PARTICULAR FUNCTIONALIZED RETICULATING AGENT

Abstract

FUNCTIONALIZED PARTICULAR CROSSING AGENT The present invention relates to hybrid particles (1), formed of inorganic particles functionalized by at least one molecule (2) bearing at least one ionic function involved in at least one ion pair and / or at least one electrostatic function involved in at least one electronegative group capable of engaging in at least one hydrogen bond, said at least one molecule (2) being an organosilane, and at least one counterion and / or at least one hydrogen bond donor / acceptor (3) bearing at least one C=C double bond, the quantity of ion pairs and / or electronegative groups capable of engaging in hydrogen bonding on the surface of the inorganic particles being between 0.5 and 20 mol% relative to the quantity of precursors of the inorganic particles. (Figure to be published with the abstract: Figure 1)

Description

Title of the invention: FUNCTIONALIZED PARTICULAR CROSSING AGENT technical field

[0001] The invention lies in the field of the synthesis and functionalization of particles as a crosslinking agent for the formation of reversible / dynamic crosslinking networks in polymers. Previous technique

[0002] Several molecular crosslinking agents are used to crosslink thermoplastic and elastomeric polymers after the synthesis phase. In the case of polyethylenes, they are industrially crosslinked with peroxides or silanes. These form the PER-a family for crosslinking with peroxides and the PER-b family for crosslinking with silanes. Crosslinking must not occur during the forming stage, such as extrusion, to avoid damaging the equipment. Therefore, the type of peroxide and the forming parameters must be carefully selected, as is the case for PER-a and PER-b. Furthermore, since this type of crosslinking is not reversible, the polymers lose their ability to be reshaped and are therefore no longer recyclable.For example, PER can only be reused after being ground up to produce fillers for other plastics, which limits their usability.

[0003] Another type of polymer, called a vitrimer, emerged in the 2010s, involving cross-linking of macromolecular chains by reversible organic covalent bonds. These bonds are dynamic, as they are involved in chemical exchange or breaking / reforming reactions, triggered by an external stimulus such as a temperature increase or light or radical irradiation. The dynamic nature of these bonds allows the vitrimer to be theoretically recyclable, while having mechanical properties close to those of thermosets.

[0004] There are two main strategies for preparing this type of polymer. The first is based on the copolymerization of complementary, multifunctional monomers bearing the functions involved in the exchange reactions. The second consists of the post-functionalization of existing polymer matrices in one or more steps. The molecules thus engaged in these reversible reactions can be considered crosslinking agents. The selected crosslinking agents can release volatile molecules during the crosslinking step, leading to defects in the final material. In the case where dynamic bonds are involved in transesterification reactions, a catalyst is necessary to activate the exchanges. This can lead to premature aging of the polymer matrix and reduced performance after reshaping. For dynamic bonds between dioxaborolane groups, the crosslinking agents are boronic esters. Their production is not yet optimized, resulting in high production costs. Furthermore, there is often a large polarity difference between nonpolar polymers and reversible crosslinking points, leading to phase segregation that is not yet controlled and whose impact is not yet understood.

[0005] Crosslinking agents enabling these exchange reactions may be incompatible with certain polymer families due to their low reactivity and nonpolar nature, as is the case for polyolefins. Those that have shown conclusive results are involved in siloxane bond exchange reactions, exchange reactions between amine and vinylogurethane, between boronic esters, between sulfur functional groups, or in transesterification reactions. Patents have been filed for these last three types of dynamic bonds.

[0006] Ionomers are another family of polymers based on ionic crosslinking. These are thermoplastic copolymers in which one of the repeating units bears ionic or ionizable groups, with crosslinking achieved by the introduction of divalent metal cations. Resins marketed under the name Surlyn® are an example. These are copolymers of ethylene and methacrylic acid. The ionic repeating units are carboxylate groups partially neutralized by metal salts, generally zinc (Zn2+). The metal salts involved in this type of crosslinking can then be considered crosslinking agents. The advantage of ionic crosslinking lies in the reversibility of the ionic bonds when heated.The insertion of the crosslinking agents, namely metallic salts, requires complex devices where the humidity level must be controlled. Furthermore, it has been shown that ionic groups cluster within the matrix and form nanodomains. The morphology of these nanodomains, and by extension that of the ionomers, is complex, not yet well understood, and remains uncontrolled.

[0007] Various types of inorganic particles have been used in nanocomposites, such as metals (Al, Fe, Au, and Ag), metal oxides (ZnO, Al₂O₃, CaCO₃, and TiO₂), and metalloids (SiO₂). It is common to functionalize these particles with organic groups to stabilize them and improve their dispersion within the polymer matrix. Indeed, the properties imparted to the polymer are enhanced when the compatibility of the fillers with the polymer matrix and their dispersion state are increased. For oxides, functionalization is generally carried out using organosilane in solution. The advantage of this technique is the wide variety functional groups can be grafted onto the particles. In this way, particles have been given the properties of crosslinking agents, but in an irreversible manner.

