Research Article

EFFECT OF NANOCLAY (HALLOYSITE) ON THE MECHANICAL PROPERTIES OF RECYCLED POLYPROPYLENE FILLED NAOH TREATED MAIZE COB POWDER COMPOSITES

Muhammad A.1*, Abdullahi, D2, Musa M. B.3, Nuhu L.4, Hamza A.5
1 Department of Polymer and Textile Technology, Kaduna Polytechnic, Kaduna
2 Department of Polymer and Textile Engineering, Ahmadu Bello University (ABU), Zaria, Nigeria
3 Department of Polymer and Textile Engineering, Ahmadu Bello University, Zaria, Nigeria
4 Department of Polymer and Textile Engineering, Ahmadu Bello University, Zaria
5 Department of Chemistry, Ahmadu Bello University, Zaria
* Corresponding author: adamubappa1@gmail.com
Published: Aug, 2025
DOI: 10.67637/njt.2025.6dmel01h
Pages: 97-107
Views: 17
Downloads: 27

Abstract

This study investigates the influence of halloysite nanoclay (NC) on the mechanical properties of recycled polypropylene (rPP) composites reinforced with untreated maize cob powder (UMCP) and NaOH-treated maize cob powder (NaOH TMCP). Composites were fabricated with filler loadings of 10–40 wt% at particle sizes of 100–500 µm, and NC additions of 2–8 wt%, using two-roll mill and compression molding machines. Mechanical characterizations included tensile strength, elongation at break, tensile modulus, flexural strength, flexural modulus, hardness, and impact strength were carried out on the fabricated samples. Results demonstrate that NaOH treatment significantly enhances interfacial adhesion, leading to improved tensile strength (up to 25.32 MPa at 20 wt% TMCP, 100 µm), flexural strength (up to 47.0 MPa at 20 wt% TMCP, 4 wt% NC), hardness (up to 86.9% at 500 µm, 8 wt% NC), and moduli, while reducing elongation at break and impact strength due to increased brittleness. Optimal performance was achieved at 20 wt% filler loading, 100 µm particle size, and 2–4 wt% NC, with larger particles favoring hardness but compromising toughness. The hybrid reinforcement system offers a sustainable approach for valorizing agricultural waste in eco-friendly composites for automotive, packaging, and structural applications, balancing stiffness and processability.

Keywords

Recycled polypropylene Maize cob powder Halloysite nanoclay NaOH treatment Mechanical properties Biocomposites

