Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
  • C09D175/04—Polyurethanes
  • C09D175/08—Polyurethanes from polyethers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/08—Processes
  • C08G18/0838—Manufacture of polymers in the presence of non-reactive compounds
  • C08G18/0842—Manufacture of polymers in the presence of non-reactive compounds in the presence of liquid diluents
  • C08G18/0847—Manufacture of polymers in the presence of non-reactive compounds in the presence of liquid diluents in the presence of solvents for the polymers
  • C08G18/0852—Manufacture of polymers in the presence of non-reactive compounds in the presence of liquid diluents in the presence of solvents for the polymers the solvents being organic
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/30—Low-molecular-weight compounds
  • C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
  • C08G18/3203—Polyhydroxy compounds
  • C08G18/3218—Polyhydroxy compounds containing cyclic groups having at least one oxygen atom in the ring
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/48—Polyethers
  • C08G18/4854—Polyethers containing oxyalkylene groups having four carbon atoms in the alkylene group
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
  • C08G18/72—Polyisocyanates or polyisothiocyanates
  • C08G18/721—Two or more polyisocyanates not provided for in one single group C08G18/73 - C08G18/80
  • C08G18/725—Combination of polyisocyanates of C08G18/78 with other polyisocyanates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
  • C08G18/72—Polyisocyanates or polyisothiocyanates
  • C08G18/74—Polyisocyanates or polyisothiocyanates cyclic
  • C08G18/75—Polyisocyanates or polyisothiocyanates cyclic cycloaliphatic
  • C08G18/751—Polyisocyanates or polyisothiocyanates cyclic cycloaliphatic containing only one cycloaliphatic ring
  • C08G18/752—Polyisocyanates or polyisothiocyanates cyclic cycloaliphatic containing only one cycloaliphatic ring containing at least one isocyanate or isothiocyanate group linked to the cycloaliphatic ring by means of an aliphatic group
  • C08G18/753—Polyisocyanates or polyisothiocyanates cyclic cycloaliphatic containing only one cycloaliphatic ring containing at least one isocyanate or isothiocyanate group linked to the cycloaliphatic ring by means of an aliphatic group containing one isocyanate or isothiocyanate group linked to the cycloaliphatic ring by means of an aliphatic group having a primary carbon atom next to the isocyanate or isothiocyanate group
  • C08G18/755—Polyisocyanates or polyisothiocyanates cyclic cycloaliphatic containing only one cycloaliphatic ring containing at least one isocyanate or isothiocyanate group linked to the cycloaliphatic ring by means of an aliphatic group containing one isocyanate or isothiocyanate group linked to the cycloaliphatic ring by means of an aliphatic group having a primary carbon atom next to the isocyanate or isothiocyanate group and at least one isocyanate or isothiocyanate group linked to a secondary carbon atom of the cycloaliphatic ring, e.g. isophorone diisocyanate
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
  • C08G18/72—Polyisocyanates or polyisothiocyanates
  • C08G18/77—Polyisocyanates or polyisothiocyanates having heteroatoms in addition to the isocyanate or isothiocyanate nitrogen and oxygen or sulfur
  • C08G18/78—Nitrogen
  • C08G18/79—Nitrogen characterised by the polyisocyanates used, these having groups formed by oligomerisation of isocyanates or isothiocyanates
  • C08G18/791—Nitrogen characterised by the polyisocyanates used, these having groups formed by oligomerisation of isocyanates or isothiocyanates containing isocyanurate groups
  • C08G18/792—Nitrogen characterised by the polyisocyanates used, these having groups formed by oligomerisation of isocyanates or isothiocyanates containing isocyanurate groups formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G2150/00—Compositions for coatings

Definitions

• the present invention relates to a crosslinkable composition for forming a polyurethane coating on different types of substrates.
• the present invention relates to a polyurethane composition having a high content of biosourced monomers comprising isosorbide as a chain extender diol and a trimer of pentamethylene diisocyanate and the polyurethane coating obtained therefrom.
