Characterization of alkali-activated chrysopogon zizanioides natural fibers as reinforcement for energy-efficient biocomposite applications
Abstract
This study examines the characteristics of alkali-activated Chrysopogon zizanioides natural fibers (CZFs) to determine their applicability as reinforcements in energy-efficient biocomposite applications. Unlike earlier research, which has mostly focused on conventional natural fibers, this paper proposes CZFs as a fresh, sustainable reinforcing possibility. The study investigates the impact of different levels of NaOH (1%, 3%, and 5%) on fiber structure and functionality, offering new insights into optimizing alkali activation for improved interfacial bonding and strength in biocomposites. The results show that alkaline treatment significantly influenced the structural and functional properties of the fibers. X-ray diffraction (XRD) analysis revealed an increase in crystallinity index from 36.17% in untreated fibers to 65.74% in those treated with 5% NaOH, indicating significant removal of amorphous components. FTIR spectra confirmed the reduction of non-cellulosic functional groups, while TGA/DTA analysis demonstrated improved thermal resistance, with a maximum char residue of 4.46% at 600 °C. Mechanical tests showed tensile strength increased from 252 ± 25 MPa to 553 ± 26 MPa and elongation from 4.1% to 5.8%, while SEM analysis revealed cleaner, rougher surfaces that promote fiber–matrix bonding. Additionally, fiber density rose from from 410 ± 20 to 980 ± 20 Kg/m³, and moisture content declined from 8.9% to 5.3%, reflecting improved dimensional stability. Among all treatments, the 5% NaOH-treated fibers offered the most optimal combination of structural, thermal, and interfacial performance. These results indicate that alkali-modified CZFs are promising candidates for use in energy-efficient biocomposites, particularly for lightweight structural components, automotive panels, and sustainable packaging requiring thermal durability and high stiffness.
Keywords
Chrysopogon zizanioides; Alkali treatment; Natural fiber; Thermal stability; Energy-efficient materialsReferences
- [1] M. Alsafran, K. K. Sadasivuni, J. M. Haneesh, M. M. Razavi, and D. M. Kasote, “Extraction and characterization of biofunctional lignocellulosic fibers from Pulicaria undulata plant and the effect of alkali treatment on their bio-physicochemical properties,” Carbohydrate Polymer Technologies and Applications, vol. 8, p. 100542, Dec. 2024, doi: 10.1016/j.carpta.2024.100542.
- [2] J. Tengsuthiwat, V. A, V. R, Y. G. T. G, S. M. Rangappa, and S. Siengchin, “Characterization of novel natural cellulose fiber from Ficus macrocarpa bark for lightweight structural composite application and its effect on chemical treatment,” Heliyon, vol. 10, no. 9, p. e30442, May 2024, doi: 10.1016/j.heliyon.2024.e30442.
- [3] D. Fontanel, “In vitro antimicrobial activity of vetiver root essential oil Chrysopogon zizanioides (L.) Roberty, and relationships with their major chemical compounds. A review,” American Journal of Essential Oils and Natural Products, vol. 13, no. 1, pp. 45–55, Jan. 2025, doi: 10.22271/23219114.2025.v13.i1a.269.
- [4] I. G. C. Barcellos-Silva et al., “Vetiver, Vetiveria zizanioides (L.) Nash: Biotechnology, Biorefineries, and the Production of Volatile Phytochemicals,” Plants, vol. 14, no. 10, p. 1435, May 2025, doi: 10.3390/plants14101435.
- [5] A. Khan et al., “Extraction and characterization of vetiver grass (Chrysopogon zizanioides) and kenaf fiber (Hibiscus cannabinus) as reinforcement materials for epoxy based composite structures,” Journal of Materials Research and Technology, vol. 9, no. 1, pp. 773–778, Jan. 2020, doi: 10.1016/j.jmrt.2019.11.017.
- [6] K. Harini and C. Chandra Mohan, “Isolation and characterization of micro and nanocrystalline cellulose fibers from the walnut shell, corncob and sugarcane bagasse,” International Journal of Biological Macromolecules, vol. 163, pp. 1375–1383, Nov. 2020, doi: 10.1016/j.ijbiomac.2020.07.239.
