ® TPA-100 or THA-100 (Asahi Kasei product) or Coronate ® HX (product of Nippon Polyurethane); HDI urethane diode, e.g., Desmodur ® N 3400 (Covestro product); HDI iminooxadiazine, e.g., Desmodur ®XP 2410 (Covestro product); HDI allophanates such as Desmodur ® VP LS 2102 (Covestro product); IPDI isosacyanurate, e.g., Desmodur ® Solution form as Z 4470 (Covestro product) or Vestanat ® Solid form as T1890 / 100 (Evonik product); TDI oligomer, e.g., Desmodur ® IL (Covestro product); or TDI / HDI-based mixed isosacyanurates, e.g., Desmodur ® HL (a product of Covestro), where "HDI" represents hexane 1,6-diisocyanate, "IPDI" represents isophorone diisocyanate, and "TDI" represents tolylene 2,4-diisocyanate or a mixture thereof with tolylene 2,6-diisocyanate.

[0084] Branched polymers containing isocyanate groups having average NCO functional groups in the range of 2.2 to 3, particularly 2.3 to 3, are preferred.

[0085] A particularly preferred branched polymer containing isocyanate groups is obtained from the removal of most unconverted monomeric diisocyanates following a reaction with 4,4'-MDI or IPDI, particularly 4,4'-MDI, having an NCO content in the range of 1 wt% to 2.5 wt% and a monomeric diisocyanate content of 0.3 wt% or less, and optionally an ethylene oxide-terminated polyoxypropylene triol having an average OH functional group in the range of 2.2 to 3 and an OH value in the range of 20 to 60 mg KOH / g, particularly 22 to 42 mg KOH / g, with at least a 4 / 1 NCO / OH ratio.

[0086] An additional particularly preferred branched polymer containing an isocyanate group is a conventionally produced polymer having an NCO content in the range of 1.2 wt% to 2.5 wt%, obtained by reacting at least one monomeric diisocyanate with at least one polyoxypropylene triol and optionally at least one polyoxypropylene diol (wherein the triol and diol optionally comprise a fraction of a 1,2-ethyleneoxy group) in an NCO / OH ratio in the range of 1.5 / 1 to 2.2 / 1. For this purpose, a preferred monomeric diisocyanate is 4,4'-MDI, TDI, or IPDI.

[0087] The moisture-curing polyurethane composition may contain at least one additional linear polymer containing isocyanate groups in addition to the polymer of the present invention. Particularly preferred for this purpose is a polymer having an NCO content in the range of 1.6 wt% to 2.4 wt%, in particular 1.6 wt% to 2.1 wt% and a monomeric diisocyanate content of 0.3 wt% or less, obtained from the removal of most unconverted 4,4'-MDI as described above, following the reaction of 4,4'-MDI with an optionally ethylene oxide-terminated polyoxypropylene diol having an OH value in the range of 23 to 38 mg KOH / g, particularly 25 to 32 mg KOH / g, in a 4 / 1 NCO / OH ratio.

[0088] Preferably, the moisture-curing polyurethane composition contains a linear polymer and a branched isocyanate group-containing component in a weight ratio ranging from 60 / 40 to 99 / 1, preferably from 70 / 30 to 98 / 2. Within this range, there is a particularly attractive combination of good adhesion to plastic substrates and favorable mechanical properties.

[0089] When a moisture-curing polyurethane composition contains at least one oligomeric diisocyanate, the weight ratio between the linear polymer and the oligomeric diisocyanate is preferably in the range of 90 / 10 to 99.5 / 0.5, preferably 95 / 5 to 99 / 1, and particularly 95 / 5 to 98 / 2.

[0090] When a moisture-curing polyurethane composition contains at least one branched polymer containing an isocyanate group, the weight ratio between the linear polymer and the branched polymer is preferably in the range of 60 / 40 to 95 / 5, particularly 70 / 30 to 90 / 10.

[0091] In one embodiment of the present invention, the moisture-curing polyurethane composition further comprises at least one blocked amine.

[0092] Suitable blocked amines preferably have at least one aldimino group or oxazolidinino group. Upon contact with moisture, they hydrolyze to release the amino group and react with available isocyanate groups, which can promote rapid, bubble-free curing, particularly non-stick surfaces and / or particularly good mechanical properties.

