Polymer having an aldehyde group

Abstract

The present invention relates to a nonionic aldehyde-functional polymer having end groups of formula (I) and an average aldehyde group content of 0.15 to 1.2 milliequivalents / g. This polymer is suitable for crosslinking, at ambient temperature, more specifically compounds having highly reactive groups such as cyanoacetate groups, acetoacetate groups or malonate groups. It enables elastic products having particularly long processing times with rapid curing and particularly high tensile strength and tear propagation resistance with high extensibility. It is therefore suitable as a component of adhesives, sealants or coatings that are particularly robust and durable, have low sensitivity to moisture and blistering, have particularly good processability and contain little or no toxic raw materials.

Description

Technical Field

[0001] The present invention relates to polymers having an aldehyde group and their use for the curing of compounds having reactive groups such as cyanoacetate, acetoacetate or malonate groups, and to room temperature curable adhesives, sealants or coatings.

Background Art

[0002] Highly reactive polymer compositions that are curable at room temperature and can be used as adhesives, sealants or coatings having elastic properties are known. Polyurethane systems that cure by the reaction of isocyanate groups with polyols and / or water and form particularly highly elastic polymers are widely used. However, they are sensitive to the formation of air bubbles as a result of excess water during the curing process, and the polyisocyanates used for this purpose are usually toxic compounds. Silane-functional polymers (SMP / STP) and silicone-based highly reactive polymer compositions are also widely used. During their curing process, alcohols, particularly methanol or ethanol, or oximes are released, which are toxic, cause VOC emissions, and furthermore usually contain large amounts of low molecular weight silanes that are likewise harmful to health. Aqueous polymer systems based on acrylate dispersions or polyurethane dispersions are also known. These cure by evaporation and adhesion of water and mostly do not contain chemically reactive groups. However, they can only be used for relatively thin layers and only between open pore substrates, the curing rate is highly dependent on the ambient humidity, and they have a high shrinkage. After curing, the water sensitivity is increased due to the surfactants present, which are required for the production and stability of the dispersion, and this can lead to a reduction in durability, especially in outdoor applications.

Summary of the Invention

Problems to be Solved by the Invention

[0003] It is an object of the present invention to provide a functional polymer that can be crosslinked together with a compound having a suitable reactive group and enables a room temperature curable composition having elastic properties that overcome the drawbacks of the prior art.

Means for Solving the Problems

[0004] Surprisingly, this object is achieved by a nonionic aldehyde-functional polymer as described in claim 1. The aldehyde-functional polymer of the present invention having terminal groups of formula (I) is not sensitive to moisture and bubble formation, has low toxicological concerns, does not require hazard labels, and can be handled without special precautions. The polymers of the present invention are particularly suitable for crosslinking compounds having reactive groups such as cyanoacetate groups, 1,3-ketoester groups or malonate groups, and such polymer systems have good processability without any need for organic solvents for dissolution or dilution, or water for emulsification or dispersion of the components. It surprisingly has very good controllability of the curing rate with conventional catalysts, especially non-metallic bases such as tertiary amines, amidines or guanidines, and cures rapidly and completely under ambient conditions regardless of humidity without causing emissions. The curing results in a non-tacky elastic polymer having high strength and stretchability, as well as good stability to heat and water.

[0005] The polymers of the present invention enable particularly high-quality elastic adhesives, sealants or coatings that overcome the drawbacks of the prior art with respect to toxic raw materials, sensitivity and stability to moisture, and robustness after curing.

[0006] A further aspect of the present invention is the subject matter of further independent claims. Particularly preferred embodiments of the present invention are the subject matter of the dependent claims.

Embodiments for Carrying Out the Invention

[0007] The present invention relates to formula (I)

Chemical formula

[0008] A "nonionic" polymer refers to a polymer having an ionic group content of less than 0.05% by weight, especially less than 0.01% by weight, based on the polymer, and the ionic group is especially selected from carboxylate groups, ammonium groups and sulfonate groups.

[0009] "Room temperature" refers to a temperature of 23 °C.

[0010] In each case, the dotted line in the formula in this document represents the bond between the substituent and the corresponding remainder of the molecule.

[0011] "Molecular weight" refers to the molar mass of a molecule (in grams per molecule).

[0012] "Number average molecular weight" refers to the number average molecular weight (M n ) of a polydisperse mixture of oligomer molecules or polymer molecules. It is measured by gel permeation chromatography (GPC) relative to polystyrene as a standard.

[0013] Substance names starting with "poly", such as polyol, polyisocyanate, polycyanoacetate or polyacetoacetate, refer to substances formally containing two or more functional groups appearing in their names per molecule.

[0014] A "storage-stable" substance or composition is one that can be stored at room temperature in a suitable container for a long period of time, typically at least 3 months and up to 6 months or more, without this storage causing any change in any of its application or use properties with respect to its use.

[0015] All industry standards and specifications mentioned in this document relate to the valid version as of the date of the initial application.

[0016] Percent by weight (% w / w) refers to the proportion by mass of the components of a composition or molecule, based on the total composition or total molecule, unless otherwise specified. The terms "mass" and "weight" are used interchangeably in this document.

[0017] The aldehyde-functional polymer preferably has an average molecular weight M in the range of 1,500 to 20,000 g / mol, preferably 2,500 to 15,000 g / mol, particularly 3,500 to 8,000 g / mol, as measured by gel permeation chromatography (GPC) relative to polystyrene as the standard. n having.

[0018] Preferably, the average aldehyde functionality of the aldehyde-functional polymer is 1.8 to 4, preferably 2.0 to 3, particularly 2.2 to 3.0.

[0019] Preferably, the aldehyde-functional polymer contains less than 20% by weight, particularly less than 15% by weight, of oxyalkylene units based on the total polymer. Such polymers are particularly stable to moisture.