• compositions for forming coatings on substrates may be for example protective coatings, decorative, or surface treatment.
• polyurethanes make it a material of choice for coatings. With a very wide range of hardness, very good resistance to shocks and cracking and very good chemical resistance, they are suitable for coating all types of surfaces.
• a crosslinked polyurethane coating is conventionally obtained by reacting a long chain polyol, a short chain diol and a polyisocyanate.
• Various compounds are described in the literature for each of these reagents.
• at least one of the two mixtures, either the polyol mixture or the polyisocyanate mixture has a functionality greater than two in order to obtain a network.
• the level of compounds of functionality greater than or equal to 2 makes it possible to adapt the crosslinking density and is thus one of the solutions to adapt the properties of the network.
• the polyisocyanate is generally an aliphatic polyisocyanate or a mixture of aliphatic polyisocyanates having -NCO functionality strictly greater than 2 when used with polyols of average functionality equal to two.
• -NCO functionality strictly greater than 2 provides a crosslinked polyurethane.
• the long chain polyol is generally a polyether polyol type diol or a polyester polyol or a polycarbonate polyol which may in particular have a molecular weight of 400 to 4000 g / mol.
• the short chain diol also called chain extender diol, is generally 1,4-butanediol.
• the long chain polyol imparts flexibility to the polyurethane coating.
• the short chain diol contributes to the hardness of the coating with the polyisocyanate.
• a polyurethane coating traditionally has a single glass transition temperature (Tg). Indeed, a coating obtained with a material having a phase segregation would have a white color related to the heterogeneity of the material, these different phases resulting in optical phenomena that make the material opaque.
• Tg of a polyurethane coating is greater than or equal to 30 ° C so as not to give it tack in the usual conditions of use.
• the Applicant has discovered that the use of isosorbide and pentamethylene diisocyanate trimer improved the properties of the resulting polyurethane coating, in particular substrate adhesion, impact resistance and folding resistance.
• the use of isosorbide makes it possible to increase the Tg and the rigidity of the coating with respect to the same coating obtained with BDO.
• the polyurethane coating obtained with the composition of the present invention also has the advantage of having a high content of biosourced monomers since the isosorbide is a fully biobased product and the pentamethylene diisocyanate trimer is a product partially derived from biosourced material.
• the pentamethylene diisocyanate trimer has a lower volatility than the diisocyanate monomers. Thus, its handling is less risky and the replacement of diisocyanate monomers with a trimer of pentamethylene diisocyanate will decrease the toxicity of a non-crosslinked polyurethane composition.
• composition comprising:
• a polyol fraction comprising a polyol chosen from a polyester polyol, a polyether polyol, a polycarbonate polyol or a mixture thereof, the said polyol being a diol or a mixture of diols;
• a polyisocyanate moiety comprising a trimer of pentamethylene diisocyanate
• Another object of the invention is a method of manufacturing a polyurethane coating on a substrate which comprises the following steps:
• the invention also relates to a polyurethane coating that can be obtained by the process according to the invention.
• the present invention relates to a crosslinkable polyurethane coating composition.
• crosslinkable composition for a polyurethane coating is intended to mean a composition capable of providing a polyurethane coating after crosslinking the composition.
• polyurethane coating is intended to mean a crosslinked polyurethane deposited on a solid substrate in the form of a thin layer, for example a layer having a thickness of 20 to 500 microns, in particular 20 ⁇ . , 50 ⁇ , 100 ⁇ , 150 ⁇ , 200 ⁇ , 250 ⁇ , 300 ⁇ , 350 ⁇ , 400 ⁇ or 450 ⁇ . It may be for example protective coatings, decorative, or surface treatment. Protective films, varnishes and paints are coatings within the meaning of the present invention.
• crosslinking is understood to mean the formation of one or more three-dimensional networks by creating chemical bonds between the polymer chains.
