In order to replace conventional materials in the existing composite world, there has been a focus on adopting coir fibres, which are lightweight, adaptable, efficient, and have great mechanical qualities. This study describes the creation of environmentally responsible bio-composites with good mechanical characteristics that employ coir powder as a reinforcement, which has good interfacial integrity with an epoxy matrix. And these epoxy-coir composites supplemented with coir particles are predicted to function as a reliable substitute for traditional materials used in industrial applications. Here, untreated and alkali-treated coir fibres powder were employed as reinforcement, with epoxy resin serving as a matrix. An experimental investigation has been carried out to study the effect of coir powder reinforcement at different weight percentages (5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, and 30 wt%). The morphological study, followed by a scanning electron microscope (SEM) and an optical microscope (OM), demonstrated that the powder and matrix had the strongest adhesion at 20 wt% coir powder-reinforced composite, with no voids, bubbles, or cracks. Based on the entire investigation, the polymer composite with 20 wt% reinforcement exhibited better mechanical qualities than the other combinations.

1. Kangishwar S, Radhika N, Sheik AA, et al. A comprehensive review on polymer matrix composites: material selection, fabrication, and application. Polymer Bulletin. 2022; 80(1): 47–87. doi: 10.1007/s00289-022-04087-4

2. Rajak D, Pagar D, Menezes P, et al. Fiber-Reinforced Polymer Composites: Manufacturing, Properties, and Applications. Polymers. 2019; 11(10): 1667. doi: 10.3390/polym11101667

3. Al-Azad N, Asril MFM, Shah MKM. A Review on Development of Natural Fibre Composites for Construction Applications. Journal of Materials Science and Chemical Engineering. 2021; 09(07): 1–9. doi: 10.4236/msce.2021.97001

4. Lau K tak, Hung P yan, Zhu MH, et al. Properties of natural fibre composites for structural engineering applications. Composites Part B: Engineering. 2018; 136: 222–233. doi: 10.1016/j.compositesb.2017.10.038

5. Pulikkalparambil H, Varghese SA, Chonhenchob V, et al. Recent Advances in Natural Fibre-Based Materials for Food Packaging Applications. Polymers. 2023; 15(6): 1393. doi: 10.3390/polym15061393

6. Majeed K, Jawaid M, Hassan A, et al. Potential materials for food packaging from nanoclay/natural fibres filled hybrid composites. Materials & Design (1980–2015). 2013; 46: 391–410. doi: 10.1016/j.matdes.2012.10.044

7. Ali HT, Alghtani AH, Felemban BF, et al. Multivariable analysis for selection of natural fibers as fillers for a sustainable food packaging industry. Materials Research Express. 2021; 8(9): 095504. doi: 10.1088/2053-1591/ac17a9

8. Naik V, Kumar M, Kaup V. A Review on Natural Fiber Composite Material in Automotive Applications. Engineered Science. 2022; 18: 1–10. doi: 10.30919/es8d589

9. Huda MS, Drzal LT, Ray D, et al. Natural-fibre composites in the automotive sector. In: Pickering KL (editor). Properties and Performance of Natural-Fibre Composites, Woodhead Publishing Series in Composites Science and Engineering; 2008. pp. 221–268.

10. Verma D, Gope PC, Shandilya A, et al. Coir fibre reinforcement and application in polymer composites. Journal of Materials and Environmental Science. 2013; 4(2): 263–276.

11. Freitas BR, Braga JO, Orlandi MP, et al. Characterization of coir fiber powder (cocos nucifera L.) as an environmentally friendly inhibitor pigment for organic coatings. Journal of Materials Research and Technology. 2022; 19: 1332–1342. doi: 10.1016/j.jmrt.2022.05.098

12. Rencoret J, Ralph J, Marques G, et al. Structural Characterization of Lignin Isolated from Coconut (Cocos nucifera) Coir Fibers. Journal of Agricultural and Food Chemistry. 2013; 61(10): 2434–2445. doi: 10.1021/jf304686x