[0020] Preferably, in formula (I), R is a linear or branched alkylene group, a cycloalkylene group, an arylalkylene group or an aryl group, which may also contain oxygen and / or nitrogen atoms.

[0021] In particular, the R group is methylene, propane-1,2-diyl, 2-methylpropane-1,2-diyl, butane-1,4-diyl, 2-oxabutane-1,4-diyl, 3-oxapentane-1,5-diyl,

Chemical formula

[0022] Among these,

Chemical formula

[0023]

Chemical formula

[0024] Preferably, D in formula (I) is a divalent group of hexane-1,6-diamine, 2,2(4),4-trimethylhexane-1,6-diamine, 1-methyl-2,4(6)-diaminocyclohexane, isophoronediamine, 4,4'-diaminodicyclohexylmethane, diphenylmethane-4(2),4'-diamine or toluene-2,4(6)-diamine after removal of two amino groups.

[0025] More preferably, D is a divalent group of hexane-1,6-diamine or isophoronediamine after removal of two amino groups, especially the group of isophoronediamine after removal of two amino groups. Such aldehyde-functional polymers are particularly low in viscosity.

[0026] Preferably, R in the terminal group of formula (I) and R in the compound of formula (II) are the same group.

[0027] Preferably, the aldehyde-functional polymer has a polymer backbone containing poly(oxyalkylene) units and / or polyester units.

[0028] In particular, the aldehyde-functional polymer has a poly(oxyalkylene) backbone.

[0029] Preferred poly(oxyalkylene)s are poly(oxy-1,2-propylene), mixed poly(oxy-1,2-propylene)(oxyethylene), poly(oxy-1,3-propylene), poly(oxy-1,4-butylene), poly(oxy-1,2-butylene), or mixed forms of these poly(oxyalkylene)s.

[0030] Among these, poly(oxy-1,2-propylene), poly(oxy-1,3-propylene), or poly(oxy-1,4-butylene), especially poly(oxy-1,2-propylene), is preferred, where the latter may contain poly(oxyethylene) units at a content of 0 wt% to 25 wt%, preferably 0 wt% to 20 wt%, based on the poly(oxyalkylene) backbone, especially at the chain ends. Aldehyde-functional polymers having such a backbone are of low viscosity and can thus function particularly efficiently and are particularly hydrophobic. They enable compositions having particularly good processability, high extensibility, and good water resistance.

[0031] Preferred polymer backbones containing polyester units are esters of dicarboxylic acids with diols or triols, and triglycerides, especially esters derived from dimer fatty acids or castor oil, castor oil, or derivatives of vegetable oils.

[0032] The aldehyde-functional polymer preferably contains less than 1 wt%, preferably less than 0.5 wt%, especially less than 0.2 wt% of formula (II), based on the polymer

Chemical formula

[0033] More preferably, the aldehyde-functional polymer has a poly(oxyalkylene) main chain, and R is

Chemical formula

[0034] Preferably, the aldehyde-functional polymer contains mostly no acid groups. It preferably has an acid group content of less than 0.1% by weight based on the polymer. Such a polymer enables a cured composition that is particularly hydrophobic and has good water resistance.

[0035] The aldehyde-functional polymer is preferably liquid at room temperature. In particular, it has a viscosity low enough to be free-flowing even without any significant heating, and thus can be easily transported, dispensed, and compounded.

[0036] Preferably, the aldehyde-functional polymer has a viscosity at 20 °C of 1 to 500 Pa·s, preferably 2 to 200 Pa·s, particularly 5 to 100 Pa·s, as measured by a cone-plate viscometer with a cone diameter of 10 mm, a cone angle of 1°, a cone tip-plate distance of 0.05 mm, and a shear rate of 10 s -1 -1.

[0037] The aldehyde-functional polymer is preferably a reaction product of at least one hydroxyaldehyde of the formula HO-R-CHO and at least one polymer containing isocyanate groups.

[0038] This reaction is preferably carried out at a temperature of 40 to 140 °C, preferably 60 to 120 °C, with at least a 1 OH / NCO ratio, optionally in the presence of a suitable catalyst and optionally in the presence of a plasticizer.

[0039] The aldehyde-functional polymer preferably does not contain isocyanate groups.

[0040] Suitable hydroxyaldehydes include, inter alia, 2-hydroxyacetaldehyde, 3-hydroxybutanal, 3-hydroxypivalaldehyde, 5-hydroxypentanal, 2-(2-hydroxyethoxy)acetaldehyde, 3-(2-hydroxyethoxy)propanal, 5-hydroxymethylfurfural, alkoxylated o-, m- or p-hydroxybenzaldehyde or alkoxylated vanillin (where "alkoxylated" preferably means (one or more) "ethoxylated" or "propoxylated"), and 4,4'-(2-hydroxypropane-1,3-diyl)bis(oxy)bis(benzaldehyde) or 4,4'-(2-hydroxypropane-1,3-diyl)bis(oxy)bis(3-methoxybenzaldehyde).

[0041] 5-Hydroxymethylfurfural, ethoxylated salicylaldehyde, especially 2-(2-hydroxyethoxy)benzaldehyde, or ethoxylated vanillin, especially 4-(2-hydroxyethoxy)-3-methoxybenzaldehyde, are preferred. These hydroxyaldehydes can be obtained by simple methods and enable low-viscosity aldehyde-functional polymers.

[0042] 5-Hydroxymethylfurfural is particularly preferred. This hydroxyaldehyde can be obtained from renewable starting materials and enables particularly low-viscosity polymers.

[0043] The polymer containing isocyanate groups preferably has a content of monomer diisocyanate of the formula OCN-D-NCO of less than 0.5% by weight, preferably less than 0.2% by weight, especially less than 0.1% by weight, based on the polymer containing isocyanate groups. Such a polymer allows for a particularly low content of the compound of formula (II).

