Compositions polyaspartiques

Abstract

The invention relates to coating preparation compositions comprising at least one polyaspartic ester compound, at least one isocyanate compound and optionally at least one additive.

Description

Title of the invention: Polyaspartic compositions Technical field

[0001] The invention relates to a coating preparation composition comprising a polyaspartic ester and an isocyanate compound.

[0002] The invention also relates to a process for preparing such compositions as well as the use of such compositions as a protective coating.

[0003] The invention also relates to a protective coating comprising the polyaspartic compositions.

[0004] In particular, the invention relates to a composition for the preparation of a coating whose flexibility is improved, as well as the pot life of a formulation for paint or varnish and whose viscosity is reduced. State of the art

[0005] Coatings comprising polyaspartic esters are mainly used for their rapid crosslinking properties, resistance to abrasion, corrosion and / or their use in formulations with a high dry extract content.

[0006] As an example of these compositions comprising polyaspartic esters, mention may be made of patent EP0573860 which describes a composition comprising a polyisocyanate, a polyaspartic ester and a catalyst. Patent application WO202016292 describes another type of composition comprising at least one polyaspartic ester, at least one isocyanate prepolymer and a catalyst.

[0007] Generally, compositions comprising polyaspartic esters have very short pot lives and are very inflexible (elongation at break < 50%). In addition, some of these polyaspartic compositions comprise solvents or catalysts, which can lead to other problems.

[0008] Pot life times are generally improved by:

[0009] the use of solvent in compositions comprising polyaspartic esters which makes it possible to reduce the viscosity of the composition and its crosslinking speed,

[0010] the use of low viscosity reactive diluents generally in small quantities (< 30 wt%).

[0011] The use of solvents or reactive diluents in small quantities makes it possible to solve the problems of too short pot life, but does not make it possible to improve the flexibility of a composition comprising polyaspartic esters.

[0012] To solve this particular problem of flexibility, elastomeric isocyanate prepolymer compounds are often added to polyaspartic compositions. These isocyanate prepolymers generally have a low NCO titer (< 13%) and a high viscosity (> 1500 mPa.s), which limits their application possibilities.

[0013] Therefore, these polyaspartic compositions generally include significant amounts of solvent in order to lower or control their viscosity and / or improve pot life. These solvents are usually volatile organic compounds (VOCs) or sources of such VOCs.

[0014] Furthermore, the addition of catalysts proves problematic in view of the toxicity they induce, whether for the health of the handlers or for the environment.

[0015] There is therefore a need to find new polyaspartic compositions based on isocyanate without solvent or catalysts, flexible (elongation at break > 50%) and whose viscosity of the isocyanate part is low (< 1500 mPa.s).

[0016] Thus, the present invention provides a composition for preparing a coating which is particularly advantageous in the field of ground covering or wind power.

[0017] The invention makes it possible to provide a solution to the various problems linked to the coating preparation compositions of the state of the art, in particular the problems linked to the difficulty of application when the composition is too viscous, but also the problems linked to the ductility of the coatings when they are not flexible enough. Statement of the invention

[0018] The invention relates to coating preparation compositions having improved elongation and the isocyanate part of which has an NCO titre greater than 13% and an acceptable viscosity, i.e. less than 1500 mPa.s at 25°C. By improved elongation property is meant an elongation at break greater than 50%.

[0019] In particular, the invention relates to a coating preparation composition comprising:

[0020] at least one polyaspartic ester compound (a), at least one isocyanate compound (b),

[0021] optionally at least one additive (c).

[0022] The invention relates more specifically to a composition for the preparation of a coating in which the isocyanate compound (b) is a mixture of isocyanates comprising: at least one allophanate (bl) and at least one polyfunctional isocyanate (b2) and in which the mass ratio (b 1 ) / (b2) is between 50 / 50 and 99 / 1.

[0023] Preferably, the mass ratio (b 1 ) / (b2) is between 55 / 45 and 95 / 5. Even more preferably, the mass ratio (b 1 ) / (b2) is between 60 / 40 and 95 / 5.