[0093] Preferred oxazolidins are bis-oxazolidins, in particular isobutyraldehyde, benzaldehyde or substituted benzaldehyde, in particular those derived from benzaldehydes substituted at the para position with an optionally branched alkyl group having 10 to 14 carbon atoms.

[0094] Bisoxazolidine from the reaction of OH-functional monooxazolidine with diisocyanate, particularly hexamethylene 1,6-diisocyanate, is preferred. Suitable monooxazolidine is obtained particularly from the reaction of diethanolamine with an aldehyde with the removal of water release.

[0095] Suitable aldimins are, in particular, divalent or trialdimins from the reaction of commercial primary divalent or triamines with non-enolable aldehydes. These are aldehydes that do not have a hydrogen atom at the alpha position for the carbon atom of the aldehyde group.

[0096] Particularly preferred blocked amines are N,N'-bis(2,2-dimethyl-3-lauroyloxypropylidene)hexylene-1,6-diamine, N,N'-bis(2,2-dimethyl-3-acetoxypropylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine, N,N'-bis(2,2-dimethyl-3-lauroyloxypropylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine, N,N'-bis(benzylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine, N,N'-bis(4-C 10-14 -alkylbenzylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine, average molecular weight M in the range of 450 to 750 g / mol n N,N'-bis(2,2-dimethyl-3-acetoxypropylidene)polyoxypropylenediamine having an average molecular weight M in the range of 750 to 1,050 g / mol n N,N'-bis(2,2-dimethyl-3-lauroyloxypropylidene)polyoxypropylenediamine having an average molecular weight M in the range of 380 to 680 g / mol n N,N'-bis(benzylidene)polyoxypropylenediamine having an average molecular weight M in the range of 680 to 1,100 g / mol n N,N'-bis(4-C) with 10-14 -alkylbenzylidene)polyoxypropylenediamine, average molecular weight M in the range of 730 to 880 g / mol n N,N',N''-tris(2,2-dimethyl-3-acetoxypropylidene)polyoxypropylene lyamine having an average molecular weight M in the range of 1,150 to 1,300 g / mol n It is selected from the group consisting of N,N',N''-tris(2,2-dimethyl-3-lauroyloxypropylidene)polyoxypropylene lyamines having

[0097] The moisture-curing polyurethane composition preferably further comprises at least one additional component selected from catalysts, fillers, plasticizers, and stabilizers.

[0098] Suitable catalysts are catalysts for promoting the reaction of isocyanate groups, in particular organotin (IV) compounds, e.g., particularly dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, dibutyltin diacetylacetonate, dimethyltin dilaurate, dioxbutyltin diacetate, dioxbutyltin dilaurate or dioxbutyltin diacetylacetonate, bismuth (III) or zirconium (IV) and complexes with ligands selected from alkoxides, carboxylates, 1,3-diketonates, oxynates, 1,3-ketoesterates, and 1,3-ketoamidates, or compounds containing tertiary amino groups, e.g., particularly 2,2'-dimolpolynodiethyl ether (DMDEE).

[0099] When a moisture-curing polyurethane composition contains a blocked amine, a suitable catalyst is also a catalyst for the hydrolysis of the blocked amino group, in particular an organic acid, in particular an aromatic carboxylic acid, e.g., benzoic acid, 2-nitrobenzoic acid, or salicylic acid.

[0100] Combinations of different catalysts are also particularly suitable.

[0101] Suitable fillers are ground or precipitated calcium carbonate selectively coated with fatty acids, particularly stearates, barite, quartz powder, silica sand, dolomite, wollastonite, calcined kaolin, sheet silicates, e.g., mica or talc, zeolite, aluminum hydroxide, magnesium hydroxide, silica including finely ground silica from a pyrolysis process, cement, gypsum, fly ash, industrially produced carbon black, graphite, metal powders of, e.g., aluminum, copper, iron, silver or steel, PVC powder, or hollow beads.

[0102] Calcium carbonate selectively coated with fatty acids, particularly stearates, calcined kaolin, or industrially produced carbon black are preferred.