• a polymer can be crosslinked when comprises a monomer unit having more than 2 reactive functions in polymerization.
• the crosslinked polyurethane of the invention is obtained by introducing into the polyurethane coating composition a trimer of pentamethylene diisocyanate.
• the crosslinking can in particular be carried out under the action of heat or by irradiation with a UV beam, optionally in the presence of a catalyst.
• the crosslinkable polyurethane coating composition according to the invention is distinguished from a thermoplastic polyurethane (TPU) composition and a polyurethane adhesive composition.
• TPU thermoplastic polyurethane
• the polyurethane coating obtained by crosslinking the composition according to the invention has a single glass transition temperature (Tg), said Tg being greater than or equal to 20 ° C, preferably greater than or equal to 25 ° C, more preferably higher or equal to 30 ° C.
• Tg glass transition temperature
• the Tg of the polyurethane coating obtained by crosslinking the composition according to the invention may in particular be measured by dynamic mechanical analysis or differential scanning calorimetry.
• composition according to the invention comprises isosorbide.
• Isosorbide is used as the chain extender diol.
• Isosorbide is a cycloaliphatic diol corresponding to the formula:
• isosorbide as used in the present application encompasses all the stereoisomers (ie the enantiomers or diastereoisomers) of the isosorbide, that is to say among others the isoidide and the isomannide.
• Polyol fraction ie the enantiomers or diastereoisomers
• composition according to the invention comprises a polyol fraction.
• the polyol moiety comprises or consists of a polyol or a mixture of polyols.
• polyol means a compound having an OH functionality greater than or equal to 2.
• polyol therefore includes diols and triols. Isosorbide is not considered as a polyol within the meaning of the present invention.
• -OH functionality is meant in the sense of the present invention, the total number of reactive hydroxyl functions per molecule of compound.
• the -OH ( OH ) functionality can be calculated from the hydroxyl number (I OH ), and the number average molar mass of the polyol (Mn po iyoi) according to the following formula:
• the hydroxyl number can be measured by acetylation followed by a back titration with potash according to ISO 14900: 2001, Plastics - Polyols for the production of polyurethane - Determination of the hydroxyl number.
• the hydroxyl number is expressed in mg KOH / g which corresponds to the amount of KOH in mg which is necessary to neutralize 1 g of polyol.
• the polyol moiety comprises or consists of a diol or a mixture of diols.
• the polyol moiety may further comprise a triol.
• the polyol fraction comprises or consists of a mixture of diols and triols.
• the polyol of the polyol fraction may in particular have a molecular weight of between 400 and 4000 g / mol, preferably between 500 and 2000 g / mol and more preferably between 600 and 1500 g / mol.
• the polyol of the polyol moiety is a polyester polyol or a polyether polyol or a polycarbonate polyol.
• the polyester polyol, polyether polyol and polycarbonate polyol are preferably linear polyols which may contain aliphatic, alicyclic or heterocyclic monomer units.
• linear polyol means a polyol which does not comprise a side chain having a reactive function for the polymerization.
• the polyether polyol also called polyalkylene ether polyol, is preferably a linear polyether having two terminal hydroxyl functions.
• the alkylene portion can comprise 2 to 10 carbon atoms, preferably 2 to 4 carbon atoms. It may especially be obtained by opening a cyclic ether, such as an epoxide, with a glycol.
• the polyether polyols according to the present invention comprise block or random glycol copolyethers, in particular block or random copolymers of ethylene oxide and of propylene oxide.
• polyether polyols are polyethylene glycol (PEG), polypropylene glycol (PPG), poly (oxyethyleneoxypropylene) glycol, polytetramethylene ether glycol (PTMEG) or a mixture thereof.
• the polyester polyol is preferably a linear polyester having two terminal hydroxyl functions. He can be obtained by linear condensation of at least one glycol with at least one dicarboxylic acid or by reaction of a cyclic ester with a glycol.
