MXPA01009224A - Cross-linked acrylic microparticles, method for the production thereof and use thereof in coverings and moulding products - Google Patents

Abstract

The invention relates to cross-linked acrylic microparticles, a method for the production thereof by polymerization in a dispersion in a non aqueous medium and to the uses thereof in covering or moulding compositions involving a favourable compromise between hardness, flexibility and adhesion. The micropparticles are obtained from a composition comprising:50-99%mols of a constitutent (A) consisting of Cardura E 10 (meth)acrylate and optionally alkyl (meth)acrylate in C2-C8;a compound (B) consisting of at least one monomer or oligomer having at least 2 ethylenic unsaturations;a compound (C) consisting of at least one monomer or oligomer having in addition to one ethylenic unsaturation at least one second function (F1) with the possibility of at least partial chemical modification of the initial functions f1 into final functions f2.

Description

"RETICULATED ACRYLIC MICROPARTICLES5, PROCESS FOR PREPARING AND USING THEM IN COATINGS AND PRODUCTS TO MOLD " This invention relates to cross-linked acrylic microparticles of specific composition, with a preparation process by dispersion polymerization in a non-aqueous medium in the absence of a stabilizing polymer, and with the applications in the coating or molding compositions as reactive or non-reactive allowing, by virtue of its presence, improved performance qualities in terms of a compromise between hardness, flexibility and adhesion to various substrates, without adversely affecting the other essential operating qualities of coatings or related molding products, or the implementation of the same. These microparticles and the compositions containing them can be used in various fields of application such as: protective varnishes, paints, adhesives, inks, powders for molding, products for molding charged or uncharged, and compositions that require significantly improved performance qualities both in terms of hardness, flexibility and adhesion to various substrates.

- - The compromise of a common property for a material, either this or a coating or a product for molding or a compound, is always difficult to obtain, in particular a good compromise of hardness / flexibility / adhesion. A known method for improving the hardness / flexibility compromise is to incorporate a softer additive into a hard matrix, or vice versa. For example, brittle matrices of the epoxy / aa type can be reinforced by adding thermoplastic or elastomeric particles of the core hull type as described in "Toughened Plastics" Adv. Chem. Series Number 252 (1966) Ed. CK. Riew and AJ Kinlock, Am. Chem. Soc., Washington DC. The main inconvenience of this solution is a very considerable increase in the viscosity of the formulations, which imposes problems of molding or use as a coating. In the case of coatings, in order to increase the hardness, the common practice is to incorporate multifunctional crosslinking agents into the formulation in order to increase the density of crosslinking of the film. The addition of these agents involves an increase in the internal constraints and heterogeneity of the matrix (Macromol, Chem. Phys., 1998, 1043-1049) and, consequently, a decrease in the flexibility and adhesion of the coating. The use of microparticles in - - coatings is already known in Prog. Org. Coat., 15, 1988, 373 to improve the mechanical properties of the coating. However, the increase in breaking stress is achieved at the expense of material flexibility. In addition, no effect on adhesion is described. Specifically, the adhesion is also a key property for coatings and for molding compositions reinforced with fillers or fillers. A general description of the adhesion phenomenon is provided in the Adhesion Manual (D.E. Packham, Longman Scientific &Technical, 1992). Adhesion depends, on the one hand, on the interactions between the substrate and the molecules in the coating, and, on the other hand, on the mechanical properties of the coating. Generally, in a homologous series of chemical composition, a harder coating will result in less adhesion. Examples of the change of adhesive properties as a function of the viscoelastic properties in the field of photo-crosslinkable coatings are given in the publication of the Procedures of the Third Congress of Nurnberg, European Coatings Exhibition, Document Number 3, March 1995. The main drawback of the systems described in the literature is that it is not possible to simultaneously increase two properties such as flexibility and hardness. In addition, the adhesion of the system usually decreases when the hardness of the material increases. The present invention overcomes the limitations and inconveniences of the prior art and makes it possible to increase the hardness of materials such as coatings or products or compounds for molding, by the addition of specific cross-linked microparticles, while at the same time preserving, or possibly improving, the level of flexibility of the material and at the same time improving the adhesion of the material to a substrate and more particularly towards difficult substrates, such as polyolefins and more particularly, copolymers of polyethylene or polypropylene and ethylene / propylene. Another advantage of the microparticles of the invention is their excellent compatibility, thus allowing an incorporation at high levels, without problems of compatibility and without negative effect on the rheology of the related compositions or under the conditions of application, either for the compositions of the coating or for the molding compositions. More particularly, the present invention makes it possible to obtain coatings with improved hardness and flexibility and with very good adhesion to polar or non-polar substrates, and more particularly coatings as a - - thin layer of less than 100 micrometers and preferably less than 50 micrometers on substrates with difficult adhesion such as polyolefins in general and, more particularly, polyethylene and polypropylene, without a surface treatment. Specifically, this is made possible by virtue of the presence in these compositions of the novel crosslinked acrylic microparticles of essential composition and specific structure and between 10 and 300 nm in size, which can be adapted to each application. A first object of the invention relates to crosslinked microparticles of size between 10 and 300 nm obtained by the polymerization of a composition of polymerizable ethylenically unsaturated compounds, characterized in that the composition of the polymerizable compounds comprise: a first component A representing from 50 percent to 99 mole percent of the composition cited and consisting of isobornyl (meth) acrylate and / or norbonyl (meth) acrylate and / or cyclohexyl (meth) acrylate and optionally in combination with a (meth) alkyl acrylate of 2 to 8 carbon atoms and / or methacrylate Cardura E10 a second component B consisting of at least one monomer or an oligomer comprising at least - two non-ethylenic saturations that can undergo radical-mediated polymerization a third component C consisting of at least one monomer or oligomer comprising, in addition to an ethylenic unsaturation that can undergo radical-mediated polymerization, at least a second reactive function fl which is different from non-ethylenic saturation, with the possibility of at least a partial chemical modification of the initial fl functions in final f2 functions under the condition that the selected fl functions do not react with each other during the polymerization, and that the sum of the components A, B and C is equal to 100 percent. The term "(meth) acrylate" should be interpreted completely as "acrylate and / or methacrylate". The preferred size of these microparticles is from 10 to 200 nm and more particularly from 20 to 100 nm. They can be obtained generally by polymerization for radical-mediated emulsion in an aqueous medium, or by polymerization by dispersion in a non-aqueous medium of said composition of the polymerizable compounds. An emulsifier is present in the aqueous medium, and a stabilization polymer is present in the non-aqueous medium, in accordance with common techniques known to those skilled in the art and described in the literature, such as in Advances in Polymer Science ( 1998), volume 136, pages 139-234. The specificity of these microparticles is associated with their composition. Component A can consist of a monomer or a mixture of monomers selected from the (meth) acrylates of: isobornyl, norbornyl, cyclohexyl possibly in combination with an alkyl (meth) acrylate of 2 to 8 carbon atoms and / or (meth) ) Cardura E10 acrylate. The alkyl (meth) acrylate of 2 to 8 carbon atoms can represent from 0 to 30 mole percent of component A. In the case of a mixture of isobornyl (meth) acrylate, norbonyl and cyclohexyl, the (meth) ) isobornyl acrylate preferably represents at least 50 mole percent of component A. Preferred component A is isobornyl (meth) acrylate, with a preferred proportion in the composition of polymerizable compounds of between 60 mole percent and 90 percent molar. The alkyl (meth) acrylates of 2 to 8 carbon atoms are preferably selected from the (meth) acrylates of: ethyl, propyl, n-butyl, tertiary butyl and 2-ethylhexyl and / or (meth) acrylate Cardura E10 . Component B has the function as a microparticle crosslinking agent comprising at least two ethylenic non-saturations per monomeric or oligomeric constituent, these non-saturations being capable of undergoing radical-mediated polymerization. Preferably, the constituents of B are selected from the polyfunctional ethylenic non-saturating functionality multifunctional (meth) acrylate monomers and ranging from 2 to 6, substituted or unsubstituted divinylbenzenes and / or multifunctional acrylic and / or methacrylic oligomers with polyesters unsaturated functionality ranging from 2 to 50 and with an Mn of less than 2500. More particularly, the component B may consist of a monomer or an oligomer or a mixture of monomers or oligomers or a mixture of monomers and oligomers selected from : - di (meth) acrylates of ethylene glycol, of propylene glycol, of butanediol, of 2-methyl propanediol, of neopentyl glycol, of hexanediol, of zinc and / or calcium, tri (meth) acrylates of glycerol, of trimethylolpropane and / or derivatives alkoxylates, tri- or tetra (meth) acrylates of pentaerythritol and penta- or hexa (meth) acrylates of dipentaerythritol, oligomeric diols with an Mn of less than 2500, preferably polyethers, p oliesters or polyurethanes. substituted or unsubstituted divinylbenzenes - acrylated acrylic or unsaturated polyester oligomers with an Mn of less than 2500, having a number of ethylenic non-saturations per mole of 2 to 50 and preferably 2 to 20 with the proportions of component B in the composition of the polymerizable compounds varying preferably from 0.5 percent to 10 mole percent. Component C is an agent for functionalizing the microparticles of the invention. Functions fl carried by component C may be identical or different depending on whether or not component C comprises one or more monomers and / or oligomers of identical or different fl functions, with the proviso that, when the fl functions are different, they do not they react with one another during polymerization. The functions f are preferably selected from the following functions: epoxy, hydroxyl, carboxyl, carboxylic anhydride, isocyanate, silane, amine or oxazoline. The component C is preferably present in a molar content not greater than 49.5 percent relative to the composition of the polymerizable compounds A, B and C and consists of at least one monomer and / or an oligomer selected from: acid (meth) acrylic, maleic, fumaric or itaconic acid, when fl is a carboxyl-maleic anhydride or itaconic anhydride function, when fl is a function of hydroxyalkyl carboxylic anhydride (meth) acrylates containing an alkyl of 2 to 6 carbon atoms; carbon or the mono (meth) acrylates of polyether or polyether oligomers or of polyurethane diol or polycaprolactone with an Mn of less than 1,500, when fl is a function of glycidyl hydroxy (meth) acrylate, (meth) acrylates of epoxidized dicyclopentadiene derivatives or epoxidized vinylnorbornene (meth) acrylates or alkoxylated glycidyl ether (meth) acrylates or (meth) acrylates of epoxidized cyclohexene derivatives, when fl is a function of epoxy (meth) isocyanotoethyl acrylate and mono (meth) uretene acrylates derived from diisocyanates, when fl is a function of an isocyanate (meth) acrylate bearing a trialkyl- or trialkoxysilane group, when fl is a function of silane - (meth) dimethylaminoethyl acrylate or tert-butylaminoethyl (meth) acrylate when fl is a function of 2- (5- (meth) acryloylpentyl) -1,3-oxazoline amine, when fl is a function of oxazoline. More particularly, component C is present in a molar content of 5 percent to 30 percent relative to the sum of polymerizable compounds A, B and C and is selected from: (meth) -glycidyl acrylate, (meth) - hydroxyalkyl acrylates of 2 to 6 carbon atoms, (meth) acrylic acid, maleic or anhydric acid, itaconic or anhydride acid, isocyanatoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate. Functions fl carried by component C can be chemically modified at least partially to drive the presence of modified functions f2 obtained from the functions f, the f2 functions being preferably selected: (meth) acrylates, vinyls, maleates, fumarates, itaconates, allyl alcohol esters, non-saturations based on dicyclopentadiene, unsaturated fatty esters of 12 to 22 carbon atoms or amides, carboxylic acid salts or quaternary ammonium salts. The chemical modifications of the functions fl in functions f2 can be carried out according to the methods already known in the literature. For example, the functions f2: (meth) acrylates of the fl: epoxy functions, by reaction with (meth) acrylic carboxylic acid or anhydride, by reaction with glycidyl (meth) acrylate or hydroxyalkyl (meth) acrylate containing a hydroxyalkyl of 2 to 6 carbon atoms maleates or itaconates, of epoxy or hydroxyf functions by reaction with maleic anhydride or itaconic salts of the carboxylic acid, of the carboxyl functions of fl by neutralization with a base such as sodium hydroxide, hydroxyl potassium, aqueous ammonium or an amine quaternary ammonium salts, the functions of tertiary amine fl by reaction with the inorganic or organic acid esters of allyl alcohol, of anhydride functions fl by reaction with an allylic alcohol not saturation of dicyclopentadiene (DCPD) , of carboxyl functions by addition reaction of DCPD vinyl, of hydroxyl functions by reaction with a vinyl azlactone such as 2-vinyl-4,4-dimethylazlactone or a vinyl isocyanate such as isopropenyldimethylbenzyl isocyanate esters or amides of 12 to 22 unsaturated carbon atoms of carboxyl or anhydride functions by reaction of a fatty alcohol or amine of 2 to 22 carbon atoms unsaturated.

