Antoine Le Duigou

• Professor
• Professor (Full) at University of Southern Brittany

Recently, interest has been increasing in natural fibres as composite reinforcing fillers for polymer-based filaments manufactured with the Fused Deposition Modeling (FDM) process, despite their moderate mechanical properties compared to pure polymer.An innovative way was proposed in the present work to optimize the mechanical properties of biocomp...

Hygromorph composites are moisture-induced shape changing materials that are increasingly studied to develop autonomously actuated deployable structures. The morphing mechanism is based on the high affinity for moisture and the hygro-expansive nature of at least one component, combined with a bilayer microstructure. Among available hygromorphs thos...

The additive manufacturing of structural composites is a disruptive technology currently limited by its moderate mechanical properties. Continuous fibre reinforcements have recently been developed to create high performance composites and open up encouraging prospects. However, to increase their use, deeper understanding of the relationship between...

Hygromorph biocomposites (HBC) possess moisture-induced actuation from bioinspired designs. The present work describes a large experimental and comprehensive database of the hygro-mechanical and bending actuation properties of flax/maleic anhydride grafted polypropylene (MAPP) HBC composites over a large range of moisture variation (10-90% RH) and...

Hygromorph biocomposite (HBC) actuators make use of the transport properties of plant fibres to generate an out-of-plane displacement when a moisture gradient is present. HBC actuators possess a design based on the bilayer configuration of natural hygromorph actuators (like Pine cone, Wheat awn, Selaginella lepidophyll). In this work we present a s...

Environmental regulations are forcing certain industrial sectors to quantify their environmental impact, using environmental analysis tools. Currently, there is a lack of appropriation of these tools in industrial sectors. Participative approaches are relevant to tackle this issue. This article proposes an approach for co-creating an environmental...

Biological structures provide inspiration for developing advanced materials from sustainable resources, enabling passive structural morphing. Despite an increasing interest for parsimony‐oriented innovation, sustainable shape‐changing materials based on renewable resources remain underexplored. In this work, the architecture of a single plant fiber...

Le chapitre décrit l’influence des facteurs intrinsèques (relatifs au polymère) et extrinsèques (liés au milieu) sur la dégradation des polyesters susceptible de se manifester aux différentes échelles (macroscopique, microscopique et moléculaire). Il se focalise essentiellement sur deux types de polyesters : les polyhydroxyalcanoates (PHA) et les p...

Biological structures combine passive shape‐changing with force generation through intricate composite architectures. Natural fibers, with their tubular‐like structures and responsive components, have inspired the design of pneumatic tubular soft composite actuators. However, no development of passive structural actuation is available despite the r...

The competitive sailing boat industry uses carbon fibre for high-performance purposes. Nevertheless, this material is known to cause environmental issues during its manufacturing. We can currently observe, based on the literature, difficulty integrating a reliable, justified, and transparent inventory of carbon-fibre production for LCA applications...

Artificial reefs represent useful tools to revitalize coastal and ocean ecosystems. Their formulation determines the biofilm formation which is the prerequisite for the colonization process by marine micro- and macroorganisms. In comparison with concrete, biobased polymers offer improved characteristics, including architecture, formulation, rugosit...

This work reported a novel two-stage in-situ impregnation method for additively manufacturing dry fiber bundles reinforced polymer composites using a commercial dual-nozzle 3D printer. This process allowed simultaneous manufacturing of both continuous fiber prepreg filaments and continuous fiber reinforced polymer composites (CFRPCs). Initially, it...

Hygromorph BioComposites (HBC) exhibit shape-changing actuated by a moisture content (MC) variation due to their bilayered bioinspired architecture. However, their application in daily meteorologic variation is limited due to relative humidity (RH) and thermal couplings. This work aims to investigate the role of temperature variation on the shape c...

Purpose Recent decades have seen the emergence of environmental problems such as global warming, partly caused by maritime transport. To tackle environmental problems, the shipping industry has introduced regulations, and, in response, environmental analyses have been carried out. Studies have suggested the use of life cycle assessment (LCA) in the...

The application of continuous natural fibers as reinforcement in composite thin-walled structures offers a feasible approach to achieve light weight and high strength while remaining environmentally friendly. In addition, additive manufacturing technology provides a favorable process foundation for its realization. In this study, the printability a...