[0024] The molar ratio between the mixtures (a) and (b) defined by the number of NH functions for (a) and the number of NCO functions for (b) is between 0.7 and 1.3, preferably 0.8 to 1.2, more preferably 0.9 to 1.1 or even more preferably is equal to 1. The number of NCO functions of the compound (b) is equal to the sum of the number of NCO functions of the compound (b1) and of the compound (b2).

[0025] The polyaspartic ester (a) preferably has an NH group content of between 2 and 8% by mass, more preferably between 3 and 7%.

[0026] The polyaspartic ester (a) preferably has a viscosity ranging from 500 to 4000 mPa.s.

[0027] The polyaspartic ester (a) according to the invention is obtained by the Michael reaction of a system comprising a polyamine and an ester. This ester is preferably a maleate or a fumarate or a mixture thereof.

[0028] According to the invention, the term "polyamine" refers to compounds comprising at least two free primary and / or secondary amine groups. The term "polyamine" also includes polymers comprising at least two pendant and / or terminal amine groups.

[0029] The reaction to prepare the polyaspartic ester (a) can be carried out without solvent or in the presence of a suitable solvent. This solvent is preferably one or more alcohols, ethers, acetates, ketones or a mixture thereof.

[0030] The alcohol(s) used as solvents may be, for example, methanol, ethanol, butyl glycol and propanol. The acetate used as solvent is preferably n-butyl acetate.

[0031] The ketone used as solvent is preferably methyl ethyl ketone dialkane.

[0032] The polyaspartic ester (a) is preferably a polyaspartic ester according to the general formula (I):

[0033] [Chem 1]

[0034] in which X represents an aliphatic chain or a polyether chain, R1 and R2 are, independently of each other, an organic group which is inert towards an isocyanate group at normal atmospheric pressure (about 100 Pa) and at 100°C or less, n represents an integer greater than or equal to 2.

[0035] Preferably, R1 and R2 are, independently of each other, an alkyl residue having 1 to 10 carbon atoms, more preferably R1 and R2 are, independently of each other, chosen from methyl, ethyl or butyl groups.

[0036] n is preferably an integer between 2 and 4, more preferably 2.

[0037] Preferably, in general formula (I), X is composed of one or more of the following residues: a polyether residue, a linear alkyl residue, a branched alkyl residue and a cycloalkyl residue.

[0038] In the general formula (I), if n = 2, the polyaspartic ester (a) is prepared by reaction of a polyamine of formula (La) and a maleate and / or a fumarate of formula (Ib).

[0039] [Chem 1 a, b]

[0040] The polyamine of formula (La) is preferably chosen from ethylenediamine, 1,2-diaminopropane, 1,4-diaminobutane, 1,3-diaminopentane, 1,6-diaminohexane, 2,5-diamino-2,5-dimethylhexane, 1,6-diaminohexane, 2,2,4-trimethyl-1,6-diaminohexane, 2,4,4-trimethyl-1,6-diaminohexane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,3-cyclohexanediamine and 1,4-cyclohexanediamine, amino-3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4-hexahydrotoluenediamine, 2,6-hexahydrotoluenediamine, 2,4'-diamino-dicyclohexylmethane, 4,4'-diamino-dicyclohexylmethane, 3,3'-dialkyl-4,4'-diaminodicyclohexylmethane, 2,4,4'-triamino-5-methyldicyclohexylmethane, 2-methyl-1,5-pentanediamine, 1,3-xylcncdiaminc and 1,4-xylenediamine; and more preferably selected from 1,4-aminobutane, 1,6-diaminohexane, 2,2,4-trimethyl-1,6-diaminohexane, 2,4,4-trimethyl-1,6-diaminohexane, amino- 3,3,5-trimethyl-5-aminomethylcyclohexane, 4,4'-diamino-dicyclohexylmethane, 3,3'-dialkyl-4,4'-diaminodicyclohexylmethane, 2-methyl-1,5-pentanediamine; even more preferably selected from 2-methyl-1,5-pentanediamine, amino- 3,3,5-trimethyl-5-aminomethylcyclohexane, 2,4'-diamino-dicyclohexylmethane, 4,4'-diamino-dicyclohexylmethane and 3,3'-dialkyl-4,4'-diaminodicyclohexylmethane, polyetherpolyamine of functionality 2 and number average molar mass (Mn) less than 1000 g / mol.

