Publications by Yves Leterrier

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

The effect of internal stresses on the cohesion and adhesion of a thin silicon oxide (SiOx) oxygen-barrier coating, evaporated on a poly(ethylene terephthalate) (PET) film substrate was studied. Internal stresses were generated during annealing in the temperature range for recrystallization of the PET,during calendering in a multilayer structure where two SiOx/PET films were laminated together with a polypropylene film, and during long-term thermal aging below the glass transition temperature of the polymer

The potential of pulp fiber reinforced thermoplastics is currently not fully explored in composites. One of the main reasons is that pulp fibers are extracted for the use in papermaking and are thus not optimized for use as reinforcements in thermoplastics. Furthermore, currently used processing methods constitute several severe thermomechanical steps inducing premature degradation of the fibers. A systematic development of these composite materials requires the study of both these aspects. The goal of this

Thin brittle films on polymer substrates are finding increasing use as gas barriers for example in the medical and food packaging industries and also for the next generation of ultra-light displays based on flexible polymer substrates. In order to determin ...

The reinforcement potential of pulp fibres is presently not fully explored in thermoplastic composites. One of the reasons is that currently used processing methods comprise several severe thermomechanical steps inducing premature degradation of the fibres. Three pre-forming techniques were developed to prepare pulp fibre reinforced cellulose diacetate (CDA) pre-forms, namely filtration-forming, solvent impregnation, and commingling with polymer fibres. These techniques eliminate all thermomechanical steps,

Among the century’s main challenges, climate change and the need for energy sources diversification are of great importance. In this context, renewable energies undoubtedly have an important role to play. Photovoltaic (PV) electricity is especially well suited to face these energy challenges. It is now established that the low thin film photovoltaic panels production costs will allow, even in continental climate, to reach low electricity cost, providing easy installation, public acceptance and high reliabil

This work evaluated the possibility of using silicon solar cells as load-carrying elements in composite sandwich structures. Such an ultra-light multifunctional structure is a new concept enabling weight, and thus energy, to be saved in high-tech applicati ...

Crack onset strain measurements of a confined layer in tension provide the means for layer toughness estimation. The procedure can be simplified if steady-state conditions prevail starting from the commencement of crack propagation, an assumption frequentl ...

The present work investigated the effects of physical aging on interfacial adhesion and internal stresses using single-fibre model composites. First, the stress state of the interface and its evolution upon aging were studied for the microbond geometry. This stress analysis was used with experiments to determine an intrinsic interfacial shear strength. Second, this stress analysis, including aging effects, was used in a fracture mechanics or energy release rate analysis of the microbond test, which involves

This article aims to determine the environmental performance of China reed fibre used as a substitute for glass fibre as reinforcement in plastics and to identify key environmental parameters. A life cycle assessment (LCA) is performed on these two materials for an application to plastic transport pallets. Transport pallets reinforced with China reed fibre prove to be ecologically advantageous if they have a minimal lifetime of 3 years compared with the 5-year lifetime of the conventional pallet. The energy

The rheological properties in solution, in shear and in uniaxial elongation of poly(ethylene terephthalate) (PET) reacted together with hyperbranched polymers (HBPs) were investigated. Two different PET grades, of low and high molecular weights, were compounded with sub- to over-stoichiometric concentrations of HBPs of second and fourth pseudo-generation, and subsequently subjected to a solidstate polycondensation (SSP). The formation of microgels, which occurs at high HBP concentration, gave rise to a larg

Maintaining electrical conductivity, optical transparency, and mechanical integrity against bending and stretching are key requirements for flexible transparent electrodes. Transparent conducting oxides (TCOs) are widely used thin film electrodes in optoel ...

Thin silicon oxide (SiOx) barrier coatings formed by plasma enhanced chemical vapor deposition on poly(ethylene terephthalate) (PET) substrates were subjected to post-deposition annealing treatments in the temperature range for orientation relaxation of th ...