[0008] Instead of metallic salts, an ionomer with negatively charged particles as crosslinking agents was described in US patent 11,370,896 B2. The described nanocomposite consists of silica nanoparticles functionalized with a sulfonate-type anionic group, which dynamically binds / crosslinks to a PU / PLA copolymer bearing pendant imidazolium cationic groups. This material is used in film form and has demonstrated thermo-stimulated shape memory and repair capabilities, as well as an increase in its elongation at break and Young's modulus. The nanoparticles used are commercially available and are subsequently functionalized with an organosilane bearing a sulfonate group. This functionalization is carried out in an acidified aqueous solution and requires a mixing time of 24 hours followed by dialysis of the solution for 3 days.

[0009] For any crosslinking agent in particulate form, its functionalization with organosilanes is carried out primarily in an aqueous medium, using a batch process, which limits productivity and generates a significant amount of solvated waste. However, all these particles induce covalent crosslinking of the polymer matrices, leading to the same problems mentioned previously, namely a loss of the reshaping and recyclability properties of the hybridized polymer matrices.

[0010] The published patent document WO 2017 / 207913 Al discloses dynamic crosslinking agents that can impart new properties to polymer matrices. However, these crosslinking agents are molecular and not particulate. Description of the invention

[0011] The present invention aims to overcome at least one of the drawbacks of the aforementioned prior art.

[0012] More particularly, the invention aims to provide hybrid particles, formed of inorganic particles functionalized by at least one molecule bearing at least one ionic function involved in at least one ion pair and / or at least one electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond, said at least one molecule being an organosilane, and at least one counterion and / or at least one hydrogen bond donor / acceptor bearing at least one C=C double bond, the quantity of ion pairs and / or electronegative groups capable of being involved in at least one hydrogen bond on the surface of the inorganic particles being between 0.5 and 20% mol relative to the quantity of precursors of inorganic particles.

[0013] By “hybrid particle” is meant a particle consisting of an inorganic core and a surface comprising organic molecules.

[0014] The particles according to the invention have the following advantages.

[0015] The hybrid particles of the invention, acting as reversible crosslinking agents or crosslinking agents, are compatible with thermoplastics and / or elastomers that can be crosslinked or functionalized using peroxide. Indeed, unlike ionomers or vitrimers, which involve copolymerization with a monomer bearing a specific function for reversible crosslinking, hybrid particles have the advantage of being usable independently of the polymer to be crosslinked. They allow for the universal and reversible crosslinking of thermoplastic and / or elastomer polymers, thereby promoting their recyclability and thus increasing the repairability index of the parts concerned, improving their mechanical properties, thermal resistance, operating temperature, and therefore their thermal stability.

[0016] The incorporation of these crosslinking agents into a thermoplastic polymer and / or an elastomer makes it possible to obtain a hybrid material with increased dimensional stability at high temperatures and thus higher mechanical properties at high temperatures. At low temperatures, the mechanical properties, such as the Young's modulus of the thermoplastic polymer or elastomer, are only slightly impacted, i.e., for example, this impact is less than or equal to 20%, which is an advantage compared to the insertion of other types of crosslinking agents that more significantly degrade the mechanical properties.

[0017] By "low temperature" we mean here a temperature above ambient temperature and which can go up to the melting of semi-crystalline thermoplastics or up to the glass transition temperature of amorphous thermoplastics.

[0018] Furthermore, the crosslinking agents described in the present invention are particles of sufficient size to avoid all HSE (Health, Safety, and Environment) problems associated with the handling of nanoparticles. They are synthesized and functionalized in a single step, without producing waste, unlike other particulate crosslinking agents functionalized with organosilane or boronic esters used in certain vitrimers.

[0019] Ion pairs, by definition, contain a stoichiometric quantity of anions and cations. Said anions are preferably sulfonates, carboxylates (such as maleates, fumarates, itaconates, and fatty acids), acetates, bromates, and chlorates. Said cations are preferably ammoniums, pyridiniums, imidazoliums, hydroniums, and guanadiniums.

[0020] The molecule, bearing at least one ionic function involved in at least one ion pair and / or at least one electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond, is an organosilane. By way of example, the organosilane is very preferably a molecule of the formula Si(OR)3X, with R being preferably chosen from among the methoxy, ethoxy, propoxy, butoxy groups, and X being a group bearing an anion, preferably of the sulfonate, carboxylate type, such as maleates, fumarates, itaconates and fatty acids, acetates, bromates, and chlorates, or a cation, preferably of the ammonium, pyridinium, imidazolium, hydronium, and guanadinium types.

[0021] Alternatively, organosilane is a molecule of formula Si(OR)2X2, with R preferably being selected from the methoxy, ethoxy, propoxy, butoxy groups, and X being a group bearing an anion, preferably of the sulfonate, carboxylate type, such as maleates, fumarates, itaconates and fatty acids, acetates, bromates, and chlorates, or a cation, preferably of the ammonium, pyridinium, imidazolium, hydronium, and guanadinium type.

[0022] According to another alternative, organosilane is a molecule of formula Si(OR)X3, with R being preferably chosen from the methoxy, ethoxy, propoxy, butoxy groups, and X being a group bearing an anion, preferably of the sulfonate, carboxylate type, such as maleates, fumarates, itaconates and fatty acids, acetates, bromates, and chlorates, or a cation, preferably of the ammonium, pyridinium, imidazolium, hydronium, and guanadinium type.

[0023] According to one embodiment, said molecule carries only a single ionic function involved in at least one pair of ions.

[0024] According to another embodiment, said molecule carries only a single electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond.