A preferred specific composition of the microparticles of the invention comprises: from 50 percent to 95 mole percent of a component consisting of isobornyl (meth) acrylate and / or norbonyl - from 0.5 percent to 10 mole percent of a component B as defined above from 0 percent to 49.5 mole percent of a C component as defined above with the additional condition that the sum of A + B + C = 100 mole percent. Among the preferred microparticles carrying the functions fl at the beginning, mention may be made of: the microparticles carrying carboxyl functions or carboxyl functions which have been partially or completely modified in functions f2 of (meth) acrylate and / or maleate and / or fumarate and / or maleimide and / or carboxylic acid salt the microparticles carrying epoxy and / or hydroxyl fl functions and / or hydroxyl functions fl which have been partially modified into f2 (meth) acrylate functions and / or maleate and / or fumarate and / or maleimide. The (meth) acrylic and / or maleate and / or fumarate functions are advantageous in compositions that undergo medium-to-radical crosslinking: either through ultraviolet light radiation or electron beam treatment, or through a thermal initiator system radical-mediated such as a system comprising a peroxide derivative, optionally in the presence of a decomposition accelerator. The epoxy and / or hydroxyl functions may participate in compositions that may undergo photochemical crosslinking in the presence of a cationic photo-initiator or by condensation. The carboxyl functions are especially advantageous in condensation reactions. The salts of the carboxylic acid or quaternary ammonium salts are advantageous in aqueous compositions due to their water-dispersible or water-soluble functions, which makes the related microparticles water-dispersible or water-soluble in a water-based application composition. . The double functionality fl / f2 such as carboxyl / (meth) acrylate or epoxy / (meth) acrylate and / or maleate and / or fumarate, allows the use of the related microparticles in double reactive systems with a double mechanism of crosslinking by function fl o f2. Consequently, the fl / f2 functions of these cross-linked acrylic microparticles can be adapted as a function of the application and the host composition.

A second object of this invention is a specific process for preparing the microparticles of the invention which has the advantage of being simpler and more practical than those already known in the prior art. This process for preparing microparticles of the invention comprises a step of radical-mediated dispersion polymerization in a nonaqueous medium which is not solvent for the polymer formed, of a composition of polymerizable compounds A, B and C as defined for the microparticles of the invention, without the need to add a stabilizing polymer for the microparticles formed, either before, during or after the polymerization, it being possible for the aforementioned process to comprise, where appropriate, an additional step of at least a partial chemical modification of the functions fl carried by the component C as defined in the invention. This method of preparation therefore avoids the inconveniences associated with the presence of a stabilization polymer: the problem of availability of the polymer for stabilization and solubility in the polymerization medium - the negative effect on the operating qualities of the microparticles in terms of of compatibility - or reactivity of reactive functions. - The specific feature of this process is associated with the specific composition of the composition of the polymerizable compounds and more particularly with the nature of the component A of the invention, as defined above. Among the specific advantages of the microparticles obtained by this specific process, mention may be made of a compatibility and, depending on the case, a reactivity which are remarkably improved without any limitation in terms of availability or of the characteristics of the stabilization polymer. In addition, its specific structure, obtained by means of the specific process used, provides the microparticles obtained with a nature of self-dispersibility and self-stabilization in a solvent medium that is identical or comparable to that for polymerization. Similarly, this process allows the production of crosslinked microparticles that are highly monidispersible in terms of size, which is important to achieve specific rheological and viscoelastic performance qualities in certain applications in the field of coating compositions, compositions or molding compounds. .

