Characterization of a novel natural cellulosic fiber from Juncus effusus L

TL;DR: The morphology and diameter of the fiber bundles extracted from the stem of the JE plant were characterized by optical and scanning electron microscopy and their thermal degradation behavior was investigated by TGA and their crystallinity was determined using X-ray diffraction technique.

About: This article is published in Carbohydrate Polymers.The article was published on 2017-09-01 and is currently open access. It has received 216 citations till now. The article focuses on the topics: Fiber.

Summary

Introduction

• Environmental concerns and governmental legislations tend to redirect the interest of the scientific community towards the use of materials of natural origin, thus focusing the research topics on recyclable, renewable, and sustainable materials with reduced impact on nature.
• This lignocellulosic fiber is proposed for the first time to be used as potential reinforcement in biocomposite materials.
• For this purpose, morphological and physicochemical characteristics of JE fibers were examined by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and X-ray diffraction (XRD).
• Finally, the results were treated by Weibull statistical analysis with two and three parameters.

Fiber Extraction

• JE plants were collected in Guelma city in the north eastern region of Algeria, during the period of October.
• The roots and marrow parts of JE have been used as medicinal plants in oriental medicine (Park, Won, Hwang & Han, 2014).
• Thermogravimetric analysis (TGA) was performed using a Mettler TG 50 module.
• Experimental results from tests performed on lignocellulosic fibers are difficult to analyze due to the dispersion of the results which are an inherent characteristic of this type of fibers.
• Young's modulus and elongation at break were determined at a 95% confidence level to obtain significant results.

Results and discussion

• Figure 2a displays the SEM image of the cross-section of a JE fiber bundle showing its cell structure which is similar to other lignocellulosic fibers such as fiber bundles from date palm fruit branches (Amroune et al., 2015).
• Figures 5b and 5c show that the mechanical properties of JE fibers are influenced by their diameter.
• This behavior is similar to other lignocellulosic fibers such as technical fibers from date palm fruit branches (Amroune et al., 2015), and sisal (Belaadi et al., 2014).
• The values found for the Young’s modulus (E0) and the strain (Ɛ0) for the two parameters Weibull distribution are equal to 4.80 GPa and 3.43%, respectively, and those for the three parameters Weibull distribution are 5.24 GPa and 2.66%, respectively.

Conclusions

• The following conclusions were drawn from the results of the physicochemical, mechanical and thermal characterization of this new natural fiber.
• The study of the surface morphology by SEM revealed that the cross-section of the JE fiber bundle has a cellular shape similar to other fibers, as reported in the literature for sisal or branch fruit of date palm.
• On the other hand, the longitudinal section of the JE fiber was characterized by the presence of rough surfaces (presence of small voids) which should greatly improve the mechanical anchoring in the manufacture of biocomposites.
• The bands from the FTIR spectrum obtained for JE fiber were analyzed and compared with those reported in the literature for other lignocellulosic fibers.
• The analysis of the tensile tests results showed that the mechanical characteristics estimated by LS-Weibull with 2 parameters are very close to those obtained experimentally compared to LS-Weibull with 3 parameters.

Figures

Figure 1. Photographs of (a) JE plant, (b) stem of JE plant, (c) transverse section of the stem (d) fibers extracted from the stem.

Figure 2. SEM micrographs of (a) the cross-section and (b) longitudinal view of JE fiber. (c) and (d) correspond to a zoom of the cross section and longitudinal view, respectively, of JE fiber.

Figure 4. TGA and DTG curves for JE fiber.

Figure 6. Two and three Weibull distribution for the tensile strength, strain at break, and Young's modulus.

Table 2: Mechanical properties and statistical Weibull parameters for JE fiber and other natural fibers: gauge length (GL), diameter (D), density, strength (s), Young’s modulus (E), and strain at break (e), characteristic strength (σ0), characteristic strain (ε0), characteristic Young’s modulus (E0), andWeibull modulus (mσ, mε, mE).

Figure 3. (a) FTIR spectrum and (b) XRD pattern for JE fiber.

Table 1: FTIR bands observed for JE fiber.

Figure 5. a) Typical stress–strain curve for Juncus effusus L. fiber with magnification of the elastic region, b) and c) diameter dependence of the tensile properties of the JE fiber at GL (40mm). The Young's modulus value found in the present work is substantially equivalent to 4.33 ± 1.4 GPa reported by (Amroune et al., 2015) for technical fibers from date palm fruit branches but remains higher than for other lignocellulosic fibers as reported by (Bezazi et al., 2014) 1.83 ± 0.94 GPa for agave Americana fiber, (Sathishkumar, Navaneethakrishnan, Shankar & Rajasekar, 2013) 3.14 GPa for Spatha fiber, and (Izani, Paridah, Anwar, Nor & H’ng, 2013) 2,763 GPa for oil palm empty fruit bunches fiber. On the other hand, the value of the Young’s modulus reported in this work for the JE fiber bundle is considerably lower than that reported by (Belouadah et al., 2015) 13.2 GPa for Lygeum spartum fiber and (Fiore et al., 2014) 9.4

Frequently asked questions

Q1. What are the contributions in this paper?

In this paper, a new fiber extracted from the stem of the Junusus lignusus Lignus ( J.L.Lignosus ) stem was used to evaluate the properties of the fiber. 

Q2. What are the future works in this paper?

In this article, the properties of a new lignocellulosic fiber extracted from Juncus effusus L. ( JE ) were investigated in order to evaluate the possibility of using it as reinforcement in biocomposite materials. 4 %. - Thermogravimetric analysis of JE fiber evidenced a thermal stability up to 220 °C which confirms the possibility of its use as reinforcement for polymer ( bio or not bio ) matrix composite materials.