Hemp Fiber Reinforced Geopolymer Composites: Effects of NaOH Concentration on Fiber Pre-Treatment Process

Abstract:

High demand for using parts of natural materials, e.g., cores, fibers or leaves, as alternative additives are being increased. The main reasons are that natural materials can be served as renewable and eco-friendly choices such a sustainable development. Nevertheless, some limitations of applying those natural products, such as biodegradation, UV degradation, or weak bonding, are raised and need to be modified before further handling. One of the modification techniques for bio-based materials is chemical treatment by using alkaline solution (alkalization). Treatment process allows the plant's fiber to have fewer impurities as well as to increase the bonding on its contacting surface area. This research focuses on (i) effects of NaOH solution concentration on the pre-treatment properties of hemp fibers and (ii) self-treatment behavior of hemp fiber in geopolymer composites. The results show that the concentration of NaOH solution directly affected the pre-treatment process of hemp fiber as higher concentration from 1, 3, 5, 8, 10 to 12 Molar provided more vanishing level of fiber impurities, indicated by Contact Angle (CA) measurement and Fourier Transform Infrared (FT-IR) Spectroscopy analysis. With the concept of alkaline treatment, the self-treatment process was therefore applied for hemp fiber incorporated in alkaline-activated geopolymer matrix. The results illustrate the self-treatment behavior of hemp fiber in geopolymer composites, which could improve the final performances of the hardened products without conventional pre-treatment process.

• Periodical: Key Engineering Materials (Volume 841)
• Pages: 166-170
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.841.166
• Online since: May 2020
• Authors: Phattharachai Maichin, Teewara Suwan*, Peerapong Jitsangiam, Prinya Chindaprasirt
• Keywords: Geopolymer, Hemp Fiber, NaOH Concentration, Natural Fiber, Treatment Process

References

[1] H. Bedlivá, N. Isaacs, Hempcrete–an environmentally friendly material?, Adv. Mater. Res. Trans Tech Publications, 1041 (2014) 83-86.

DOI: 10.4028/www.scientific.net/amr.1041.83

[2] Z. Li, L. Wang, X. J. F. Wang, Compressive and flexural properties of hemp fiber reinforced concrete, Fibers Polym. 5(3) (2004) 187-197.

DOI: 10.1007/bf02902998

[3] L. Y. Mwaikambo, M. P. J. J. o. a. p. s. Ansell, Chemical modification of hemp, sisal, jute, and kapok fibers by alkalization, J. Appl. Polym. Sci. 84(12) (2002) 2222-2234.

DOI: 10.1002/app.10460

[4] J. Cruz, R. J. P. E. Fangueiro, Surface modification of natural fibers: a review, Procedia Eng. 155 (2016) 285-288.

DOI: 10.1016/j.proeng.2016.08.030

[5] R. Vijay, D. L. Singaravelu, A. Vinod, M. Sanjay, S. Siengchin, M. Jawaid, A. Khan, J. J. I. j. o. b. m. Parameswaranpillai, Characterization of raw and alkali treated new natural cellulosic fibers from Tridax procumbens, Int. J. Biologic. macromolecules, 125 (2019) 99-108.

DOI: 10.1016/j.ijbiomac.2018.12.056

[6] A. Shahzad, Hemp fiber and its composites–a review, J. Composite Mater. 46(8) (2012) 973-986.

[7] T. Zhao, L. Jiang, Contact angle measurement of natural materials, Colloids Surfaces B: Biointerfaces, 161 (2018) 324-330.

DOI: 10.1016/j.colsurfb.2017.10.056

[8] D. Dai, M. Fan, Characteristic and performance of elementary hemp fibre, Mater. Sci. Appl. 1(6) (2010) 336-342.