The solvent used for this process is an organic solvent or a mixture of organic solvents that are selected from alkanes of 6 to 10 carbon atoms such as hexanes, heptanes, and more particularly n-heptane, cyclohexane, octanes, nonanes and / or alkanols. from 3 to 5 carbon atoms such as isopropanol, butanol or pentanol. Mixtures of non-polar solvents such as heptane, with polar solvents such as isopropanol are preferred for adjusting the solvation power of the medium relative to the polymerizable compounds, on the one hand, and the non-solvating power of the developing medium in a precipitation medium relative to the formed polymer, on the other hand. The weight ratio between the alkane of 6 to 10 carbon atoms and the alkanol of 3 to 5 carbon atoms can vary from 0/100 to 75/25 and more particularly from 25/75 to 50/50. This remains particularly preferred when this mixture is based on n-heptane or cyclohexane, on the one hand and on isopropanol or butanol, on the other hand. The weight ratio between the sum of component A, B and C, on the one hand, and the solvent or mixture of solvents, on the other hand, can vary from 10/90 to 50/50 and preferably from 15/85 to 30/70. This relationship is one of the parameters of the process to control the size of the microparticles. When the dilution increases the more it will be - the tendency of the size of the microparticles to decrease. The polymerization by dispersion of the ethylenically unsaturated compounds is carried out through a radical route adding a radical initiator commonly used for this type of polymerization, which is appropriate for the environment. The polymerization temperature is adapted for the decomposition temperature of the selected radical initiator and the boiling temperature of the solvent medium used and can generally vary, as a function of the initiator and the solvent medium used, from 20 ° C to 150 ° C. As examples of initiators, mention may be made of: azo derivatives such as azobisisobutyronitrile (AIBN) and derivatives, peroxides and hydroperoxides or any other initiator system which is soluble in the polymerization medium and which has been known to those skilled in the art. More particularly, these initiators can be functionalized with a reactive function f3 such as hydroxyl or carboxyl, such as for example, hydroxylated or carboxylated azo derivatives. In this case, the microparticles obtained will be at least partially functionalized with the functions f3. In addition, other radical initiators can be used for a so-called "controlled" or "active" radical mediated polymerization as described in Comprehensive Polymer Science, volume 3, pages 141 to 146, of Pergamon, London, 1989. Similarly, the agents Chain transfer such as mercaptans can be combined with the initiator in order to better control the molecular masses. The polymerization time will depend on the nature and content of the initiator and the polymerization temperature. The content of the usual initiator may vary from 0.05 to 5 weight percent relative to the sum of the polymerizable components A, B and C. According to a first embodiment of this batch process, all polymerizable components A, B and C are added, with stirring, from the beginning in the reactor containing all the solvent and which is maintained at a polymerization temperature. The monomers can also be added in the form of a solution in a certain amount of the polymerization solvent. The initiation of the polymerization is carried out, with vigorous stirring, by the gradual addition of the selected radical initiator, which is soluble in the polymerization medium. After the end of the addition of the initiator, the polymerization proceeds from a time that can vary from 1 hour to 8 hours, depending on the temperature and the nature and content of the initiator, and the nature and total concentration of the polymerizable compounds .

- - The self-stabilized microparticles formed in the polymerization medium can be recovered either after the successive steps of precipitation, by adding a non-solvent such as an alcohol in a proportion ranging from 2/1 to 5/1 by weight relative to the dispersion, and after the filtration and drying, or by means of a single evaporation step of the solvent of the dispersion medium, preferably under a reduced pressure of 10 to 30 mbar. The final size of the microparticles obtained ranges from 10 to 300 nm and preferably from 10 to 200 nm and more particularly from 20 to 100 nm as a function of the dilution of the polymerizable compounds and the nature and molar ratio of component A selected. The size of the microparticles can be reduced by increasing the content of component A and / or increasing the level of dilution of the polymerizable compounds, and / or increasing the precipitation power of the polymerization medium by adjusting the nature and / or composition of the solvent of the polymerization medium. The essential advantage of this process and its different modalities is its simplicity and its flexibility in the preparation of a large variety of microparticle structures, simply varying the nature and proportions of components A, B and C without previously defined limits of the invention.