13. Alharbi MAH, Hirai S, Tuan HA, et al. Effects of chemical composition, mild alkaline pretreatment and particle size on mechanical, thermal, and structural properties of binderless lignocellulosic biopolymers prepared by hot-pressing raw microfibrillated Phoenix dactylifera and Cocos nucifera fibers and leaves. Polymer Testing. 2020; 84: 106384. doi: 10.1016/j.polymertesting.2020.106384

14. Bensalah H, Raji M, Abdellaoui H, et al. Thermo-mechanical properties of low-cost “green” phenolic resin composites reinforced with surface modified coir fiber. The International Journal of Advanced Manufacturing Technology. 2021; 112(7–8): 1917–1930. doi: 10.1007/s00170-020-06535-9

15. Arrakhiz FZ, El Achaby M, Kakou AC, et al. Mechanical properties of high density polyethylene reinforced with chemically modified coir fibers: Impact of chemical treatments. Materials & Design. 2012; 37: 379–383. doi: 10.1016/j.matdes.2012.01.020

16. Mir SS, Hasan SMN, Hossain MdJ, et al. Chemical Modification Effect on the Mechanical Properties of Coir Fiber. Engineering Journal. 2012; 16(2): 73–84. doi: 10.4186/ej.2012.16.2.73

17. Biswas S, Kindo S, Patnaik A. Effect of fiber length on mechanical behavior of coir fiber reinforced epoxy composites. Fibers and Polymers. 2011; 12(1): 73–78. doi: 10.1007/s12221-011-0073-9

18. Saha P, Manna S, Chowdhury SR, et al. Enhancement of tensile strength of lignocellulosic jute fibers by alkali-steam treatment. Bioresource Technology. 2010; 101(9): 3182–3187. doi: 10.1016/j.biortech.2009.12.010

19. Shibata S, Cao Y, Fukumoto I. Flexural modulus of the unidirectional and random composites made from biodegradable resin and bamboo and kenaf fibres. Composites Part A: Applied Science and Manufacturing. 2008; 39(4): 640–646. doi: 10.1016/j.compositesa.2007.10.021

20. Valášek P, D’Amato R, Müller M, et al. Mechanical properties and abrasive wear of white/brown coir epoxy composites. Composites Part B: Engineering. 2018; 146: 88–97. doi: 10.1016/j.compositesb.2018.04.003

21. Dixit S, Goel R, Dubey A, et al. Natural Fibre Reinforced Polymer Composite Materials—A Review. Polymers from Renewable Resources. 2017; 8(2): 71–78. doi: 10.1177/204124791700800203

22. Udhayasankar R, Karthikeyan B. A review on coconut shell reinforced composites. International Journal of Chemtech Research. 2015; 8(11): 624–637.

23. Sapuan SM, Harimi M, Maleque M. Mechanical properties of epoxy/coconut shell filler particle composites. Arabian Journal for Science and Engineering. 2003; 28(2): 171–182.

24. Frihart CR. Epoxy adhesives from natural materials. In: Dunky M, Mittal KL (editors). Biobased Adhesives: Sources, Characteristics and Applications. Scrivener Publishing LLC; 2023. pp. 367–393.

25. Rahman MdM, Akhtarul Islam M. Application of epoxy resins in building materials: progress and prospects. Polymer Bulletin. 2021; 79(3): 1949–1975. doi: 10.1007/s00289-021-03577-1

26. Auad ML, Zhao L, Shen H, et al. Flammability properties and mechanical performance of epoxy modified phenolic foams. Journal of Applied Polymer Science. 2007; 104(3): 1399–1407. doi: 10.1002/app.24405

27. Verma C, Olasunkanmi LO, Akpan ED, et al. Epoxy resins as anticorrosive polymeric materials: A review. Reactive and Functional Polymers. 2020; 156: 104741. doi: 10.1016/j.reactfunctpolym.2020.104741

28. Saba N, Jawaid M, Alothman OY, et al. Recent advances in epoxy resin, natural fiber-reinforced epoxy composites and their applications. Journal of Reinforced Plastics and Composites. 2015; 35(6): 447–470. doi: 10.1177/0731684415618459

29. Karnani R, Krishnan M, Narayan R. Biofiber—reinforced polypropylene composites. Polymer Engineering & Science. 1997; 37(2): 476–483. doi: 10.1002/pen.11691

