Abstract: The present invention relates to precipitated calcium carbonate particles being at least partially in the form of nanofibers or nanochain like agglomerates, wherein the particles are at least partially coated with at least one coating agent, use of such precipitated calcium carbonate particles and a process for the manufacture of such precipitated calcium carbonate particles.

Abstract: A method of preparing a transparent polymer material includes mixing mineral nanoparticles selected from nanoparticles of alkaline-earth metal carbonates, alkaline-earth metal sulfates, metallic oxides, oxides of metalloids, and siloxanes, and a composition A including at least one thermoplastic polymer in the molten state selected from polycarbonate (PC), polystyrene (PS) and polymethyl methacrylate (PMMA) in order to obtain a master-batch, the mixture of step i) including at least 25% and at most 75% by weight of the mineral nanoparticles. The master-batch obtained in step i) is mixed with a composition B of a thermoplastic polycarbonate matrix (PCm) in the molten state, to obtain a transparent polymer material including at most 10% by weight of the mineral nanoparticles, preferably at most 5% by weight of the mineral nanoparticles.

Abstract: A method of preparing a transparent polymer material includes i) obtaining composite nanoparticles having mineral nanoparticles at least partially coated with at least one monomer and/or at least one polymer suitable for promoting physicochemical interactions at the interface between the mineral nanoparticles and a thermoplastic polycarbonate matrix, the mineral nanoparticles being surface-modified by the monomer and/or the polymer, either directly by grafting or directly by adsorption of the monomer and/or polymer onto the surface of the mineral nanoparticles; or via a coupling agent selected from a chlorosilane or an organosilane including a functional group that is capable of reacting by a radical pathway. The composite nanoparticles obtained in step i) are mixed with the thermoplastic polycarbonate matrix in the molten state to obtain the transparent polymer material.

Abstract: Alkaline earth metal carbonate exhibiting a resistance to acids expressed as pH of less than 7 measured after suspending 1.0 g of the particles in a mixture made of 20 ml of toluene and 80 ml of an aqueous phase consisting of deionized water, 11.76 g/L of citric acid monohydrate, 2.57 g/L of NaCl and 0.068 mol/L of NaOH, after 35 minutes of stirring at 25° C. and at 1 000 rpm, or expressed as a moisture pick-up lower than or equal to 2 g water/kg of calcium carbonate after one week of storage at 22° C. and 50% relative humidity, or as a Differential Scanning Calorimetry (DSC) spectrum showing at least one peak between 170 and 190° C. when measured at a heating rate of 10° C./min under nitrogen atmosphere from 25 to 250° C. in open cells. Process for the preparation of said particles, compositions containing said particles and the use thereof.

Abstract: The present invention provides a method of preparing a transparent polymer material, the method comprising steps i) and ii) in any order, the steps consisting in: i) mixing: mineral nanoparticles having a form factor strictly greater than 1.0; and a polymer matrix comprising a quantity of at least 80% by weight of a polycarbonate (PC) first thermoplastic polymer and of a second transparent thermoplastic polymer other than the first thermoplastic polymer, in order to obtain a mixture; and ii) heating the polymer matrix to the molten state, on its own or in the mixture; to obtain the transparent, polymer material, the mixture of step i) comprising a quantity of mineral nanoparticles having a form factor strictly greater than 1.0 that is strictly less than 5% by weight.

Abstract: The present invention provides a method of preparing a transparent polymer material, the method comprising steps i) and ii) in any order, the steps consisting in: i) mixing: mineral nanoparticles having a form factor strictly greater than 1.0; and a polymer matrix comprising a quantity of at least 80% by weight of a polycarbonate (PC) first thermoplastic polymer and of a second transparent thermoplastic polymer other than the first thermoplastic polymer, in order to obtain a mixture; and ii) heating the polymer matrix to the molten state, on its own or in the mixture; to obtain the transparent, polymer material, the mixture of step i) comprising a quantity of mineral nanoparticles having a form factor strictly greater than 1.0 that is strictly less than 5% by weight.

Abstract: Tablet comprising at least one biologically active substance and an excipient, in which the excipient contains calcium carbonate and at least one additive selected from fatty acids, their salts, their esters, lipid materials, polysaccharides, polyvinylpyrrolidone and polyvinylpyrrolidone derivatives, acrylic compounds, mono-, di- or triglyceride esters, animal proteins, and mixtures of at least two of these. Method for producing these tablets. Use of calcium carbonate in tablets containing at least one biologically active substance, for the prolonged release of this substance.

Abstract: A method of preparing a transparent polymer material includes mixing mineral nanoparticles selected from nanoparticles of alkaline-earth metal carbonates, alkaline-earth metal sulfates, metallic oxides, oxides of metalloids, and siloxanes, and a composition A including at least one thermoplastic polymer in the molten state selected from polycarbonate (PC), polystyrene (PS) and polymethyl methacrylate (PMMA) in order to obtain a master-batch, the mixture of step i) including at least 25% and at most 75% by weight of the mineral nanoparticles. The master-batch obtained in step i) is mixed with a composition B of a thermoplastic polycarbonate matrix (PCm) in the molten state, to obtain a transparent polymer material including at most 10% by weight of the mineral nanoparticles, preferably at most 5% by weight of the mineral nanoparticles.