[0025] According to another embodiment, said molecule carries an ionic function and an electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond.

[0026] According to another embodiment, said molecule carries at least two ionic functions.

[0027] According to another embodiment, said molecule carries at least two electrostatic functions involved in at least two electronegative groups capable of being involved in at least two hydrogen bonds.

[0028] According to another embodiment, said molecule carries at least two ionic functions and one electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond.

[0029] According to another embodiment, said molecule carries an ionic function and at least two electrostatic functions involved in at least two electronegative groups capable of being involved in at least two hydrogen bonds.

[0030] According to another embodiment, said molecule carries at least two ionic functions and at least two electrostatic functions involved in at least two electronegative groups capable of being involved in at least two hydrogen bonds.

[0031] By way of examples of organosilane, the most preferred are dimethyloctadecyl(3-trimethoxysilyl)propyl ammonium chloride, trimethyl(3-trimethoxysilyl)propyl ammonium chloride, n,n-didecyl-n-methyl-n-(3-trimethoxysilyl)propyl ammonium chloride, 4-(trimethoxysilylethyl)benzyltrimethyl chloride, 3-aminopropyltriethoxysilane, 4-aminobutyltriethoxysilane, 2-(2-pyridylethyl)trim ethoxysilane, 2-(4-pyridylethyl)triethoxysilane, 3-(trihydroxysilyl)-l-propanesulfonic acid, 3-(guanidinyl)propyltrimethoxysilane, the disodium salt of carboxyethylsilanetriol, 3-(trihydroxysilyl)-l-propanesulfonic acid and 3-(trihydroxysilyl)propyl methylphosphonate sodium salt.

[0032] The counterion and / or hydrogen bond donor / acceptor carries at least one C=C double bond advantageously involved in the polymer crosslinking reaction by radical grafting carried out using a peroxide-type compound. In this way, the polymer and the particles are connected by one or more ionic and / or electrostatic bonds. The C=C double bond may originate from an alkene, such as (meth)acrylate, styrenic, and vinyl groups.

[0033] The counterion and / or hydrogen bond donor / acceptor may be selected from the group consisting of a compound bearing a sulfonate group, such as potassium 3-sulfopropyl methacrylate or sodium 4-vinylbenzenesulfonate, a compound bearing an ammonium group, such as catecholammonium corynein, (3-carboxypropyl)trimethylammonium chloride, or N,N,N-trimethyl-3-[(2-methyl-l-oxo-2-propen-l-yl)oxy]-l-propanaminium, a compound bearing a carboxylate group, such as maleic acid, methacrylic acid, or acrylic acid, a compound bearing an amine group, such as ethyl 2-(dimethylamino)methacrylate, 3-buten-l-amine, N-vinylformamide, or 4-vinylaniline, and a group bearing a pyridine group, such as 2-vinylpyridine.

[0034] For the sake of clarity in the specific context of the invention, it should be specified that a hydrogen bond is an electrostatic interaction between two polar groups which occurs when a hydrogen atom (H) covalently bonded to a strongly electronegative atom such as nitrogen (N) or oxygen (O) is subjected to the electrostatic field of another strongly electronegative atom located nearby.

[0035] The number of ion pairs and / or electronegative groups that can be involved in at least one ionic and / or hydrogen bond on the surface of the inorganic particles is adjusted to obtain optimal properties according to the chemical nature of the ionic functions. The quantity of ion pairs on the surface is between 0.5 and 20 mol% relative to the quantity of inorganic particle precursors, and preferably between 1 and 10 mol%.

[0036] The particles used before functionalization, called inorganic particles, preferably have a sphericity coefficient greater than or equal to 0.75, preferably greater than or equal to 0.9. The inorganic particles are very preferentially spherical.

[0037] In the context of this invention, it is understood that the sphericity coefficient of a particle represents the ratio of the particle's smallest diameter to its largest diameter. For a perfect sphere, this ratio is equal to 1.

[0038] Said inorganic particles are preferably individualized.

[0039] By "individualized" we mean a set of particles in which the particles are not aggregated, that is to say that each particle in the set is not linked to other particles by strong chemical bonds, such as covalent bonds.

[0040] Preferably, the inorganic particles are individualized and / or spherical.

[0041] The inorganic particles are preferably made up of a three-dimensional silica (SiO2) network, the diameter of which is between 0.1 and 100 µm.

[0042] The inorganic particles preferably have a diameter between 0.3 and 40 µm, and even more preferably between 1 and 10 µm.

[0043] The precursors of the inorganic particles are metallo-organic precursors, preferably silica precursors. The precursors of the inorganic silica particles are, for example, silicon chlorides, such as silicon tetrachloride, or silicon alkoxides such as tetraethoxysilane, tetramethoxysilane, or tetra-n-propoxysilane.

[0044] Said inorganic particles are synthesized by inorganic polymerization of precursors, in particular silica, following hydrolysis and condensation reactions, carried out by aerosol.

[0045] Surprisingly, this aerosol process allows the synthesis and functionalization of hybrid particles in a concomitant manner.