[0103] Suitable plasticizers are particularly carboxylic acid esters, e.g., phthalates, particularly diisononyl phthalate (DINP), diisodecyl phthalate (DIDP) or di(2-propylheptyl) phthalate (DPHP), hydrogenated phthalate or cyclohexane-1,2-dicarboxylate esters, particularly hydrogenated diisononyl phthalate or diisononyl cyclohexane-1,2-dicarboxylate (DINCH), terephthalates, particularly bis(2-ethylhexyl) terephthalate (DOTP) or diisononyl terephthalate (DINT), hydrogenated terephthalate or cyclohexane-1,4-dicarboxylate, particularly hydrogenated bis(2-ethylhexyl) terephthalate or bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate, or hydrogenated diisononyl terephthalate or It is a plasticizer having a structure of diisononyl cyclohexane-1,4-dicarboxylate, isophthalate, trimellitate, adipate, particularly dioctyl adipate, azelate, sebacate, benzoate, glycol ether, glycol ester, polyether, particularly polypropylene oxide monool, diol or triol, organic phosphoric acid or sulfonic acid ester, polybutene, polyisobutene or natural fat or oil, particularly epoxided soybean oil or linseed oil, having blocked hydroxyl groups particularly in the form of acetate groups.

[0104] A desirable plasticizer is a plasticizer having a phthalate, hydrogenated phthalate, adipate, or polyether structure.

[0105] Suitable stabilizers are stabilizers, in particular, for oxidation, heat, light, or UV radiation. The composition preferably includes at least one UV stabilizer.

[0106] The moisture-curing polyurethane composition may contain additional additives, in particular, the following:

[0107] - Inorganic or organic pigments, especially titanium dioxide, chromium oxide, or iron oxide;

[0108] - Fibers, particularly glass fibers, carbon fibers, metal fibers, ceramic fibers, polymer fibers, e.g., polyamide fibers or polyethylene fibers, or natural fibers, e.g., wool, cellulose, hemp, or sisal;

[0109] - Nanofillers, e.g., graphene or carbon nanotubes;

[0110] - Dye;

[0111] - Drying agents, particularly molecular sieve powders, calcium oxide, highly reactive isocyanates, e.g., p-tosyl isocyanate, Incozol ® Monooxazolidine such as 2 (Incorez product), or orthoformic acid ester;

[0112] - Adhesion promoters, particularly organoalkoxysilanes, particularly epoxysilanes, e.g., particularly 3-glycidoxypropyltrimethoxysilane or 3-glycidoxypropyltriethoxysilane, (meth)acrylosilane, anhydridosilane, carbamatesilane, alkylsilane or iminosilane, or oligomeric forms of these silanes, or titanates;

[0113] - Additional catalyst to accelerate the reaction of the isocyanate group;

[0114] - Rheology modifiers, particularly thickeners, particularly sheet silicates, e.g., bentonite, derivatives of castor oil, hydrogenated castor oil, polyamides, polyamide waxes, polyurethanes, urea compounds, fuming silica, cellulose ethers, or hydrophobically modified polyoxyethylene;

[0115] - Solvents, particularly acetone, methyl acetate, tert-butyl acetate, 1-methoxy-2-propyl acetate, ethyl 3-ethoxypropionate, diisopropyl ether, diethylene glycol diethyl ether, ethylene glycol diethyl ether, ethylene glycol monobutyl ether, ethylene glycol mono-2-ethylhexyl ether, propylal, butylal, 2-ethylhexylal, dioxolane, glycerol formal, or acetals such as 2,5,7,10-tetraoxaudecane (TOU), toluene, xylene, heptane, octane, naphtha, white oil, petroleum ether, or gasoline, particularly Solveso™ grades (Exxon products), and propylene carbonate, dimethyl carbonate, butyrolactone, N-methylpyrrolidone, N-ethylpyrrolidone, p-chlorobenzotrifluoride or benzotrifluoride;

[0116] - Natural resins, fats, or oils, e.g., rosin, shellac, linseed oil, castor oil, or soybean oil;

[0117] - A homopolymer or copolymer of a particularly unsaturated monomer from the group comprising non-reactive polymers, in particular ethylene, propylene, butylene, isobutylene, isoprene, vinyl acetate or alkyl (meth)acrylates, in particular polyethylene (PE), polypropylene (PP), polyisobutylene, ethylene-vinyl acetate copolymer (EVA) or atactic poly-α-olefin (APAO);

[0118] - Flame-retardant materials, in particular aluminum hydroxide or magnesium hydroxide or organic phosphate esters, which are the previously mentioned fillers;

[0119] - Additives, in particular wetting agents, leveling agents, defoaming agents, degassing agents, or biocides;

[0120] Or additional materials commonly used in moisture-curing polyurethane compositions.