According to a second embodiment of this process, it comprises one or more successive steps of continuous and / or batch polymerization characterized respectively by an addition of the polymerizable compounds continuously, or in a single portion per related step, respectively. When the process comprises more than one batch and / or continuous polymerization step, the composition of the polymerizable compounds may be identical or different from one step to the other. In this way, it is possible to prepare very specific microparticle structures of the multi-layer type as a function of the composition of the polymerizable compounds in each step and as a chronological order of each continuous or batch step. When the composition of the polymerizable compounds comprise components C comprising functions fl, the process as described above may comprise, after the polymerization step, an additional step of chemical modification of the function fl and / or the function f2 obtained from f1. This step of chemical modification can be carried out, depending on the case, either before the recovery of the microparticles by evaporating the polymerization solvent, or after the recovery of these microparticles, in which case the chemical modification can be carried out depending of the case, and either in bulk or if the viscosity allows it at the temperature of modification, or in solution in a solvent that is different from the polymerization solvent if the latter is inappropriate, in terms of its boiling temperature or its chemical inertness . As a preferred example of a chemical modification, mention may be made of the (meth) acrylation of reactive functions such as: epoxy and hydroxyl with (meth) acrylic acid or fumaric or itaconic acid or anhydride, or carboxylic acid or anhydride with the glycidyl (meth) acrylate or hydroxyethyl (meth) acrylate. For example, the (meth) acrylation can be carried out a solution containing from about 30 percent to 60 percent of the dispersed microparticles, in the presence of esterification catalysts such as chromium (III) diisopropyl salicylate, ethyl hexanoate. of chromium (III), ethyltriphenylphosphonium bromide or tertiary amines. A variant of this process may comprise, before the polymerization step, a dispersion step, in a non-aqueous medium of organic and inorganic microparticles which are insoluble in this medium, followed by a polymerization step as described above. In this case, the organic or organic microparticles in dispersion have sizes adapted to that of - the final microparticles that are going to be obtained. The predispersed microparticles can be selected from organic or inorganic pigments or from organic or inorganic fillers or fillers or additives or microparticles prepared above of the invention as already described as being insoluble in the dispersion medium. This variant of the process allows a coating at least partial but simple and practical, or the encapsulation of the predispersed microparticles with the aim, for example, of improving their dispersibility in other dispersion media (aqueous or organic media) or improving their compatibility in container matrices for coating, molding or composite compositions. A third object of the invention relates to coating or molding compositions or compounds comprising microparticles of the invention, as defined above. These compositions are crosslinkable or non-crosslinkable, but are preferably crosslinkable: either due to the presence of the microparticles of the invention carrying reactive functions fl and / or f2 as described above or, independently of the presence of the functions fl and / or f2, that is, through reactive functions - - intrinsic in the initial composition without the microparticles or, both by the intrinsic reactive functions in the initial composition and by those of the microparticles. Among the crosslinkable compositions, it is also possible to distinguish compositions containing only, ie, up to 100 percent, or essentially, that is, between 60 percent and 90 percent, of crosslinked acrylic microparticles that carry fl and / or f2 functions which are identical or different but which react with one another to form at least one network of cross-linking constituting the matrix of either a coating or a molding products. For example, these compositions may consist solely or essentially of cross-linked acrylic microparticles carrying (meth) acrylate f2 functions which may undergo radical-mediated crosslinking either through a thermal initiation system initiated by a common radical containing a peroxide compound. and optionally a decomposition accelerator, or through irradiation with radiation such as ultraviolet in the presence of a photoinitiator or an electron beam or beam in the absence of a photoinitiator. Other examples that illustrate these compounds can be cited as - - coating or molding compositions consisting solely or essentially of crosslinked acrylic microparticles carrying co-reactive functions of epoxy and anhydride fl, respectively. Another example of these compositions in particular for coatings, is an aqueous coating composition consisting solely or essentially of cross-linked acrylic microparticles of the invention, which carry the functions fl and / or f2 or which comprise a specific structure which makes them water-soluble. or dispersible in water having Tg and characteristics of minimum film-forming temperature which makes possible their coalescence between 0 ° C and 40 ° C. These functions fl and / or f2 may, for example, be the salts of the carboxylic acid or the ammonium salts and more particularly the quaternary ammonium salts. As a specific structure, of microparticles having this water-soluble or water-dispersible nature, mention may be made of the presence of acrylated oligomers based on polyethers such as polyethylene glycol, preferably having a molecular mass of mass average number. less than 2500 and preferably less than 1500. In the case of molding coating compositions or compounds in which the cross-linked acrylic microparticles of the invention are partial components that are reactive or non-reactive in the presence of other reactive or non-reactive components of the composition, the content of these microparticles can vary from 0.5 percent to 50 percent by weight relative to the sum of the organic components in this composition. In addition to the microparticles of the invention, these compositions comprise a base component which is the organic matrix based on the coating or the molding product and the customary additives or fillers or fillers adapted or adjusted as a proposed application function and within the capacity of a person skilled in the field. As reactive or non-reactive additives, the microparticles of the invention can be used in a crosslinkable or non-crosslinkable coating or the molding compositions, in general in order to: reduce the viscosity of these compositions, allow better wetting and better application to substrates to be coated and, in addition, the compositions with a higher solids content and consequently a lower content of the volatile organic compounds to better control, by specific application, the rheology of these compositions by adjusting the structure of the microparticles to reinforce or plasticize the matrix as a function of the compatibility and Tg of the microparticles in relation to the host matrix. The microparticles as non-reactive additives can have functions that are selected from fl and f2, as defined in the above-cited invention which, while chemically inert with respect to the host composition, can greatly improve the compatibility of the microparticle with respect to the host matrix by means of favorable physicochemical interactions. In the case of microparticles used as reactive additives, their reactive functions are selected and adapted or modified to react with the reactive functions of the cross-linked host composition or with one another. For example, in the case of a composition which may undergo thermal or radical-mediated photochemical cross-linking, containing ethylenically unsaturated monomers and / or monofunctional or multifunctional oligomers, the microparticles, after the chemical modification followed by the polymerization step, preference will be of the polyunsaturated type. The polyepoxidated or polyhydroxy reactive microparticles will be adapted for epoxide coating compositions which can be photo-crosslinked cationically in - presence of cationic photoinitiators such as triarylsulfonium or diaryliodonium salts. The polyepoxidated or polycarboxylated reactive microparticles will be adapted for crosslinking the molding coating compositions based on the epoxides and the polyamines or the dicarboxylic acid anhydride or carboxylated acrylic copolymers. Similarly, the partially neutralized polycarboxylated microparticles can serve as water-dispersible or water-soluble microparticles, depending on the degree of neutralization and can be shown in coating compositions based on aqueous dispersions of reactive or non-reactive polymers. This water-dispersible or water-soluble nature can also be imparted by a C and / or B component having constituents that are selected, respectively, from the mono- and di-acrylates or methacrylates of polyether diols such as polyethylene glycol with a less than 1500. In particular, water-dispersible or water-soluble microparticles which carry acrylate or methacrylate functions after partial modification of their initial functions fl can be used in photo-crosslinkable coatings based on aqueous dispersions of polymers of Preference acrylic polymers. The microparticles used as reactive additives have an activation function of reactivity and genuine cross-linking for the related system, due to their high functionality. The effect on the mechanical performance qualities of the coating or the molded product is reflected by increased reinforcement and flexibility, as a function of the functionality, compatibility and Tg of the microparticle chemically grafted into the host matrix, with the microparticle behaving as a filling micromaterial. or grafted or ungrafted load and / or a filling micromaterial or flexible hard load. The cohesion energy of the final material, the coating or the molding product is increased in this way with a possible positive effect on both hardness and flexibility. In addition to the hardness / flexibility compromise, the presence of the microparticles of the invention allows better adhesion of the compositions related to various polar or non-polar substrates. These substrates may be substrates capable of being coated with the coating compositions or impregnable as fillers or fillers or reinforcing agents in the molding compositions or composites. As examples of polar substrates wherein the compositions containing the microparticles of the invention provide good adhesion, mention may be made of: glass, steel, aluminum, silicon, polycarbonate, wood, glass fibers, carbon fibers, polyester or polyamide fibers and cellulose fibers. As examples of non-polar substrates which are reputed to be difficult in terms of adhesion, and which provide good adhesion performance qualities with the coating compositions and preferably with the coating compositions which may undergo radical-mediated crosslinking, mention may be made of of: polyolefins, and more particularly polyethylene and polypropylene with or without a special surface treatment, and coatings with a low surface tension, such as photo-crosslinked varnishes. Among the preferred coating compositions which have a good compromise in terms of hardness / flexibility / adhesion for polar and non-polar substrates, mention may be made of a composition that can undergo radical-mediated cross-linking containing from 0.5 percent to 50 percent by weight, preferably from 5 percent to 30 percent by weight, of crosslinked acrylic microparticles of the invention as defined above, reactive functions f2 of (meth) acrylate and / or maleate and / or maleimide and said coating composition comprises - - also mono- or multifunctional acrylic or vinyl monomers and / or mono- or multifunctional acrylic oligomers or unsaturated polyester oligomers. The mono- or multi-functional acrylic monomers that can be used are acrylic monomers of non-saturation (meth) acrylic functionality per molecule ranging from 1 to 6. More specifically, they can be selected from the following monomers and a mixture of the same: isobornyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, tridecyl (meth) acrylate, ethoxylated nonylphenol (meth) acrylate, ethoxylated or propoxylated neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate or polypropylene glycol, hexanediol (meth) acrylate, ethoxylated and / or propoxylated tri (meth) acrylate, trimethylolpropane. When oligomers such as unsaturated polyesters are present in the composition, aromatic vinyl monomers such as styrene or vinyltoluene or allyl phthalate can be used. Among the mono- or multifunctional acrylic oligomers which may be present in these compositions, and preferably with acrylic monomers, mention may be made of: (meth) acrylate oligomers of functionality ranging from 1 to 50, which are selected from: polyethers of (meth) acrylate, (meth) acrylate polyepoxides, (meth) acrylate polyesters, polyurethanes of (meth) acrylate, (meth) acrylate polycaprolactones or acrylic copolymers of at least one ester (meth) acrylic with glycidyl (meth) acrylate, the copolymers of which are then (meth) acrylated at least partially in a separate step. The number average molecular mass of these oligomers or copolymers remains less than 20,000. In a specific case of a composition, the crosslinked acrylic microparticles carrying the (meth) acrylate f2 functions can completely replace the multifunctional monomer or the oligomer of functionality > 2 as the crosslinking agent, with performance qualities remarkably improved in terms of hardness / flexibility and adhesion to the substrate. These compositions may undergo radical-mediated cross-linking: either through a pathway mediated by thermal radical in the presence of a radical-mediated thermal initiator system comprising a peroxide derivative, such as a common organic peroxide or hydroperoxide, optionally in the presence of a decomposition accelerator such as a tertiary amine or cobalt salts such as octoate of - cobalt in proportions commonly used by a person skilled in the art, and in general with a content of the peroxide derivative of between 0.5 percent and 6 percent and a content of the decomposition accelerator between 0.01 percent and 2 percent in relation to to the sum of the monomeric and / or oligomeric components, it being possible that the crosslinking can also be carried out at low temperature depending on the presence or absence of a decomposition accelerator for the peroxide derivative or via a radiation path, either by ultraviolet light in the presence of a photo-initiator system commonly used in photo-crosslinkable acrylic systems such as aromatic ketones such as benzophenone, α-hydroxy ketones, α-dicarbonyl derivatives, acyl phosphine oxides in the presence or absence of tertiary amines in proportions that vary from 0.5 percent to 10 percent relative to the sum of the monomers and / or oligomers in the composition, or by a beam or electron beam in the absence of a photo-initiator. More particularly, the preferred composition is molding that can undergo mediated crosslinking - by radical, which is intended to be applied or which is applied in the form of a coating to polar or non-polar substrates as defined above and comprising: from 0.5 percent to 50 percent and preferably from 5 percent one hundred to 30 weight percent of microparticles as defined in one of claims 1 to 7, which carry f2 functions of (meth) acrylate and / or maleate, and / or fumarate, and / or maleimide and / or vinyl. - from 50 percent to 95 percent of at least one monomer selected from isobornyl (meth) acrylate, and / or isodecyl (meth) acrylate, 2- (2-ethoxyethoxy) ethyl (meth) acrylate, (meth) tridecyl acrylate, lauryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate and 2-phenoxyethyl (meth) acrylate. from 0 percent to 5 percent by weight of alkylene diol di (meth) acrylate of 2 to 6 carbon atoms, the percentages being selected such that the total sum of the microparticles and monomers is equal to 100 percent. Even more preferably, this composition can undergo radiation crosslinking, either by ultraviolet light or by a beam or beam - of electrons The preferred thickness of the coatings that may undergo radical-mediated crosslinking is less than 100 microns and more particularly less than 50 microns. A specific case of a coating composition that can undergo radical-mediated cross-linking is a composition of an aqueous dispersion of cross-linkable polymer, comprising water-dispersible or water-soluble reactive microparticles that participate in the cross-linking. The aqueous dispersion of the crosslinkable polymer may be an acrylic emulsion which already contains a water-soluble or water-dispersible crosslinking agent based on water-dispersible or water-soluble acrylic multifunctional monomers, and / or the oligomers of > 2. The microparticles of the invention carry, for example, f2 functions of (meth) acrylate can partially or completely replace this water-dispersible or water-soluble multifunctional acrylic crosslinking agent. The dispersibility in water or water solubility of these microparticles is ensured, in this case, by the water soluble functions fl and / or f2 such as the carboxylic acid salts or the quaternary ammonium salts or by a specific water-soluble structure of a constituent of component C of the microparticle, which is selected, for example, from the (meth) acrylates of polyethylene glycol or of other polyether diols soluble in water or dispersible in water. A dispersion composition of the aqueous polymer may also comprise polymers consisting of reactive functions that are intrinsic to this polymer, which may participate in the crosslinking. The crosslinking of these aqueous polymer dispersion compositions, which contains the microparticles of the invention, is achieved, after applying a film and film formation of this composition on a substrate, either by means of a radical-mediated thermal pathway or by ultraviolet radiation. or a beam or electron beam. Another preferred coating composition of the invention is a crosslinkable composition comprising epoxidized derivatives and microparticles of the invention, which is crosslinkable either by ultraviolet light radiation in the presence of a cationic photo-initiator by condensation reaction with at least one second reactive component that is selected from: polyamines and / or polymers or copolymers functionalized by carboxy or functionalized by carboxylic anhydride. The epoxidized derivatives are selected from epoxidized or rresinic monomers, oligomers or copolymers of a functionality ranging from 1 to 50. More particularly in the case of compositions which may undergo photochemical cross-linking in the presence of a cationic photo-initiator, the monomers or preferably epoxidized oligomers are cycloaliphatic in structure. Among the cycloaliphatic epoxidized derivatives can be mentioned: epoxidized cyclohexene, 3 'carboxylate, 4'-epoxycyclohexanecarboxylate of 3,4-epoxycyclohexylmethyl, the cycloaliphatic epoxides described in WO 98/28286 or WO 98/45349. When the compositions can undergo cationic photochemical crosslinking, the microparticles of the invention are preferably selected from microparticles that carry epoxy and / or hydroxyl fl functions. The composition that can be crosslinked by condensation preferably comprises icroparticles carrying epoxy, and / or hydroxyl, and / or carboxyl, and / or anhydride, and / or isocyanate, and / or amine functions. The coating compositions of the invention are also applied to compositions comprising at least one reactive resin which is selected from unsaturated alkyds or polyesters or saturated polyesters or polyamides or polyurethanes or polyureas with microparticles of the invention, preferably comprising functions fl and / or f2 that are reactive with at least one function carried by this or this reactive resin (s). Functions fl and / or f2 therefore allow the best anchoring of the microparticles in the organic matrix with a better reinforcing and / or flexibilizing effect in the organic matrix. For example, in the case of alkyd resins, the functions fl and / or f2 can be scriptive functions such as non-saturations based on dicyclopentadiene or on allyl esters or on unsaturated fatty esters or amides. In the case of unsaturated polyesters, the f2 functions can be (meth) acrylates and preferably maleates or fumarates. Functions such as anhydride or isocyanate can be visualized, being co-reactive with the OH-end functions carried by the unsaturated polyester. The carboxyl functions fl can be visualized, for example, for maturation of the unsaturated polyesters with magnesium hydroxide, in accordance with a maturation process with magnesium hydroxide which is well known to those skilled in the art. Similar functions can be visualized and adapted by experts in the field in the case of saturated polyesters, polyamides or polyurethanes or polyureas. These coating compositions may comprise, in addition to the components - reagents, other common additives or filler or filler materials adapted to the specific need of each final application. The invention also relates to molding or composite compositions which may be molding compositions comprising filler or filler materials and / or reinforcing agents. These molding or composite compositions may comprise at least one reactive resin which is selected from unsaturated polyesters, dicyclopentadiene resins, vinyl esters, epoxides and polyamines of polyurethanes and polyureas or polyurethane-ureas or esters of cyanate or bismaleimides, with microparticles of the invention which preferably comprise the functions fl and / or f2 which are reactive with at least one function carried by this or this reactive resin (s). The molding compositions contain the microparticles of the invention may comprise inorganic and / or organic fillers or fillers, and / or reinforcing agents that are selected from: glass fibers, glass mats, carbon fibers, cellulose fibers, polyamide fibers or polyamide. A specific advantage of the microparticles of the invention that allow a reduction in the viscosity of the coating or molding compositions, and - consequently a significant reduction in the reactive and non-reactive diluents, thus fulfilling more effectively with the environmental limitations. Therefore, due to their presence, these microparticles allow simultaneously: compliance with a low content of volatile organic compounds (VOC), the incorporation of higher contents of fillers or fillers or additives, and the improvement of mechanical properties of the molding coating materials or related compounds. More particularly, the presence of these microparticles of adapted functionality for each application allows a good compromise in terms of hardness / flexibility and adhesion to various substrates and more particularly to difficult substrates. The field of application of these compositions is wide and comprises: protective varnishes, paints, adhesives, inks, coating powders, molding powders, molded articles and composites. The examples that will be given below illustrate the objects of the invention without limitation.