[0044] Suitable polymers containing isocyanate groups for the reaction with hydroxyaldehydes of the formula HO-R-CHO are, inter alia, reaction products of at least one monomer diisocyanate of the formula OCN-D-NCO and at least one polymeric polyol in an NCO / OH ratio in the range of 3 / 1 to 10 / 1, followed by removal of the monomer diisocyanate by a suitable separation method to a content of less than 0.5% by weight, preferably less than 0.2% by weight, especially less than 0.1% by weight, based on the polymer.

[0045] The polymer containing isocyanate groups preferably has an NCO content in the range of 0.6% to 6% by weight, more preferably 0.9% to 3.5% by weight, especially 1.3% to 2.7% by weight, based on the polymer.

[0046] Preferably, the polymer containing isocyanate groups has an average NCO functionality of 1.8 to 4, preferably 2 to 3, especially 2.2 to 3.0.

[0047] Suitable diisocyanates of the formula OCN-D-NCO are, in particular, hexane 1,6-diisocyanate (HDI), 2,2(4),4-trimethylhexane-1,6-diisocyanate (TMDI), 1-methyl-2,4(6)-diisocyanatocyclohexane (H6TDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H 12 MDI), 4(2),4'-diphenylmethane diisocyanate (MDI) or toluene-2,4(6)-diisocyanate (TDI). HDI or IPDI is preferred, and IPDI is particularly preferred.

[0048] Preferred polymer polyols are polymers having an OH number in the range of 9 to 114 mg KOH / g, preferably 12 to 57 mg KOH / g, especially 18 to 45 mg KOH / g, and a polymer backbone containing poly(oxyalkylene) units and / or polyester units.

[0049] Particularly preferred are poly(oxyalkylene) polyols, castor oil, hydroxy-functional derivatives of castor oil, hydroxylated vegetable oils or polyester polyols based on dimer or trimer fatty acids or polyols having poly(oxyalkylene) and polyester units.

[0050] Most preferred are poly(oxyalkylene) polyols.

[0051] Preferred poly(oxyalkylene) polyols, also referred to as polyether polyols, are in particular polymerization products of ethylene oxide or 1,2-propylene oxide or 1,2- or 2,3-butylene oxide or oxetane or tetrahydrofuran or mixtures thereof, where these are polymerized with the aid of starter molecules having two or more active hydrogen atoms, in particular water, ammonia or compounds having two or more OH or NH groups, such as ethane-1,2-diol, propane-1,2- or -1,3-diol, neopentyl glycol, diethylene glycol, triethylene glycol, isomeric dipropylene glycols or tripropylene glycols, isomeric butanediols, pentanediols, hexanediols, heptanediols, octanediols, nonanediols, decanediols, undecanediols, cyclohexane-1,3- or -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 as starter molecules.

[0052] Particularly preferred are those referred to as poly(oxy-1,2-propylene) diol, poly(oxy-1,2-propylene) triol, or ethylene oxide-terminated (EO-endcapped or EO-tipped) poly(oxy-1,2-propylene) diol or triol. The latter are polyoxyethylene-polyoxypropylene copolyols, which are obtained, inter alia, by further alkoxylating polyoxypropylene diol or triol with ethylene oxide at the end of the propoxylation reaction, and as a result they finally have primary hydroxyl groups.

[0053] Also particularly preferred are poly(oxy-1,3-propylene) diol or poly(oxy-1,4-butylene) diol.

[0054] Polyols having an unsaturation level of less than 0.02 meq / g, particularly less than 0.01 meq / g, are preferred.

[0055] The reaction of a monomeric diisocyanate present in a polymer containing isocyanate groups with a hydroxyaldehyde of the formula HO-R-CHO gives a compound of the formula (II). A low monomeric diisocyanate content in the isocyanate group-containing polymer allows for an advantageous low content of the compound of the formula (II) of less than 1% by weight, preferably less than 0.5% by weight, particularly less than 0.2% by weight, based on the polymer.

[0056] The aldehyde-functional polymer of the present invention can be used particularly advantageously for the curing of a compound having at least two reactive groups highly reactive towards aldehydes, which forms a cured composition having elastic properties. The low content of the compound of the formula (II) allows for a particularly long processing time with rapid curing and a particularly high tensile strength and tear propagation resistance with high extensibility.

[0057] The present invention thus further provides the use of an aldehyde-functional polymer for the curing of at least one compound V having at least two reactive groups highly reactive towards aldehydes.

[0058] These reactive groups are preferably selected from cyanoacetate groups, 1,3 - ketoester groups and malonate groups.

[0059] Compound V is preferably liquid at room temperature. In particular, it has a viscosity at 20 °C of 0.1 to 100 Pa·s, preferably 0.2 to 50 Pa·s, especially 0.5 to 20 Pa·s, as measured with a cone - plate viscometer with a cone diameter of 50 mm, a cone angle of 1°, a cone tip - plate distance of 0.05 mm, and a shear rate of 10 s -1 −1 and a viscosity of less than 1 Pa·s. Such compounds enable curable compositions with good processability at ambient temperature and without the addition of a solvent or diluent.

[0060] Compound V preferably has 2 to 4 of the reactive groups described above.

[0061] Compound V preferably has a low water content, especially at most 10% by weight of water based on compound V. Such non - aqueous compounds enable cured compositions with particularly good weather stability.

[0062] Curing is preferably achieved at ambient temperature, especially at a temperature in the range of −5 to 50 °C, preferably 0 to 40 °C.

[0063] More preferably, compound V has at least two cyanoacetate groups. This results in a cured composition having particularly good mechanical properties, especially high extensibility and tear - propagation resistance.

[0064] For the curing of at least one compound V having a cyanoacetate group, the aldehyde - functional polymer is preferably used in an amount such that the ratio of the number of cyanoacetate groups to the number of aldehyde groups is in the range of 0.7 to 1.5, preferably 0.8 to 1.2, especially 0.9 to 1.1.

