Flax fiber and its composites: An overview of water and moisture absorption impact on their performance

Abstract

Contemporary researchers have specified that natural flax fiber is comparable with synthetic fibers due to its unique physical and mechanical characteristics which have been recognized for decades. Flax fiber reinforced composites have the potential for wide usage in sport and maritime industries, and as automotive accessories. In addition, this composite is in the development stages for future applications in the aeronautical industry. However, designing the flax composite parts is a challenging task due to the great variability in fiber properties. This is caused by many factors, including the plant origin and growth conditions, plant age, location in the stem, fibers extraction method, and the fact that there is often a non-uniform cross-section of the fibers. Furthermore, the water and moisture absorption tendency of the flax fibers and their composites and the consequent detrimental effects on their mechanical performance are also major drawbacks. Fibers may soften and swell with absorbed water molecules, which could affect the performance of this bio-composite. Flax fibers' moisture absorption propensity may lead to a deterioration of the fiber-matrix interface, weakening the interfacial strength and ultimately degrading the quality of the composite. This review represents a brief summary of the main findings of research into flax fiber reinforced composites, focusing on the challenges of its water and moisture absorption behavior on their performance.

Lowering in water absorption capacity and mechanical degradation of sisal/epoxy composite by sodium bicarbonate treatment and PLA coating

“…It was seen that the water immersed samples have lower tensile properties than those of the dry samples owing to the lowering interfacial bonding with development of shear stresses at the interface due to water absorption . The similar results of reduction in tensile properties of the biocomposites by water absorption have been already reported . There were 12.73%, 5.69%, and 3.59% degradation in values of tensile strength, 29.85%, 19.86%, and 14.84% degradation in tensile modulus and 32.61%, 12.56%, and 6.07% degradation in elongation at break due to water absorption for the composites SC, SC (T1), and SC (T2), respectively.…”

Effect of chemical treatment on mechanical properties and water diffusion characteristics of jute‐polypropylene composites

“…The water absorption behavior of NFCs depends on various parameters such as the type of fiber and matrix, the fiber content, its length, manufacturing process, the surrounding temperature, and relative humidity. Few studies have been carried out on jute/PP composites studying the effect of fiber volume fraction on diffusion coefficient and diffusion process in salt water environment . The water diffusion phenomenon in the NFC is commonly modeled using Fick's diffusion law .…”

Comprehensive characterization of a novel natural Bauhinia Vahlii stem fiber

“…[ 19 ] In the beginning phase, the water absorption increases linearly with the square root of time, but after a prolonged time, there is a decline in the trend. [ 30 ] The absorption percentage for untreated fiber is maximum showing the hydrophilic nature of the BV fiber with the presence of all cementitious substances. After treatment, there is a reduction in water absorption due to the removal of hemicellulose, lignin, and wax.…”