- [7] T. D. Tavares, J. C. Antunes, F. Ferreira, and H. P. Felgueiras, “Biofunctionalization of Natural Fiber-Reinforced Biocomposites for Biomedical Applications,” Biomolecules, vol. 10, no. 1, p. 148, Jan. 2020, doi: 10.3390/biom10010148.
- [8] A. Vinod et al., “Extraction and Characterization of Natural Fiber from Stem of Cardiospermum Halicababum,” Journal of Natural Fibers, vol. 18, no. 6, pp. 898–908, Jun. 2021, doi: 10.1080/15440478.2019.1669514.
- [9] N. H. Sari et al., “Morphology and mechanical properties of coconut shell powder-filled untreated cornhusk fibre-unsaturated polyester composites,” Polymer, vol. 222, p. 123657, Apr. 2021, doi: 10.1016/j.polymer.2021.123657.
- [10] R. Ilyas et al., “Natural Fiber-Reinforced Polylactic Acid, Polylactic Acid Blends and Their Composites for Advanced Applications,” Polymers, vol. 14, no. 1, p. 202, Jan. 2022, doi: 10.3390/polym14010202.
- [11] F.-E.- Karim, M. R. Islam, R. Ahmed, A. B. Siddique, and H. A. Begum, “Extraction and characterization of a newly developed cellulose enriched sustainable natural fiber from the epidermis of Mikania micrantha,” Heliyon, vol. 9, no. 9, p. e19360, Sep. 2023, doi: 10.1016/j.heliyon.2023.e19360.
- [12] R. Raharjo, D. Bangun Darmadi, F. Gapsari, P. H. Setyarini, and T. D. Widodo, “Characterization of bromelain enzyme treated Bamboo petung fiber (BPF) for composite reinforcement,” Case Studies in Chemical and Environmental Engineering, vol. 9, p. 100683, Jun. 2024, doi: 10.1016/j.cscee.2024.100683.
- [13] N. H. Sari, Suteja, Y. A. Sutaryono, and M. A. Khan, “A Review: Fracture Structure of Natural Fiber after Treatment with Various Alkali Chemicals,” Journal of Fibers and Polymer Composites, vol. 3, no. 2, pp. 158–180, 2024, doi: 10.55043/jfpc.v3i2.203.
- [14] Z. Ren et al., “Effect of Alkali Treatment on Interfacial and Mechanical Properties of Kenaf Fibre Reinforced Epoxy Unidirectional Composites,” Sains Malaysiana, vol. 48, no. 1, pp. 173–181, Jan. 2019, doi: 10.17576/jsm-2019-4801-20.
- [15] N. H. Sari, E. Syafri, Suteja, W. Fatriasari, and A. Karimah, “Comprehensive Characterization Of Novel Cellulose Fiber From Paederia Foetida and Its Modification For Sustainable Composites Application,” Journal of Applied Science and Engineering, vol. 26, no. 10, pp. 1399–1408, 2023, doi: 10.6180/jase.202310_26(10).0005.
- [16] M. Djalal, M. Nafissa, R. Mansour, M. Jawaid, M. Hocine, and B. Lamia, “Effect of alkali treatment on new lignocellulosic fibres from the stem of the Aster squamatus plant,” Journal of Materials Research and Technology, vol. 32, pp. 2882–2890, Sep. 2024, doi: 10.1016/j.jmrt.2024.08.104.
- [17] H. S. Kusuma, D. Permatasari, W. K. Umar, and S. K. Sharma, “Sugarcane bagasse as an environmentally friendly composite material to face the sustainable development era,” Biomass Conversion and Biorefinery, no. January, pp. 1–16, 2023, doi: 10.1007/s13399-023-03764-2.
- [18] S. Sathish et al., “A review of natural fiber composites: Extraction methods, chemical treatments and applications,” in Materials Today: Proceedings, Elsevier Ltd, 2021, pp. 8017–8023. doi: 10.1016/j.matpr.2020.12.1105.