[0065] Particularly preferred compounds V having a cyanoacetate group are ethan-1,2-diol bis(cyanoacetate), propane-1,2-diol bis(cyanoacetate), propane-1,3-diol bis(cyanoacetate), butane-1,4-diol bis(cyanoacetate), hexane-1,6-diol bis(cyanoacetate), cyclohexane-1,4-dimethanol bis(cyanoacetate), dipropylene glycol bis(cyanoacetate), 1,1,1-trimethylolpropane tris(cyanoacetate), glycerol tris(cyanoacetate), propoxylated 1,1,1-trimethylolpropane tris(cyanoacetate) having an average molecular weight M of 500 to 2000 g / mol, poly(oxy-1,2-propylene) diol bis(cyanoacetate) having an average molecular weight M of 2000 to 10,000 g / mol, poly(oxy-1,2-propylene) triol tris(cyanoacetate) having an average molecular weight M of 2000 to 10,000 g / mol and containing ethylene oxide units, poly(oxy-1,2-propylene) diol bis(cyanoacetate) having an average molecular weight M of 2000 to 10,000 g / mol and containing ethylene oxide units, poly(oxy-1,2-propylene) triol tris(cyanoacetate) having an average molecular weight M of 1000 to 4000 g / mol, dimer fatty acid-based polyester diol bis(cyanoacetate) having an average molecular weight M of 1000 to 4000 g / mol, and trimer fatty acid-based polyester triol tris(cyanoacetate). n Propoxylated 1,1,1-trimethylolpropane tris(cyanoacetate) having an average molecular weight M of 2000 to 10,000 g / mol n Poly(oxy-1,2-propylene) diol bis(cyanoacetate) having an average molecular weight M of 2000 to 10,000 g / mol n Poly(oxy-1,2-propylene) triol tris(cyanoacetate) having an average molecular weight M of 2000 to 10,000 g / mol and containing ethylene oxide units n Poly(oxy-1,2-propylene) diol bis(cyanoacetate) having an average molecular weight M of 2000 to 10,000 g / mol and containing ethylene oxide units n Poly(oxy-1,2-propylene) triol tris(cyanoacetate) having an average molecular weight M of 1000 to 4000 g / mol n Dimer fatty acid-based polyester diol bis(cyanoacetate) having an average molecular weight M of 1000 to 4000 g / mol n Selected from trimer fatty acid-based polyester triol tris(cyanoacetate).

[0066] Such compounds V having a cyanoacetate group, in particular, release and remove the formula R 1 -OH while releasing and removing, formula (III)

Chemical formula

[0067] Preferably, R 1 is here methyl, ethyl or tert-butyl, especially ethyl.

[0068] More preferably, compound V has at least two 1,3-ketoester groups, preferably of formula (IV)

Chemical formula

[0069] In formula (IV), R 2 is a monovalent hydrocarbyl group having 1 to 6 carbon atoms, preferably methyl, ethyl, propyl, isopropyl, butyl or phenyl, especially methyl.

[0070] For the curing of at least one compound V having a 1,3-ketoester group, the aldehyde-functional polymer is preferably used in an amount such that the ratio of the number of 1,3-ketoester groups to the number of aldehyde groups is in the range of 0.5 to 2.5, more preferably 0.8 to 2.2, especially 1 to 2.

[0071] Particularly preferred compounds V having a 1,3-ketoester group are ethylene glycol bis(acetoacetate), propylene-1,2-diol bis(acetoacetate), propane-1,3-diol bis(acetoacetate), butane-1,4-diol bis(acetoacetate), hexane-1,6-diol bis(acetoacetate), cyclohexane-1,4-dimethanol bis(acetoacetate), dipropylene glycol bis(acetoacetate), 1,1,1-trimethylolpropane tris(acetoacetate), glycerol tris(acetoacetate), propoxylated 1,1,1-trimethylolpropane tris(acetoacetate) having an average molecular weight M of 500 to 2000 g / mol, poly(oxy-1,2-propylene) diol bis(acetoacetate) having an average molecular weight M of 600 to 10,000 g / mol, poly(oxy-1,2-propylene) triol tris(acetoacetate) having an average molecular weight M of 2000 to 10,000 g / mol, poly(oxy-1,2-propylene) triol tris(acetoacetate) containing ethylene oxide units and having an average molecular weight M of 2000 to 10,000 g / mol, poly(oxy-1,2-propylene) triol tris(acetoacetate) having an average molecular weight M of 2000 to 10,000 g / mol, polyester diol bis(acetoacetate) based on dimer fatty acids, and polyester triol tris(acetoacetate) based on trimer fatty acids, selected from n Propoxylated 1,1,1-trimethylolpropane tris(acetoacetate) having an average molecular weight M of 600 to 10,000 g / mol n Poly(oxy-1,2-propylene) diol bis(acetoacetate) having an average molecular weight M of 2000 to 10,000 g / mol n Poly(oxy-1,2-propylene) triol tris(acetoacetate) having an average molecular weight M of 2000 to 10,000 g / mol, containing ethylene oxide units and having an average molecular weight M of 2000 to 10,000 g / mol n Poly(oxy-1,2-propylene) triol tris(acetoacetate) having an average molecular weight M of 2000 to 10,000 g / mol, containing ethylene oxide units and having an average molecular weight M of 2000 to 10,000 g / mol, polyester diol bis(acetoacetate) based on dimer fatty acids, and polyester triol tris(acetoacetate) based on trimer fatty acids, selected from

[0072] Such compounds V having a 1,3-ketoester group are obtained, inter alia, by transesterification of at least one 1,3-ketoester of the formula R 4 OH with at least one polyfunctional alcohol, while releasing and removing the alcohol of the formula (V)

Chemical formula

[0073] Preferably, R 3 is methyl, ethyl, propyl, isopropyl, butyl or phenyl, preferably methyl or phenyl, especially methyl, and R 4 is methyl, ethyl or tert-butyl, especially ethyl.