30. Faruqui AN, Manikandan P, Sato T, et al. Mechanical milling and synthesis of Mg-SiC composites using underwater shock consolidation. Metals and Materials International. 2012; 18(1): 157–163. doi: 10.1007/s12540-012-0019-9

31. Adhikari RK, Gowda BSK. Exploration of mechanical properties of banana/jute hybrid polyester composite. Materials Today: Proceedings. 2017; 4(8): 7171–7176. doi: 10.1016/j.matpr.2017.07.043

32. Colom X, Carrasco F, Pagès P, et al. Effects of different treatments on the interface of HDPE/lignocellulosic fibre composites. Composites Science and Technology. 2003; 63(2): 161–169. doi: 10.1016/S0266-3538(02)00248-8

33. Olumuyiwa AJ, Isaac TS, Samuel SO. Study of Mechanical Behaviour of Coconut Shell Reinforced Polymer Matrix Composite. Journal of Minerals and Materials Characterization and Engineering. 2012; 11(08): 774–779. doi: 10.4236/jmmce.2012.118065

34. Jawaid M, Khalil HA, Bakar AA, et al. Effect of jute fibre loading on the mechanical and thermal properties of oil palm–epoxy composites. Journal of Composite Materials. 2012; 47(13): 1633–1641. doi: 10.1177/0021998312450305

35. Salleh Z, Hyie KM, Yunus S, et al. Tensile and Impact Strength of Coir Fibre Reinforced Polypropylene Composites: Effect of Different Temperature Conditions. Applied Mechanics and Materials. 2015; 763: 25–29. doi: 10.4028/www.scientific.net/amm.763.25

36. Adeniyi AG, Onifade DV, Ighalo JO, et al. A review of coir fiber reinforced polymer composites. Composites Part B: Engineering. 2019; 176: 107305. doi: 10.1016/j.compositesb.2019.107305

37. Ng YR, Shahid SNAM, Nordin NIAA. The effect of alkali treatment on tensile properties of coir/polypropylene biocomposite. IOP Conference Series: Materials Science and Engineering. 2018; 368: 012048. doi: 10.1088/1757-899x/368/1/012048

38. Tham LM, Gupta M, Cheng L. Effect of limited matrix—reinforcement interfacial reaction on enhancing the mechanical properties of aluminium–silicon carbide composites. Acta Materialia. 2001; 49(16): 3243–3253. doi: 10.1016/S1359-6454(01)00221-X

39. Saba N, Jawaid M. Epoxy resin based hybrid polymer composites. In: Thakur VK, Thakur MK, Pappu A (editors). Hybrid Polymer Composite Materials Properties and Characterisation. Woodhead Publishing; 2017. pp. 57–82.

40. Sadeq NS, Mohammadsalih ZG, Mohammed RH. Effect of grain size on the structure and properties of coir epoxy composites. SN Applied Sciences. 2020; 2(7). doi: 10.1007/s42452-020-2991-x

41. Chaudari P, Gajare K, Kulkarni MDS. Epoxy resin based egg shell powder and coconut coir fibre composites. Journal of Adhesion Science and Technology. 2022; 9(6): 3296–3301.

42. Mittal M, Chaudhary R. Experimental investigation on the mechanical properties and water absorption behavior of randomly oriented short pineapple/coir fiber-reinforced hybrid epoxy composites. Materials Research Express. 2018; 6(1): 015313. doi: 10.1088/2053-1591/aae944

43. Singh Y, Singh J, Sharma S, et al. Fabrication and characterization of coir/carbon-fiber reinforced epoxy based hybrid composite for helmet shells and sports-good applications: influence of fiber surface modifications on the mechanical, thermal and morphological properties. Journal of Materials Research and Technology. 2020; 9(6): 15593–15603. doi: 10.1016/j.jmrt.2020.11.023

44. Virk GS, Singh B, Singh Y, et al. Abrasive water jet machining of coir fibre reinforced epoxy composites: a review. Functional Composites and Structures. 2022; 4(1): 014001. doi: 10.1088/2631-6331/ac586c