Synthèse et utilisation de matériaux hybrides lamellaires pour l'élaboration et la caractérisation de nanocomposites polymères

L objectif de la thèse est d élaborer des matériaux hybrides organiques-inorganiques lamellaires originaux et de les disperser dans une matrice polymère afin d obtenir des nanocomposites. La mise en œuvre des nanocomposites s est faite à chaque fois dans deux types de matrices, le polyéthylène (PE) et le polyamide-12 (PA-12). Deux types d hybrides lamellaires y ont été dispersés. Le premier est l oxyde lamellaire KTiNbO5, modifié chimiquement par intercalation d alkylamines de différentes longueurs de chaîne carbonée pour améliorer sa compatibilité avec les différentes matrices polymères. La dispersion de ces matériaux hybrides a permis d améliorer plusieurs propriétés des matrices hôtes comme la stabilité thermique, la résistance mécanique et la résistance au feu. La deuxième famille de matériaux élaborés est celle des phosphonates de cuivre lamellaires porteurs de chaînes alkyles de différentes longueurs. L objectif de cette étude est de préparer un matériau hybride avec un métal de transition en vue de son incorporation dans le polymère. Une étude structurale approfondie de la série homologue a mis en évidence deux types de composés : hydratés pour les chaînes alkyles courtes (nombre de carbone =10. Ces deux types structuraux ont montré des comportements magnétiques différents. Enfin, l incorporation de ces charges dans les matrices polyéthylène et polyamide-12 a révélé que la nature covalente de la liaison chimique entre la partie organique et le feuillet inorganique ne permet pas d obtenir un état d exfoliation suffisant pour bénéficier de l effet nano sur les propriétés physiques.The aim of this work is to elaborate original lamellar hybrid materials and disperse them in a polymer matrix to obtain nanocomposites. They have been prepared using two different matrixes, one apolar (polyethylene) and one polar (polyamide-12). The two lamellar hybrid systems have been dispersed in these matrixes and studied as part of the hybrid nature. The first one, the lamellar oxide KTiNbO5, has been chemically modified with alkylamines having different carbon chain lengths in order to be compatible with the different polymer matrixes. The dispersion of such materials has allowed improving several properties like thermal stability, mechanical resistance and fire resistance. The second family studied is the copper alkylphosphonate one. They have been prepared with different alkyl chain lengths. The aim of this study is to prepare a hybrid material with a transition metal and to disperse it in the polymer matrixes. A deep structural study of the homologue series has revealed two types of compounds: hydrated for the short alkyl chains (number of carbon atoms=10. These two structural types have shown different magnetic behaviours. Finally, the incorporation of these fillers in polyethylene and polyamide-12 has revealed that the chemical nature of the bond which links the organic part to the inorganic one of the hybrid does not allow obtaining an efficient exfoliation mechanism.CAEN-BU Sciences et STAPS (141182103) / SudocSudocFranceF

Photopolymerization kinetics, photorheology and photoplasticity of thiol–ene–allylic sulfide networks

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Elaboration and characterization of novel polyamide-12-layered titanoniobates nanocomposites

International audienceThis article describes the synthesis and the characterization of a polyamide-12 filled with a nanostructured organic/inorganic titanoniobate hybrid material. The pristine oxide KTiNbO5 has been successfully organomodified by N-alkyl amines via an acido-basic reaction after a cationic exchange step as shown by x-ray diffraction. Transmission electron microscope study and scanning transmission electron microscope observations have been used to describe the change of morphology of the nanofillers before and after processing; the micronic aggregates were changed into single sheets and dispersed in the polymer. Thermomechanical properties of the composites have been determined, and their analyses with structure-properties models are consistent with the exfoliation of the organomodified titanoniobates

Elaboration and characterization of novel polyamide-12-layered titanoniobates nanocomposites

International audienceThis article describes the synthesis and the characterization of a polyamide-12 filled with a nanostructured organic/inorganic titanoniobate hybrid material. The pristine oxide KTiNbO5 has been successfully organomodified by N-alkyl amines via an acido-basic reaction after a cationic exchange step as shown by x-ray diffraction. Transmission electron microscope study and scanning transmission electron microscope observations have been used to describe the change of morphology of the nanofillers before and after processing; the micronic aggregates were changed into single sheets and dispersed in the polymer. Thermomechanical properties of the composites have been determined, and their analyses with structure-properties models are consistent with the exfoliation of the organomodified titanoniobates

Photo-Plasticity in Thiol-ene Network Polymers - A Review

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Polyethylene nanocomposites based on intercalation of N-alkyl amines within KTiNbO5 structure

International audienceThis article describes the synthesis of nanostructured organic/inorganic hybrid materials based on the modification of the titanoniobate oxide KTiNbO5 by N-alkyl amines via an acido-basic reaction. X-ray diffraction and scanning electron microscopy have showed the successful intercalation of the organic molecules between the inorganic layers. The hybrid nanofillers previously obtained have been incorporated in a polyethylene matrix by melt intercalation. The morphology and thermomechanical properties of the nanocomposites have been investigated. It has been revealed that the modification of the oxide improves the dispersion and the exfoliation in the matrix leading to an increase of Young's modulus and of the degradation temperature. The TEM observations coupled with EDS mapping is revealed to be one interesting mean of characterization for this study

Preparation and Flame Retardancy Properties of Novel PA12 and PE/Layered Titanoniobates Nanocomposites

International audienceWe report herein a study performed on a layered titanoniobate KTiNbO5modified by octadecylamine to evaluate the fire retardancy properties of this novelhybrid nanofiller dispersed in PA12 and LLDPE, by polymer melt intercalation. The nano-composites have been characterized using Electron Microscopy techniques to evaluatethe degree of exfoliation and the morphologies. Thermogravimetric analyses and conecalorimeter tests have been carried out toassess the fire retardant performance

Preparation and Flame Retardancy Properties of Novel PA12 and PE/Layered Titanoniobates Nanocomposites

International audienceWe report herein a study performed on a layered titanoniobate KTiNbO5modified by octadecylamine to evaluate the fire retardancy properties of this novelhybrid nanofiller dispersed in PA12 and LLDPE, by polymer melt intercalation. The nano-composites have been characterized using Electron Microscopy techniques to evaluatethe degree of exfoliation and the morphologies. Thermogravimetric analyses and conecalorimeter tests have been carried out toassess the fire retardant performance

Polyethylene nanocomposites based on intercalation of N-alkyl amines within KTiNbO5 structure

International audienceThis article describes the synthesis of nanostructured organic/inorganic hybrid materials based on the modification of the titanoniobate oxide KTiNbO5 by N-alkyl amines via an acido-basic reaction. X-ray diffraction and scanning electron microscopy have showed the successful intercalation of the organic molecules between the inorganic layers. The hybrid nanofillers previously obtained have been incorporated in a polyethylene matrix by melt intercalation. The morphology and thermomechanical properties of the nanocomposites have been investigated. It has been revealed that the modification of the oxide improves the dispersion and the exfoliation in the matrix leading to an increase of Young's modulus and of the degradation temperature. The TEM observations coupled with EDS mapping is revealed to be one interesting mean of characterization for this study

Block copolymers of the type poly(caprolactone)-b-poly(ethylene oxide) for the preparation and stabilization of nanoemulsions

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