• Polyester polyols according to the present invention comprise block or random glycol copolyesters, such copolyesters polyols may in particular be obtained by using a mixture of at least two glycols and / or at least two dicarboxylic acids.
• the glycols used may comprise 2 to 8 carbon atoms, preferably 2 to 6 carbon atoms, such as ethylene glycol, propylene glycol, 1,3-propanediol, butylene glycol, 1,4-butanediol and 1,6-hexanediol.
• the dicarboxylic acids used generally have 4 to 10 carbon atoms, such as succinic acid, glutamic acid, glutaric acid, octanedioic acid, sebacic acid, maleic acid, fumaric acid, adipic acid, azelaic acid, phthalic acid, isophthalic acid and terephthalic acid.
• the dicarboxylic acid used may be a dicarboxylic fatty acid, that is to say a saturated or unsaturated aliphatic dicarboxylic acid comprising from 8 to 44 atoms between the acid functional groups which may for example be synthesized by dimerization of unsaturated aliphatic monocarboxylic acids or unsaturated aliphatic esters having 8 to 22 carbon atoms such as linoleic acid and linolenic acid.
• the cyclic ester used is usually epsilon-caprolactone.
• polyester polyols are polytetechelic polyesters of poly (ethylene adipate), poly (propylene adipate), poly (propylene-co-ethylene adipate), poly (butylene adipate), poly (ethylene-co-butylene) polyesters. adipate), poly (caprolactone) diol, copolymers of caprolactone and lactide, or a mixture thereof.
• the polycarbonate polyol is preferably a linear polycarbonate having two terminal hydroxyl functions. he can be obtained by linear condensation of at least one glycol with at least one alkyl carbonate derivative or phosgene. It can also be obtained by reaction between propylene oxide and CO 2 .
• the polycarbonates polyols according to the present invention comprise the block or random glycol copolycarbonates, such copolycarbonates polyols may in particular be obtained by using a mixture of at least two glycols and alkyl carbonate.
• the diols can be linear aliphatic diols, cyclic diols or heterocyclic diols.
• the polyol fraction comprises a polyol chosen from a polyethylene glycol (PEG), a polypropylene glycol (PPG), a polytetramethylene ether glycol (PTMEG), a poly (caprolactone) diol or a mixture thereof; preferably a PTMEG; more preferably a PTMEG having a molecular weight of 250 to 4000, preferably 400 to 2000 g / mol.
• PEG polyethylene glycol
• PPG polypropylene glycol
• PTMEG polytetramethylene ether glycol
• a poly (caprolactone) diol or a mixture thereof preferably a PTMEG; more preferably a PTMEG having a molecular weight of 250 to 4000, preferably 400 to 2000 g / mol.
• the amount of polyol relative to the amount of isosorbide is adjusted in order to obtain a molar ratio of all the functions -OH of the polyol fraction over all of the -OH functions of the isosorbide of between 0.2 and 2, preferably between 0.3 and 1, more preferably between 0.4 and 0.6.
• composition according to the invention comprises a polyisocyanate fraction.
• the polyisocyanate moiety comprises or consists of a polyisocyanate or a mixture of polyisocyanates.
• polyisocyanate is meant, within the meaning of the present invention, a compound having a functionality -NCO greater than or equal to 2.
• the term polyisocyanate thus includes in particular diisocyanates having a functionality -NCO equal to 2, the triisocyanates having a functionality -NCO equal to 3, as well as the polyisocyanates having a -NCO functionality strictly greater than 2 and strictly less than 3.
• -NCO functionality is meant, in the sense of the present invention, the total number of reactive isocyanate functions per molecule of compound.
• the -NCO functionality can be estimated by calculation after NCO titration by back-dosing the excess dibutylamine with hydrochloric acid (according to EN ISO 14896-2006).
• the polyisocyanate moiety comprises a pentamethylene diisocyanate trimer.
• the polyisocyanate fraction of the composition according to the invention may further comprise an aliphatic diisocyanate.