[0046] Thermoplastic polymers and / or elastomers compatible with said hybrid particles may be chosen from the group consisting of polyolefins, preferably chosen from polyethylene, polypropylene, rubber, ethylene / vinyl acetate copolymers EVA, thermoplastic elastomers of the POE type such as poly(ethylene-octene) PEC8 or poly(ethene-butene) PEC4, EPDM elastomers, thermoplastic styrenic block elastomers such as SBS (polystyrene-b-polybutadiene-b-polystyrene), SIS (polystyrene-b-polyisoprene-b-polystyrene) or SEBS (polystyrene-b-poly(ethylene-butylene)-b-polystyrene), NBR (nitrile-butadiene rubber) elastomers, SBR (styrene-butadiene rubber) elastomers or SIR (styrene-isoprene rubber) elastomers, or mixtures thereof.

[0047] The invention also relates to a method for manufacturing hybrid particles according to the invention, by aerosol, comprising the following steps: a. Nebulization, in a reactor, of a first hydroalcoholic or aqueous solution containing one or more precursors of inorganic particles, preferably silica, with a mass concentration between 0.1 and 20%, and of a second alcoholic or hydroalcoholic solution comprising at least one molecule bearing at least one ionic function involved in at least one ion pair and / or at least one electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond, said at least one molecule being an organosilane, and at least one counterion and / or at least one hydrogen bond donor / acceptor bearing at least one C=C double bond, the quantity of ion pairs and / or electronegative groups capable of being involved in at least one hydrogen bond being calculated with respect to the molar quantity of said precursors of inorganic particles varying between 0.5 and 20%mol,to obtain a mist of droplets from the first and second solutions; b. Heating said fog to a temperature between 50°C and 100°C for a predetermined duration for the formation of inorganic particles and evaporation of the solvent; c. Heating of said particles obtained during step b) to a temperature called condensation for the transformation of said precursors into the inorganic part of said hybrid particles. d. Recovery of said hybrid particles.

[0048] The predetermined duration of step b) is preferably less than or equal to 10 s, and even more preferably less than or equal to 5 s.

[0049] By "condensing temperature" is meant a temperature between 50 and 250 °C, preferably between 100 and 200 °C, and even more preferably about 150 °C.

[0050] The process of the invention is a continuous process requiring a limited number of preparation steps. It allows for the simple production of non-aggregated, functionalized hybrid particles in a single step, without the production of waste, with by-products that can be recycled and / or reused. This process makes it easy to vary the surface state of the hybrid particles by changing the chemical nature and quantity of the molecules present. Thus, unlike molecular crosslinking agents, the hybrid particles of the present invention can be adapted to vary the dynamics of bond exchange while also providing several other properties due to the nature of the compounds used (UV protection, magnetism, coloration, etc.).

[0051] Inorganic particles are synthesized and functionalized in a single step and by aerosol to form hybrid particles according to the invention. This synthesis process involves a first step of atomizing solutions into droplets which are heated to be transformed into individual solid particles.

[0052] According to one embodiment, the first solution is an aqueous or hydroalcoholic solution, with a pH between 2 and 4. Preferably, the first solution is an aqueous solution.

[0053] The second solution is advantageously an aqueous, pure alcoholic or hydroalcoholic solution, this second solution being able to be methanol, ethanol or propanol when it contains an alcohol, without being limited to these examples of alcohol.

[0054] According to one embodiment, in the case of use of silica, the silica precursors are silicon chlorides, such as silicon tetrachloride, or silicon alkoxides, such as tetraethoxysilane, tetramethoxysilane, or tetra-n-propoxysilane.

[0055] According to one embodiment, the precursors of inorganic (non-functionalized) particles are those mentioned above.

[0056] The quantity of ion pairs and / or electronegative groups that can be involved in at least one hydrogen bond of step a) is preferably between 0.5 and 10%mol, and even more preferably between 0.8% and 3%mol relative to the quantity of inorganic particle precursors.

[0057] The other compounds or groups, such as ion pairs, the counter-ion, molecules, organosilanes, etc.; involved in the process are as defined above.

[0058] According to an alternative embodiment to step a), the first and second solutions form a single solution of inorganic precursors and ion pairs and / or electronegative groups capable of being involved in at least one hydrogen bond. This single solution contains, in this case, just enough alcohol to allow the dissolution of the ion pairs and / or electronegative groups capable of being involved in at least one hydrogen bond.

[0059] According to one embodiment, in the case of the two distinct solutions (first and second solutions), they are nebulized at the same time and they meet at the outlet of a nebulizing nozzle of an atomizing device. In this case, the solution containing the inorganic precursor is nebulized into the center of the solution containing the molecule bearing at least the ion pair and / or at least the electronegative group capable of being involved in at least one hydrogen bond.

[0060] The process can advantageously be implemented by means of a commercially available aerosol atomization device, such as a Büchi-B290 reactor or atomizer. Such an atomizer comprises the following main elements: a solution(s) aspiration device via a peristaltic pump, a compressed gas inlet, a heating module, an atomization nozzle, a drying cylinder and a recovery container.

[0061] The atomizing nozzle may be of various conventional arrangements, of the double, triple or more nozzle type, for the synthesis of hybrid particles formed from inorganic particles having a coefficient of sphericity greater than or equal to 0.75 and / or an average diameter between 0.1 and 100 sqm.

[0062] According to one embodiment, the process may advantageously include a stirring step for a duration of 10 min to 48 h, before the nebulization of step a) in order to hydrolyze the precursors of inorganic particles with three-dimensional network.