[0121] It may be recommended to chemically or physically dry the specified material before mixing it into the composition.

[0122] When the polymer of the present invention containing isocyanate groups is mixed with additional components of the composition, particularly fillers, the content of monomeric diisocyanate may be further reduced by reaction with present moisture.

[0123] The moisture-curing polyurethane composition preferably contains the following:

[0124] - A polymer containing isocyanate groups in an amount of 30% to 70% by weight, wherein 10% to 70% by weight is the polymer of the present invention,

[0125] - 20% to 60% by weight of filler,

[0126] - 0 weight% to 25 weight%, particularly 0 weight% to 10 weight% of a plasticizer,

[0127] and optionally additional components, in particular oligomeric diisocyanates, blocked amines, or catalysts.

[0128] The moisture-curing polyurethane composition has high strength combined with high elongation after curing.

[0129] The tensile strength determined as described in the examples is preferably at least 1.5 MPa, more preferably at least 2 MPa, and particularly at least 2.5 MPa.

[0130] The elastic modulus in the range of 0.05% to 5% elongation determined as described in the examples is 2 to 20 MPa, particularly in the range of 3 to 15 MPa.

[0131] The elongation at break determined as described in the examples is preferably at least 300%, particularly at least 500%.

[0132] Moisture-curing polyurethane compositions are manufactured particularly by excluding moisture and stored at ambient temperature in moisture-tight containers. Suitable moisture-tight containers are made of metal and / or plastic, particularly optionally coated, and are drums, transfer boxes, hobbocks, buckets, canisters, cans, bags, tubular bags, cartridges, or tubes.

[0133] The moisture-curing polyurethane composition may be in the form of a one-component composition or a multi-component, particularly a two-component composition.

[0134] A composition referred to as a "one-component" composition is one in which all components of the composition are in the same container and are inherently storage stable.

[0135] A composition referred to as a "2-component" composition is a composition consisting of two different components that are stored in separate containers and are not mixed with anything else until or during the application of the composition.

[0136] The moisture-curing polyurethane composition is preferably a one-component composition. Given proper packaging and storage, it is typically storage stable for several months to over one year.

[0137] When a moisture-curing polyurethane composition is applied, a curing process is initiated. This results in a cured composition.

[0138] In the case of a 1-component composition, it is applied as is and then begins to cure under the influence of moisture or water. To promote curing, an accelerator component containing or releasing water and / or a catalyst may be mixed into the composition at the time of application or may be brought into contact with such an accelerator component after the composition has been applied.

[0139] During the curing process, isocyanate groups react with each other under the influence of moisture. If the moisture-curing polyurethane composition contains blocked amines, the isocyanate groups further react with the blocked amino groups when hydrolyzed. The total of these reactions of the isocyanate groups that result in the curing of the composition is also referred to as crosslinking.

[0140] The moisture required for the curing of the moisture-curing polyurethane composition is preferably introduced into the composition through diffusion from the air (atmospheric moisture). In this process, a hard layer ("skin") of the cured composition is formed on the surface of the composition in contact with the air. Curing continues in a diffusion direction from the outside inward, and the skin becomes progressively thicker and ultimately encompasses the entire applied composition. Moisture may also reach the composition additionally or entirely from one or more substrate(s) to which the composition is applied, and / or may originate from accelerator components mixed into the composition at application or coming into contact with the composition after application, for example, by painting or spraying.

[0141] The moisture-curing polyurethane composition is preferably applied at ambient temperatures, particularly within the range of about -10 to 50°C, preferably -5 to 45°C, particularly within the range of 0 to 40°C.

[0142] The moisture-curing polyurethane composition is preferably cured at ambient temperature as well.

[0143] Moisture-curing polyurethane compositions have a long processing time (open time) and fast curing.