[0041] The maleate and / or fumarate of formula (Ib) are preferably chosen from dimethyl maleate, diethyl maleate, dibutyl maleate, dimethyl fumarate, diethyl fumarate and dibutyl fumarate.

[0042] The molar ratio between maleate and / or fumarate (Ib) and polyamine (La) is preferably 2:1.

[0043] The molar ratio between the olefinic double bonds of the maleate and / or fumarate (Ib) and the primary amino groups of the polyamine (La) is preferably 1:1.

[0044] The product obtained from the reaction between (La) and (Ib) is preferably purified by distillation in order to obtain the polyaspartic ester (a).

[0045] Reaction components (Ia) and (Ib) may or may not comprise a solvent, and preferably comprise a solvent.

[0046] The solvent is preferably one or more of the following solvents: methanol, ethanol, propanol and / or dioxane.

[0047] The polyaspartic ester(s) (a) of general formula (I) are one or more polyaspartic esters or a mixture of polyaspartic esters:

[0048] of general formula (II) and / or,

[0049] [Chem 2]

[0050] of general formula (III) and / or

[0051] [Chem 3]

[0052] of general formula (IV) and / or

[0053] [Chem 4]

[0054] of general formula (V) and / or

[0055] [Chem 5]

[0056] in which the groups R 1 and R 2 are, independently of each other, a C 1 -C 10 alkyl group and u is an integer between 1 and 10.

[0057] Preferably, u is an integer between 2 and 6, even more preferably, u is an integer between 2 and 4.

[0058] Preferably, in the general formulas (II), (III), (IV) and (V), the groups R 1 and R 2 are, independently of one another, one or more methyls, ethyls or butyls, preferably R 1 and R 2 are ethyl groups.

[0059] The polyaspartic ester (a) is more preferably chosen from the compounds reactive with isocyanates described in patents US512617, US523674, US5489704, US5243012, US5736604, US6458293, US6833424, US7169876 or US2006 / 0247371.

[0060] The polyaspartic ester (a) is even more preferably chosen from N,N'-(methylenedicyclohexane-4,l-diyl)bis-DL-tetraethyl aspartate, N,N'-(m-ethylenebis(2-methyl-cyclohexane-4,l-diyl)bis-DL-tetraethyl aspartate or N,N'-(2-methylpentane)bis-DL-tetraethyl aspartate

[0061] According to the invention, the allophanate (bl) has an NCO functionality equal to 2.1 + 0.3 or preferably 2.1 ± 0.2 or preferably 2.1 ± 0.1 and has the general formula (VI)

[0062] [Chem 6]

[0063] in which R3 and R4, which may be identical or different, represent a hydrocarbon group, chosen from an isocyanate, carbamate, urea, biuret ure-tinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function,

[0064] R5 represents the remainder of a molecule comprising an OH function after reaction of this OH with an isocyanate function and the molecule of which with the OH group may also comprise an ether or polyether function and chosen from a silanol, a linear chain C12-C20 aliphatic monoalcohol, a branched chain C12-C20 aliphatic monoalcohol, a linear chain C2-C40 diol or a branched chain C3-C40 diol of which at least one of the hydroxyl groups is substituted and which is of general formula (VII):

[0065] [Chem 7]

[0066] in which Ti represents a linear C1-C20 alkyl group, a branched C1-C20 alkyl group, a group of formula T3-CO-CH3 in which T3 represents a linear C1-C20 alkyl group or a branched C1-C20 alkyl group; T2 represents a hydrogen or an alkyl group, preferably a C1-C8 alkyl group or an ether group of formula -CH2OT4 in which T4 represents a chain hydrocarbon, in particular a polyalkylene chain or a polyoxyalkylene chain or a polyoxyethylene chain; m represents an integer ranging from 1 to 50.

[0067] By blocked isocyanate function is meant any isocyanate function having reacted with an isocyanate function blocking agent. The different blocking reactions are reversible and the unblocking conditions are known to those skilled in the art.