Extending the useful life of materials through recycling has proven to be an efficient means of reducing natural resource use and limiting the production of waste. In the case of polymer-based materials, in general, and of packaging materials, in particular, material recovery is complicated by the presence of incompatible polymers, as well as a priori undesirable contaminants such as inorganic inclusions. This article investigated the recycling of multilayer packaging material systems, based on polypropylen

Research on silicon oxide thin films developed as gas-barrier protection for polymer-based components is reviewed, with attention paid to the relations between (i) coating defects, cohesive strength and internal stress state, and (ii) interfacial interactions and related adhesion to the substrate. The deposition process of the oxide from a vapor or a plasma phase leads in both cases to the formation of covalent bonds between the two materials, with high adhesion levels. The oxide coating contains nanoscopic

The photo-curing behavior of composites containing nanosized SiO2 in an acrylated hyperbranched polymer matrix was investigated by means of photo differential scanning calorimetry. The chemical conversion data were analyzed using an autocatalytic model, pa ...

Uniaxial fragmentation tests were carried out in situ in a scanning electron microscope (SEM) on 10-nm-thick silicon oxide coatings deposited by plasma enhanced chemical vapor deposition on poly(ethylene terephthalate). In order to prevent charging effects due to the isolating nature of the oxide surface, an additional conductive gold layer was sputtered onto the coating prior to its tensile loading in the SEM chamber. The gold layer was shown not to affect initiation of tensile failure of the oxide coating

Light-trapping textures were produced in hyperbranched polymer (HBP) silica nanocomposites using a UV-nanoimprint lithography (UVNIL) replication method, either in batch or roll-to-roll processes. The hardness of the HBP was found to increase by a factor o ...

The effect of silylation of microfibrillated cellulose (MFC) surfaces on β‐phase formation in poly(vinylidene difluoride) (PVDF) and the resulting viscoelastic and dielectric performance of MFC‐PVDF composites is investigated. Two different organosilanes, ...

As part of a project that aims to provide people with disabilities with simple assistive devices in Colombia, the possibility of creating a PET filament that can be printed by Fused Deposition Modelling (FDM) from beverage bottle waste was investigated, wi ...

Functionally graded epoxy composites with various concentration profiles of Fe3O4@TiO2 core-shell nanoparticles (NPs) were synthetized and characterized, with focus on their antibacterial properties. The NPs consisted of rutile, anatase, magnetite and hema ...

Yves Leterrier

Chat with Graph Search

Internal Stresses and Adhesion of Thin Silicon Oxide Coatings on Poly(ethylene terephthalate)

Alkali-Methanol-Anthraquinone pulping of Miscanthus x giganteus for thermoplastic composite reinforcement

Modeling of multiple cracking and decohesion of a thin film on a polymer substrate

Novel Pulp Fibre Reinforced Thermoplastic Composites

New challenges in solar architectural innovation

Ultra-Light Asymmetric Photovoltaic Sandwich Structures

Evaluation of toughness by finite fracture mechanics from crack onset strain of brittle coatings on polymers

The influence of internal stresses on the microbond test II : Physical aging and adhesion

Life Cycle Assessment of Biofibres Replacing Glass Fibres as Reinforcement in Plastics

Rheological Properties of Hyperbranched Polymer/Poly(ethylene Terephthalate) Reactive Blends

Mechanical integrity of hybrid indium-free electrodes for flexible devices

Stress controlled gas-barrier oxide coatings on semi-crystalline polymers

Effect of inclusions and blending on the mechanical performance of recycled multilayer PP/PET/SiOx Films

Durability of Nanosized Oxygen-Barrier Coatings on Polymers

Conversion and shrinkage analysis of acrylated hyperbranched polymer nanocomposites

Mechanical analysis of ultrathin oxide coatings on polymer substrates in-situ in a scanning electron microscope

UV-nanoimprint lithography and large area roll-to-roll texturization with hyperbranched polymer nanocomposites for light-trapping applications

Surface modified microfibrillated cellulose‐poly(vinylidene fluoride) composites: β‐phase formation, viscoelastic and dielectric performance

Recycling of Bottle Grade PET: Influence of HDPE Contamination on the Microstructure and Mechanical Performance of 3D Printed Parts

Antibacterial surfaces based on functionally graded photocatalytic Fe3O4@TiO2 core-shell nanoparticle/epoxy composites