- [19] W. Jin, F. He, S. Song, M. Cao, Y. Zhai, and C. Han, “Study on the mechanical properties of fly ash cement mortar reinforced with alkali-treated sisal fiber and sodium sulfate,” Industrial Crops and Products, vol. 224, no. December 2024, p. 120375, 2025, doi: 10.1016/j.indcrop.2024.120375.
- [20] H. A. Begum, T. R. Tanni, and A. Shahid, “Analysis of Water Absorption of Different Natural Fibers,” Journal of Textile Science and Technology, vol. 7, pp. 152–160, 2021, doi: 10.4236/jtst.2021.74013.
- [21] N. Herlina Sari, I. N. G. Wardana, Y. S. Irawan, and E. Siswanto, “Characterization of the Chemical, Physical, and Mechanical Properties of NaOH-treated Natural Cellulosic Fibers from Corn Husks,” Journal of Natural Fibers, vol. 15, no. 4, pp. 545–558, 2018, doi: 10.1080/15440478.2017.1349707.
- [22] K. Sangeetha and M. Bhuvaneshwari, “Investigation of Physical, Chemical and Structural Characterization of Eichhornia crassipes Fiber,” in International Conference on Information Engineering, Management and Security 2016 (ICIEMS 2016), 1st ed., 2016, ch. Chapter: I, pp. 92–96.
- [23] M. Pokhriyal and P. Kumar, “Mechanical and microstructural behaviour of NaOH treated Himalayacalamus falconeri fibers as biodegradable reinforcing material in polymer based composites Materials Today : Proceedings Mechanical and microstructural behaviour of NaOH treated Himalayacala,” Materials Today: Proceedings, no. April, pp. 1–6, 2022, doi: 10.1016/j.matpr.2022.04.295.
- [24] L. Segal, J. J. Creely, A. E. Martin, and C. M. Conrad, “An Empirical Method for Estimating the Degree of Crystallinity of Native Cellulose Using the X-Ray Diffractometer,” Textile Research Journal, vol. 29, no. 10, pp. 786–794, Oct. 1959, doi: 10.1177/004051755902901003.
- [25] V. Raghunathan et al., “Influence of Chemical Treatment on the Physico-mechanical Characteristics of Natural Fibers Extracted from the Barks of Vachellia Farnesiana,” Journal of Natural Fibers, vol. 00, no. 00, pp. 1–11, 2021, doi: 10.1080/15440478.2021.1875353.
- [26] I. Dembri, A. Belaadi, A. Lekrine, M. Jawaid, A. S. Ismail, and D. Ghernaout, “Effect of alkaline treatment on the thermo-physicochemical and mechanical properties of biochar powder/Washingtonia robusta fibers/PLA hybrid biocomposites,” Journal of Materials Research and Technology, vol. 33, no. December, pp. 9735–9751, 2024, doi: 10.1016/j.jmrt.2024.12.018.
- [27] F. A. Rezeikinta, A. Kasim, E. Syafri, I. Chaniago, and F. Ridwan, “Reducing Water Absorption and Increasing the Density of Kapok (Ceiba pentandra, L.) Fibers from Kapok Production Center in Indonesia,” International Journal of Design and Nature and Ecodynamics, vol. 18, no. 1, pp. 195–200, 2023, doi: 10.18280/ijdne.180124.
- [28] R. G. Elenga, G. F. Dirras, J. Goma Maniongui, P. Djemia, and M. P. Biget, “On the microstructure and physical properties of untreated raffia textilis fiber,” Composites Part A: Applied Science and Manufacturing, vol. 40, no. 4, pp. 418–422, 2009, doi: 10.1016/j.compositesa.2009.01.001.
- [29] R. Thandavamoorthy, Y. Devarajan, and S. Thanappan, “Analysis of the characterization of NaOH-treated natural cellulose fibre extracted from banyan aerial roots,” Scientific Reports, vol. 13, no. 1, pp. 1–8, 2023, doi: 10.1038/s41598-023-39229-9.
