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| Registros recuperados: 13 | |
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| Le Duigou, Antoine; Baley, Christophe; Grohens, Yves; Davies, Peter; Cognard, Jean Yves; Creach Cadec, Romain; Sohier, Laurent. |
| A significant recent development in the composite field is the appearance of biocomposites (biopolymers reinforced by plant fibres) which combine mechanical performance and low environmental impacts. However, to replace conventional composites a significant effort is needed to understand their mechanical behaviour under complex loading (both in-plane and out-of-plane). The interfacial behaviour (fibre/matrix) of these materials also requires particular attention in order to optimize mechanical properties. With this aim modified Arcan, transverse tension and microdroplet debonding tests have been performed on flax reinforced PLLA biocomposites, as very few data of this type are available. The out-of-plane tensile and tensile-shear properties of these... |
| Tipo: Text |
Palavras-chave: A natural fibre composites; B interfacial properties; B out-of-plane properties; B microbond test. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00197/30857/29222.pdf |
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| Deroine, Morgan; Le Duigou, Antoine; Corre, Yves-marie; Le Gac, Pierre-yves; Davies, Peter; Cesar, Guy; Bruzaud, Stephane. |
| Accelerated ageing was performed in distilled water at different temperatures (25, 30, 40 and 50°C) on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), which is a biodegradable biopolymer, in order to estimate its lifetime in aqueous environment. In a first part, degradation mechanisms were followed by gravimetry, tensile tests and steric exclusion chromatography. Both immersion and relative humidity have been examined. In a second part, the strain at break was used as an indicator for lifetime prediction with an Arrhenius extrapolation. The study revealed the presence of only one irreversible degradation mechanism, i.e. hydrolytic degradation, which is temperature dependant. So, within the approach assumptions, the lifetime in distilled water of PHBV... |
| Tipo: Text |
Palavras-chave: Poly(3-hydroxybutyrate-co-3-hydroxyvalerate); Accelerated ageing; Hydrothermal degradation; Lifetime prediction. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00203/31396/29785.pdf |
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| Deroine, Morgan; Le Duigou, Antoine; Corre, Yves-marie; Le Gac, Pierre-yves; Davies, Peter; Cesar, Guy; Bruzaud, Stephane. |
| Pollution of nature by plastics is a major environmental problem and the challenge for the future is to manage the lifetime of polymers better. The aim of this study is to establish a baseline on degradation mechanism and degradation kinetics for lifetime prediction of polylactide (PLA) in a marine environment. The ageing of PLA was accelerated by raising temperature in distilled water, filtered and renewed seawater and natural seawater. Samples were immersed in distilled water for six months at different temperatures (25, 30, 40 and 50°C) in order to evaluate the influence of temperature on PLA degradation kinetics and to predict lifetime. Then, samples were immersed in seawater both in the laboratory and at sea, in order to compare the effects of... |
| Tipo: Text |
Palavras-chave: PLA; Accelerated ageing; Hydrothermal ageing; Degradation. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00173/28376/26689.pdf |
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| Le Duigou, Antoine; Pillin, Isabelle; Bourmaud, Alain; Davies, Peter; Baley, Christophe. |
| The biocompostability of natural fibre-reinforced biopolymers, also known as biocomposites, makes them an attractive alternative to glass fibre-reinforced petrochemical polymers. The aim of this work is to study the capacity of flax/PLLA (poly(L-lactide)) biocomposite (20% and 30% fibres by weight) to be recycled. Mechanical properties were evaluated initially, and shown to be similar to those of glass/PP and superior to hemp/PP and sisal/PP composites. Then after repeated injection cycles tensile properties were shown to be conserved until the third cycle. Matrix degradation and fibre aspect ratio were followed using molecular weight measurements, thermal and rheological analyses, image analysis of sections and SEM fractography. These techniques revealed... |
| Tipo: Text |
Palavras-chave: Mechanical properties; Recycling; Flax fibres; PLLA. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6360.pdf |
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| Le Duigou, Antoine; Davies, Peter; Baley, Christophe. |