With the growing prominence of environmental conservation awareness, there has been a notable surge in the exploration of renewable materials, particularly in the realm of natural fiber reinforced polymer composites. This heightened focus is underscored by the recent advancements in additive manufacturing techniques dedicated to continuous natural...

This study focused on exploring the behavior of 3D-printed thermochromic PLA structures under varying temperature and frequency using DMA. The specimens tested were produced using the fused deposition modeling (FDM) technique. The present work aims to determine the temperature range that yields optimal performance of 3D-printed thermochromic PLA st...

Hydromorph Biocomposites (HBCs) are self‐shaping materials whose motions are actuated by moisture‐induced swelling of natural fibers and designed through a multilayered bioinspired material architecture. Their reactivity, i.e., kinetic of actuation, is relatively slow and is currently limited by the moisture transport. Porosities are commonly assum...

Four-dimensional (4D) printing involves the creation of materials that can change their shape, structure, or functionality over time in response to external stimuli. This incredible adaptability opens new possibilities in fields ranging from robotics to biomedical applications. This focus issue in Smart Materials and Structures is dedicated to the...

The 3D printing of continuous carbon fiber-reinforced thermoplastics (c-CFRTP) results in fiber waviness and voids that limit mechanical performance. The effects of tensioning and compaction forces during 3D printing were experimentally studied to suppress fiber waviness. A tensioning force was generated along the filament to straighten the fibers...

In recent years, innovations in 3D/4D printing techniques for continuous fiber-reinforced polymer composites (CFRPCs) have opened new perspectives for the integrated design and manufacture of composites with customized functions. This paper reviews the current state of 3D/4D printed functional composites, including the materials, shape memory/chang...

Current applications of mass diffusion in composite structures with natural fibres reinforcements focus on the development of large thickness, balanced laminates, and long diffusion times. Hygromorph composites are, however, thin in thickness and possess slender shapes with unbalanced laminate designs, together with higher moisture diffusion speeds...

First of all, this article aimed to evidence the role of a modified printer developed for continuous carbon fibre reinforced PolyAmide (cCF/PA6-I) together with the use of a fully open slicing step on the printing quality and the longitudinal/transverse tensile and in-plane shear properties. A comprehensive assessment of the microstructure and prop...

The microdroplet test is commonly used to determine the apparent interfacial shear strength (IFSS) of fibre-reinforced microcomposites. A deeper analysis of the test outcome can provide meaningful information about the fibre / matrix interface behaviour if a predictive approach is adopted. In this study, this predictive approach was used to investi...

Recent advances in additive manufacturing (AM) techniques, particularly three-dimensional (3D) printing and four-dimensional (4D) printing have enabled the production of different parts of robots, including sensors and actuators, with high multifunctionality, compliance, and manufacturing flexibility unlike in traditional approaches (Bodaghi and Zo...

In recent years, 4D printing has allowed the rapid development of new concepts of multifunctional/adaptive structures. The 4D printing technology makes it possible to generate new shapes and/or property-changing capabilities by combining smart materials, multiphysics stimuli and additive manufacturing. Hygromorphs constitute a specific class of new...

This work reported a novel dual-nozzle 3D printing method for continuous fiber reinforced composite cellular structures (CFRSs). The dual-nozzle modules and corresponded printing paths were proposed to realize the CFRSs by theoretically increasing two times manufacturing speed. Based on this novel dual-nozzle 3D printing method, typical rhombus fil...

The work describes the exploration of the design space by fabrication, modelling and testing of bio-based and humidity-triggered 4D printed shape-changing biocomposites. The aim is to broaden the understanding of the control actuation via printing path tailoring and unlock new potential applications for biomaterials and autonomous actuator design....

The present work aimed to study the quasi-static compression behaviors of 3D printed continuous ramie fiber reinforced biocomposite corrugated structures (CFCSs) with excellent shape memory effects. The in-plane compression test was conducted to evaluate the effects of cell shapes, fiber volume fraction (f v) and addition of fiber on the compressio...

Continuous fiber reinforced composite lightweight structures (CFRSs) are widely applied to aerospace, automobile, marine and other fields due to their high specific strength and modulus, low density and fatigue resistance. Innovations in the additive manufacturing technique of continuous fiber reinforced composites (CFRC) opened new perspectives fo...

The present work aimed to study the penetration behaviors of 3D printed continuous ramie yarn reinforced polylactic acid (PLA) based woven-like and non-woven-like biocomposites. The architectures were produced by in-situ impregnated 3D printing process according to a novel interweaved and a conventional printing path (unidirectional and orthogonal)...