References

  1. Ahmad, M. N., & Puasa, M. N. (2025). Mechanical and thermal properties of coconut (Cocos nucifera)-reinforced polypropylene composite. Engineering, 6 (11), Article 299. [https://doi.org/10.3390/eng6110299](https://www.google.com/search?q=https://doi.org/10.3390/eng6110299)
  2. Alexandre, M., & Dubois, P. (2000). Polymer-layered silicate nanocomposites: Preparation, properties and uses of a new class of materials. Materials Science and Engineering: R: Reports, 28 (1-2), 1-63. [https://doi.org/10.1016/S0927-796X(00)00012-7](https://www.google.com/search?q=https://doi.org/10.1016/S0927-796X(00)00012-7)
  3. Ayrilmis, N., Buyuksari, U., Avci, E., & Koc, E. (2013). Utilization of pine cone flour as a filler in polypropylene composites. Journal of Reinforced Plastics and Composites, 32 (8), 569-576. [https://doi.org/10.1177/0731684413476164](https://www.google.com/search?q=https://doi.org/10.1177/0731684413476164)
  4. ASTM International. (2017). ASTM D790-17: Standard test methods for flexural properties of unreinforced and reinforced plastics and electrical insulating materials. ASTM International.
  5. ASTM International. (2018). ASTM D6110-18: Standard test method for determining the Charpy impact resistance of notched specimens of plastics. ASTM International.
  6. ASTM International. (2021). ASTM E384-21: Standard test method for microindentation hardness of materials. ASTM International.
  7. ASTM International. (2022). ASTM D638-22: Standard test method for tensile properties of plastics. ASTM International.
  8. ASTM International. (2023). Standard test methods for mechanical properties of plastics and composites. ASTM International.
  9. Babji, R., Umamaheswara Reddy. M., & Shakthivel, S. (2020). Characteristic investigation and comparison between Vetiver fiber-reinforced polypropylene and polyethylene with coconut shell powder and maleic anhydride as filler and coupling agents. Materials Today: Proceedings, 24 (Part 4). 2339-2351. [https://doi.org/10.1016/j.matpr.2020.04.540](https://www.google.com/search?q=https://doi.org/10.1016/j.matpr.2020.04.540)
  10. Barbosa, L. G., Piaia, M., & Ceni, G. H. (2017). Analysis of impact and tensile properties of recycled polypropylene. International Journal of Materials Engineering, 7, 117-120.
  11. Bledzki, A. K., & Gassan, J. (1999). Composites reinforced with cellulose-based fibres. Progress in Polymer Science, 24 (2), 221-274. [https://doi.org/10.1016/S0079-6700(98)00018-5](https://www.google.com/search?q=https://doi.org/10.1016/S0079-6700(98)00018-5)
  12. Chukwudike, O., Okechukwu, O., Charles, A., & Genevieve, O. (2017). Morphology and physical/end-use properties of recycled polypropylene-corn cob powder. International Journal of Engineering and Technologies. [https://www.researchgate.net/publication/318731801](https://www.google.com/search?q=https://www.researchgate.net/publication/318731801)
  13. Daramola, O. O., Akinwande, A. A.. Adediran, A. A., Balogun, O. A., Olajide, J. L., Adedoyin, K. J., Adewuyi, B. O., & Jen, T. C. (2023). Optimization of the mechanical properties of polyester/coconut shell ash (CSA) composite for light-weight engineering applications. Scientific Reports, 13, 1066. [https://doi.org/10.1038/s41598-022-26632-x](https://www.google.com/search?q=https://doi.org/10.1038/s41598-022-26632-x)
  14. Dinh, T. M., Chang, K. H., Chen, Y. L., & Huang, S. T. (2018). Effect of cellulose filler size on interfacial adhesion in polypropylene composites. Journal of Applied Polymer Science, 135 (28), 46501. [https://doi.org/10.1002/app.46501](https://www.google.com/search?q=https://doi.org/10.1002/app.46501)
  15. Du, M., Guo, B., & Jia, D. (2006). Newly emerging applications of halloysite nanotubes: A review. Polymer International, 59 (5), 574-582. [https://doi.org/10.1002/pi.2754](https://www.google.com/search?q=https://doi.org/10.1002/pi.2754)
  16. Faruk, O., Bledzki, A. K., Fink, H. P., & Sain, M. (2012). Biocomposites reinforced with natural fibers: 2000-2010. Progress in Polymer Science, 37 (11), 1552-1596. [https://doi.org/10.1016/j.progpolymsci.2012.04.003](https://doi.org/10.1016/j.progpolymsci.2012.04.003)
  17. Galgali, G., Agarwal, S., & Lele, A. (2004). Effect of clay orientation on the tensile modulus of polypropylene-nanoclay composites. Polymer, 45 (17), 6059-6069. [https://doi.org/10.1016/j.polymer.2004.06.012](https://www.google.com/search?q=https://doi.org/10.1016/j.polymer.2004.06.012)
