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A detailed row by row investigation of major lateral tooth cusp mineralisation, together with the concomitant development of the superior epithelial tissue surrounding the teeth of the chiton Acanthopleura hirtosa has been undertaken using a combination of light microscopy, and scanning and transmission electron microscopy. A holistic approach has been adopted that encompasses observations over a range of spatial scales, from whole radula mineralisation processes to those occurring within individual tooth cusps at various stages of development. In addition, mineralisation in radulae from freshly collected animals has been compared to that of animals maintained for extensive periods within a newly developed iron limited system, which restricts radula mineralisation without impeding the formation of the organic matrix. An evaluation of the iron limitation technique has revealed that maintaining specimens of A. hirtosa within an iron poor environment results in a significant departure from the normal pattern of mineralisation in these animals. As a consequence of iron limitation, there is an obvious increase in the number of unmineralised tooth rows in addition to associated alterations in structure and composition at all stages of tooth development. In normal specimens of A. hirtosa, the onset of mineralisation in the tooth cusps occurs following the prior accumulation of iron at the junction zone and the sudden accumulation of iron containing granules in the cusp epithelium at tooth row 13. The superior epithelium surrounding the tooth cusps undergoes a series of developmental changes leading up to, and following, the onset of mineralisation. In particular, the abundance of mitochondria within the apical cusp epithelium increases, presumably in order to provide the ideal conditions of pH, and thus solubility, needed for the supersaturation of iron and its nucleation at row 13. Once mineralisation has commenced, the microvilli attached to the cusps develop rapidly, and are suggested to do so in order to facilitate the transport of iron, and thereby ensure that a high concentration gradient of this element into the cusps is maintained. The delivery of iron into the cusps occurs from two fronts, the first from the superior epithelium via the posterior surface, and the second from the junction zone via an internal pathway situated along the lepidocrocite boundary between the magnetite and core regions of the tooth. The existence of a plume of elements between this internal mineralisation pathway and the junction zone, provides the first direct evidence that the junction zone is involved in the storage and release of elements for cusp mineralisation. Data from iron limited radulae also indicate that iron continues to be deposited at the junction zone in preference to the superior epithelium or cusps, despite the disruption of mineralisation, highlighting the importance of this region in the mineralisation process. Iron reinstatement experiments have also shown that the internal pathways of iron delivery within the organic matrix remain viable, despite prolonged periods of iron limitation. In addition, the reinstatement of iron has revealed that the plumes, situated between the junction zone and internal mineralising pathway of the cusp, stem from the centre of the plate like junction zone, directly above the stylus canal, a tube like cavity situated within the styli of each major lateral tooth. An in depth study of the stylus canal has revealed that cells within the canal are remarkably similar to those of the epithelium surrounding the cusps, suggesting that this structure may also be involved in the delivery of ions to the junction zone. The stylus canal is shown to be present in the major lateral tooth cusps of 38 chiton species distributed worldwide, and is therefore likely to be a feature common to all chitons. The presence of the canal, and indeed its absence from the bases of all remaining non iron mineralised teeth, irrespective of chiton species, also points strongly to a functional relationship between the stylus canal and tooth cusp mineralisation.