[0063] Preferably, the stirring step time is between 10 and 24h for a solution at pH 2, or between 30 min and 2h for a solution at pH 3.

[0064] The process may include, before the nebulization step a) and after the stirring step, a conventional step of drawing the solution(s) defined above towards an atomization nozzle of an atomizer by means of a compressed gas heated by a heating module.

[0065] Said aspiration step is typically carried out by a peristaltic pump, a syringe pump or any other element fulfilling this function.

[0066] According to an embodiment A, the inorganic particles are functionalized, by aerosol co-condensation of organosilanes and silica precursors, with an organosilane bearing a quaternary ammonium group. The quaternary ammonium group may be linked to a carbon chain, this carbon chain being from 1 to 18 carbons, preferably from 10 to 18 carbons. The counterion in this case is a sulfonate, a carboxylate, an acetate, a bromate, or a chlorate carried by a molecule that also has a C=C double bond, such as potassium 3-sulfopropylmethacrylate or sodium 4-vinylbenzenesulfonate in the case of a sulfonate. This double bond may originate from an alkene such as styrene, (meth)acrylate, or vinyl groups. Alternatively, the organosilane can carry a sulfonate function and the counter-ion can be a quaternary ammonium linked by a C=C double bond.Preferably, the organosilane is ammonium chloride. of dimethyloctadecyl (3-trimethoxysilyl)propyl bearing a quaternary ammonium and a long carbon chain, and the counter-ion is potassium 3-sulfopropyl methacrylate, bearing a sulfonate anion and a methacrylate function:

[0067] [Chem.l] f OCHs

[0068] Similarly, the ion pair can be made between N,N,N-trimethyl-3-[(2-methyl-l-oxo-2-propen-l-yl)oxy]-l-propanaminium and 3-(trihydroxysilyl)-l-propanesulfonic acid:

[0069] [Chem.2]

[0070] According to another embodiment B, the inorganic particles can be functionalized with an organosilane bearing a primary amine group in its acidic form (NH3+) and whose counterion bears a carboxylate group and a C=C double bond, for example, maleic acid in its maleate form. Similarly, the ionic groups can be reversed. It is possible to have an organosilane bearing a carboxylate group and its counterion being an amine also bearing a C=C double bond. Preferably, the organosilane is 3-aminopropyltrieth oxysilane and the counterion is maleic acid.

[0071] [Chem.3] OCH3 H H3CO-Si''^^Nx OCH3 HH OCH3 SHOCH3 OCH3

[0072] According to an embodiment C, the surface of the inorganic particles may include one or more hydrogen bonds. In these cases, the organosilane, covalently bonded to the particle, bears a pyridine functional group. The nitrogen of the pyridine group is then involved in a hydrogen bond with the hydrogen of a carboxyl group. The carboxyl group is borne by a molecule that also has a C=C double bond. The organosilane may bear the carboxyl group, and the molecule bearing the C=C double bond may also contain a pyridine. Preferably, the organosilane is 2-(2-pyridylethyl)trimethoxysilane, and the molecule bearing both the carboxylic acid and the C=C double bond is maleic acid.

[0073] [Chem.4]

[0074] The present invention also relates to a motor vehicle comprising at least one element, said element comprising a material incorporating hybrid particles according to the invention.

[0075] Advantageously, the material comprising the particles according to the present invention is used to manufacture one or more elements of a vehicle, for example a motor vehicle, a train, a boat or any other vehicle.

[0076] The vehicle is typically a motor vehicle, such as a car, a truck, a bus, etc.

[0077] According to another aspect of the invention, the hybrid particles are used as a crosslinking agent in plastic materials, without limitation, including interior or exterior plastic parts of a vehicle, for example, the dashboard, doors and decorative trim, etc.

[0078] Advantageously, the invention makes it easier to comply with European directives requiring the recovery of 95% of the components of end-of-life motor vehicles (Directive 2000 / 53 / EC).

[0079] The invention is described in more detail in the following examples with reference to the figures. Brief description of the drawings

[0080] [Fig.1] is a schematic representation of hybrid particles according to one embodiment of the invention;

[0081] [Fig.2] represents an example of an atomizing device (atomizer) according to an embodiment of the invention. Detailed description Example 1

[0082] Figure 1 represents an example of hybrid particles

[0083] These silica (SiO2) particles, hybrid 1 (illustrated on the left side of [Fig. 1]), have two molecules on their surface. The first molecule (numbered 2 in [Fig. 1]) carries a positively charged functional group. The second molecule (numbered 3) carries a negatively charged functional group, which forms a more or less strong ionic or electrostatic bond. This second molecule 3 also carries a C=C double bond that allows for the radical grafting (illustrated by the dashed arrow) of the particles to thermoplastic polymers and elastomers. Alternatively, the first molecule 2 can carry a negatively charged functional group and the second molecule 3 a positively charged functional group, the second molecule 3 also possessing a C=C double bond. Example 2

[0084] An example of an atomization device 4 is given in [Fig.2].

[0085] It comprises the following main elements: a solution(s) aspiration device via a peristaltic pump 6, a compressed gas inlet 8 (inlet temperature), a gas outlet 9, a heating module 10, an atomizing nozzle 12, a drying cylinder 14, a recovery container 16, a cyclone device 18, and a temperature probe 20 (outlet temperature).