  18. Golmakani, M. E., Wiczenbach, T., Malikan, M., Mahoori, S. M., & Eremeyev, V. A. (2021). Experimental and numerical investigation of tensile and flexural behavior of nanoclay wood-plastic composite. Materials, 14 (11), Article 2773. [https://doi.org/10.3390/ma14112773](https://www.google.com/search?q=https://doi.org/10.3390/ma14112773)
  19. Hammajam, A. A., Ismay, N., Crosky, M., Kelly, P., Agboola, H., Kim, J., & Truss, R. (2017). Acetylation effects on mechanical performance of agro-waste composites. Polymer Testing, 63, 328-335. [https://doi.org/10.1016/j.polymertesting.2017.08.034](https://www.google.com/search?q=https://doi.org/10.1016/j.polymertesting.2017.08.034)
  20. Hammajam, A. A., Nur, I. Z., Salit, S. M., & Zulkeffle, L. (2020). The effect of fiber sizes on mechanical properties of millet husk (Pennisetum glaucum) fiber filled high density polyethylene composites. Arid Zone Journal of Engineering, Technology & Environment, 16 (1), 37-47.
  21. Jamila, B. A., Abdullahi, D., Musa, M. B., Paul, M., & Zurina, B. M. (2020). Effect of maize cob nanofibre on mechanical and morphological properties of HDPE/HD-g-MAH/nanocomposites. Sule Lamido University Journal of Science and Technology (SLUST), 1 (1).
  22. Kabir, M. M., Wang, H., Lau, K. T., & Cardona, F. (2012). Chemical treatments on plant-based natural fibre reinforced polymer composites: An overview. Composites Part B: Engineering, 43 (7), 2883-2892. [https://doi.org/10.1016/j.compositesb.2012.04.053](https://www.google.com/search?q=https://doi.org/10.1016/j.compositesb.2012.04.053)
  23. Karuppuchamy, S. (2015). Thermo-mechanical properties of coconut shell powder reinforced plastic composites. International Journal of ChemTech Research, 8 (6), 852-857.
  24. Khakifirouz, A., Samariha, A., Karbaschi A., Asadollahi Benakachi, M., & Beigloo, J. G. (2019). Nanoclay's influence on mechanical and thermal properties of a polypropylene/poplar wood flour nanocomposite. BioResources, 14 (4). 8267-8277. [https://doi.org/10.15376/biores.14.4.8267-8277](https://www.google.com/search?q=https://doi.org/10.15376/biores.14.4.8267-8277)
  25. Kord, B., & Hosseini Kiakojouri, S. M. (2011). Effect of nanoclay dispersion on physical and mechanical properties of wood flour/ polypropylene/ glass fiber hybrid composites. BioResources, 6 (2), 1741-1751.
  26. Kumar, A., Singh, P., & Meena, S. (2014). Chemical treatment of natural fibers: Effects on mechanical properties and water absorption behavior. Journal of Applied Polymer Science, 131 (6), 396-407. [https://doi.org/10.1002/app.39765](https://www.google.com/search?q=https://doi.org/10.1002/app.39765)
  27. Kumar, K. K., Ramesh, B. P., & Raja, N. R. K. (2014). Evaluation of flexural and tensile properties of short kenaf fiber reinforced green composites. International Journal of Advanced Mechanical Engineering, 4 (4), 371-380.
  28. Manjunatha Chary, G. H., & Sabeel Ahmed, K. (2017). Experimental characterization of coconut shell particle reinforced epoxy composites. Journal of Materials and Environmental Science, 8 (5), 1661-1667. [http://www.jmaterenvironsci.com](http://www.jmaterenvironsci.com)
  29. Mohammad, J. N., Asad, M., Ali, Z., & Hasan, A. (2012). Particle size effects on dispersion and mechanical properties of microcrystalline cellulose-polypropylene composites. Composites Part A: Applied Science and Manufacturing, 43 (6), 858-865. [https://doi.org/10.1016/j.compositesa.2012.01.019](https://www.google.com/search?q=https://doi.org/10.1016/j.compositesa.2012.01.019)
  30. Nabi Saheb, D., & Jog, J. P. (1999). Natural fiber polymer composites: A review. Advances in Polymer Technology, 18 (4), 351-363. [https://doi.org/10.1002/(SICI)1098-2329(199924)18:4](https://www.google.com/search?q=https://doi.org/10.1002/(SICI)1098-2329(199924)18:4)<351::AID-ADV6>3.0.CO;2-X
  31. Nagaraja, K. C., Rajanna, S., Prakash, G. S., & Koppad, P. G. (2020). Improvement of mechanical and thermal properties of hybrid composites through addition of halloysite nanoclay for light weight structural applications. Materials Today: Proceedings.
  32. Nuhu, L., Abdullahi, D., Musa, M. B., & Kogo, A. (2020). Effect of particle size on the mechanical properties of waste polypropylene filled date seed particulate composite. World Science Journal, Kaduna State University.