Objetivo: avaliar a influência do conteúdo de BisGMA, TEGDMA e BisEMA sobre tensão de polimerização (spol), grau de conversão (GC), contração volumétrica (CV), módulo de elasticidade (E), escoamento (ES), taxa máxima de reação (RPmax) e incremento máximo de tensão (RSmax) e verificar as possíveis relações de dependência entre a tensão de polimerização e as demais variáveis. Material e métodos: Foram estudadas nove misturas, todas contendo 40% em peso de sílica coloidal, variando a concentração molar de BisGMA (33, 50 ou 66%) e o tipo de comonômero (TEGDMA, BisEMA ou ambos em partes iguais). spol foi determinada pela inserção do compósito (h=1mm) entre bastões de acrílico (r=3mm) fixados às garras de uma máquina universal de ensaios e dividindo-se a máxima força de contração registrada pela secção transversal dos bastões. CV foi mensurada em dilatômetro de mercúrio. E foi obtido através do teste de flexão em três pontos. Fragmentos de espécimes de flexão de cada grupo foram utilizados para análise do GC por FTRaman. O ES foi obtido pela aplicação de uma carga de 20N por 60s sobre o compósito não-polimerizado. RPmax foi determinada por calorimetria exploratória diferencial (DSC). RSmax foi calculado pela diferença entre dois valores de spol consecutivos. Os dados foram submetidos a ANOVA de dois fatores, teste de Tukey (a=0,05%) e análises de regressão. Resultados: A interação entre os fatores foi estatisticamente significante para todas as variáveis avaliadas (p<0,01), com exceção de GC onde apenas os fatores principais foram significantes (p<0,001). Em geral, composições com maior concentração de BisGMA e com o co-monômero BisEMA apresentaram menor GC e ES, o que se refletiu em menores valores para spol, CV e E. RPmax foi semelhante em todos os grupos, com exceção do compósito com 66%TEGDMA, que apresentou valor estatisticamente menor. Entretanto,. esse grupo apresentou o maior valor de RSmax. As análises de regressão evidenciaram forte relação direta de dependência da spol com GC (R2=0,830), ES (R2=0,896), CV (R2=0,690) e RSmax (R2=0,900). A correlação com o E foi fraca (R2=0,404) e com RPmax foi negativa (R2=0,667). Conclusões: Dentre as formulações avaliadas, compósitos contendo BisEMA e aqueles com maiores concentrações de BisGMA apresentaram, em geral, menor spol, GC, CV, ES e E. RPmax foi pouco afetada pela composição da matriz orgânica. spol mostrou maior relação de dependência com os fatores GC, CV e ES. / Objective: To evaluate the influence of BisGMA, TEGDMA and TEGDMA content on polymerization stress (spol), degree of conversion (DC), volumetric shrinkage (VS), elastic modulus (E), flow, maximum polymerization rate (RPmax) and maximum stress rate (RSmax) and to establish the correlation between polymerization stress and the other variables. Materials and Methods: Nine resin mixtures were studied, varying the BisGMA molar concentration (33, 50 or 66%) and the co-monomer content (TEGDMA, BisEMA or both in equal parts). All blends received 40 wt % of colloidal silica. spol was determined by inserting the composite (h=1mm) between acrylic rods (r=3mm) fixed on the opposite ends of a universal testing machine, and dividing the maximum contraction force by the rods? cross section. VS was measured by mercury dilatometry. E was obtained by three-point bending test. Fragments of flexural specimens were used to analyze DC by FT-Raman. Flow was obtained applying load of 20N for 60s on the uncured composite. RPmax was determined by differential scanning calorimetry (DSC). RSmax was calculated by the difference between two consecutives spol values. Data were submitted to two-way ANOVA, Tukey´s test (a=0.05%) and regression analyses. Results: The interactions between factors were significant for all variables (p<0.01), except for DC, where only the main factors were significant (p<0.001). In general, composites with higher BisGMA concentration and those containing BisEMA showed lower DC and flow, which resulted in lower values of spol, VS and E. RPmax was similar for all groups, except for the 66%TEGDMA composite, which showed a statistically lower value. However, this group showed the highest value of RSmax. The regression analyses evidenced a strong direct dependence of spol to DC (R2=0.830), flow (R2=0.896), VS (R2=0.690) and RSmax (R2=0.900). The correlation with E was weak (R2=0.404) and with RPmax was negative (R2=0.667). Conclusion: For the monomer mixtures studied, composites with BisEMA and those with higher BisGMA concentration showed, in general, lower spol, DC, VS, flow and E. RPmax was almost insensitive to the organic matrix composition. spol showed stronger dependence with DC, VS and flow.