This paper describes a novel voxel-based technique to accurately model 3D printed continuous yarns of fibre composites at printed filament scale. To cater for the constraints of continuous filament printing, the design strategy here makes use of a set of variables that fully define the printing path as input in the model. A voxel-based algorithm is...

Electroadhesion has shown potential to deliver versatile handling devices because of its simplicity of actuation and rapid response. Current electroadhesion systems have however significant difficulties in adapting to external objects with complex shapes. Here, a novel concept of metasurface is proposed combining the use of natural fibres (flax) an...

3D-printing of biocomposites using continuous natural fiber composites is emerging as a relevant manufacturing method to develop highly tailorable materials. These are materials with high performance characteristics, whose capabilities have been achieved through the controlled design of the mesostructure via the 3D printing process. However, the de...

This data article presents four experiment results related to flax fibre composites with epoxy shape memory polymer matrix: water vapor absorption, mass diffusion immersed in water, hygroscopic expansion, mechanical properties. The water vapor absorption tests are described by raw data related to four types of laminates with weights measured at dif...

This article investigates the development and the evolution of hygroscopic stresses within flax/ Polypropylene + Maleic Anhydride grafted Polypropylene (PP+MAPP) asymmetric biocomposites when exposed to various hygroscopic cycles that simulate a wide range of outdoor applications with large Relative Humidity (RH) variation (from 11 to 50% RH, 50-99...

Humidity responsive materials are increasingly attracting significant interest for soft robotics and deployable structures. Their shape-changing behavior is based on differential hygroscopic characteristics of the single components of their microscopic architecture. Although existing moisture-induced materials achieve morphing in various humidity c...

The swelling of natural fibers is often a drawback when considering structural applications of biocomposites. However, this mechanism represents the key towards the development of Hygromorph BioComposites (HBC). This investigation aims to understand the hydroexpansion of 3D-printed continuous flax-fiber reinforced biocomposites and the effect of ma...

The paper describes the influence provided by the humidity on the mechanical and failure properties of 3D printed composites made by continuous flax fibres reinforcing a poly-lactic acid matrix. The bulk in-plane shear, transverse and longitudinal samples considered here have 28-31% fibre volume fraction and 3-6% porosity. The longitudinal and tran...

Natural fibers are moisture-sensitive due to their complex polysaccharidic composition. Upon moisture intake, they exhibit large hygroexpansion, which is controlled by their multiscale architecture. Composite materials using natural fibers are therefore affected by humidity, which limits their application. The most common approach found in the lite...

4D printing focus on the integration of a targeted morphing function by controlling the properties and the architecture of the materials. The present work evaluates the potential of tailoring 4D printing to Hygromorph BioComposite (HBC), which paves the way for the construction of a new generation of sustainable shape-changing metamaterials with a...

This article presents an alternative manufacturing process for unidirectional tape natural fiber Polypropylene with Maleic Anhydride grafted PolyPropylene (PP + MAPP) thermoplastic composites that could enable large high performance parts to be built, while being recyclable at end of life. The performance target is flax/epoxy composites that are cu...

Cellular materials with tailorable properties are increasingly being used as a controllable morphing mechanism in airfoils. Nonetheless, the flexural properties of this mechanism change depending on the configuration. Thus, the aim of this paper is to identify and analyse parameters tailoring these properties. A multi-scale analysis that models rel...

Le littoral et la mer sont des ressources naturelles environnementales. C’est-à-dire des ressources qui, sans être un produit de l’activité humaine, influent ou pourraient influer sur l’économie des pays ou le bien-être de leurs habitants. Partout dans le monde, ces zones concentrent des populations croissantes et des activités multiples. Les impac...

Retting of fibrous plants such as flax is an essential step in the extraction of fibre bundles and their transformation into textiles and reinforcement fabrics for use in garments and composites. Dew-retting is traditionally performed from Northwest France to the Netherlands, as the climate is highly favourable for this process. Hemp is a plant tha...

3D printing represents a great opportunity for biocomposites to be developed for the first time on the same time scale as their synthetic counterparts. The purpose of this article is a global investigation of the relationship between slicing parameters (i.e. Layer Height (LH), Interfilament Distance (ID), Number of Trips (NT), Number of Layers (NL)...