[0144] When a moisture-curing polyurethane composition contains blocked amines, the aldehyde used to block the amino groups is released during the crosslinking process. If this is mostly non-volatile, it will remain mostly in the cured composition and act as a plasticizer.

[0145] It is preferred to use a moisture-curing polyurethane composition as an elastic adhesive, elastic sealant, or elastic coating.

[0146] Moisture-curing polyurethane compositions as adhesives and / or sealants are particularly suitable for bonding and sealing applications, especially in the construction and manufacturing industries, or in automotive structures, particularly for floor bonding, assembly, bonding of installable parts, module bonding, plate glass bonding, joint sealing, body sealing, seam sealing, or cavity sealing.

[0147] Elastic joining in automotive structures is particularly such as attaching plastic covers, decorative strips, flanges, fenders, cabs, or other installable parts to the painted chassis of an automobile, or joining windows to the car body, where the automobile is specifically an automobile, truck, bus, railway vehicle, or ship.

[0148] Moisture-curing polyurethane compositions are particularly suitable as sealants for elastic sealing of all kinds of joints, seams, or particularly joint cavities in construction, expansion joints or connecting joints between structural parts, particularly parts made of plastic, for example, floor joints in civil engineering. Sealants with flexible properties and high cooling flexibility are particularly suitable for sealing expansion joints in building structures.

[0149] As a coating, moisture-curing polyurethane compositions are particularly suitable for balconies, terraces, roofs, especially flat or slightly sloped roof areas or rooftop gardens, particularly in fields made of plastic materials, or for building interiors under tiles or ceramic plates in wet rooms or kitchens, or for the protection and / or sealing of building structures or parts thereof in collection fans, conduits, shafts, silos, tanks, or wastewater treatment systems.

[0150] In addition, it can be used for repair purposes, for example, as a sealant or coating agent for leaking roof membranes or floor coverings that are no longer suitable for the purpose, or as a repair compound for highly reactive spray sealing.

[0151] Moisture-curing polyurethane compositions can be formulated to have a paste consistency having structurally viscous properties. This type of composition is applied by a suitable device from a commercial cartridge, vat, or hopbox, such as in the form of beads that may essentially have a round or triangular cross-sectional area.

[0152] Water-curing polyurethane compositions can also be formulated to be fluid, “self-leveling” or only slightly thixotropic, and pourable for application. As a coating, for example, it can then be spread evenly to a desired layer thickness by means of a roller, slide bar, notched applicator, or trowel. In one operation, a layer thickness typically ranging from 0.5 to 3 mm, particularly from 1 to 2.5 mm, is applied.

[0153] It is preferred to use a moisture-curable polyurethane composition as an elastic adhesive, elastic sealant, or elastic coating for bonding, sealing, or coating at least one plastic substrate.

[0154] Suitable plastic substrates are particularly rigid and flexible PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resin, phenolic resin, PUR, POM, TPO, PE, PP, EPM, EPDM, or polycarbonate and additional plastics, e.g., particularly ABS and / or SAN (wherein these plastics may be treated in an untreated or surface-treated form, e.g., by plasma, corona, or flame) and fiber-reinforced plastics, e.g., particularly carbon fiber reinforced plastic (CFRP), glass fiber reinforced plastic (GFRP), or sheet molding compound (SMC).

[0155] Preferably, the plastic substrate is selected from the group consisting of rigid PVC, flexible PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resin, phenolic resin, PUR, POM, TPO, PE, PP, EPM, EPDM, and a combination of polycarbonate and additional plastics, e.g., particularly ABS and / or SAN.

[0156] Among these, rigid PVC, polycarbonate, polycarbonate and ABS and / or SAN blends, PMMA or ABS, and especially polycarbonate or polycarbonate blends are preferred. These plastics are particularly important for good adhesion without complex pretreatment and must be bonded frequently.