[0074] The compound V having a 1,3-ketoester group can also be obtained by reacting diketene or an adduct of diketene and acetone (=2,2,6-trimethyl-4H-1,3-dioxin-4-one) with at least one polyfunctional alcohol while releasing acetone in the case of an acetone-diketene adduct.

[0075] More preferably, the compound V has at least two malonate groups, especially a malonate group of the formula

Chemical formula

[0076]

[0077] ​Particularly preferred compounds V having a malonate group are ethylene-1,2-diol bis(ethyl malonate), propane-1,2-diol bis(ethyl malonate), propane-1,3-diol bis(ethyl malonate), butane-1,4-diol bis(ethyl malonate), hexane-1,6-diol bis(ethyl malonate), cyclohexane-1,4-dimethanol bis(ethyl malonate), diethylene glycol bis(ethyl malonate), dipropylene glycol bis(ethyl malonate), glycerol tris(ethyl malonate), 1,1,1-trimethylolpropane tris(ethyl malonate), dimer fatty acid diol bis(ethyl malonate), trimer fatty acid triol tris(ethyl malonate), castor oil tris(ethyl malonate), poly(oxy-1,2-propylene) diol bis(ethyl malonate) having an average molecular weight M of 500 to 2000 g / mol, propoxylated 1,1,1-trimethylolpropane having three ethyl malonate end groups and an average molecular weight M of 650 to 2500 g / mol, the corresponding oligomeric compounds of these reaction products, and a polyester diol containing a malonate group selected from the reaction of a diol such as hexane-1,6-diol or cyclohexane-1,4-dimethanol with malonic acid or diethyl malonate and optionally a further dicarboxylic acid or their esters, for example, particularly adipic acid or diethyl adipate or dimer fatty acid. n and poly(oxy-1,2-propylene) diol bis(ethyl malonate) having an average molecular weight M of 500 to 2000 g / mol, three ethyl malonate end groups and an average molecular weight M of 650 to 2500 g / mol n selected from the reaction of propoxylated 1,1,1-trimethylolpropane having these, the corresponding oligomeric compounds of these reaction products, and a diol such as hexane-1,6-diol or cyclohexane-1,4-dimethanol with malonic acid or diethyl malonate and optionally a further dicarboxylic acid or their esters, for example, particularly adipic acid or diethyl adipate or dimer fatty acid.

[0078] Suitable compounds V having a malonate group are, inter alia, obtained from the reaction of at least one polyfunctional alcohol with malonic acid or a malonate of formula (VI)

Chemical formula

[0079] Preferably, R 5 and R6 is methyl, ethyl or isopropyl, especially ethyl.

[0080] Preferred malonates of formula (VI) are dimethyl malonate, diethyl malonate, diisopropyl malonate, butyl ethyl malonate, tert-butyl ethyl malonate or di-tert-butyl malonate. Dimethyl malonate, diethyl malonate or diisopropyl malonate, especially diethyl malonate, is preferred.

[0081] Suitable polyfunctional alcohols for the reaction with the cyanoacetate of formula (III) or the 1,3-ketoester of formula (V) or the malonate of formula (VI) are, in particular, ethane-1,2-diol, propylene glycol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, cyclohexane-1,3-dimethanol, cyclohexane-1,4-dimethanol, diethylene glycol, dipropylene glycol, 1,1,1-trimethylolpropane, glycerol, ethoxylated or especially propoxylated glycerol, ethoxylated or especially propoxylated 1,1,1-trimethylolpropane, castor oil, ethoxylated or especially propoxylated castor oil, ketone resin-modified castor oil, poly(oxy-1,2-propylene) diol or triol, poly(oxy-1,2-propylene) diol or triol end-capped with ethylene oxide, dimer fatty acid diol or trimer fatty acid triol or polyester diol or triol based on dimer or trimer fatty acid, etc., which are commercially available compounds or polymers having two or more OH groups.

[0082] Compound V having a malonate group can also be obtained from the reaction of malonic acid with a polyfunctional alcohol having an excess of OH groups. Here, the stoichiometry in this reaction (the molar equivalent of the OH groups of the polyfunctional alcohol per mole of malonic acid) is preferably in the range of 2.2 to 3.5, preferably 2.3 to 3.3. In this reaction, it is also possible, in particular, to use further dicarboxylic acids, such as adipic acid.

[0083] Compound V having mixed reactive groups, i.e., for example, having at least one cyanoacetate group and at least one acetoacetate, or having at least one cyanoacetate group and at least one malonate group, or having at least one acetoacetate and at least one malonate, is likewise possible.

[0084] It is preferred to use an aldehyde-functional polymer for the curing of at least one compound V as a constituent of a two-component composition, where the first component contains the aldehyde-functional polymer of the present invention and the second component contains compound V, and where the first and second components are storage-stable per se and are stored in separate containers until they are mixed with each other immediately before or during application.

[0085] The two-component composition may further contain additional constituents, in particular fillers, fibers, nanofillers such as graphene or carbon nanotubes, dyes, pigments, plasticizers, solvents, rheology modifiers, in particular adhesion promoters such as titanates or organoalkoxysilanes, catalysts, in particular non-metallic bases such as tertiary amines, amidines or guanidines, or, in particular, basic salts such as potassium acetate, potassium benzoate, potassium carbonate or sodium acetate, especially as an aqueous solution, or flame-retardant substances, in particular additives such as wetting agents, leveling agents, defoamers, degassing agents or stabilizers against oxidation, heat, light or UV radiation, or other substances customarily used in curable compositions.

[0086] Such an addition may be present as a constituent of the first component or the second component. A substance highly reactive with an aldehyde group is preferably a constituent of the second component.

[0087] The composition preferably further contains at least one additional constituent selected from plasticizers, fillers, and catalysts. In particular, it contains several such additional constituents.