The paper describes an optimised strategy to measure the porosity in natural fibre composites. Particular emphasis is placed on thermoformed flax fibres reinforced poly-lactic acid (FFRPLA) laminates. Six different methods to measure the porosity were evaluated and compared: gravito-metry in ethanol and in water, scanning electron microscopy (SEM),...

The aim of this study is to investigate the dimensional variation of polypropylene composites reinforced with UD flax fibers, and the modification of its dynamical mechanical properties after moisture absorption. The effects of fiber content, coupling agent and moisture content were also examined. Results have shown that the swelling increases sign...

Fibre orientation is an essential factor governing the mechanical properties of composite materials. This study proposes an original method based on gray-level granulometry to analyse the fibre orientation distribution (FOD) of synthetic and natural fibre reinforcements aiming composite applications. An orientation maps is computed from SEM images...

To date, the literature has focused on synthetic fibre-reinforced composites, but it has not adequately addressed the unique properties that differentiate natural from synthetic fibres, such as their natural variation in microstructure and composition across species. This review paper proposes a critical overview of the current state of 3D printing...

This study reports a three-dimensional compaction printing (3DCP) technique for a continuous carbon fiber reinforced thermoplastic (CFRTP). A hot-compaction roller was equipped with a fused filament fabrication (FFF)-based 3D printer to press the filament against the printer bed immediately after the printing to reduce voids and improve adhesion be...

Hygroscopicity of natural fibers influences biocomposites lifetime submitted to wet environments. The present study investigates the hygroscopic stresses state in a flax fiber reinforced polypropylene composite when submitted to different environmental conditions from the dried state through various relative humiditiy (RH) to immersion. An experime...

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 availab...

Ce travail a pour objectif d’étudier l'évolution des propriétés hygromécaniques des composites non-tissés lin/PP dans une large gamme d'humidité relative allant de 10 à 98% RH. L'influence de la microstructure sur le comportement hygroscopique et mécanique est étudiée avec des taux de porosité variables (Φ = 5, 30, 50%). La porosité a un impact imp...

Le but de la présente étude est de prouver l'effet d'une modification d'énergie de surface de fibres de lin par traitement thermique sur le comportement mécanique de composites bio-sourcés. Il a été montré que ce traitement améliore le mouillage des fibres par de la résine époxy en réduisant le taux de porosité dans le composite. Des tests visant à...

Ce travail a pour objectif d'étudier l'évolution des propriétés hygromécaniques des composites non-tissés lin/PP dans une large gamme d'humidité relative allant de 10 à 98% RH. L'influence de la microstructure sur le comportement hygroscopique et mécanique est étudiée avec des taux de porosité variables (Φ = 5, 30, 50%). La porosité a un impact imp...

This work aims to understand the thermo-hygro-mechanical properties of flax nonwoven polypropylene (PP) composites by decoupling moisture and temperature effects. Composites were stored over a wide range of relative humidity (10, 33, 50, 75 and 98% RH) at a constant temperature of 23°C until saturation before moisture content (MC), dimensional vari...

The hygro-mechanical behavior of single hemp fiber/epoxy interface was investigated through its characterization at the microscopic scale. Microdroplet debonding tests were developed in controlled humidity chambers to study the interfacial properties and adhesion mechanism of hemp/epoxy systems in in-use environmental conditions (from 9% to 98% rel...

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 ce...

This article provides deeper insight into moisture sorption over a wide range of relative humidity (RH), from 9% to 98%, and its effect on the evolution of the tensile behaviour and performance of hemp/epoxy unidirectional biocomposites. Moisture sorption is associated with orthotropic hygroscopic expansion which is also related to the influence of...

The control of hemp plant harvesting, in particular the retting process, represents the major step for the development of high-performance hemp biocomposites. In this study, the consequences of hemp retting on the ease of fibre extraction and tensile properties of elementary hemp fibres is explored. Stem peeling experiments are combined with scanni...

The aim of this work was to study the effect of free surface energy modification of flax fibres by a thermal treatment on the mechanical behaviour of bio-based composites. It has been proved that this modification enhances the wettability of flax fibres by liquid epoxy resin and results in a lower porosity amount in composites. Tests to evaluate me...

The hygro-mechanical behaviour of a bio-sourced composite material (MAPP/flax) is experimentally investigated through the characterization of its moisture diffusion and elastic properties, as well as the in-plane hygroscopic swelling of a unidirectional ply sequence and curvature in the case of an asymmetric lay-up sequence. From these consideratio...