[0086] A process for manufacturing hybrid particles includes steps of drawing the precursor and ion pair solution(s) by the peristaltic pump 6 to the atomization nozzle 12 via a compressed gas heated by the heating module 10 (zones E and F of [Fig. 2]). An atomization step of The solution(s) of precursor and ion pair droplets is shown in zone G, followed by a droplet drying step in the drying cylinder 14, as shown in zone H. After this drying / heating step, a hybrid particle 1 recovery step takes place (zone I), the flow out of zone H being directed to the cyclone device 18, the gases being evacuated by the gas evacuation 9 upstream of said cyclone device 18, and the hybrid particles 1 are collected.

[0087] Steps a), b) and c) of the process of the invention correspond to zones G and H of the device (nebulization-heating). Step d) corresponds to zone I (particle recovery). Example 3

[0088] In the case of embodiment A, the process is implemented as follows.

[0089] The synthesis of hybrid particles is carried out by aerosol. For this, the The ion pair is prepared by mixing stoichiometric amounts of anion and cation in methanol. A second aqueous solution, acidified to pH 2, is prepared containing tetraethoxysilane (TEOS) to achieve a silica concentration of 1 wt%. This solution is stirred for 8 hours to hydrolyze the TEOS. The ion pair is then added to this TEOS solution. Between 0.5 mol% and 20 mol% of the ion pair is added relative to the amount of TEOS. This mixture is nebulized in a Büchi-B290 atomizing reactor. This reactor is heated to 150°C at the inlet, corresponding to an outlet temperature of approximately 90°C. The flow rate of the nebulized solution is 1.5 mL / min, and the airflow for nebulization is 740 L / h. Finally, the airflow for recovering particles is set at 27 m3 / h.

[0090] In the case of embodiment B, the process is implemented as follows.

[0091] The hybrid particles are synthesized by aerosol but according to two different protocols: either by nebulizing a solution at pH=3 containing the TEOS and the ion pair, or by nebulizing two solutions, one containing the TEOS and the other the ion pair. In both cases, the ion pair is prepared by mixing anion and cation in stoichiometric quantities in methanol.

[0092] Then, in the first case, an acidified aqueous solution at pH=3 is prepared, containing tetraethoxysilane (TEOS) to achieve a silica concentration of 1% by mass. This solution is stirred for 45 minutes to hydrolyze the TEOS. The ion pair is then added to this TEOS solution. Between 1 and 10 mol% of ion pairs are added relative to the amount of TEOS. This mixture is nebulized in a Büchi-B290 atomizing reactor. This reactor is heated to 150°C at the inlet, which corresponds to an outlet temperature of approximately 90°C for an ion pair concentration below 5 mol%; otherwise, the reactor is heated to The temperature is 50°C, resulting in an outlet temperature of approximately 35°C. The nebulized solution flow rate is 1.5 mL / min, and the airflow for nebulization is 740 L / h. Finally, the airflow for particle collection is set at 27 m³ / h.

[0093] In the second case, an aqueous solution A, acidified to pH 2, is prepared containing tetraethoxysilane (TEOS) to achieve a silica concentration of 1% by mass. This solution is stirred for 8 hours to hydrolyze the TEOS. The ion pair is added to a solution B composed of 75% by volume of absolute ethanol and 25% by volume of distilled water. The amount of ion pair is calculated to correspond to a molar concentration between 1% and 6% relative to the amount of TEOS in solution A. Both solutions are nebulized in a Büchi-B290 atomizing reactor using a nozzle consisting of three nested concentric channels. Solution A is nebulized into the central channel at a flow rate of 1.5 mL / min. Solution B is nebulized into the channel surrounding the central channel at a flow rate of 0.75 mL / min. Finally, the external channel allows air circulation at a flow rate of 740 L / h. The reactor is heated to 150°C.The airflow for collecting the particles is set at 27 m3 / h.

[0094] In the case of embodiment C, the process is implemented as follows.

[0095] The hybrid particles are synthesized by aerosol, by nebulizing two solutions, one containing TEOS and the other the molecules interacting by hydrogen bonding. The parameters of this process are equivalent to the second case described previously for embodiment B. Examples 3.1-3.34

[0096] Tables 1 and 2 show the fabrication of hybrid particles using the device of Example 2 by varying the specific operating conditions.

[0097] Examples 3.1-3.25 (visible in Table 1) relate to the process implemented with a double nozzle, and Examples 3.26-3.34 (visible in Table 2) with a triple nozzle.

[0098] Table 1 in which: A. Parameters for using a dual nozzle# Process parameters

[0099] W: Atomizer inlet temperature (°C)

[0100] X: Solution flow rate (mL / min)

[0101] Y: Airflow enabling nebulization (L / h)

[0102] Z: Airflow enabling the recovery of hybrid particles (m3 / h) Solution parameters

[0103] A: Mass concentration in TEOS (%weight or %wt in English)

[0104] B: Molar quantity of PI (pair of ions and / or electronegative groups capable of being involved in at least one hydrogen bond) relative to the quantity of TEOS (% molSi)

[0105] C: pH

[0106] D: Hydrolysis time of TEOS after addition of PI (ion pairs and / or electronegative groups capable of being involved in at least one hydrogen bond)

[0107] T: Hydrolysis time after the addition of the PI (pair of ions and / or electronegative groups capable of being involved in at least one hydrogen bond)