[0088] The composition preferably contains a volatile organic solvent having a boiling point of less than 250°C at standard pressure of less than 10% by weight, more preferably less than 5% by weight, especially less than 1% by weight, based on the total composition. Such a composition causes particularly low levels of emissions.

[0089] The consistency of the first and second components is preferably such that the components can be efficiently mixed with each other by a simple method under ambient conditions. For this purpose, liquid or paste-like components are particularly suitable.

[0090] For application, the two components and any additional components present are mixed with each other immediately before or during application. The mixing ratio is here selected such that the ratio of the reactive groups is within a suitable range. In parts by weight, the mixing ratio between the first component and the second component is typically in the range of about 100:1 to 1:5, especially 50:1 to 1:2.

[0091] If the components are mixed with each other before application, it must be ensured that not too much time elapses between the mixing and the application of the components, since the start of the reaction and the associated increase in viscosity would otherwise lead to problems, such as insufficient spreading or delayed or incomplete adhesion to the substrate.

[0092] The "processing time" here refers to the period between the mixing of the components and the end of the state of the composition suitable for processing. A long processing time is particularly advantageous in the case of subsequent rapid curing.

[0093] Mixing and curing are preferably achieved at ambient temperature.

[0094] Mixing of the two components initiates curing of the composition by starting a chemical reaction. It is mainly the reactive groups present in compound V that react here with aldehyde groups which ultimately cure the composition to give a solid polymeric material.

[0095] In the case of the cyanoacetate group as a reactive group of compound V, the curing reaction is expected to form structural units of the formula

Chemical formula

[0096] In the case of the 1,3 - ketoester group as a reactive group of compound V, the curing reaction is expected to form structural units of the formula

Chemical formula

[0097] In the case of the malonate group as a reactive group of compound V, the curing reaction is expected to form structural units of the formula

Chemical formula

[0098] In particular, the curing results in an elastic material having a tensile strength of at least 1 MPa, preferably at least 2 MPa, measured according to DIN EN 53504 at a strain rate of 200 mm / min, and a breaking elongation of at least 50%, preferably at least 100%, and at least 200%, especially at least 400% of the mechanical properties.

[0099] The aldehyde-functional polymers of the present invention having the end groups of formula (I) enable particularly long processing times with rapid curing and particularly high tensile strength and tear propagation resistance with high extensibility, which means that such polymer systems have particularly good processability and are particularly robust and long-lived.

[0100] The aldehyde-functional polymers of the present invention contain little or no toxic raw materials, are not very sensitive to moisture, and are particularly suitable as components of elastic adhesives, sealants or coatings having high stability and robustness after curing.

Examples

[0101] Examples are presented below in this specification with the intention of further clarifying the present invention as described. It will be clear that the present invention is not limited to these described examples.

[0102] “Standard climatic conditions” (“SCC”) refers to a temperature of 23 ± 1 °C and a relative atmospheric humidity of 50 ± 5%.

[0103] The chemicals used were from Sigma-Aldrich Chemie GmbH unless otherwise specified.

[0104] Description of measurement methods: The monomeric isocyanate content was measured by HPLC (detection by photodiode array; 0.04 M sodium acetate / acetonitrile as mobile phase) after prior derivatization with N-propyl-4-nitrobenzylamine.

[0105] Viscosity was measured with a Rheotec RC30 cone-plate viscometer at constant temperature (cone diameter 10 mm, cone angle 1°, cone tip-plate distance 0.05 mm, shear rate 10 s -1 ). Viscosities below 1 Pa·s were measured with a 50 mm cone diameter.

[0106] The infrared spectrum (FT-IR) was measured as undiluted film using a Nicolet iS5 FT-IR instrument from Thermo Scientific equipped with a horizontal ATR measurement unit for diamond crystal. The absorption bands are reported in wave number (cm -1 ) units.

[0107] Preparation of polymers containing isocyanate groups: Polymer NCO-1: 780 g of ethylene oxide-terminated polyoxypropylene triol (Desmophen® 5031 BT, OH value 28.0 mg KOH / g, manufactured by Covestro) and 303 g of isophorone diisocyanate (Vestanat® IPDI, manufactured by Evonik) were converted at 80 °C by a known method into a reaction mixture having an NCO content of 9.1% by weight. Subsequently, volatile constituents, in particular unconverted isophorone diisocyanate, were removed by distillation using a short-path evaporator (jacket temperature 160 °C, pressure 0.1 - 0.005 mbar) to obtain a polymer having an NCO content of 1.84% by weight and a monomer isophorone diisocyanate content of 0.02% by weight.

[0108] Polymer NCO-2 894.5 g of ethylene oxide-terminated polyoxypropylene triol (Desmophen® 5031 BT, OH value 28.0 mg KOH / g, manufactured by Covestro) and 102.0 g of isophorone diisocyanate (Vestanat® IPDI, manufactured by Evonik) were converted at 80 °C by a known method in the presence of 0.01 g of dibutyltin dilaurate into a polymer having an NCO content of 1.83% by weight and a monomer isophorone diisocyanate content of 1.4% by weight.

[0109] Polymer NCO-3: 590 g of polyoxypropylene diol (Acclaim® 4200, OH value 28 mg KOH / g, manufactured by Covestro), 1180 g of ethylene oxide-terminated polyoxypropylene triol (Caradol® MD34-02, OH value 35 mg KOH / g, manufactured by Shell), and 230 g of isophorone diisocyanate (Vestanat® IPDI, manufactured by Evonik) were converted at 80 °C by a known method into a polymer having an NCO content of 2.1 wt% and a monomer isophorone diisocyanate content of 1.3 wt%.

[0110] Polymer NCO-4: 818 g of polyoxypropylene diol (Acclaim® 4200, OH value 28.5 mg KOH / g, manufactured by Covestro) and 227 g of isophorone diisocyanate (Vestanat® IPDI, manufactured by Evonik) were converted at 80 °C by a known method into a reaction mixture having an NCO content of 6.6 wt%. Subsequently, volatile constituents, in particular unconverted isophorone diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 160 °C, pressure 0.1 to 0.005 mbar) to obtain a polymer having an NCO content of 1.91 wt% and a monomer isophorone diisocyanate content of 0.03 wt%.