[0068] Preferably, T4 represents a polyalkylene chain or a polyoxyalkylene chain or a polyoxyethylene chain.

[0069] Preferably, the allophanate (bl) is a compound of general formula (VI) in which R3 and R4, which may be identical or different, represent a group comprising at least one function chosen from an isocyanate, carbamate, urea, biuret uretinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function and chosen from an aliphatic, cycloaliphatic, heterocyclic or aromatic hydrocarbon group, preferably an aliphatic hydrocarbon group comprising at least one function chosen from an isocyanate, carbamate, urea, biuret uretinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function.

[0070] By blocked isocyanate function is meant any isocyanate function having reacted with an isocyanate function blocking agent. The different blocking reactions are reversible and the unblocking conditions are known to those skilled in the art.

[0071] According to the invention, the allophanate (bl) can be a homo-allophanate, R3 and R4 being identical, or the allophanate (bl) can be a mixed allophanate, R3 and R4 being different.

[0072] According to the invention, the coating composition may comprise a mixture of different allophanates (bl) of general formula (VI).

[0073] The mixture of allophanates (bl) may comprise at least 25% by mass, advantageously at least 33% by mass, preferably at least 50% by mass of at least one monoallophanate.

[0074] The mixture of allophanates (bl) may also comprise at least one allophanate chosen from a bis-allophanate, a tris-allophanate, one or more oligomers of allophanates, as well as, to a minor extent, isocyanate carbamate resulting from the reaction of compounds of formula R4NCO and alcohol of formula R5OH or isocyanate carbamate resulting from the reaction of compounds of formula R3NCO and alcohol of formula R5OH or the mixture of isocyanate carbamates resulting from the reaction of compounds of formula R4NCO and formula R3NCO and alcohol of formula R5OH.

[0075] According to the invention, compound (b2) is a polyfunctional isocyanate, preferably a polyfunctional isocyanate of general formula (VIII):

[0076] [Chem 8]

[0077] in which

[0078] R6, R7 and R8 independently represent a hy- group carbon or an aliphatic, cycloaliphatic, heterocyclic or aromatic heterocarbon group, comprising at least one function chosen from an isocyanate, carbamate, urea, biuret, uretinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function,

[0079] p represents an integer chosen from 0, 1 or 2;

[0080] Y represents a group chosen from an isocyanurate group of formula (Yi), an imino oxadiazine dione group of formula (Y2), an oxadiazine trione group of formula (Y3), a biuret group of formula (Y4) or a group of formula (Y5):

[0081] [Chem 9]

[0082] in which

[0083] R9 independently represents a hydrogen atom, a hydrocarbon group, a C1-C20 hydrocarbon group, a heterocarbon group comprising at least one heteroatom chosen from O, N, S, Si, a C1-C20 heterocarbon group comprising at least one heteroatom chosen from O, N, S, Si;

[0084] q represents an integer chosen from 3 or 4;

[0085] Rio represents a group chosen from a hydrocarbon group, an alkyl group, a heterocarbon group, an aliphatic, cycloaliphatic, heterocyclic or aromatic heterocarbon group, comprising a function chosen from an isocyanate, carbamate, urea, biuret, uretinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function, a group derived from pentaerythritol, a group derived from trimethylolpropane.

[0086] Preferably Y in the general formula (VIII) is an isocyanurate group (Y0 or biuret (Y4).

[0087] In particular, the polyfunctional isocyanate (b2) can be:

[0088] a polyisocyanate isocyanurate (Y0 resulting from a tricondensation reaction or

[0089] a polyisocyanate (Y4) comprising between 1 and 99% by weight of biuret, preferably between 2 and 75% by weight of biuret or

[0090] a polyisocyanate isocyanurate (Y0) resulting from a tricondensation reaction and a po lyisocyanate (Y4) comprising between 1 and 99% by weight of biuret or preferably between 2 and 75% by weight of biuret.

