Physico-mechanical performances of flax fiber biobased composites: Retting and process effects - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Industrial Crops and Products Année : 2021

Physico-mechanical performances of flax fiber biobased composites: Retting and process effects

Résumé

This research aimed to evaluate the effect of retting (3 levels were concerned) and processing parameters (mainly temperature) on physico-chemical properties of flax-epoxy materials. 9 biobased composites were produced with 3 different processing programs: Setup 1, 2, and 3. An advanced organoleptic study has been carried out on both technical flax fibers and manufactured composites to study in more detail the effects of the processing and retting on the visual aspect. Organoleptic analysis shows that flax, as well as biobased composites, lose saturation and luminance by increasing retting time. Increasing the processing temperature alters the material color. According to SEM analysis, we highlight that the least retted fibers are presented in bundles that are well bonded and coated with each other to form a technical fiber. Depending on retting, technical fibers appear cleaner and more individualized but their mechanical properties are affected. An interesting approach has been applied for the determination of the volumic content of our biobased composites, using both TGA and pycnometer methods. On average, V f decreases from 63.1 % for early retting (−) to 51.5 % for late retting (+). This effect could naturally result from the observed individualization of the fibers. Moreover, the porosity rates V p increase overall with fiber content. On average it varies from 5 to 11 % in function of retting. Setup 3, with a processing temperature of 160 • C, a processing time of 130 min and a processing pressure of 50 bars, is the most desirable because it allows the highest V f for the lowest V p. Regarding the mechanical behavior of biobased composites, we have observed a non-elastic behavior of our stress-strain curves, due to the intrinsic behavior of flax fibers. Stress vs strain curves reveal 3 different areas for elastic and plastic transitions. It also appears that setup 3 provides the best modulus of elasticity compared to the other setups. We notice also that E1 Young's modulus gradually increases with retting. By performing a normalization of E1 modulus according to the fiber volume, the effect of retting is even more pronounced. A 40 % increase in modulus can be observed between retting (−) and (+). At the end, the long retting level of technical flax fibers, as well as the third setup gives the best compromise for our bio based composite performances.
Fichier principal
Vignette du fichier
S092666902100875X.pdf (1.65 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03396747 , version 1 (16-10-2023)

Licence

Paternité - Pas d'utilisation commerciale

Identifiants

Citer

Morgan Lecoublet, Mehdi Khennache, Nathalie Leblanc, Mohamed Ragoubi, Christophe Poilâne. Physico-mechanical performances of flax fiber biobased composites: Retting and process effects. Industrial Crops and Products, 2021, 173, ⟨10.1016/j.indcrop.2021.114110⟩. ⟨hal-03396747⟩
59 Consultations
12 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More