| The influence of wet aging on the behaviour of flax/epoxy micro-composites composed of single flax fibres embedded in epoxy micro-droplets has been studied. Interfacial shear strength has been examined by debonding the micro-droplets. The apparent interfacial shear strength decreases with immersion time in water, dropping rapidly during the first 15 min of immersion then stabilizing. Drying samples after short immersion periods allows recovery of properties, indicating a plasticization mechanism. For longer immersion times irreversible degradation is observed. Scanning electron microscopy reveals fibre surface peeling, indicating that an internal interface within the fibre is weaker than the fibre/matrix interface after aging. A simple descriptive model... |
| Tipo: Text |
Palavras-chave: Flax fibres; Environmental degradation; Fibre/matrix bond. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00137/24829/23101.pdf |
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| Baley, Christophe; Kervoelen, Antoine; Lan, Marine; Cartie, Denis; Le Duigou, Antoine; Bourmaud, Alain; Davies, Peter. |
| Automated fibre placement (AFP) has been used to manufacture flax/polypropylene biocomposites for the first time. This required preparation of tape with a calibrated width from impregnated fibre sheets. The unidirectional tapes showed polymer-rich zones on the surface. During manufacture the polypropylene (PP) is melted locally with a laser. A consolidation step in a hot press is then required to reduce void content. The flax fibres, composed of polysaccharides, have limited thermal resistance so optimization of the thermal cycle is necessary, but subsequent characterization of mechanical behaviour showed no evidence of property loss in spite of an additional melting cycle. AFP appears to be a promising manufacturing method for biocomposites. |
| Tipo: Text |
Palavras-chave: Structural composites; AFP; Biocomposites; Flax; PP. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00307/41800/41009.pdf |
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| Le Duigou, Antoine; Merotte, Justin; Bourmaud, Alain; Davies, Peter; Belhouli, Karim; Baley, Christophe. |
| The present article aims to investigate the contribution of hygroscopic expansion of flax fibres to interfacial radial stresses and Interfacial Shear Strength (IFSS) of Maleic Anhydride grafted PolyPropylene (MAPP)/Flax biocomposites. During manufacturing of thermoplastic biocomposites and storage at 50% RH, a weight variation is observed, attributed to water content evolution within plant cell-walls. The hygroscopic radial expansion coefficient βr flax of single flax fibres estimated by Environmental Scanning Electron Microscopy (ESEM) observation is many orders of magnitude higher (βf,R = 1.14 ε/Δm) than thermal expansion (αf, R = 78 10−6 ε/°C). Thus, its contribution to the development of residual stresses σrad during processing should be prevalent. A... |
| Tipo: Text |
Palavras-chave: Flax fibres; Fibre/matrix bond. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00397/50830/51594.pdf |
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| Le Duigou, Antoine; Davies, Peter; Baley, Christophe. |
| The use of glass fibre reinforced polyester composites raises many health and safety and environmental questions. One alternative is the development of high performance bio-based bio-composites with low environmental impact. Improved understanding of interfacial properties is essential to optimise the mechanical properties and durability of these materials, but so far few data are available. The present work describes the interfacial characterization of Flax fibre/Poly(lactic) acid (PLLA) system at the micro-scale using the microbond test. Different thermal treatments have been carried out (cooling rate and annealing) in order to evaluate the influence of matrix and interfacial morphologies as well as residual stress on interfacial properties.... |
| Tipo: Text |
Palavras-chave: Flax fibre; Biopolymer; Biocomposite; Interfacial properties; Microbond test. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00000/11161/7808.pdf |
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| Le Duigou, Antoine; Bourmaud, Alain; Davies, Peter; Baley, Christophe. |
| Innovation in sailing yacht design must include current environmental concerns such as resource depletion and waste management. Indeed most of the materials used today are petro-based and cannot offer viable end of life treatment. Fully biodegradable natural fibre reinforced biopolymers are being increasingly studied as they offer high specific stiffness and low environmental footprint. However, their ageing mechanisms are still not well understood. The present article gives information on 2 years natural seawater aging effect on injection-molded Flax/PLA biocomposite. Biocomposites suffer from relatively high moisture absorption which is controlled by the vegetal fibres. Simple rules of mixtures allow the determination of weight gain for flax fibres which... |
| Tipo: Text |