• aliphatic diisocyanate is intended to mean a diisocyanate which does not contain an aromatic ring.
• the term aliphatic diisocyanate therefore includes non-cyclic aliphatic diisocyanates and cycloaliphatic diisocyanates.
• the aliphatic diisocyanate is selected from pentamethylene diisocyanate (PMDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), methylene dicyclohexyl diisocyanate (HMDI or hydrogenated MDI) or a mixture thereof; more preferably IPDI.
• the polyisocyanate fraction may in particular comprise at least 5 mol% relative to the -NCO functions, in particular at least 10 mol% relative to the -NCO functions, more particularly at least 15 mol% relative to the -NCO functions, of pentamethylene diisocyanate trimer.
• the polyisocyanate fraction of the composition according to the invention comprises:
• the total amount of polyisocyanate relative to the amount of isosorbide and polyol is adjusted in order to obtain a molar ratio of all the functions -OH of the polyol fraction and of isosorbide on all the functions -NCO the polyisocyanate fraction of between 0.8 and 1.2, preferably between 0.95 and 1.05.
• composition according to the invention may further comprise a catalyst.
• the catalyst makes it possible to accelerate the polymerization reaction and / or to increase the degree of polymerization of the polyurethane.
• catalysts examples include organic or inorganic acid salts; organometallic derivatives of bismuth, lead, tin, antimony, uranium, cadmium, cobalt, thorium, aluminum, mercury, zinc, nickel, cerium, molybdenum, vanadium, copper, manganese or zirconium; phosphines; tertiary organic amines; or a mixture thereof.
• the catalyst is dibutyltin dilaurate.
• the amount of catalyst is between 0.001 and 5%, preferably between 0.005 and 1.0% by weight relative to the total weight of the polyol fraction, the polyisocyanate fraction and the isosorbide.
• composition according to the invention may further comprise a solvent.
• the solvent is selected from 2-butanone, cyclopentanone, dimethylisosorbide (DMI) or a mixture thereof, more preferably a mixture of 2-butanone and DMI.
• the amount of solvent is between 10 and 60%, preferably between 20 and 50% by weight relative to the total weight of the formulation.
• the composition according to the invention may also comprise a spreading agent.
• the spreading agent makes it possible to obtain, before reticulation, a good spread of the composition when it is applied to the substrate.
• the spreading agent may be particularly useful in preventing crater formation in the coating by lowering the surface tension of the composition.
• An example of a spreading agent that can be introduced into the composition according to the invention is a polyether modified polydimethylsiloxane such as BYK 307 sold by BYK.
• the amount of leveling agent in the composition is from 0.01 to 0.2%, preferably 0.05 to 0.15%, by weight relative to the total weight of the polyol fraction, of the polyisocyanate fraction and isosorbide.
• composition according to the invention may also comprise other additives, for example inhibitors of polymerization, dyes, pigments, opacifiers, heat shield or ultra-violet additives, antistatic agents, antibacterial agents, anti ⁇ fouling or anti-fungal.
• additives for example inhibitors of polymerization, dyes, pigments, opacifiers, heat shield or ultra-violet additives, antistatic agents, antibacterial agents, anti ⁇ fouling or anti-fungal.
• the composition according to the invention comprises less than 10%, more preferably less than 2% by weight of these additives, relative to the weight of the composition.
• composition according to the invention may be prepared by mixing the ingredients which constitute it, in particular with stirring.
• the amount of solvent makes it possible to adjust the viscosity of the composition.
• the method of manufacturing the polyurethane coating according to the invention comprises a step of depositing on a solid substrate a layer of the composition as described above.
• the deposition of the composition may be carried out according to any means known to those skilled in the art, for example by dipping, by spin coating, by "barcoater”, by “tape casting”, by spraying or with the aid of a brush or a roll.
• the thickness of the deposited layer is adjusted according to the thickness of the coating that is desired.
• the thickness of the deposited layer may, for example, be between 100 nm and 2 mm, preferably from 100 to 500 micrometers.