[0157] Suitable additional substrates that can be bonded, sealed, or coated with a moisture-curing polyurethane composition are particularly as follows:

[0158] - Metals or alloys, e.g., aluminum, copper, iron, steel, non-ferrous metals including surface-finished metals, or alloys such as galvanized or chrome-plated metals;

[0159] - Coated or painted substrates, in particular painted tiles, coated concrete, powder-coated metal or alloy or painted metal sheets;

[0160] - Paints or varnishes, especially automotive finishes;

[0161] - Glass, glass ceramics, concrete, mortar, cement screed, fiber cement, especially fiber cement boards, bricks, tiles, gypsum, especially gypsum boards or anhydride screed, natural stone such as granite or marble;

[0162] - Repair or smoothing compounds based on PCC (polymer-modified cement mortar) or ECC (epoxy resin-modified cement mortar);

[0163] - Asphalt or bitumen;

[0164] - Leather, textiles, paper, wood, wood materials bonded with resins such as phenolic, melamine, or epoxy resins, resin / textile composites or additional materials, so-called polymer composites;

[0165] - Insulating foams, especially made of EPS, XPS, PUR, PIR, rock wool, glass wool, or foamed glass.

[0166] If necessary, the substrate may be pretreated prior to application, particularly by physical and / or chemical cleaning methods or by the application of an activator or primer.

[0167] It is possible to bond and / or seal two identical or two different materials.

[0168] A moisture-curing polyurethane composition is used in an adhesive or sealing method, preferably comprising the following steps:

[0169] (i) the described moisture-curing polyurethane composition,

[0170] - Apply to the first substrate and bring into contact with the second substrate within the opening time of the composition, or

[0171] - Apply to the first and second substrates, and bond the two substrates within the opening time of the composition, or

[0172] - Step applied between two materials,

[0173] (ii) A step of curing the composition by contact with moisture.

[0174] The moisture-curing polyurethane composition is also preferably used in a coating or sealing method comprising the following steps:

[0175] (i) a step of applying the described moisture-curing polyurethane composition to a substrate,

[0176] (ii) A step of curing the composition by contact with moisture.

[0177] In these methods, preferably at least one substrate is a plastic substrate as described above.

[0178] The application and curing of a moisture-curing polyurethane composition provides an article bonded, sealed, or coated with the composition. This article may be a building structure or part thereof, particularly a building structure, roof, stairs, or facade in civil engineering above or below ground, or an industrial or consumer product, particularly a window, lamp, traffic signal, white goods, or transport mode, e.g., automobile, bus, caravan, truck, railway vehicle, ship, aircraft, or helicopter, or an installable part thereof, e.g., a window, panoramic roof, or lamp housing made of organic glass.

[0179] The present invention further provides a cured composition obtained from a moisture-curing polyurethane composition after contact with moisture.

[0180] The present invention further provides an adhesive comprising at least one plastic substrate and a composition that is cured by contact with moisture as described above.

[0181] Examples

[0182] Work examples are presented below with the intent to further explain the invention described herein. The invention is, of course, not limited to the work examples described herein.

[0183] "Standard climate conditions" ("SCC") refer to a temperature of 23±1℃ and a relative air humidity of 50±5%.

[0184] Unless otherwise stated, the chemicals used were purchased from Sigma-Aldrich.

[0185] viscosity Rheotec RC30 cone-plate viscometer equipped with a thermostat (cone diameter 25 mm, cone angle 1°, cone tip-to-plate distance 0.05 mm, shear rate 10 s -1 It was measured as ).

[0186] Monomeric diisocyanate content It was determined by HPLC (detection via photodiode array; 0.04 M sodium acetate / acetonite as mobile phase) after pre-derivation with N-propyl-4-nitrobenzylamine.

[0187] Polyols used:

[0188]

[0189] Monomeric diisocyanates used:

[0190]

[0191] Preparation of a polymer containing isocyanate groups:

[0192] Polymer L1 (linear):

[0193] Acclaim of 757.7g (0.19 eq OH) ® 8200N and 242.3g (1.9 eq NCO) of Desmodur ®44 MC L was reacted at 80°C by a known method to provide a polymer having an NCO content of 7.2 wt%, a viscosity of 6.8 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of about 20 wt%.

[0194] Subsequently, volatile components, particularly most monomeric diphenylmethane 4,4'-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180°C, pressure 0.1 to 0.005 mbar, condensation temperature 47°C). The linear polymer thus obtained had a polymer having an NCO content of 1.0 wt%, a viscosity of 25.0 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of 0.06 wt%.