Examples General experimental conditions Substrates - The photo-crosslinkable formulations are deposited on the following substrates aluminum panel Q (dimensions of the panel: 0.6 x 76 x 152 cubic millimeters supplied by the company LABOMAT ESSOR), defatted with ethyl acetate glass (cleaned with acetone) polycarbonate (plate LEXAN of the company SCERT PLASTIQUE, thickness of 2 millimeters) - polypropylene (reference PP301460 supplied by the company GOODFELLOW, thickness of 0.5 mm) low density polyethylene (reference ET11452 supplied by GOODFELLOW company, thickness of 0.05 mm) Polycarbonate, polyethylene and polypropylene are preliminarily prepared with ethanol before applying the coating. For the need of certain characterizations (for example adhesion measurement), the polyolefin substrates (polyethylene and polypropylene) are treated by the Corona process before depositing the formulation (according to the conditions described in Int. Pol. Sci. Technol., Number 8, 1996, page 630). Photo-crosslinkable coating formulations In the examples presented below, coatings are obtained by mediated polymerization - by radical of a photo-crosslinkable formulation under a medium pressure ultraviolet lamp of the FUSION type (electric power or power: 120 W / cm) after 6 passages at 4.6 meters per minute. These conditions ensure the maximum conversion of acrylate double bonds in all cases. Characterization Measurement of the viscosity of the formulations The viscosity of the photo-crosslinkable formulations is a very important parameter to use light-cured films and to obtain coatings of low thickness. In the text that will be given below, the viscosities of the formulations are measured using a CARRI-MED CSL 100 stress-controlled cone / plate viscometer (CSL RHEOMETER) at 20 ° C, during a shear rate scan. Measurement of the hardness of the photo-polymerized films The hardness is measured by means of instrumented microindentation (machine FISCHERSCOPE H100) at 23 ° C. The indentation apparatus is a Vickers type pyramid with a crest angle of 136 °. The hardness values presented below correspond to the "universal" hardness values calculated according to the expression: Hμ kd2 where P is the maximum load imposed, d is the depth of indentation and k is a constant that depends on the geometry of the indenter. The load P is determined in such a way that: i) the depth of indentation is less than 1/5 of the total thickness of the film, ii) the measured hardness is essentially constant with the indented thickness. The films are analyzed systematically 24 hours after the polymerization and stored at 23 ° C and 50% relative humidity. Measurement of the flexibility of the coatings The flexibility of the systems in a substrate is calculated by means of the "T-bend" test. The test consists of rolling the coated substrate by itself and determining the number of turns after which the coating placed on the bend is no longer damaged. The successive turns are represented by 0 T, 0.5 T, 1 T, etc. (See test description in Lowe C, Rad. Cur volume 183, Number 4337, page 464). In all cases, the thickness of the films is less than 50 μm and more generally about 20 μm.