  33. Obasi, H. C., Mark, U. C., & Mark, U. (2021). Improving the mechanical properties of polypropylene composites with coconut shell particles. Composites and Advanced Materials. [https://doi.org/10.1177/26349833211007497](https://www.google.com/search?q=https://doi.org/10.1177/26349833211007497)
  34. Obasi, H. C., McDonald, A. G., & Kanayo, K. (2021). Agglomeration effects on mechanical properties of natural fiber-reinforced composites. Composites Part B: Engineering, 215, 108768. [https://doi.org/10.1016/j.compositesb.2021.108768](https://www.google.com/search?q=https://doi.org/10.1016/j.compositesb.2021.108768)
  35. Onuoha, C., Onyemaobi, O. O., Anyakwo, C. N., & Onueghu, C. G. (2017). Effect of filler content and particle size on the mechanical properties of corncob powder filled polypropylene composites. International Journal of Scientific Engineering and Applied Science, 3(4).
  36. Onuoha, G. N. (2014). Filler loading thresholds in natural fiber composites. Journal of Composite Materials, 48 (15), 1865-1875. [https://doi.org/10.1177/0021998313490345](https://www.google.com/search?q=https://doi.org/10.1177/0021998313490345)
  37. Onuoha, C., Hornsby, P., McNally, T., & McCartney, A. (2017). Interfacial stress concentration effects in particulate-filled thermoplastics. Mechanics of Materials, 113, 43-52. [https://doi.org/10.1016/j.mechmat.2017.07.015](https://www.google.com/search?q=https://doi.org/10.1016/j.mechmat.2017.07.015)
  38. Pavlidou, S., & Papaspyrides, C. D. (2008). A review on polymer-layered silicate nanocomposites. Progress in Polymer Science, 33 (12), 1119-1198. [https://doi.org/10.1016/j.progpolymsci.2008.07.008](https://www.google.com/search?q=https://doi.org/10.1016/j.progpolymsci.2008.07.008)
  39. Prashantha, K., Lacrampe, M. F., & Krawczak, P. (2011). Processing and characterization of halloysite nanotubes filled polypropylene nanocomposites based on a masterbatch route: Effect of halloysites treatment on structural and mechanical properties. Express Polymer Letters, 5 (4), 295-307.
  40. Ramos, R. R., Siqueira, D. D., Wellen, R., Leite, I., Glenn, G. M., & Medeiros, E. (2019). Development of green composites based on polypropylene and corncob agricultural residue. Journal of Polymers and the Environment, 27, 1677-1685. [https://doi.org/10.1007/s10924-019-01462-7](https://www.google.com/search?q=https://doi.org/10.1007/s10924-019-01462-7)
  41. Ray, S. S., & Okamoto, M. (2003). Polymer/layered silicate nanocomposites: A review from preparation to processing. Progress in Polymer Science, 28 (11), 1539-1641. [https://doi.org/10.1016/S0079-6700(03)00015-9](https://www.google.com/search?q=https://doi.org/10.1016/S0079-6700(03)00015-9)
  42. Yang, H. S., Kim, H. J., Son, J., Park, H. J., Lee, B. J., & Hwang, T. S. (2006). Rice-husk flour filled polypropylene composites; mechanical and morphological study. Composite Structures, 63 (3-4), 305-312. [https://doi.org/10.1016/j.compstruct.2003.09.002](https://www.google.com/search?q=https://doi.org/10.1016/j.compstruct.2003.09.002)
  43. Zawawi, E. Z. E., Noor Hafizah, A. H., Romli, A. Z., Yuliana, N. Y., & Bonnia, N. N. (2021). Effect of nanoclay on mechanical and morphological properties of poly(lactide) acid (PLA) and polypropylene (PP) blends. Materials Today: Proceedings, 46 (Part 4), 1778-1782. [https://doi.org/10.1016/j.matpr.2021.05.327](https://www.google.com/search?q=https://doi.org/10.1016/j.matpr.2021.05.327)
  44. Žiganova, M., Merijs-Meri, R., Zicāns, J., Ivanova, T., Bochkov, I., Kalniņš, M., Błędzki, A. K., & Danilovas, P. P. (2022). Characterisation of nanoclay and spelt husk microfiller-modified polypropylene composites. Polymers, 14 (20), 4332. [https://doi.org/10.3390/polym14204332](https://www.google.com/search?q=https://doi.org/10.3390/polym14204332)
How to Cite

A., M., D, A., B., M. M., L., N., & A., H. (2025). EFFECT OF NANOCLAY (HALLOYSITE) ON THE MECHANICAL PROPERTIES OF RECYCLED POLYPROPYLENE FILLED NAOH TREATED MAIZE COB POWDER COMPOSITES. Nigerian Journal of Textiles, 11(1), 97-107. https://doi.org/10.67637/njt.2025.6dmel01h

M. A., A. D, M. M. B., N. L., and H. A., "EFFECT OF NANOCLAY (HALLOYSITE) ON THE MECHANICAL PROPERTIES OF RECYCLED POLYPROPYLENE FILLED NAOH TREATED MAIZE COB POWDER COMPOSITES," Nigerian Journal of Textiles, vol. 11, no. 1, pp. 97-107, August 2025. doi: 10.67637/njt.2025.6dmel01h

Share this article:
Facebook X / Twitter LinkedIn
Download PDF View Full Text (PDF) Back to Articles