Palavras-chave: Natural fibre composites; Seawater ageing; Damage mechanism. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00211/32191/30681.pdf |
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| Bourmaud, Alain; Mérotte, Justin; Siniscalco, David; Le Gall, Maelenn; Gager, Victor; Le Duigou, Antoine; Pierre, Floran; Behlouli, Karim; Arnould, Olivier; Beaugrand, Johnny; Baley, Christophe. |
| This paper investigates biochemical, morphological and mechanical properties of a large range of plant fibres explored with the same methods. Biochemical results clearly exhibit strong differences between gelatinous, i.e. flax and hemp, and xylan type, i.e. jute and kenaf, cell walls. These differences into parietal composition have an impact on cell wall stiffness, highlighted through nanoindentation and atomic force microscopy measurements, but also on fibre individualisation, due to variations into fibre bundles cohesion. In addition, the morphology and particularly the lumen size induces apparent density differences. Moreover, the influence of fibre morphology and properties is demonstrated on UD materials. Finally, longitudinal Young’s modulus of each... |
| Tipo: Text |
Palavras-chave: Natural fibers; Biocomposite; Microstructures; Mechanical properties. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00505/61621/65646.pdf |
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| Deroine, Morgan; Cesar, Guy; Le Duigou, Antoine; Davies, Peter; Bruzaud, Stephane. |
| In this study, natural degradation and biodegradation of poly(3-hydroxybuyrate-co-3-hydroxyvalerate) (PHBV) films were followed in different marine environments. First of all, ageing of PHBV films was investigated in natural seawater for 180 days and degradation was followed by means of weight loss measurements, scanning electron microscopy (SEM), differential scanning calorimetry and steric exclusion chromatography. In a second part, biodegradation tests were performed on PHBV powder, by following carbon dioxide (CO2) release(,) to highlight the PHBV bioassimilation of marine microorganisms. Three different marine environments were considered for biodegradation tests: a solid inoculum with foreshore sand, a solid-liquid inoculum with sand and seawater and... |
| Tipo: Text |
Palavras-chave: PHBV; Natural ageing; Degradation; Biodegradation; Seawater. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00296/40735/42020.pdf |
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| Deroine, Morgan; Le Duigou, Antoine; Corre, Yves-marie; Le Gac, Pierre-yves; Davies, Peter; Cesar, Guy; Bruzaud, Stephane. |
| The aim of this study is to establish a baseline for poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) lifetime prediction in a marine environment, by means of mechanical and physico-chemical characterization of specimens immersed in continuously renewed and filtered natural seawater in the laboratory at different temperatures (4, 25 and 40°C). Samples were also aged at sea in Lorient harbour in order to compare laboratory and natural degradation mechanisms and kinetics. Due to its morphology, hydrolysis of PHBV in natural seawater is quite slow, and samples were observed to undergo preferentially an enzymatic surface degradation. Increasing the aging temperature in the laboratory promotes the water uptake and causes hydrolysis. As two degradation... |
| Tipo: Text |
Palavras-chave: Poly(3-hydroxybutyrate-co-3-hydroxyvalerate); Accelerated ageing; Hydrothermal degradation; Seawater. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00188/29972/28425.pdf |
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| Baley, Christophe; Gomina, Moussa; Breard, Joel; Bourmaud, Alain; Drapier, Sylvain; Ferreira, Manuela; Le Duigou, Antoine; Liotier, Pierre Jacques; Ouagne, Pierre; Soulat, Damien; Davies, Peter. |
| The use of composite materials reinforced by flax fibres has been increasing steadily over the last 20 years. These fibres show attractive mechanical properties but also some particularities (naturally limited length, presence of a lumen, fibres grouped in bundles in the plant, complex surface properties and composition). An analysis of the available literature indicates that the quality of the composite materials studied is not always optimal (high porosity, incomplete impregnation, heterogeneous microstructure, variable fibre orientation). This paper reviews published data on the specific nature of flax fibres with respect to manufacturing of biocomposites (defined here as polymers reinforced by natural fibres). All the important steps in the process... |
| Tipo: Text |
Palavras-chave: Composite materials; Biocomposite; Flax fibre; Polymer; Processing. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00473/58429/61027.pdf |
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| Registros recuperados: 13 | |
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