[0091] More preferably, the polyfunctional isocyanate (b2) a group containing an isocyanurate unit or a biuret unit or a mixture of these units in which the units are obtained from the oligomerization of the following compounds: hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), bis(4,4'-isocyanatocyclohexyl)methane, 1,4-cyclohexylene diisocyanate, 1,3-bis(isocyanatomethyl)benzene (XDI), 1,3bis(2-isocyanatoprop-2-yl)benzene, 1,4bis(2-isocyanatoprop-2-yl)benzene (TMXDI), norbornane diisocyanate (NBDI), hydroxylene diisocyanate (HgXDI), 1,4-cyclohexyl diisocyanate (H6PPDI), 1,5-pentane diisocyanate (PDI) and / or dicyclohexylmethane diisocyanate.

[0092] Additive (c) is preferably chosen from: a wetting agent, a dispersant, a matting agent, an anti-foaming agent, a thickener, a molecular sieve, an elastomer, a pigment, a surfacing agent and a coalescing agent.

[0093] The quantity of additives (c) added can vary in proportions known to those skilled in the art.

[0094] The invention also relates to a process for preparing a composition comprising the following steps:

[0095] preparation of at least one polyaspartic ester (a),

[0096] preparation of at least one isocyanate compound (b),

[0097] optionally the preparation of at least one additive (c),

[0098] mixture of the preparations obtained in steps 1 and 2 and optionally 3.

[0099] In particular, the process for preparing a composition comprising the following steps:

[0100] preparation of at least one polyaspartic ester (a),

[0101] preparation of at least one isocyanate compound (bl) and at least one compound isocyanate (b2),

[0102] optionally preparation of at least one additive (c),

[0103] mixture of the preparations obtained in steps 1 and 2 and optionally 3.

[0104] Preferably, compounds (b1) and (b2) are previously mixed together before being mixed with the other compounds (a) and optionally the compounds (c).

[0105] Preferably, the preparation of compound (a) is mixed beforehand with the preparation of the additive(s) (c) before being mixed with the isocyanate compounds (bl) and (b2).

[0106] The different preparations of compounds (a), (b) and optionally (c) or (a), (bl), (b2) and optionally (c) can be carried out in any order.

[0107] Another object of the invention is the use of a composition as an adhesive coating or as a protective coating for a substrate or a coated substrate.

[0108] Another object of the invention is an adhesive coating or a protective coating of a substrate or coated substrate comprising a composition.

[0109] Preferably, the substrate or the coated substrate according to the invention is a floor, a roof, a waterproofing membrane, a wind turbine mast, an aircraft wing, a rotor blade, a propeller blade or a turbine blade.

[0110] Examples: [YES] Materials:

[0112] Feiyang F420 is a polyaspartic acid ester resin consisting of aliphatic rings substituted with secondary amines. This resin is similar to Desmophen NH-1420 resins and Teraspartic 277.

[0113] Feiyang F420 Features:

[0114] Amine equivalent (g / mol): 277

[0115] Dynamic viscosity at 25 °C: 1000-1500 mPa.s

[0116] Density: 1.06

[0117] Feiyang F520 is a polyaspartic acid ester resin consisting of aliphatic rings substituted with secondary amines. This resin is similar to Desmophen NH-1520 resins and Teraspartic 292.

[0118] Feiyang F520 Features:

[0119] Amine equivalent (g / mol): 290

[0120] Dynamic viscosity at 25 °C: 1200-1500 mPa.s

[0121] Density: 1.06

[0122] Tolonate HDT is an isocyanurate-type polyisocyanate prepared from hexamethylenediisocyanate.

[0123] Tolonate HDT Characteristics:

[0124] NCO functionality: 21.5 - 22.5%,

[0125] Dynamic viscosity (at 25 °C): 2000 - 2800 mPa.s,

[0126] Density (at 25°C): 1.16

[0127] Tolonate HDT-LV is an isocyanurate type polyisocyanate prepared from hexamethylenediisocyanate.

[0128] Tolonate HDT-LV Characteristics:

[0129] NCO functionality: 22 - 24%,

[0130] Dynamic viscosity (at 25 °C): 900 - 1500 mPa.s,

[0131] Density (at 25°C): 1.16

[0132] Tolonate HDB is a biuret-type polyisocyanate prepared from hexamethylenediisocyanate.