Objetivo: avaliar a influência do conteúdo de BisGMA, TEGDMA e BisEMA sobre tensão de polimerização (spol), grau de conversão (GC), contração volumétrica (CV), módulo de elasticidade (E), escoamento (ES), taxa máxima de reação (RPmax) e incremento máximo de tensão (RSmax) e verificar as possíveis relações de dependência entre a tensão de polimerização e as demais variáveis. Material e métodos: Foram estudadas nove misturas, todas contendo 40% em peso de sílica coloidal, variando a concentração molar de BisGMA (33, 50 ou 66%) e o tipo de comonômero (TEGDMA, BisEMA ou ambos em partes iguais). spol foi determinada pela inserção do compósito (h=1mm) entre bastões de acrílico (r=3mm) fixados às garras de uma máquina universal de ensaios e dividindo-se a máxima força de contração registrada pela secção transversal dos bastões. CV foi mensurada em dilatômetro de mercúrio. E foi obtido através do teste de flexão em três pontos. Fragmentos de espécimes de flexão de cada grupo foram utilizados para análise do GC por FTRaman. O ES foi obtido pela aplicação de uma carga de 20N por 60s sobre o compósito não-polimerizado. RPmax foi determinada por calorimetria exploratória diferencial (DSC). RSmax foi calculado pela diferença entre dois valores de spol consecutivos. Os dados foram submetidos a ANOVA de dois fatores, teste de Tukey (a=0,05%) e análises de regressão. Resultados: A interação entre os fatores foi estatisticamente significante para todas as variáveis avaliadas (p<0,01), com exceção de GC onde apenas os fatores principais foram significantes (p<0,001). Em geral, composições com maior concentração de BisGMA e com o co-monômero BisEMA apresentaram menor GC e ES, o que se refletiu em menores valores para spol, CV e E. RPmax foi semelhante em todos os grupos, com exceção do compósito com 66%TEGDMA, que apresentou valor estatisticamente menor. Entretanto,. esse grupo apresentou o maior valor de RSmax. As análises de regressão evidenciaram forte relação direta de dependência da spol com GC (R2=0,830), ES (R2=0,896), CV (R2=0,690) e RSmax (R2=0,900). A correlação com o E foi fraca (R2=0,404) e com RPmax foi negativa (R2=0,667). Conclusões: Dentre as formulações avaliadas, compósitos contendo BisEMA e aqueles com maiores concentrações de BisGMA apresentaram, em geral, menor spol, GC, CV, ES e E. RPmax foi pouco afetada pela composição da matriz orgânica. spol mostrou maior relação de dependência com os fatores GC, CV e ES. / Objective: To evaluate the influence of BisGMA, TEGDMA and TEGDMA content on polymerization stress (spol), degree of conversion (DC), volumetric shrinkage (VS), elastic modulus (E), flow, maximum polymerization rate (RPmax) and maximum stress rate (RSmax) and to establish the correlation between polymerization stress and the other variables. Materials and Methods: Nine resin mixtures were studied, varying the BisGMA molar concentration (33, 50 or 66%) and the co-monomer content (TEGDMA, BisEMA or both in equal parts). All blends received 40 wt % of colloidal silica. spol was determined by inserting the composite (h=1mm) between acrylic rods (r=3mm) fixed on the opposite ends of a universal testing machine, and dividing the maximum contraction force by the rods? cross section. VS was measured by mercury dilatometry. E was obtained by three-point bending test. Fragments of flexural specimens were used to analyze DC by FT-Raman. Flow was obtained applying load of 20N for 60s on the uncured composite. RPmax was determined by differential scanning calorimetry (DSC). RSmax was calculated by the difference between two consecutives spol values. Data were submitted to two-way ANOVA, Tukey´s test (a=0.05%) and regression analyses. Results: The interactions between factors were significant for all variables (p<0.01), except for DC, where only the main factors were significant (p<0.001). In general, composites with higher BisGMA concentration and those containing BisEMA showed lower DC and flow, which resulted in lower values of spol, VS and E. RPmax was similar for all groups, except for the 66%TEGDMA composite, which showed a statistically lower value. However, this group showed the highest value of RSmax. The regression analyses evidenced a strong direct dependence of spol to DC (R2=0.830), flow (R2=0.896), VS (R2=0.690) and RSmax (R2=0.900). The correlation with E was weak (R2=0.404) and with RPmax was negative (R2=0.667). Conclusion: For the monomer mixtures studied, composites with BisEMA and those with higher BisGMA concentration showed, in general, lower spol, DC, VS, flow and E. RPmax was almost insensitive to the organic matrix composition. spol showed stronger dependence with DC, VS and flow.

Mollusk shells contain proteins within and between the crystals of calcium carbonate. These organic molecules play an important role in biomineralization and shell function, and their stable isotope ratios of carbon and nitrogen are also thought to record important ecological information about the animal's diet and nutrient sources. These proteins can be preserved for millions of years, offering potential insight into pre-anthropogenic ecological conditions. However, shell organics in older shells are typically recovered in reduced abundances due to leaching and remaining organics are often converted from insoluble proteins to soluble, free amino acids, making them difficult to detect and recover. Therefore, demineralization and organics-capture methods must be optimized for yield to extract much-needed ecological information from older shells. This project compared insoluble and soluble organic yields of modern gastropod Strombus alatus shells demineralized with acids of varying concentrations and temperatures. Results suggested that demineralizing shell fragments with 0.1 M HCl at a ratio of 0.9 L HCl/g of shell was optimal. Average percent organic yields ~0.2% for modern and ~0.06% for fossil Strombus spp. Future applications of this work include using this refined method to reconstruct food webs across broad temporal scales.