- [30] H. J. Rao, S. Singh, and P. Janaki Ramulu, “Characterization of a Careya Arborea Bast Fiber as Potential Reinforcement for Light Weight Polymer Biodegradable Composites,” Journal of Natural Fibers, vol. 20, no. 1, pp. 71–87, 2023, doi: 10.1080/15440478.2022.2128147.
- [31] M. Pokhriyal, P. K. Rakesh, S. M. Rangappa, and S. Siengchin, “Effect of alkali treatment on novel natural fiber extracted from Himalayacalamus falconeri culms for polymer composite applications,” Biomass Conversion and Biorefinery, vol. 14, no. 16, pp. 18481–18497, 2024, doi: 10.1007/s13399-023-03843-4.
- [32] A. Amior, H. Satha, F. Laoutid, A. Toncheva, and P. Dubois, “Natural Cellulose from Ziziphus jujuba Fibers: Extraction and Characterization,” Materials, vol. 16, no. 1, 2023, doi: 10.3390/ma16010385.
- [33] X. Luo and X. Wang, “Preparation and characterization of nanocellulose fibers from NaOH/urea pretreatment of oil palm fibers,” BioResources, vol. 12, no. 3, pp. 5826–5837, 2017, doi: 10.15376/biores.12.3.5826-5837.
- [34] Jamasri and F. Yudhanto, “The Effect of Alkali Treatment and Addition of Microcrystalline Cellulose (MCC) on Physical and Tensile Properties of Ramie/Polyester Laminated Composites,” Revue des Composites et des Materiaux Avances, vol. 32, no. 2, pp. 77–84, 2022, doi: 10.18280/rcma.320204.
- [35] K. Büyükkaya, “Examining the Physical and Thermal Properties of Nettle Fibers Obtained from Different Genetic Sources and Determining Their Usability as Reinforcement Materials in Composites,” Journal of Natural Fibers, vol. 22, no. 1, pp. 1–24, Dec. 2025, doi: 10.1080/15440478.2025.2519609.
- [36] Y. Subagyo et al., “Development of magnesium biocomposites with hydroxyapatite or carbonate apatite reinforcement as implant candidates: A review,” Mechanical Engineering for Society and Industry, vol. 3, no. 3, pp. 152–165, 2023, doi: 10.31603/mesi.10389.
- [37] M. A. Rahman, M. Ndiaye, B. Weclawski, and P. Farrell, “Alkali-treated Borassus Husk Fibre Reinforced High-heat Resistant Epoxy Composites: Insights into Their Thermal, Dynamic Mechanical and Outgassing Properties,” Apr. 21, 2025. doi: 10.22541/au.174526773.38930625/v1.
- [38] J. Hindi, M. K, K. S. Bhat, G. B M, A. Ibrahim, and S. Y M, “Physical, Morphological, Tensile, and Thermal Stability Characteristics of Novel Tinospora Cordifolia Natural Fiber,” Journal of Natural Fibers, vol. 22, no. 1, pp. 1–12, 2025, doi: 10.1080/15440478.2024.2437539.
- [39] I. G. N. N. Santhiarsa, I. G. B. W. Kusuma, I. P. Lokantara, N. M. Dwidiani, S. P. G. G. Tista, and I. G. A. Negara, “The influence of NaOH concentration on the mechanical properties of Corypha gebanga fiber-reinforced composites,” Archive of Mechanical Engineering, vol. 71, no. 4, 2024, doi: 10.24425/ame.2024.152616.
- [40] J. R. H et al., “Effect of chemical treatment on physio-mechanical properties of lignocellulose natural fiber extracted from the bark of careya arborea tree,” Heliyon, vol. 10, no. 5, p. e26706, Mar. 2024, doi: 10.1016/j.heliyon.2024.e26706.
- [41] P. Sathiamurthi, K. S. Karthi Vinith, T. P. Sathishkumar, S. Arunkumar, and A. S. Anaamalaai, “Fiber extraction and mechanical properties of Agave Americana/Kenaf fiber reinforced hybrid epoxy composite,” Materials Today: Proceedings, vol. 46, pp. 8594–8601, 2021, doi: 10.1016/j.matpr.2021.03.571.