- - The substrate used is an aluminum of panel type Q described above. The curvature test T is carried out using a manual press. The detection of damage is carried out on its own by observation using binocular amplification crystals (amplification x 12). The good flexibility usually corresponds to a value of less than or equal to 2 T. The films are analyzed systematically 24 hours after crosslinking and stored at 23 ° C and 50% relative humidity. Measurement of the mechanical properties of the free film to large deformations The mechanical properties of free films to large deformations are measured in uniaxial traction at constant speed (1 millimeter / minute) and at room temperature. The crosslinked films are cut in the form of a dumbbell, using a hollow punch. The test pieces obtained in this way are marked with two reflector granules separated by 20 millimeters in order to follow the elongation during deformation using an external extensometer. The effective dimensions of the sample are typically 20 x 4 x 0.1 cubic millimeters. Measurement of adhesive properties - The adhesion of the systems is calculated by means of a cross-sectional test (ISO 2409 standard) on the aforementioned substrates. A quality that varies from 0 to 5 qualifies the behavior of the cross-cut film when it is peeled off by a known resistance adhesive (the "O" value indicates that the film remained completely on the substrate; "5" indicates that the film peeled off totally) . In our case, the detachment strength of the adhesive used (origin: TESA) for the cross-sectional test is 240 + 5 cN / centimeter (which is measured at 180 ° on a stainless steel plate). The thickness of the coatings is approximately 20 μm. The films are analyzed systematically 24 hours after the polymerization and stored at 23 ° C and 50% relative humidity. Measurement of abrasion resistance Abrasion resistance is measured by the TABER test in accordance with NFT 30-015 (5150 ABRASER machine from TABER INDUSTRY). The test consists of measuring the loss of mass retained by two abrasive wheels after 100 rotations. The films are analyzed systematically 24 hours after the polymerization and stored at 23 ° C and 50% relative humidity.

- Measurement of chemical resistance The resistance of the coatings to a chemical attack is evaluated by the "rub test" which consists of measuring the time before the total deterioration of the film when a continuous circular motion is applied to the surface of this film using a cloth soaked with the solvent. In cases treated below, the solvent is ethylethyl ketone (MEK). The films were prepared on glass plates. The thickness of the coating remains constant and is between 40 and 50 μm in all cases.

Example 1 Synthesis of crosslinked polymer microparticles (CPMs) 131.3 grams of n-heptane and 131.5 grams of 2-propanol were introduced into a reactor of 500 milliliter capacity equipped with a condenser and a mechanical stirrer, and under a gentle flow of nitrogen. The temperature rose to 70 ° C. A mixture of (meth) acrylic monomers is then charged into the reactor, the composition of which is given below: isobornyl acrylate: 69.80 grams, ie 76 mole percent (relative to the monomers) hexanediol diacrylate: 5.02 grams, that is, 5 mole percent (relative to the monomers) glycidyl methacrylate: 11.96 grams, ie 19 mole percent (relative to the monomers). The temperature is stabilized at 70 ° C and 0.78 gram of azobisisobutyronitrile (ie, 10 millimoles per liter relative to the monomers) is introduced into the reactor. The reaction is carried out under isothermal conditions (70 ° C) for 5 hours, without any significant exothermicity being observed. The dispersion remains transparent and homogeneous, at low viscosity, throughout the duration of the synthesis. At the end of the 5 hours of reaction, the conversion of the monomers is greater than 95 percent according to the monitoring of the monomers by steric exclusion chromatography and measuring the solids content in the solution. The formed CPMs were isolated by distilling the synthesis solvents: the condenser is replaced with a distillation column, 87.5 grams of toluene are added and the temperature is gradually raised to 105 ° C. The CPMs are then acrylated by reaction with an acrylic acid, at 100 ° C, in the presence of a reaction catalyst, 0.8 percent by mass of chromium (III) diisopropyl salicylate, and 0.3 percent by mass of hydroquinone to avoid any polymerization mediated - - by the radical of the acrylic functions. The chemical modification advances up to 50 percent solids, in solution in toluene, in a 250 milliliter reactor equipped with a condenser and a mechanical agitator, under a gentle flow of nitrogen. The acrylic acid is introduced in slight excess in relation to the epoxide groups in such a way that the ratio of the concentrations of the functions is: [acid] / [epoxy] = 1.05. At the end of the chemical modification, the CPMs are isolated by drying under vacuum (20 mbar) at room temperature. The final conversion of the epoxide groups is 95 percent, which corresponds to a concentration of reactive acrylic double bonds [C = C] = 9.1 x 10 ~ 4 mol / gram. The dried CPMs are in the form of a solid, which can be ground to a fine powder. The size and mass of the CPMs is determined by a multi-angle laser light scattering technique (reference: DAWN from WYATT TECHNOLOGY, operating at 632 nm), when leaving the spherical exclusion chromatography columns. The molar mass and the size of the CPMs are: μ > X 105 g / mol and Rz = 31 nm - The temperature at the beginning of the glass transition zone, gonset, for these CPMs, which is measured by differential colorimetric analysis, is 62 ° C.

Example 2 A photo-crosslinkable reference formulation (Fl) consisting, on the basis of 100 parts (by weight), of: - 47.5 parts of isobornyl acrylate (SR 506, CRAY VALLEY) 47.5 parts of an acrylated oligomer, reference PRO 971 of SARTOMER 3 parts of Darocur 1173 (CIBA GEIGY) - 2 parts of Irgacure 184 (CIBA GEIGY) was prepared at room temperature. The acrylated oligomer PRO 971 is a copolymer obtained through a radical-mediated path corresponding to the product sold in dilution, reference CN 818, by the company SARTOMER and composed of: butyl acrylate methyl methacrylate glycidyl methacrylate.