[0195] Polymer L2 (linear):

[0196] Acclaim of 812.0 g (0.15 eq OH) ® Desmodur at 12200N and 188.0g (1.5 eq NCO) ® 44 MC L was reacted at 80°C by a known method to provide a polymer having an NCO content of 5.6 wt%, a viscosity of 13.9 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of about 14 wt%.

[0197] Subsequently, volatile components, particularly most monomeric diphenylmethane 4,4'-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180°C, pressure 0.1 to 0.005 mbar, condensation temperature 47°C). The linear polymer thus obtained had an NCO content of 0.7 wt%, a viscosity of 29.4 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of 0.04 wt%.

[0198] Polymer Ref-1 (Linear, Comparison):

[0199] 727.0g of Acclaim ® 4200 and 273.0g of Desmodur ® 44 MC L was reacted at 80°C by a known method to provide a polymer having an NCO content of 7.4 wt%, a viscosity of 5.2 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of about 17 wt%.

[0200] Subsequently, volatile components, particularly most monomeric diphenylmethane 4,4'-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180°C, pressure 0.1 to 0.005 mbar, condensation temperature 47°C). The linear polymer thus obtained had an NCO content of 1.8 wt%, a viscosity of 13.3 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of 0.08 wt%.

[0201] Polymer C-1 (branched):

[0202] 725.0g of Desmophen ® 5031 BT and 275g of Desmodur ® 44 MC L was reacted at 80°C by a known method to provide a polymer having an NCO content of 7.6 wt%, a viscosity of 6.5 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of about 20 wt%.

[0203] Subsequently, volatile components, particularly most monomeric diphenylmethane 4,4'-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180°C, pressure 0.1 to 0.005 mbar, condensation temperature 47°C). The linear polymer thus obtained had an NCO content of 1.7 wt%, a viscosity of 19 Pa·s at 20°C, and a monomeric diphenylmethane 4,4'-diisocyanate content of 0.04 wt%.

[0204] Moisture-curing polyurethane composition:

[0205] Compositions Z1 to Z7:

[0206] For each composition, the ingredients specified in Table 1 were mixed in the specified amounts (parts by weight) using a centrifugal mixer (SpeedMixer™ DAC 150, FlackTek Inc.) at 3,000 rpm for 1 minute while excluding moisture, and stored while excluding moisture. Each composition was tested as follows:

[0207] Shore A Hardness was determined according to DIN 53505 for test specimens hardened for 14 days under standard climatic conditions.

[0208] To determine mechanical properties, the composition was applied to a silicone-coated release liner to provide a film with a thickness of 2 mm, which was stored for 14 days under standard climatic conditions, and several dumbbells with a length of 75 mm, a bar length of 30 mm, and a bar width of 4 mm were punched out of the film and these were prepared according to DIN EN 53504 tensile strength (Breaking force), Elongation at break and 5% Elastic modulus Tests were performed at a deformation speed of 200 mm / min for (0.5 to 5% elongation).

[0209] Regarding plastic substrates AdhesionThe adhesion strength was determined by applying four parallel bead-shaped compositions, each approximately 10 mm wide, 5 mm high, and 15 mm long, to each substrate and curing them for 7 days under standard climatic conditions. Subsequently, the adhesion strength of the cured compositions was first tested by cutting the first bead at the narrow end just above the bonding surface, grasping the severed end of the bead with rounded tweezers, and attempting to detach the bead from the substrate. Next, the bead was cut again under the substrate, the severed portion was wrapped with rounded tweezers, and an attempt was made to detach the bead from the substrate again. In this manner, the entire bead was severed from the substrate by pulling. Subsequently, the adhesion strength was evaluated from the failure profile, and in Table 1, " 7d SCC " reported below. Subsequently, several test specimens were immersed in deionized water for 7 days and stored, then stored under standard climatic conditions for 2 hours, then the second bead was pulled off from the substrate with rounded tweezers and the adhesion was evaluated from the failure profile, and in Table 1 " 7d H 2 O" It was reported below. Subsequently, the specimens were stored in an air-circulating oven at 80°C for 24 hours, then stored under standard climate conditions for 2 hours, and then the adhesion was tested as described for the third bead, evaluated from the failure profile, and in Table 1 " 1d 80℃" Reported below. Finally, after storing the test specimens at 70°C and 100% relative humidity for 7 days, they were stored under standard climatic conditions for 2 hours, and then the fourth bead was tested for adhesion as described; the adhesion was evaluated from the failure profile, and in Table 1 " 7d 70℃ / 100%RH" It was reported below.

