Mechanical Properties of Flax and Hemp Yarns Designed for the Manufacturing of Geotextiles. Improvement of the Resistance to Soil born Microorganisms

Abstract

Geotextiles are widely used to stabilize river banks from erosion when these ones are restored into vegetal covered areas as mentioned by European regulations. For these applications imported coir (coconut shell fibres) based geotextiles are generally used because coir fibres show a good resistance to soil degradation. In Europe, flax and hemp plants are already grown for textile, building or oil applications. By-products of these industries such as flax tows and short hemp fibres were used to manufacture yarns. The resistance to degradation via the measurement of the mechanical properties of these yarns submitted to enzymatic (cellulase) and microbial attacks (Cellvibrio gandavensis) mimicking soil degradation was evaluated. Large decreases in mechanical properties were observed, even though these ones were still higher than the as received reference coir material. After impregnation by chitosan of the fibres, the tensile properties of the yarns globally remained unchanged after severe attacks. The chitosan acts as a protection against the soil microorganism attacks. As a consequence, flax and hemp by-products could be good candidates for local manufacturing of biodegradable geotextiles.

Development of 100% Linseed Flax Yarns with Improved Mechanical Properties and Durability for Geotextiles Applications

“…So, fewer fibres enabled better strength results when using the linseed flax fibres to produce yarn for geotextile applications. The linseed flax yarn's tensile strength and linear mass value were in the same order of magnitude as those of the hemp yarn in Ouagne et al [21]. The yarn in this study will thus undoubtedly be usable for subsequent geotextile applications.…”

“…As compared with previous results in the literature, the tensile strength of the optimal yarn showed a real interest of the linseed flax fibres for yarn manufacturing for geotextile applications. In Ouagne et al [21], hemp and coir yarns used for geotextile applications had a tensile strength of 45 MPa and 14 MPa, respectively, for linear mass values of 4312 tex and 6172 tex, respectively. The results of the optimal linseed flax yarn are much higher than those of the coir yarn (+250% for tensile strength), which is already used in geotextile applications.…”

“…In parallel, some treatments applied to fibres prior to their use in geotextiles could increase their life in the soil by inhibiting the activity of cellulolytic soil bacteria and/or by increasing their hydrophobic character. Low-molecular-weight chitosan is able to protect textile flaxfibre-based yarns against natural soil biodegradation when impregnated on the fibres, preventing the degradation of amorphous and crystalline cellulose, hemicelluloses and pectins [20,21]. As a reminder, chitosan is a polyoside produced from chitin, the component of the exoskeleton of crustaceans.…”

Comparison of Mechanical and End-Use Properties of Grey and Dyed Cellulose and Cellulose/Protein Woven Fabrics

“…Tensile, impact and flexural properties of the created composites were established. The structure of manufactured textile composites was also investigated by scanning electron microscopy [ 30 ].…”