L’objectif principal de cette thèse était d’identifier et de quantifier les protéines de la matrice organique qui contrôlent le type polymorphique et la morphologie des cristaux présents dans la coquille d’oeuf de poule à différents stades du processus de minéralisation afin de mettre en évidence les composants impliqués dans la calcification à chacun de ces stades. Au total, 64 et 175 protéines différentiellement abondantes durant le processus de minéralisation ont été identifiées dans le milieu de formation (fluide utérin) et la matrice organique. Parmi celles-ci, les fonctions de 24 protéines du fluide utérin et de 77 issues de la coquille sont potentiellement reliées au processus de minéralisation. Nous décrivons plus particulièrement 20 protéines du fait de leur abondance et de leurs fonctions directe ou indirecte sur le processus de calcification. Des études complémentaires sur ces candidats permettront de confirmer leur implication dans la minéralisation de la coquille d’oeuf. / The aim of this PhD was to identify and quantify eggshell organic matrix proteins which control polymorphic type and morphology of crystals at different time points of the eggshell mineralization process in order to highlight particular components involved in calcification at each calcification stage. A total of 64 and 175 proteins differentially abundant during mineralization process were identified in the forming milieu (uterine fluid) and in the eggshell organic matrix respectively. Out of them, 24 uterine fluid and 77 eggshell proteins are functionally related to the mineralization process. We paid particular attention to 20 overabundant proteins with direct or indirect functional evidences related to calcification. Further studies will be necessary to confirm their involvement in the chicken eggshell mineralization.

Objetivo: avaliar a relação de dependência da tensão de polimerização (TP), grau de conversão (GC), taxa máxima de reação de polimerização (Rpmax), contração volumétrica (CV), módulo de elasticidade (E) e tangente de delta (tan) com o conteúdo inorgânico e proporção de BisGMA:TEGDMA e verificar as possíveis relações de dependência entre a TP e as demais variáveis-resposta. Material e métodos: Foram preparadas vinte formulações, com concentrações de carga de 40, 50, 60 ou 70 % em peso de vidro de bário e proporções molares de BisGMA:TEGDMA de 3:7, 4:6, 5:5, 6:4 ou 7:3. TP (n=7) foi determinada pela inserção do compósito entre bastões de acrílico fixados às garras de uma máquina universal de ensaios e dividindo-se a máxima força de contração registrada pela secção transversal dos bastões. GC e Rpmax foram determinados por espectroscopia no infra-vermelho próximo (n=5). CV foi mensurada em dilatômetro de mercúrio (n=3). E foi obtido através do teste de flexão em três pontos (n=10). Tan foi determinada por nanoidentação dinâmica (n=3). Foram realizadas análises de regressão para avaliar a influência da fração inorgânica e da proporção monomérica nas variáveis estudadas e para avaliar o efeito das variáveis-resposta na determinação da TP. Resultados: Todas as variáveis se mostraram dependentes da concentração inorgânica e conteúdo monomérico. TP, GC e Rpmax foram mais influenciados pela matriz, enquanto que CV, E e tan apresentaram maior efeito da concentração de carga. TP mostrou-se dependente dos fatores CV e GC. Conclusões: a formulação de compósitos com baixa TP deve observar criteriosamente a fração inorgânica e o conteúdo monomérico, sendo o principal desafio encontrar formulações com baixa CV, uma vez que os demais fatores demonstraram não ter influência significativa e o GC do material não deve ser sacrificado com o propósito de reduzir a TP. / Objective: To evaluate the dependence relationship of polymerization stress (PS), degree of conversion (DC), maximum polymerization rate (Rpmax), volumetric shrinkage (VS), elastic modulus (E) and loss tangent (tan) with the inorganic content and BisGMA:TEGDMA ratio and verify possible relationship among PS and the others variables. Materials and Methods: twenty resin composites were studied, having barium glass concentration of 40, 50, 60 or 70 wt% and BisGMA:TEGDMA molar ratio of 3:7, 4:6, 5:5, 6:4 or 7:3. PS (n=7) was determined inserting the composite between acrylic rods fixed to clamps of an universal test machine and dividing the maximum load recorded by the rods cross-sectional area. DC and Rpmax were determined by near infrared spectroscopy in real time (n=5). VS was measured by mercury dilatometer (n=3). E was obtained by three-point bending test (n=10). Tan was determined by dynamic nanoindentation (n=3). Regression analyses were performed to evaluate the relationship of inorganic content and monomeric ratio on studied variables and to evaluate the effect of the variables on the polymerization stress development. Results: All variables showed dependence on inorganic concentration and monomeric content. PS, DC and Rpmax were more affected by resin matrix whereas VS, E and Tan were more strongly influenced by filler fraction. PS was dependent on both volumetric shrinkage and degree of conversion. Conclusions: in order to obtain composites formulations which provide low polymerization, the inorganic concentration and monomeric contend have to be carefully observed. The main challenge is to design formulations with low VS since the others factors apparently do not have significance and PS should not come at the expense of DC.