• the layer has a uniform thickness, so as to obtain a uniform final coating.
• the substrate on which the coating is applied can be of any kind. It may be a particular substrate of wood, metal, plastic, glass or paper.
• the process according to the invention also comprises a step of crosslinking the composition.
• the crosslinking of the composition can in particular be done by heating.
• the heating is carried out at a temperature ranging from 100 ° C. to 250 ° C., preferably from 150 ° C. to 200 ° C.
• the temperature can be increased in temperature increments or by using a temperature ramp.
• the duration of the heating may especially be between 1h and 5h, preferably between 1h30 and 3h.
• Heating can also be carried out under vacuum.
• the process according to the invention makes it possible to obtain a polyurethane coating having advantageous properties.
• the coatings obtained may have at least one of the following properties:
• the resulting coatings which are also objects of the present invention possess properties at least as good, if not better, than currently available coatings obtained with 1,4-butanediol as the chain extender diol.
• the invention will be better understood in the light of the following nonlimiting and purely illustrative examples.
• polyol poly (tetramethylene glycol) of molecular weight 650 g / mol (PTMEG 650) or 1000 g / mol (PTMEG 1000) (Sigma-Aldrich)
• polyisocyanate trimer of pentamethylene diisocyanate (t-PMDI) (Covestro)
• IPDI isophorone diisocyanate
• BDO 1,4-butanediol
• DBTDL dibutyltin dilaurate
• Various compositions were prepared by mixing the monomers indicated in the table below with stoichiometry (-OH polyol) / (-NCO polyisocyanate + diisocyanate) / (-OH extender of the chain) of 1 / 3.05 / 2.
• the monomers ie polyol, diisocyanate, polyisocyanate and chain extender
• a solvent mixture comprising 2-butanone and dimethylisosorbide (volume ratio 1: 5) so as to obtain a concentration of 70% by weight of the monomers relative to the weight of the composition.
• the additive BYK 307 is added to reduce the crater effects to a percentage of 0.1% by weight relative to the weight of the monomers.
• the DBTDL catalyst is added at a percentage of 0.025% by weight with respect to weight of the monomers to accelerate the reaction (except for the formulation CEX1 which gelled before application).
• a thin layer of crosslinkable composition as described above was deposited on steel plates (standardized Q-panel R44) using a Sheen Instruments 1133N bar-coater, equipped with a 150 ⁇ m bar to to cover the entire surface of the support with the minimum of composition.
• composition is then crosslinked in a vacuum oven under a vacuum of 100 mbar following the following thermal cycle:
• Impact resistance (1kg to 1m ball) The impact resistance measurements were carried out according to ISO 6272: Paints and varnishes - Rapid deformation tests (impact resistance) - Part 1: Drop test of a mass with a large surface penetrator. Adherence (grid test)
• the folding tests were carried out by folding the support at 90 ° (coating on the inside and outside). The resistance of the coating was then evaluated qualitatively at the fold.
• Tg expressed in degrees Celsius (° C)
• ° C degrees Celsius

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Polymers & Plastics (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Life Sciences & Earth Sciences (AREA)
• Materials Engineering (AREA)
• Wood Science & Technology (AREA)
• Polyurethanes Or Polyureas (AREA)
• Paints Or Removers (AREA)

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• 2017
  • 2017-10-27 FR FR1760156A patent/FR3072963B1/fr active Active
• 2018
  • 2018-10-26 EP EP18800736.3A patent/EP3700955A1/fr active Pending
  • 2018-10-26 KR KR1020207011646A patent/KR20200074124A/ko not_active Application Discontinuation
  • 2018-10-26 JP JP2020523349A patent/JP7253544B2/ja active Active
  • 2018-10-26 US US16/759,123 patent/US20200339835A1/en active Pending
  • 2018-10-26 WO PCT/FR2018/052665 patent/WO2019081868A1/fr unknown

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