[0108] Table 2 in which: A. Parameters for using a triple nozzle# Process parameters

[0109] W: Atomizer inlet temperature (°C)

[0110] XI: Flow rate of solution 1 (mL / min)

[0111] X2: Flow rate of solution 2 (mL / min)

[0112] Y: Airflow enabling nebulization (L / h)

[0113] Z: Airflow enabling the recovery of hybrid particles (m3 / h) Solution 1 parameters

[0114] A: Mass concentration in TEOS (%weight or %wt in English)

[0115] Cl:pH

[0116] D: Hydrolysis time of TEOS after addition of PI (pair of ions and / or electronegative groups capable of being involved in at least one hydrogen bond) Solution parameters 2

[0117] B: Molar quantity of PI (ion pair and / or electronegative groups capable of being involved in at least one hydrogen bond) relative to the quantity of TEOS (% molSi)

[0118] C2: pH

[0119] R: EtOH / H2O volume ratio (%v)

[0120] Chemical nature of the organic molecules forming the ion pair and / or the electronegative groups capable of being involved in at least one hydrogen bond

[0121] a: organosilane

[0122] [3: Counterion and / or hydrogen bond donor / acceptor bearing at least one double bond C=C

[0123] al: NC18+ = Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride

[0124] a2: NC+ = Trimethyl(3-trimethoxylilyl)propyl ammonium chloride

[0125] a3: APTES = 3-aminopropyltriethoxysilane

[0126] a4: If Pyridyne = 2-(2-pyridylethyl)trimethoxysilane

[0127] [31; SO3 = potassium 3-sulfopropylmethacrylate

[0128] [32: styrS03 = sodium 4-vinylbenzenesulfonate

[0129] [33: Maleic acid

[0130] When a double nozzle is used, the hybrid particles have a diameter ranging from approximately 1 pm to approximately 40 pm. When a triple nozzle is used, the hybrid particles have a diameter ranging from approximately 1 pm to approximately 3 pm.

[0131] In both cases, the hybrid particles have a sphericity coefficient greater than 90%, i.e. greater than 0.9.

[0132] The invention has been illustrated and described in detail in the drawings and the preceding description. This description is to be considered illustrative and given by way of example and not as limiting the invention to this single description. Numerous embodiments are possible.

[0133] [Tables 1] Parameters of hybrid particle synthesis Properties of hybrid particles Chemical nature PI Process parameters Solution parameters Particle size / average diameter Sphericity coefficient Examples s PW (T;) X | Y (mt / min) i (L / h) Z (m3 / h) A 8 l C (%molSI) | DT (microns) (%) 3.1 . _............. al aï p1 JT 150 “W 1.5 | 740 „ p740 27 1 2 | 2 8h 1h ïh 2.23 5 >90 3.3 al pi 150 4.5 | 740 27 1 2 | .2 8h 1h 19.9 >90 3.4 al “aï” pi 'pr 150 ”'Ï50 ' 6 | 740 27 1 ""'"y"""" 2 2 8h '"'8h"" 1h 39.3 ______ >90 >90 3.6 ai pi 150 1.5 î 740 27 0.8 2 | 2 8h ïh 1.5 >90 3.7 al pi 150 1.5 | 740 27 1.2 2 d 2 8h 1h 3.4 >90 3.8 al p1 150 1.5 I 740 27 3 2 | 2 8h 1h 3.2 >90 3.9 al ft 150 1.5 | 740 27 1 1 \ 2 8h 1h 2.8 >90

[0134] [Table 1] (continued) GJ nj ci 05 3.23 go] NJ^ GJ NJ 3.20 SU' CO w 3.16 3.15 w 3.13 a> NJ cl 3.10 a œ €» G CJ a! aaw R al a2 B a OSR a Œ T» NJ Cû X5 OJ "CS M XJ 15 XJ 'ta Xa> $ "2 OS 1 1 150 ost ad o] 150 091 150 150 150 09 i 150 <n Q 094 OSL <nl 150 SU b Ci □d bî b bi tn ai en tn 1.5 in 30 ai | 740 | | O^L | | on | °| | 740 | 1 740 1 Xx 0 ’-si Ê 4^ > 0 | 740 | 077 | 072 1 | 740 | 1 072 1 | 740 072 I 4N. 0 1 | LZ i \ a NJ “M •'■'U : 27 | 1 27 | 1 27 \ 1 27 | 1 1 | LZ 1 | LZ 1 | LZ 27 § 1 1 | LZ 1 I LZ 1 1 LZ 27 | 1 NJ NJ NJ J œ § -a NJ NJ NJ M NJ M NJ M nj; en ■JJ W GJ ud w NJ MN> M NJ NJ MM 1h 1h 07 4 Er MS yg CO » 3- S 24h NJ œ a' o&l 00 es- cr C 10m o> P u4 es 31 woe 30m 5 M 03 O 3 S 1h 5r| Sr O 05 05 ......24 c — — 23 —™ W bo 4*1 2.5 U 3.3 « 1.5 w 4N NJ 2.3 W' N> O OJ b V CO | >90 VRV 1 COI "l 06< | >90 V <0 OV <0 O y CD CS v © 0 06< | V © 0 >90 V ¢0 O \ >90 V <0 0