Objetivo: avaliar a relação de dependência da tensão de polimerização (TP), grau de conversão (GC), taxa máxima de reação de polimerização (Rpmax), contração volumétrica (CV), módulo de elasticidade (E) e tangente de delta (tan) com o conteúdo inorgânico e proporção de BisGMA:TEGDMA e verificar as possíveis relações de dependência entre a TP e as demais variáveis-resposta. Material e métodos: Foram preparadas vinte formulações, com concentrações de carga de 40, 50, 60 ou 70 % em peso de vidro de bário e proporções molares de BisGMA:TEGDMA de 3:7, 4:6, 5:5, 6:4 ou 7:3. TP (n=7) foi determinada pela inserção do compósito entre bastões de acrílico fixados às garras de uma máquina universal de ensaios e dividindo-se a máxima força de contração registrada pela secção transversal dos bastões. GC e Rpmax foram determinados por espectroscopia no infra-vermelho próximo (n=5). CV foi mensurada em dilatômetro de mercúrio (n=3). E foi obtido através do teste de flexão em três pontos (n=10). Tan foi determinada por nanoidentação dinâmica (n=3). Foram realizadas análises de regressão para avaliar a influência da fração inorgânica e da proporção monomérica nas variáveis estudadas e para avaliar o efeito das variáveis-resposta na determinação da TP. Resultados: Todas as variáveis se mostraram dependentes da concentração inorgânica e conteúdo monomérico. TP, GC e Rpmax foram mais influenciados pela matriz, enquanto que CV, E e tan apresentaram maior efeito da concentração de carga. TP mostrou-se dependente dos fatores CV e GC. Conclusões: a formulação de compósitos com baixa TP deve observar criteriosamente a fração inorgânica e o conteúdo monomérico, sendo o principal desafio encontrar formulações com baixa CV, uma vez que os demais fatores demonstraram não ter influência significativa e o GC do material não deve ser sacrificado com o propósito de reduzir a TP. / Objective: To evaluate the dependence relationship of polymerization stress (PS), degree of conversion (DC), maximum polymerization rate (Rpmax), volumetric shrinkage (VS), elastic modulus (E) and loss tangent (tan) with the inorganic content and BisGMA:TEGDMA ratio and verify possible relationship among PS and the others variables. Materials and Methods: twenty resin composites were studied, having barium glass concentration of 40, 50, 60 or 70 wt% and BisGMA:TEGDMA molar ratio of 3:7, 4:6, 5:5, 6:4 or 7:3. PS (n=7) was determined inserting the composite between acrylic rods fixed to clamps of an universal test machine and dividing the maximum load recorded by the rods cross-sectional area. DC and Rpmax were determined by near infrared spectroscopy in real time (n=5). VS was measured by mercury dilatometer (n=3). E was obtained by three-point bending test (n=10). Tan was determined by dynamic nanoindentation (n=3). Regression analyses were performed to evaluate the relationship of inorganic content and monomeric ratio on studied variables and to evaluate the effect of the variables on the polymerization stress development. Results: All variables showed dependence on inorganic concentration and monomeric content. PS, DC and Rpmax were more affected by resin matrix whereas VS, E and Tan were more strongly influenced by filler fraction. PS was dependent on both volumetric shrinkage and degree of conversion. Conclusions: in order to obtain composites formulations which provide low polymerization, the inorganic concentration and monomeric contend have to be carefully observed. The main challenge is to design formulations with low VS since the others factors apparently do not have significance and PS should not come at the expense of DC.