[0133] Tolonate HDB Characteristics:

[0134] NCO functionality: 21 - 23%,

[0135] Dynamic viscosity (at 25 °C): 7000 - 11000 mPa.s,

[0136] Density (at 25°C): 1.12

[0137] Tolonate HDB-LV is a biuret-type polyisocyanate prepared from hexamethylenediisocyanate.

[0138] Tolonate HDB-LV Characteristics:

[0139] NCO functionality: 22.5 - 24.5%,

[0140] Dynamic viscosity (at 25 °C): 1500 - 2500 mPa.s,

[0141] Density (at 25°C): 1.12

[0142] Tolonate X-FLO 100 is an allophanate type polyisocyanate prepared from hexamethylenediisocyanate.

[0143] Tolonate X-FLO 100 Features:

[0144] NCO functionality: 11.3 - 13.3%,

[0145] Dynamic viscosity (at 25 °C): 60-220 mPa.s,

[0146] Density (at 25°C): 1.04

[0147] Silosiv A3 is an additive serving as a molecular sieve.

[0148] Tego Airex 944 is an additive used as an anti-foaming agent.

[0149] BYK 378 is an additive serving as a surfactant.

[0150] All additives, polyisocyanates and resins used in the examples are commercially available products.

[0151] Example 1: Preparation of compositions (A)

[0152] In order to prepare the compositions (A), the different products are weighed according to the proportions indicated in Table 1 and then mixed using a Speedmixer until the mixture is homogenized.

[0153] Table 1 describes the proportions of each polyaspartic resin and additive as a function of each composition A.

[0154] [Tables 1] Compositions (A) Al (% by mass) A2 (% by mass) Feiyang F420 95.6 66.9 Feiyang F520 0 28.7 Silosiv A3 1.9 1.9 Tego Airex 944 1.8 1.8 BYK 378 0.7 0.7

[0155] Example 2: Preparation of polyisocyanate compositions (B)

[0156] In order to produce the compositions (B), the mixtures are prepared according to the proportions described in Table 2. The polyisocyanate mixtures (B) are then homogenized for at least one night on a rolling pot.

[0157] The NCO titer is measured by titration of the -NCO functions of each compound using a back titration of dibutylamine with a hydrochloric acid solution.

[0158] Viscosity is measured at 25°C using an Anto-Paar cone-plate viscometer with an angle of 2°. The shear rate during measurement varies from 0.1 to 100 s 1 with a rise and fall in the shear rate.

[0159] A low viscosity will be defined by a viscosity lower than 1500 mPa.s and a sufficient NCO title is defined by a value higher than 13%.

[0160] Table 2 shows the proportions of polyisocyanates, the viscosity and the NCO titer as a function of each composition B.

[0161] [Tables2] Compositions (B) HDT (%) HDT-L V(%) HDB (%) HDB-L V(%) XFlo 100 (%) Viscosity at 25 °C (mPa.s) NCO Title (%) B1 15 85 170 13.8 B2 40 60 365 16.2 B3 (comp.) 100 0 2400 22.0 B4 15 85 234 13.9 B5 40 60 323 16.6 B6 (comp.) 100 0 1200 23.0 B7 15 85 190 13.8 B8 25 75 260 14.7 B9 40 60 460 16.2 B10 (comp.) 100 0 9000 22.0 Bll 15 85 221 13.9 B12 40 60 393 16.6 B13 (comp.) 100 0 2000 23.0

[0162] As specified in Table 2, compositions B3, B6, B10 and B13 comprise 100% of each isocyanate. These are comparative examples.

[0163] The results show a decrease in viscosity with increasing quantity of Tolonate X-FLO 100 in composition (B) used. The use of a proportion of Tolonate X-FLO 100 greater than or equal to 60% makes it possible to obtain compositions (B) whose viscosity is less than 1500 mPa.s at 25°C and with an NCO titre greater than 13%.

[0164] The comparative examples, although having an NCO titre greater than 13%, have a viscosity greater than 1500 mPa.s apart from example B6.