[0210] The plastic material used was the following plastic sheet (300×200×2㎜):

[0211] PMMA : Plexiglas ®XT 0A000(Evonik product)

[0212] PC : Makrolon ® GP clear 099 (uncoated polycarbonate, Covestro product)

[0213] ABS : Metzoplast ABS / G (Product of Metzeler Plastics GmbH)

[0214] PVC : ® ES( Kunststoffe product)

[0215] Adhesion strength was evaluated under the following scale:

[0216] 100 indicates more than 95% cohesive failure and means very good adhesion.

[0217] 40 indicates 40% cohesive failure and means moderate adhesion.

[0218] 5 indicates 5% cohesive failure and means inadequate adhesion.

[0219] 0 indicates 0% cohesive failure (100% adhesion failure) and means poor adhesion.

[0220] The results are reported in Table 1.

[0221] Comparative example is (Ref.) It is identified as.

[0222]

[0223]

Claims

Claim 1 A linear polymer having an NCO content in the range of 0.3 wt% to 1.5 wt% and a monomeric diisocyanate content of 0.5 wt% or less and containing isocyanate groups, characterized by being obtained by removing the monomeric aromatic diisocyanate by a separation method following a reaction of at least one monomeric aromatic diisocyanate with a polyether diol having an OH number in the range of 5 to 21 mg KOH / g at an NCO / OH ratio of at least 5 / 1. Claim 2 A linear polymer according to claim 1, characterized in that the monomeric aromatic diisocyanate is diphenylmethane 4,4'-diisocyanate. Claim 3 A linear polymer according to claim 1, wherein the polyether diol contains 80% to 100% by weight of 1,2-propylene oxygen groups and 0% to 20% by weight of 1,2-ethylene oxygen groups. Claim 4 A linear polymer according to claim 1, wherein the polyether diol has an OH value in the range of 6 to 19 mg KOH / g and an average OH functional group of at least 1.

9. Claim 5 A linear polymer according to claim 1, characterized in that an excess amount of monomeric diisocyanate is removed by a distillation method. Claim 6 A linear polymer according to claim 1, characterized by having an NCO content in the range of 0.5 weight% to 1.3 weight% and a monomeric diisocyanate content of 0.3 weight% or less. Claim 7 A linear polymer according to claim 1, characterized in that the NCO content is at least 90% of the theoretical NCO content calculated from the addition of 1 mole of monomeric diisocyanate per 1 mole of OH groups in the polyether diol. Claim 8 A moisture-curing polyurethane composition having a monomeric diisocyanate content of less than 0.1 weight%, comprising a polymer according to any one of claims 1 to 7. Claim 9 A moisture-curing polyurethane composition according to claim 8, characterized by having a polymer content according to any one of claims 1 to 7 of 5% to 80% by weight based on the total composition. Claim 10 A moisture-curing polyurethane composition according to claim 8, characterized by having a polymer content of at least 25 weight% according to any one of claims 1 to 7, based on the total amount of the polymer containing isocyanate groups in the composition. Claim 11 A moisture-curing polyurethane composition according to claim 8, further comprising at least one component containing an isocyanate group and having an average of more than 2 NCO functional groups. Claim 12 In claim 8, the composition is a moisture-curing polyurethane composition used as an elastic adhesive, elastic sealant, or elastic coating agent for bonding, sealing, or coating at least one plastic substrate. Claim 13 A moisture-curing polyurethane composition according to claim 12, wherein the plastic substrate is selected from the group consisting of rigid PVC, flexible PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resin, phenolic resin, PUR, POM, TPO, PE, PP, EPM, EPDM, and a mixture of polycarbonate and ABS and / or SAN. Claim 14 A cured product obtained after contacting a moisture-curing polyurethane composition according to claim 8 with moisture. Claim 15 A bonded composite comprising at least one plastic substrate and a polyurethane composition according to claim 8 that is cured by contact with moisture.

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