The glycidyl function of the oligomer is modified in the second step by reaction with the acrylic acid to provide the acrylated oligomer. In order to evaluate the provision of CPM with respect to the compromise in terms of hardness / flexibility / adhesive and the final film, the photo-crosslinkable formulation presented below (F2) was of course prepared: in the base of 100 parts by weight: - 47.5 parts of isobornyl acrylate (SR 506, CRAY VALLEY) 19 parts of acrylated CPM of Example 1 28.5 parts of PRO 971 (SARTOMER) 3 parts of Darocur 1173 (CIBA GEIGY) - 2 parts of Irgacure 184 (CIBA GEIGY) The two formulations have a viscosity very similar to 20 ° C. The results in Table 1 show that formulation F2 has a shear thinning nature. The properties of the corresponding films are summarized in Table II. The thicknesses of the coatings for the hardness measurement are approximately 80 to 100 μm.

- Table I - Values of the viscosities of the formulations at 50 and 250 s_1, measured at 20 ° C Formulation Viscosity regime shear stress (Pa.s) (s-1) 50 2 Fl 250 2 50 1.77 F2 250 1.64 Table II Summary of the physical properties of the films obtained using Fl and F2 Hardness Flexibility Resistance Strength (N / mm2) "T-bend" to chemical cross section (s) in glass (adhesion) Fl 42 1. 5 T 5 80 + 10 F2 76 1. 5 T 1 80 + 10 Example 3 The CPMs of Example 1 are introduced into a mixture of acrylic monomers (mixture A) is presented below: - - isobornyl acrylate (SR 506): 60 percent by mass isodecyl acrylate (SR 395, from CRAY VALLEY); 38 percent by mass hexanediol diacrylate (SR 238): 2 percent by mass Photo-crosslinkable formulations are prepared based on mixture A and contain different mass concentrations of CMP. The compositions are summarized in Table III.

Table III - Compositions of the different formulations used in Example 3 (based on 100 parts) Formulations Mixture A CPM Darocur Irgacure 1173 184 F3 (ref) 95 0 3 2 F4 90.25 4.75 3 2 F5 87.9 7.1 3 2 F6 85.5 9.5 3 2 F7 80.75 14.75 3 2 F8 76 19 3 2 F9 66.6 28.5 3 2 FIO 57 38 3 2 - Table IV - Viscosity of the formulations at 20 ° C Formulations Viscosity regime shear stress (Pa.s) (s-1) 50 0.04 F6 250 0.03 50 0.18 F8 250 0.14 50 0.65 F9 250 0.50 50 2.78 FIO 250 2.16 The physicochemical properties (hardness, flexibility, chemical resistance) of the different coatings are given in the summary table V. The thicknesses of the films for the measurement of hardness are from 20 to 25 μm.

- Table V - Physicochemical properties of coatings Formulations Hardness Flexibility Resistance (N / mm2) "T curvature" chemical F3 (a) 0 T 20 + 10 F8 »5 1 T 55 + 10 F9 52 1 T 65 + 10 FIO 80 1.5 T 60 + 10 (a) not measurable (value too low) Table VI shows the results of the abrasion tests, compared to the values obtained with a coating that is taken as a comparison example that has good resistance to abrasion. The abrasion properties are measured in films of 80 to 100 μm.

- Table VI - Abrasion properties of coatings Formulations Resistance to the rest of the abrasion hardness values (mg) (N / mm2) F3 16. 3 - (a) F9 36 52 FI O 40. 8 80 Reference (b) 30 14 (a): not measurable (too low value) (b): composition, per 100 p, of formulation 20 p CN976 (from CRAY VALLEY) 52 p CN550 (from CRAY VALLEY) 23 p CN501 (from CRAY VALLEY) 3 P Darocur 1173 2 p Irgacure 184 Table VII shows the adhesion measurements on different substrates.

Table VII - Adhesion properties of coatings FormulaAluVidrio Poli- PoliPoliTreatment Treatments minio s carboethylene propicon with clones nato leno crown crown (PC) (PE) (PP) PE PP F3 0 0 0 5 5 5 5 F4 0 0 0 5 5 5 5 F5 0 0 0 5 0 0 0 F6 0 0 0 0 0 0 0 F7 0 0 0 0 0 0 0 F8 0 0 0 5 0 0 0 F9 0 0 5 5 5 0 0 FIO 0 0 5 5 5 5 5 These examples perfectly illustrate a simultaneous increase in adhesion and hardness properties in the case of coatings containing CPMs of the invention.

Example 4 The prepared formulation contains: - 46. 55 parts (by weight) of isobornyl acrylate (SR 506) - 19.95 parts of 2- (2-ethoxyethoxy) ethyl acrylate (SR 256 of CRAY VALLEY) - 28.5 parts of CPM of Example 1 3 parts of Darocur 1173 2 parts of Irgacure 184 The mechanical properties measured at 23 ° C in the free film are: Young's modulus = 130 MPa Elongation at break = 70 percent Break stress = 12.5 MPa These results illustrate a good compromise for this coating in terms of hardness / flexibility with good adhesion of the coating to glass and aluminum. The reference film without CPM is extremely brittle with virtually no elongation at break, thus not allowing it to be characterized according to the methods described above.

Claims (10)