[0165] Example 3: Elongation of the compositions

[0166] The elongation is measured on coatings resulting from the mixture between the compositions (A) and the polyisocyanates (B) described in examples 1 and 2. This mixture is carried out using a Speedmixer in order to ensure good homogeneity, the formulations thus obtained are then crosslinked for 7 days in an enclosure regulated at 23°C and 50% humidity. The mixing ratio between the compositions (A) and (B) is defined by an NH / NCO ratio which is equimolar, i.e. constant and equal to 1. The NH functionalities being present in the compositions (A) and the NCO functionalities being present in the polyisocyanates (B).

[0167] The elongation measurements are carried out using a tensile testing machine (MTS) on standardized format specimens (type 5A specimen of the ISO 527-2 standard) with a thickness between 1 and 2 mm. The tensile speed is set at 10 mm / min.

[0168] The elongation at break corresponds to the elongation value reached when the specimen breaks. The sample is considered to have improved flexibility properties from an elongation at break greater than 50%.

[0169] Table 3 shows the elongation at break results for the different compositions A and B.

[0170] [Tables3] Compositions (A) Compositions (B) Elongation (%) Al B1 145 B2 110 B3 (comp.) <20 B4 389 B5 55 B6 (comp.) <20 B7 401 B8 230 B9 81 B10 (comp.) - Bll 470 B12 69 B13 (comp.) <20 A2 B1 642 B2 219 B3 (comp.) <20 B4 777 B5 188 B6 (comp.) <20 B7 600 B8 405 B9 230 B10 (comp.) - Bll 647 B12 162 B13 (comp.) <20

[0171] As specified in Table 3, the compositions comprising the polyisocyanate mixtures B3, B6, B10 and B13 are comparative examples. These examples include: The compounds are distinguished by their low flexibility (elongation at break well below 50%). Example B6, which had a low viscosity, however, did not allow sufficient elongation at break (> 50%) to be obtained. Elongation measurements in the mixtures containing composition B10 could not be carried out due to the viscosity of the mixture being too high to be applied properly.

[0172] From a mass proportion of Tolonate X-FLO 100 in composition (B) greater than or equal to 60%, the composition has improved flexibility. The effect is all the more marked with the use of a mixture containing composition (A2).

Claims

Claims

1. Coating preparation composition comprising: at least one polyaspartic ester compound (a), at least one isocyanate compound (b), optionally at least one additive (c), wherein - the polyaspartic ester (a) is obtained by the Michael reaction of a system comprising a polyamine and an ester, - the isocyanate compound (b) is a mixture of isocyanates comprising: at least one allophanate (bl) and at least one polyfunctional isocyanate (b2) and wherein the mass ratio (bl) / (b2) is between 55 / 45 and 99 / 1, said isocyanate (b) has an NCO titre greater than 13% and a viscosity less than 1500 mPa.s at 25°C, the molar ratio between the mixtures (a) and (b) is defined by the number of NH functions for (a) and the number of NCO functions for (b) being between 0.7 and 1.

3.

2. A composition according to claim 1 wherein the polyaspartic ester (a) is a polyaspartic ester according to the general formula (I): [Chem 1] wherein X represents an aliphatic chain or a polyether chain, R1 and R2 are, independently of each other, an organic group which is inert towards an isocyanate group at normal atmospheric pressure and at 100°C or less, n represents an integer greater than or equal to 2.

3. The composition of claim 2 wherein the aliphatic residue X is composed of one or more of the following residues: a polyether residue, a linear alkyl residue, a branched alkyl residue and a cycloalkyl residue.

4. Composition according to claim 1 or 3 in which the polyaspartic ester(s) (a) of general formula (I) are one or more polyaspartic esters or a mixture of polyaspartic esters: of general formula (II) and / or [Chem 2] of general formula (III) and / or [Chem 3] of general formula (IV) [Chem 4] of general formula (V) [Chem 5] in which the groups Ri and R2 are, independently of each other, a C1-C10 alkyl group and u is an integer between 1 and 10.

