This study aims to assess the morphology and properties of fibers extracted from a wild natural plant largely available in Algeria known as Juncus effusus L. (JE). The morphology and diameter of the fiber bundles extracted from the stem of the JE plant were characterized by optical and scanning electron microscopy. The functional groups of the extracted lignocellulosic JE fibers were studied by FTIR, their thermal degradation behavior was investigated by TGA and their crystallinity was determined using X-ray diffraction technique. In addition, mechanical characterization was carried out using tensile tests on the lignocellulosic fiber in order to evaluate their strength, strain at break and Young's modulus. In view of the dispersion in the obtained experimental results, the latter were analyzed using the Weibull statistical laws with two and three parameters.

This study focuses on the chemical and thermo-physical characterization of date palm fiber, which can be used in the reinforcement of green composites. Alkaline solutions with different concentrations of NaOH (0.5, 1, 2 and 3%) and various immersion times (0.5, 1, 2, 4, 6 and 8h) at room temperature were used to treat fibers obtained from date palm fruit branches. In total, 750 samples were tested, and the results obtained show that the chemical treatment of the fibers can lead to an increase, up to 3 times, of their mechanical properties (strength and Young’s modulus) in quasi-static tensile tests. Due to the dispersion in the experimental data, a statistical approach is required to evaluate the mechanical properties. To better understand the phenomena related to the physico-chemical properties of these fibers, several characterization techniques have been used, namely Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction. The data have been compared with results reported in the literature for other lignocellulosic fibers.

In this paper, 400 flax fibers with 10 different lengths (40 fibers at each length) are experimentally characterized (quasi-static tensile behavior) and then the results are statistically analyzed. The quasi-static tensile test results appeared to have a large dispersion, which makes it possible to measure the degree of variability in the ultimate tensile strength (UTS), failure strain, and the Young’s modulus of the fiber, at different gage lengths (10 mm to 500 mm). The variation in mechanical properties at each fiber length is established using two and three Weibull statistics based on maximum likelihood estimation (ML) and least square estimation (LS). Finally, all 10 groups for each tensile property are analyzed by one-way (ANOVA).

The need to preserve nature has led researchers to explore new natural fibers for biodegradable biocomposites. Present work explored first time the thermo-physico-chemical, morphological, and mechanical properties of Yucca treculeana (YT) fiber with a density of 1.330 ± 0.039 g/cm³. The estimated chemical analysis of YT fiber is 82.3%, 12.1%, and 5.6% for cellulose, hemicellulose, and lignin, respectively. The surface chemistry, crystallinity, and functional groups of YT fibers were analyzed by XPS, XRD, and FTIR, respectively. The concentration levels of carbon (62.88%) and oxygen (33.72%) were detected by XPS. XRD analysis showed that the YT fiber has a crystallite size of 3.02 nm and a crystallinity index of 48.85%. Based on the thermal analysis by TGA, the results show thermal stability of the YT fiber up to 360.6°C. The average mechanical properties of the fiber are 222 MPa for the tensile strength, 2.47% for the strain at break and the Young’s modulus is equal to 16.85 GPa. In addition, the results obtained in this study were compared with those found in the related literature. All these results prove that YT fiber can be used as reinforcement in making lightweight industrial biocomposites with thermoplastic or thermosetting polymers.