1. CLAIMS 1. The crosslinked microparticles between 10 and 300 nm in size, obtained by polymerization of a composition of the polymerizable ethylenically unsaturated compounds, characterized in that the composition of the polymerizable compounds comprises: a first component A representing 50 to 99 mole percent of the composition and consists of isobornyl (meth) acrylate and / or norbonyl (meth) acrylate and / or cyclohexyl (meth) acrylate, and / or (meth) acrylate of Cardura E10, and optionally in combination with an alkyl (meth) acrylate from 2 to 8 carbon atoms - a second component B consisting of at least one monomer or an oligomer comprising at least two ethylenic non-saturations that can undergo radical-mediated polymerization, the monomer or the oligomer being other than a (meth) allylic acrylate - a third component C consisting of at least one monomer or an oligomer comprising, in addition to an ethylenic unsaturation which can be For radical-mediated polymerization, at least a second reactive function of fl that is different from non-ethylenic saturation, with the possibility of at least a partial chemical modification of the initial functions fl in the final functions f2 under the condition that the selected fl functions do not react with each other during polymerization, with the sum of components A, B and C being 100 percent.
2. 2. The microparticles according to claim 1, characterized in that they carry functions fl carried by component C, which are selected from: epoxy, hydroxyl, carboxyl, carboxylic anhydride, isocyanate, silane, amine, oxazoline, and, where appropriate, the functions fl are at least partially modified in functions f2 which are selected from: (meth) acrylates, vinyls, maleates, maleimides, itaconates, allyl alcohol esters, non-saturations based on dicyclopentadiene, unsaturated fatty esters of 12 to 22 atoms of carbon or amides, carboxylic acid salts or quaternary ammonium salts. The microparticles according to either of claims 1 and 2, characterized in that the component C is present in a molar content of not more than 49.5 mole percent relative to the sum of the polymerizable compounds, and is selected from: ( met) glycidyl acrylate, hydroxyalkyl (meth) acrylate - from 2 to 6 carbon atoms, (meth) acrylic acid, maleic acid or anhydride or fumaric acid, itaconic acid or anhydride, isocyanatoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 2- (5-methacryloylpentyl) -1 , 3-oxazoline. The microparticles according to one of claims 1 to 3, characterized in that the component B is selected from the multifunctional (meth) acrylate monomers of a functionality ranging from 2 to 6, substituted or unsubstituted divinylbenzenes and / or oligomers of multifunctional (meth) acrylics or unsaturated polyesters of functionality ranging from 2 to 50 and with an Mn of less than 2500. 5. The microparticles according to one of claims 1 to 4, characterized in that the composition of the polymerizable compounds comprises: - from 50 percent to 95 percent of a component A consisting of isobornyl (meth) acrylate and / or norbonyl (meth) acrylate and / or butyl (meth) acrylate from 0.5 percent to 10 percent of a component B consisting of at least one monomer and / or an oligomer selected from: di (meth) acrylates of: ethylene glycol, propylene glycol, butanediol, 2-methyl propanediol, neopentyl glycol, hexanediol, olig diol numbers with an Mn of less than 2500, preferably polyethers, polyesters or polyurethanes, divinylbenzenes substituted or unsubstituted, unsaturated polyester oligomers or acrylic oligomers acrylated with an Mn of less than 2500 and having a number of ethylenic non-saturations per mole from 2 to 50 not more than 49.5 mole percent of a component C consisting of at least one monomer and / or an oligomer selected from: - (meth) acrylic acid, maleic, fumaric or itaconic acid, when fl is a function of carboxyl maleic anhydride or itaconic anhydride when, fl is a function of hydroxyalkyl carboxylic anhydride (meth) acrylates containing an alkyl of 2 to 6 carbon atoms or mono (meth) ) polyether- or polyester- or polyurethane diol acrylates or the polycaprolactone oligomers with and Mn of less than 1500, when fl is a function of glycidyl hydroxy (meth) acrylate, (meth) acrylates of epoxidized derivatives of dicyclopentadiene or (meth) epoxidized vinyl norbornene acrylates or - - alkoxylated glycidyl ether (meth) acrylates or (meth) acrylates of epoxidized cyclohexene derivatives, when fl is a function of isocyanatoethyl epoxy (meth) acrylate and a urethane mono (meth) acrylates derived from diisocyanates, when fl is a function of isocyanate (meth) acrylates bearing a trialkyl or trialkoxysilane group, when fl is a function of dimethylaminoethyl silane (meth) acrylate or tert-butylaminoethyl (meth) acrylate, when fl is a function of amine 2- (5) - (meth) acryloyl pentyl) -1, 3-oxazoline, when fl is an oxazoline function with the sum of A + B + C being equal to 100 percent. 6. The microparticles according to one of claims 1 to 5, characterized in that they carry functions fl or hydroxyl functions fl which are partially or totally modified in functions of (meth) acrylate and / or vinyl and / or maleate, and / or fumarate and / or maleimide, and / or carboxylic acid salt f2. The microparticles according to one of claims 1 to 6, characterized in that they carry epoxy, and / or hydroxyl functions or functions of - - epoxy and / or hydroxyl which are partially modified in terms of (meth) acrylate f2. 8. The process for preparing microparticles according to claims 1 to 7, characterized in that it comprises a step of radical-mediated dispersion polymerization in a nonaqueous medium that is a non-solvent for the polymer formed, of a composition of polymerizable compounds as is defined in one of claims 1 to 5, without any addition of the stabilizing polymer for the microparticles formed, either before, during or after the polymerization being possible that the process comprises, where appropriate, an additional step of chemical modification at least partial of the functions fl carried by component C as defined in one of claims 1 to 3 and 5. 9. The coating or compound molding composition, characterized in that it comprises microparticles as defined in one of claims 1 7. The composition according to claim 9, characterized in that it is crosslinkable consists solely or essentially of microparticles as defined in one of claims 1 to 7 which comprises functions fl and / or f2 which are identical or different and which can be crosslinked between the microparticles, forming at least one network of crosslinking. 4 - . 4 - one hundred to 50 weight percent of microparticles as defined in one of claims 1 to 7. The composition according to one of claims 9 to 11, characterized in that the composition is a coating composition. The composition according to claim 12, characterized in that the coating composition is a composition that can undergo radical mediated crosslinking comprising mono- or multifunctional acrylic or vinyl monomers, and / or multifunctional acrylic oligomers and microparticles defined in accordance with one of claims 1 to 7, which carry (meth) acrylate and / or maleate and / or fumarate, and / or maleimide functions f2 obtained from at least a partial modification of the starting functions f1. The composition according to claim 12 or 13, characterized in that the coating composition is a composition that can undergo cross-linking by radiation. 15. The composition according to claim 13 or 14, characterized in that the crosslinkable composition comprises, as acrylic monomers, isobornyl (meth) acrylate and / or isodecyl (meth) acrylate, lauryl (meth) acrylate, (met) 2- (2-ethoxyethoxy) ethyl acrylate, tridecyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, and / or as acrylic oligomers, at least one acrylic oligomer selected from : polyether (meth) acrylates, polyester (meth) acrylates, polyurethane (meth) acrylates, polycaprolactone (meth) acrylates, epoxy (meth) acrylates and (meth) acrylic acrylic copolymers. The coating composition according to one of claims 12 to 14, characterized in that it is intended to be applied or applied in the form of a coating on polar or non-polar substrates and comprising: - 0.5 to 50 percent by weight percent and preferably from 5 percent to 30 percent by weight of microparticles as defined in one of claims 1 to 7 carrying f2 functions of (meth) acrylate, and / or maleate, and / or fumarate, and / or maleimide of 50 percent to 99.5 percent by weight of at least one monomer selected from isobornyl (meth) acrylate and / or isodecyl (meth) acrylate or lauryl (meth) acrylate tridecyl acrylate - from 0 percent to 5 percent by weight of di (meth) acrylate of alkylene-diol of 2 to 6 carbon atoms - the percentages being selected in such a way that the total sum of the microparticles and monomers is equal to 100 percent. 17. The coating composition according to claim 16, characterized in that: the polar substrates are: glass, steel, aluminum, silicon, polycarbonate, wood, glass fibers, carbon fibers, cellulose fibers, polyester or polyamide fibers - non-polar substrates are: polyolefins and more particularly polyethylene, polypropylene and ethylene / propylene copolymers with or without special surface treatment, and low surface tension coatings. 18. The coating composition according to claim 16 or 17, characterized in that it is applied to the substrate in the form of a thin film with a thickness of less than 100 microns, preferably less than 50 microns. The composition according to claim 12, characterized in that the coating composition is an aqueous dispersion composition of a crosslinkable polymer, comprising water-dispersible or water-soluble reactive microparticles participating in the cross-linking. 20. The coating composition according to one of claims 9 to 12, characterized in that the composition is a composition comprising epoxidized derivatives. 21. The coating composition according to claim 20, characterized in that it can undergo cross-linking by ultraviolet radiation in the presence of a cationic photo-initiator and comprising microparticles carrying epoxy and / or hydroxyl fl functions. 22. The coating composition according to claim 20, characterized in that it can undergo crosslinking by condensation reaction with at least one second reactive component selected from: polyamines and / or polymers or copolymers functionalized with carboxy or functionalized with carboxylic anhydride . 23. The coating composition according to claims 20 and 22, characterized in that when the composition can be crosslinked by condensation reaction it comprises microparticles carrying f and / or f2 functions of epoxy, and / or hydroxyl and / or carboxyl and / or of anhydride. 24. The coating composition according to one of claims 9 to 12, - - characterized in that this composition comprises at least one reactive resin which is selected from: alkyd or unsaturated polyesters or saturated polyesters or polyamides or polyurethanes or polyureas and microparticles as defined in one of claims 1 to 7, which preferably comprise functions fl and / or f2 which are reactive with therefore a function carried by this or this reactive resin (s). The molding composition according to claims 9 to 11, characterized in that it comprises at least one reactive resin which is selected from: unsaturated polyesters, dicyclopentadiene resins, vinyl esters, epoxides and polyamines or polyurethanes and polyureas or polyurethane -amides and microparticles as defined in one of claims 1 to 7, preferably comprising the functions fl and / or f2 which are reactive with at least one function carried by this or this reactive resin (s). 26. The molding composition according to claim 125 characterized in that it comprises inorganic and / or organic fillers or fillers and / or reinforcing agents that are selected from: glass fibers, glass mats, carbon fibers, fiber cellulose, polyester fibers or polyamide.