Abstract: A method of preparing a transparent polymer material includes i) obtaining composite nanoparticles having mineral nanoparticles at least partially coated with at least one monomer and/or at least one polymer suitable for promoting physicochemical interactions at the interface between the mineral nanoparticles and a thermoplastic polycarbonate matrix, the mineral nanoparticles being surface-modified by the monomer and/or the polymer, either directly by grafting or directly by adsorption of the monomer and/or polymer onto the surface of the mineral nanoparticles; or via a coupling agent selected from a chlorosilane or an organosilane including a functional group that is capable of reacting by a radical pathway. The composite nanoparticles obtained in step i) are mixed with the thermoplastic polycarbonate matrix in the molten state to obtain the transparent polymer material.

Abstract: The present invention relates to particles of an alkaline earth metal carbonate which are at least partially coated with at least one coating agent and which have a specific surface of more than 50 m2g?1 before coating. Preferably, the alkaline earth metal is calcium and the coating agent comprises a compound selected from the group consisting of organic sulfonic acids, alkylsulfates, fatty acids and the salts thereof.

Abstract: Process for the production of precipitated calcium carbonate particles, structured at the nanoscale, by carbonation of milk of lime in the presence of a crystallization controller selected from the following list: polyaspartic acid, dioctyl sodium sulphosuccinate, polyacrylic acid, the molecular weight of which is between 500 and 15 000, and citric acid. When the crystallization controller is citric acid, its concentration in the milk of lime is between 5 and 15%.

Abstract: Alkaline earth metal carbonate exhibiting a resistance to acids expressed as pH of less than 7 measured after suspending 1.0 g of the particles in a mixture made of 20 ml of toluene and 80 ml of an aqueous phase consisting of deionized water, 11.76 g/L of citric acid monohydrate, 2.57 g/L of NaCl and 0.068 mol/L of NaOH, after 35 minutes of stirring at 25° C. and at 1 000 rpm, or expressed as a moisture pick-up lower than or equal to 2 g water/kg of calcium carbonate after one week of storage at 22° C. and 50% relative humidity, or as a Differential Scanning Calorimetry (DSC) spectrum showing at least one peak between 170 and 190° C. when measured at a heating rate of 10° C./min under nitrogen atmosphere from 25 to 250° C. in open cells. Process for the preparation of said particles, compositions containing said particles and the use thereof.

Abstract: The present invention relates to particles of an alkaline earth metal carbonate which are at least partially coated with at least one coating agent and which have a specific surface of more than 50 m2g?1 before coating. Preferably, the alkaline earth metal is calcium and the coating agent comprises a compound selected from the group consisting of organic sulfonic acids, alkylsulfates, fatty acids and the salts thereof.

Abstract: Process for the production of precipitated calcium carbonate particles, structured at the nanoscale, by carbonation of milk of lime in the presence of a crystallization controller selected from the following list: polyaspartic acid, dioctyl sodium sulphosuccinate, polyacrylic acid, the molecular weight of which is between 500 and 15 000, and citric acid. When the crystallization controller is citric acid, its concentration in the milk of lime is between 5 and 15%.

Abstract: Process for the production of precipitated calcium carbonate particles, structured at the nanoscale, by carbonation of milk of lime in the presence of a crystallization controller selected from the following list: polyaspartic acid, dioctyl sodium sulphosuccinate, polyacrylic acid, the molecular weight of which is between 500 and 15 000, and citric acid. When the crystallization controller is citric acid, its concentration in the milk of lime is between 5 and 15%.

Abstract: Process for making a solid compound by precipitation, using a high intensity mixing reactor and comprising the steps of (A) introducing a first fluid material containing a first reactant and a second fluid material containing a second reactant into said reactor, in order to obtain a mixed fluid, in order to cause the first reactant to react with the second reactant to form a solid compound by precipitation in the mixed fluid; (B) withdrawing the mixed fluid containing the precipitated solid obtained in step (A) from the reactor, and; (C) optionally separating the precipitated solid compound from at least one fraction of the mixed fluid.

Abstract: Tablet comprising at least one biologically active substance and an excipient, in which the excipient contains calcium carbonate and at least one additive selected from fatty acids, their salts, their esters, lipid materials, polysaccharides, polyvinylpyrrolidone and polyvinylpyrrolidone derivatives, acrylic compounds, mono-, di- or triglyceride esters, animal proteins, and mixtures of at least two of these. Method for producing these tablets. Use of calcium carbonate in tablets containing at least one biologically active substance, for the prolonged release of this substance.

Abstract: Composition containing (a) a synthetic resin and (b) a filler, the filler containing (b1) at least one inorganic substance having a specific surface area higher than or equal to 15 m2/g and (b2) at least one surface-active agent and/or one coating agent. Method for producing the composition. Use of the composition for the production of films, and films obtained starting with this composition.

Abstract: Process for the production of precipitated calcium carbonate particles, structured at the nanoscale, by carbonation of milk of lime in the presence of a crystallization controller selected from the following list: polyaspartic acid, dioctyl sodium sulphosuccinate, polyacrylic acid, the molecular weight of which is between 500 and 15 000, and citric acid. When the crystallization controller is citric acid, its concentration in the milk of lime is between 5 and 15%.