5. Composition according to any one of claims 1 to 4 in which the allophanate (bl) has an NCO functionality equal to 2.1 ± 0.3 and has a general formula (VI): [Chem 6] in which R3 and R4, which may be identical or different, represent a hydrocarbon group chosen from an isocyanate, carbamate, urea, biuret uretinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function, R5 represents the remainder of a molecule comprising an OH function after reaction of this OH with an isocyanate function and the molecule of which with the OH group may also comprise an ether or polyether function and chosen from a silanol, a linear chain aliphatic monoalcohol in C12-C20, a branched chain aliphatic monoalcohol in C12-C20,a C2-C40 straight-chain diol or a C3-C40 branched-chain diol of which at least one of the hydroxyl groups is substituted and which is of general formula (VII): [Chem 7] in which Ti represents a CrC2o straight-chain alkyl group, a CrC2o branched alkyl group, a group of formula T3-CO-CH3 in which T3 represents a CrC2o straight-chain alkyl group or a C1-C20 branched alkyl group; T2 represents a hydrogen or an alkyl group or an ether group of formula -CH2OT4 in which T4 represents a hydrocarbon chain and m represents an integer ranging from 1 to 50.,

6. Composition according to any one of claims 1 to 5 in which the compound (b2) is a polyfunctional isocyanate of general formula (VIII): [Chem 8] in which R6, R7 and R8 represent, independently of each other, a hydrocarbon group or an aliphatic heterocarbon group, cycloaliphatic, heterocyclic or aromatic, comprising at least one function chosen from an isocyanate, carbamate, urea, biuret uretinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function, p represents an integer chosen from 0, 1 or 2; Y represents a group selected from an isocyanurate group of formula (YJ, an imino oxadiazine dione group of formula (Y2), an oxadiazine trione group of formula (Y3), a biuret group of formula (Y4) or a group of formula (Y5): [Chem 9 ] in which R9 independently represents a hydrogen atom, a hydrocarbon group, a CrC2o hydrocarbon group, a hetero-carbon group comprising at least one heteroatom selected from O, N, S, Si, a C1-C20 heterocarbon group comprising at least one heteroatom selected from O, N, S, Si; q represents an integer selected from 3 or 4;Rio represents a group chosen from a hydrocarbon group, an alkyl group, a heterocarbon group, an aliphatic, cycloaliphatic, heterocyclic or aromatic heterocarbon group, comprising a function chosen from an isocyanate, carbamate, urea, biuret, uretinedione, acylurea, isocyanurate, blocked isocyanate, allophanate function, a group derived from pentaerythritol, a group derived from trimethylolpropane.;

7. Composition according to claim 6, in which the group Y is an isocyanurate (YJ) or biuret (Y4) group.

8. Composition according to any one of claims 1 to 7 in which the additive (c) is chosen from: a wetting agent, a dispersant, a matting agent, an anti-foaming agent, a thickener, a molecular sieve, an elastomer, a pigment, a surfacing agent and a coalescing agent.

9. A process for preparing a composition according to any one of claims 1 to 8 comprising the following steps:

1. preparation of at least one polyaspartic ester (a), 2. preparation of at least one isocyanate compound (b), the isocyanate compound (b) is a mixture of isocyanates comprising at least one allophanate (bl) and at least one polyfunctional isocyanate (b2) and in which the mass ratio (bl) / (b2) is between 55 / 45 and 99 / 1, said isocyanate (b) has an NCO titre greater than 13% and a viscosity less than 1500 mPa.s at 25 °C, the molar ratio between the mixtures (a) and (b) is defined by the number of NH functions for (a) and the number of NCO functions for (b) being between 0.7 and 1.3, 3. optionally the preparation of at least one additive (c), mixture of the preparations obtained in steps 1 and 2 and optionally

10. Use of a composition according to any one of claims 1 to 8 as an adhesive coating or as a protective coating for a substrate or a coated substrate.

11. An adhesive coating or a protective coating for a substrate or coated substrate comprising a composition according to any one of claims 1 to 8.

12. A coating according to claim 11, wherein the substrate or coated substrate according to the invention is a floor, a roof, a waterproofing membrane, a wind turbine mast, an aircraft wing, a rotor blade, a propeller blade or a turbine blade.