Despite the wide development of biocomposites, their compressive behaviour is still not well understood. In this paper, the longitudinal compressive and tensile behaviour of unidirectional natural fibres is studied through a parametric analysis taking into account the nature of the fibre (flax or jute), the matrix (thermoplastic and thermoset: PP,...

Biocomposites reinforced with hemp fibres present a high potential for valorisation in new industrial applications due to their intrinsic mechanical characteristics. To reach certain markets, it is unavoidable to validate their behaviour and durability in humid and water environments. This article aims to provide a better insight into the effect of...

PeakForce Quantitative Nano-Mechanical property mapping (PF-QNM) was applied to explore the nano-mechanical properties of the cell wall of two kinds of flax fibre preparation: isolated and within a poly-(butylene succinate) (PBS) or maleic anhydride grafted poly-(propylene) (PP-MAPP) matrix in unidirectional flax (UD) composites. Isolated flax fibr...

Natural fibre composites are increasingly used in the composite industry due to their good stiffness-to-weight ratio and their low environmental footprint. However, their use can be limited by their moisture sensitivity. Rather than applying conventional engineering strategies (chemical/physical treatments), Université of Bretagne Sud (UBS)-IRDL (L...

National conference dedicated to degradation of biocomposites along their lifecycle. The scope includes academics and industrials working in Building, marine, transports fields

The purpose of this article is to understand the influence of typical composite parameters (interfacial bond strength, surface-area and fibre mechanical properties) on the tensile properties of nonwoven composite materials. The materials investigated were flax, hemp and Poly-(propylene) (PP) and Maleic Anhydride-grafted PP (MAPP), which provide dif...

Hemp (Cannabis Sativa) and flax (Linum Usitatissimum L) are the most commonly cultivated fibre plants in Europe. The use of their fibres covers a wide range of applications and requires a precise knowledge of their mechanical properties. The aim of this study is to investigate the contribution of fibres to the stiffness of flax and hemp dry stems s...

Hygromorph biocomposite (HBC) actuators make use of the transport properties of plant fibres to generate an out-of-plane displacement when a moisture gradient is present. HBC actuators possess a design based on the bilayer configuration of natural hygromorph actuators (like pine cone, wheat awn, Selaginella lepidophyll). In this work we present a s...

The goal of this work is to demonstrate the advantages of nano-mechanical characterisations using an Atomic Force Microscope (AFM) for measuring (visco)elastic properties fields within the different cell wall layers of vegetal fibres (e.g., flax, wood). This tool particularly allows for measuring "in situ" properties at the submicrometre scales and...

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, attribut...

Les fibres végétales présentent un comportement hydrophile marqué conduisant à une absorption d'eau associée à un gonflement important, en milieu humide. Ce gonflement hygroscopique, lié à la microstructure des fibres, est élevé en comparaison de systèmes synthétiques (verre, carbone). Ainsi, à l'échelle d'un stratifié, la variation d'humidité cond...

Hygromorph biocomposites (HBCs) are hygroscopically active materials with moprhing ability upon a moisture variation. They turned the water sensitivity of natural fibres into the driving force of the HBC actuation. A novel asymmetric 0/90 • microstructure, where both passive and active layers have included flax fibres, has been used. Faster actuati...

During the past few years, environmental concerns have drastically increased the technical requirements for automotive parts. Composite materials are becoming more and more popular because they provide solutions that help decrease CO2 emissions by reducing parts weight.

Peak-Force Quantitative Nano-Mechanical property mapping (PF-QNM) was applied to explore the nano-mechanical properties of flax fibre cell walls in cross-section. After validation of the ability of PF-QNM to determine stiffness gradients in aramid fibres, measurements were performed on developing flax bast fibres. The presence of two layers with di...

Straw bales are seen as increasingly viable for building insulation and even for the construction of small load-bearing straw houses in the last decades, especially in view of the need to seek low environmental footprints. Straw bales can be used as load-bearing structures but they are currently mainly used as a filler insulation material associate...

In this study, we explore the interest of recycling PA11 and PP unidirectional flax fibre composites. After describing the mechanical performance of the various components of the composite, its tensile properties are investigated before and after recycling. The results indicate a good stability of the modulus and strength of the composites during t...

Natural fibers nonwovens are widely used in the automotive industry because of their interesting mechanical performances combined with good acoustical properties. This double function can be achieved by the creation of a controlled volume of porosities in the material. This paper studies the impact of porosity content on acoustic (normal incidence...