Ce travail de thèse, en partenariat avec l’entreprise ALSTOM, s’inscrit dans une logique de remplacement de pièces industrielles en alliage métallique par des pièces composites pour l’allègement des structures. L’objectif est de contribuer à l’écriture de règles de dimensionnement permettant au partenaire industriel de certifier des pièces structurales annulaires réalisées en composite à matrice thermoplastique thermostable (TPTS) renforcée par des fibres de carbone pour des applications embarquées sur machine tournante. Il s’agit plus exactement de déterminer la durée de vieen fatigue de ces pièces, en particulier en présence d’endommagement, et lorsque celles -ci sont soumises aux chargements inertiels et thermiques de service.Au cours de ce travail de thèse, une méthodologie a été développée afin de répondre à cette demande. La stratégie a consisté à reproduire,à l’échelle d’éprouvettes de laboratoire, l’état de contrainte multi-axial et l’endommagement auxquels la structure industrielle est soumise, et ce en développant et optimisant un essai de traction sur des éprouvettes annulaires entaillées. Les essais multi axiaux plus classiques mettant en œuvre des sollicitations par pression interne présentent effectivement de nombreux problèmes techniques et sécuritaires lorsqu’ils doivent être mis en œuvre à chaud.Une fois la configuration d’essai sur anneau optimisé par simulation numérique, des essais ont été réalisés afin de confirmer l’apparition des endommagements escomptés à l’aide de techniques de contrôle non-destructif. Les essais cycliques réalisés dans cette configuration ont montré une excellente résistance du matériau en fatigue, en particulier pour un ratio de chargement R de 0.5, proche des conditions de service. Les résultats ont également soulignés le fort potentiel restant de ces structures, même après un grand nombre de cycles de chargement. / The objective of this thesis work, in partnership with ALSTOM Company, is to contribute to the writing of design rules in order to qualify and certify annular structures made of thermostable thermoplastic matrix composite reinforced by carbon fibre. These structures are used in rotating machines for embedded applications.This work proposes an innovative methodology to achieve this goal. It consists in reproducing, at the scale of a laboratory specimen, the multiaxial stress and damage states to which the industrial structure is subjected in-service byoptimizing a tensile test on annular notched specimen. More conventional multiaxial tests, based on internal pressureand tensile loading are particularly unsafe and difficult to be performedwhen implemented at elevated temperature.After the optimisation of the ring configuration by numerical simulation, experimental tests were performed to validatethe appearance of the expected damage under loading. Damage was characterized using non-destructive techniques suchas acoustic emission and infrared thermography. The cyclic tests achieved using this configuration showed high fatiguestrength of this material, in particular for a ratio R of 0.5 (equivalent to thein-service ratio). The results also highlight thegreat remaining strength and rigidity of these structures, even after a large number of cycles.

Les matériaux composites à matrice organique sont de plus en plus utilisés par l'industrie des transports pour la réalisation d'éléments structuraux. Afin de permettre un dimensionnement optimal de ces structures, il est nécessaire d'améliorer la compréhension et la modélisation du comportement de ces matériaux sur une large gamme de vitesses de sollicitation et de températures d'environnement. Pour cela, plusieurs campagnes expérimentales ont été réalisées sur le T700GC/M21, un composite stratifié à matrice organique, dans le cadre de ces travaux. Tout d'abord, des essais dynamiques sur un vérin hydraulique, ainsi que des essais de fluage, ont été menés afin de caractériser la dépendance à la vitesse du comportement de ce matériau. Ensuite, la dépendance à la température a été mise en évidence à l'aide d'essais à basse température sur vérin hydraulique, complétés d'essais DMA.Les résultats de ces essais ont été utilisés afin de justifier physiquement le développement d'un modèle visco-élastique bi-spectral pour la description de la dépendance à la vitesse du T700GC/M21 sur une large gamme de vitesses de déformation. L'influence de la température d'environnement sur le comportement a quant à elle été introduite à l'aide d'une loi d'Arrhénius. Ce modèle thermo-visco-élastique permet finalement de rendre compte du comportement du stratifié T700GC/M21 sur une large gamme de vitesses et de températures / Organic matrix composite materials are more and more used in the transportation industry to design strutural components. In order to reach an optimal design, improvements in the understanding and the modelling of the behaviour of these materials under various strain rates and temperatures conditions are required.Therefore, a campaign of various mechanical tests has been performed on the T700GC/M21 organic matrix composite laminate in this work. On one hand, dynamic tests have been performed using hydraulic jacks, as well as creep tests, to characterise the material strain rate dependency. On the other hand, low temperatures and DMA tests have been performed to exhibit the temperature effect.Experimental results have been used to physically justify a bi-spectral visco-elactic model which describes the strain rate dependency of T700GC/M21 on a large range of strain rates. Introducing an Arrhenius like law for the viscous mechanisms, the temperature dependency has also been taken into account. The obtained thermo-visco-elastic model finally describes the behaviour of the T700GC/M21 laminate on a large range of strain rates and temperatures