[0111] Polymer NCO-5: 600 g of polyoxypropylene diol (Voranol® 1010 L, OH value 112 mg KOH / g, manufactured by Dow) and 533.3 g of isophorone diisocyanate (Vestanat® IPDI, manufactured by Evonik) were converted at 80 °C by a known method into a reaction mixture having an NCO content of 15.6 wt%. Subsequently, volatile constituents, in particular unconverted isophorone diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 160 °C, pressure 0.1 to 0.005 mbar) to obtain a polymer having an NCO content of 5.18 wt% and a monomer isophorone diisocyanate content of 0.03 wt%.

[0112] Polymer NCO-6: 150 g of polyoxypropylene diol (Voranol® P400, OH value 263 mg KOH / g, manufactured by Dow) and 156.4 g of isophorone diisocyanate (Vestanat® IPDI, manufactured by Evonik) were converted at 80 °C by a known method into a reaction mixture having an NCO content of 9.65% by weight and a monomer isophorone diisocyanate content of more than 1% by weight.

[0113] Preparation of aldehyde-functional polymer: Polymers A-1 to A-8: For each of the compounds, the corresponding polymer containing the isocyanate groups in the amounts (in parts by weight) specified in Table 1 was reacted with the corresponding hydroxy-functional aldehyde in the amounts (in parts by weight) specified until the isocyanate groups were no longer detectable by IR spectroscopy, with the exclusion of moisture at 110 °C and in the presence of 0.02% by weight of dibutyltin dilaurate.

[0114] [Table 1]

[0115] The average molecular weight M of Polymer A-1 n was further measured by gel permeation chromatography (GPC) against polystyrene (474 - 2,520,000 g / mol) as a standard using tetrahydrofuran as the mobile phase and a refractive index detector. The average molecular weight M n was 6100 g / mol.

[0116] Polymer A-8, denoted as "(Ref)", is a comparative example having an average aldehyde group content of 1.07 meq / g, i.e., outside the claimed scope. It is a glassy solid at room temperature and was therefore not used for the production of the curable composition.

[0117] Production of a compound having at least two reactive groups: Compound V-1: (having a cyanoacetate group) To 50.0 g of trimethylolpropane-initiated poly(oxy-1,2-propylene) triol (Desmophen® 4011 T, OH value 550 mg KOH / g, manufactured by Covestro), 61.0 g of ethyl cyanoacetate and 0.1 g of tetra-n-butyl titanate (Tyzor® TnBT, manufactured by Dorf Ketal) were added, and the mixture was converted at a temperature of 140 °C while distilling off ethanol under reduced pressure. The resulting product was a transparent, colorless liquid having a viscosity of 1.72 Pa·s at 20 °C, a cyanoacetate functionality of 3, and a calculated cyanoacetate equivalent of 169 g / equivalent.

[0118] Compound V-2: (having an acetoacetate group) To 50.0 g of trimethylolpropane-initiated poly(oxy-1,2-propylene) triol (Desmophen® 4011 T, OH value 550 mg KOH / g, manufactured by Covestro), 67.0 g of ethyl acetoacetate and 0.1 g of tetra-n-butyl titanate (Tyzor® TnBT, manufactured by Dorf Ketal) were added, and the mixture was converted at a temperature of 140 °C while distilling off ethanol under reduced pressure. The resulting product was a transparent, colorless liquid having a viscosity of 0.8 Pa·s at 20 °C, an acetoacetate functionality of 3, and a calculated acetoacetate equivalent of 186 g / equivalent.

[0119] Compound V-3: (having a malonate group) To 123.4 g of trimethylolpropane-initiated poly(oxy-1,2-propylene) triol (Desmophen® 4011 T, OH value 550 mg KOH / g, manufactured by Covestro), 192.2 g of diethyl malonate and 0.3 g of tetra-n-butyl titanate (Tyzor® TnBT, manufactured by Dorf Ketal) were added, and the mixture was converted at a temperature of 140 °C while under reduced pressure and removing ethanol by distillation. The resulting product was a transparent, colorless liquid having a viscosity at 20 °C of 7.3 Pa·s, a malonate functionality of about 3, and an estimated malonate equivalent weight of 217 g / equivalent.

[0120] Production of curable composition Compositions Z-1 to Z-10 For each example, the raw materials of the first component (K1) specified in Tables 2 and 3 were mixed in the specified amounts (in parts by weight) using a centrifugal mixer (SpeedMixer™ DAC 150, FlackTek Inc.) and stored in a sealed container.

[0121] The raw materials of the second component (K2) specified in Tables 2 and 3 were similarly treated and stored.

[0122] The "precipitated CaCO3" used was Socal® U1S2 (manufactured by Imerys), a precipitated and stearate-coated calcium carbonate.

[0123] The "carbon black" used was Monarch® 570 (manufactured by Cabot).

[0124] The two components of each composition were then treated using a centrifugal mixer to give a homogeneous liquid, and the liquid was immediately tested as follows.

[0125] The gelation time was measured by stirring about 3 g of the freshly mixed amount at regular intervals using a spatula under standard climatic conditions until stirring was no longer possible as a result of the gelation of the mass.

[0126] The mechanical properties were measured by applying the mixed composition to silicone-coated release paper to obtain a film with a thickness of 2 mm, curing the film under standard climatic conditions for 7 days, cutting out test specimens in the shape of 2 or 3 dumbbells with a test specimen length of 30 mm and a test specimen width of 4 mm and having a length of 75 mm from the film, and testing them according to DIN EN 53504 at a strain rate of 200 mm / min with respect to the tensile strength, elongation at break, and modulus of elasticity MoE5% (at 0.5% to 5% elongation) and MoE50% (at 0.5% to 50% elongation). Furthermore, a number of test specimens were cut out for the measurement of tear propagation resistance and tested according to DIN ISO 34-1, method B (angle test specimen) at a strain rate of 500 mm / min.