[0135] [Tableaux2] w PU CO 3.32 UJ U 3.3 M CO 3.27 ___ ÎM G> Exempt QW "CO CO en o «4 i 83 i 150 091 | gîl | «4 53 150 «4 33 ï 150 a O a 4» .^. if X» ww en en o| o a4 | p3 | 150 ; wa 3 H}} \ i° Nature Chemical Parameters i Procedure parameters \ Parameters solution 2 i \ solution 1 Pi \ Parameters of the synthesis of hybrid particles in in 1.5 in en in tn in XI (ml / min) 0.75 \ 740 p in 4a O 0^Z \ SL Q o in O p in a \ 7 5 0 7 5 . 075 ^740 0.75 | 740 (MfO \ {^ry^) K | SX 27 \ 1 27 \ 1 27 \ 1 27 \ 1 1 Zc nj 27 | 2 Z | U21 12h | 2 9h î NJ NJ BD (%müSS0 00 œ s 05 05 o>| c» OJ C2 75 / 25 001 / 0 50 / 50 "si p NJ en 75 / 2 25 / Si 75 | 75 / 25 x ni M æ O x < 06« 9' 1 06< ZZ ÔJ V «3 O 1.3 >90 en V KJ OMV CO O . , NJ.

Claims

Demands

1. Hybrid particles (1), formed of inorganic particles functionalized by at least one molecule (2) bearing at least one ionic function involved in at least one ion pair and / or at least one electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond, said at least one molecule (2) being an organosilane, and at least one counterion and / or at least one hydrogen bond donor / acceptor (3) bearing at least one C=C double bond, the amount of ion pairs and / or electronegative groups capable of being involved in at least one hydrogen bond on the surface of the inorganic particles being between 0.5 and 20 mol% relative to the amount of precursors of the inorganic particles.

2. Hybrid particles (1) according to claim 1, wherein the inorganic particles have a coefficient of sphericity greater than or equal to 0.75, preferably greater than or equal to 0.9, or are spherical.

3. Hybrid particles (1) according to claim 1 or 2, wherein the inorganic particles are made up of a three-dimensional silica (SiO2) network, the average diameter of which is between 0.1 and 100 µm, preferably between 0.3 and 40 µm, even more preferably between 1 and 10 µm.

4. Hybrid particles (1) according to any one of claims 1 to 3, wherein the inorganic particles are functionalized with an organosilane group (2) bearing a quaternary ammonium function, the counter-ion (3) being a sulfonate carried by a molecule having a C=C double bond, or with an organosilane group (2) bearing a sulfonate function, the counter-ion (3) being a quaternary ammonium linked to a C=C double bond.

5. Hybrid particles (1) according to any one of claims 1 to 3, wherein the inorganic particles are functionalized with an organosilane group (2) bearing a primary amine function in acid form (NH3+), the counter-ion (3) being a carboxylate carried by a molecule having a C=C double bond, or with an organosilane group (2) bearing a carboxylate function, the counterion (3) being an amine carried by a molecule having a C=C double bond.

6. Hybrid particles (1) according to any one of claims 1 to 3, wherein the surface of the inorganic particles comprises at least one hydrogen bond, the organosilane group (2) being covalently bonded to said inorganic particle, the organosilane group (2) bearing at least one electronegative group, preferably a pyridine function whose nitrogen is involved in a hydrogen bond with the hydrogen of a carboxylic function borne by a molecule (3) having a C=C double bond, or the organosilane group (2) bearing the carboxylic function, the molecule (3) bearing the C=C double bond comprising at least one electronegative group, preferably the pyridine function.

7. A method for manufacturing hybrid particles (1) according to any one of claims 1 to 6, by aerosol, comprising the following steps of: a. Nebulizing (G), in a reactor (4), a first hydroalcoholic or aqueous solution containing one or more precursors of inorganic particles, preferably silica, of mass concentration between 0.1 and 20%, and a second alcoholic or hydroalcoholic solution comprising at least one molecule (2) bearing at least one ionic function involved in at least one ion pair and / or at least one electrostatic function involved in at least one electronegative group capable of being involved in at least one hydrogen bond, said at least one molecule (2) being an organosilane, and at least one counterion and / or at least one hydrogen bond donor / acceptor (3) bearing at least one C=C double bond,the quantity of ion pairs and / or electronegative groups that can be involved in at least one hydrogen bond being calculated with respect to the molar quantity of said inorganic particle precursors varying between 0.5 and 20 mol%, to obtain a mist of droplets of the first and second solutions; b. Heating (H) said mist to a temperature between 50°C and 100°C for a predetermined duration for the formation of inorganic particles and the evaporation of the solvent; c. Heating (H) said particles obtained in step b) to a condensation temperature for the transformation of said precursors into the inorganic part of said hybrid particles (1). d. Recovery (I) of said hybrid particles (1).

8. A process according to claim 7, comprising a stirring step for a duration of 10 min to 48h, before nebulization (G) in step a) in order to hydrolyze the precursors of three-dimensional network inorganic particles.

9. A process according to claim 7 or 8, wherein the first and second solutions form a single solution of inorganic precursors and ion pairs and / or hydrogen bonds.

10. A method according to any one of claims 7 to 9, comprising, before the nebulization step (G) and after the stirring step, a step of drawing (E) said solution(s) into an atomization nozzle (12) of an atomizer (4) by means of a compressed gas heated (8) by a heating module (10).

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