[0127] The Shore A hardness was measured according to DIN 53505 for test specimens cured under standard climatic conditions for 7 days. These results are shown in the additional "7d SCC". For some compositions, the Shore A hardness was also measured and specified after curing for 1 day, 2 days, and 4 days. The heat resistance and water resistance were determined for some compositions by further storing the Shore A test specimens, after curing them under standard climatic conditions for 7 days, in an air-circulation oven at 100 °C for a further 7 days or at either 70 °C and 100% relative humidity for a further 7 days, cooling them to room temperature, and then measuring the Shore A hardness as described in each case. These results are shown in the additional "+7d 100 °C" or "+7d 70 / 100".

[0128] Curing in each case resulted in a non-sticky, elastic material.

[0129] The results are reported in Tables 2 and 3.

[0130]

Table 2

[0131] From Table 2, it is clear that composition Z-1 containing only polymer A-1 having 0.04% by weight of the compound of formula (II) has a longer processing time with rapid curing, a higher tensile strength with high extensibility, and tear propagation resistance compared to compositions Z-2 and Z-3 containing polymers A-2 and A-3, which have high contents of the compound of formula (II) at 2.8% and 2.6% by weight, respectively.

[0132]

Table 3

Claims

1. A nonionic aldehyde-functional polymer having a terminal group of formula (I), 【Chemistry 1】 Having an average aldehyde group content of 0.15 to 1.2 milliequivalents / g, preferably 0.2 to 0.75 milliequivalents / g, more preferably 0.2 to 0.7 milliequivalents / g, and particularly 0.3 to 0.6 milliequivalents / g, During the ceremony, R is a divalent organic group having 1 to 15 carbon atoms. D is a nonionic aldehyde-functional polymer, where D is a divalent hydrocarbyl group having 4 to 15 carbon atoms.

2. Average molecular weight M ｎ The aldehyde-functional polymer according to claim 1, characterized in that, when measured by gel permeation chromatography (GPC) against polystyrene as a standard, it is in the range of 1,500 to 20,000 g / mol, preferably 2,500 to 15,000 g / mol, and particularly 3,500 to 8,000 g / mol.

3. The aldehyde-functional polymer according to any one of claims 1 and 2, characterized in that the average aldehyde functional value is 1.8 to 4, preferably 2.0 to 3, and particularly 2.2 to 3.

0.

4. The aldehyde-functional polymer according to any one of claims 1 and 2, characterized in that R is a linear or branched alkylene group, cycloalkylene group, arylalkylene group, or aryl group, which may also contain oxygen and / or nitrogen atoms.

5. The aldehyde-functional polymer according to any one of claims 1 and 2, characterized in that D is a divalent group of hexane-1,6-diamine, 2,2(4),4-trimethylhexane-1,6-diamine, 1-methyl-2,4(6)-diaminocyclohexane, isophorone diamine, 4,4'-diaminodicyclohexylmethane, diphenylmethane-4(2),4'-diamine, or toluene-2,4(6)-diamine after the removal of two amino groups, preferably a group of hexane-1,6-diamine or isophorone diamine after the removal of two amino groups.

6. An aldehyde-functional polymer according to any one of claims 1 and 2, characterized by having a polymer main chain containing poly(oxyalkylene) units and / or polyester units.

7. The aldehyde-functional polymer according to any one of claims 1 and 2, characterized in that it contains less than 1% by weight of the compound of formula (II) based on the polymer. 【Chemistry 2】

8. The aldehyde-functional polymer according to any one of claims 1 and 2, characterized in that it has an acid group content of less than 0.1% by weight, based on the polymer.

9. Cone diameter 10 mm, cone angle 1°, cone tip-to-plate distance 0.05 mm, shear rate 10 s －１ The aldehyde-functional polymer according to any one of claims 1 and 2, characterized in that it has a viscosity at 20°C of 1 to 500 Pa·s, preferably 2 to 200 Pa·s, and particularly 5 to 100 Pa·s, as measured by a cone-plate viscometer.

10. The aldehyde-functional polymer according to any one of claims 1 and 2, characterized in that it is a reaction product of at least one hydroxyaldehyde of the formula HO-R-CHO with at least one polymer containing an isocyanate group.

11. The aldehyde-functional polymer according to claim 10, characterized in that the polymer containing isocyanate groups is a reaction product of at least one monomer diisocyanate of formula OCN-D-NCO with at least one polymer polyol in an NCO / OH ratio in the range of 3 / 1 to 10 / 1, and by subsequent treatment, the monomer diisocyanate is removed by a suitable separation method to an amount of less than 0.5% by weight relative to the polymer containing isocyanate groups.

12. The aldehyde-functional polymer according to claim 11, characterized in that the polymer polyol is a polymer having a polymer main chain containing poly(oxyalkylene) units and / or polyester units, with an OH value in the range of 9 to 114 mg KOH / g, preferably 12 to 57 mg KOH, and particularly 18 to 45 mg KOH / g.

13. Use of an aldehyde-functional polymer according to any one of claims 1 and 2 for curing at least one compound V having at least two reactive groups that are highly reactive with aldehydes.

14. The use according to claim 13, characterized in that the curing is achieved at ambient temperature, particularly in the range of -5 to 50°C, preferably 0 to 40°C.

15. The use according to claim 13, characterized in that the hardening yields an elastic material having a tensile strength of at least 1 MPa, preferably at least 2 MPa, and particularly at least 3 MPa, and an elongation at break of at least 50%, preferably at least 100%, more preferably at least 200%, and particularly at least 400%, as measured according to DIN EN 53504 at a strain rate of 200 mm / min.

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