Basalt Fiber-Reinforced Recycled Polypropylene Composites: Adhesive Joints and Aging Performance

Öz

This study investigates the aging-induced interfacial degradation mechanisms in adhesively bonded single-lap joints (SLJs) fabricated from basalt fiber-reinforced recycled polypropylene (BF/rPP) composites derived from waste materials, with particular emphasis on linking microstructural damage evolution to macroscopic mechanical response. The novelty of the work lies in combining a sustainable BF/rPP system with a systematic correlation among environmental aging, failure morphology, and mechanical performance. Epoxy-bonded joints were subjected to unaged, UV-aged, and hydrothermally aged conditions to simulate accelerated environmental exposure. Tensile testing was used to evaluate mechanical behavior, while scanning electron microscopy (SEM) was employed to identify failure mechanisms. The unaged joints exhibited the highest load-bearing capacity (5732 N) and deformation capability (3.8 mm), governed by cohesive failure, indicating efficient stress transfer across a well-integrated adhesive interface. UV exposure caused only limited reductions in strength (~3%) and displacement (~8%), whereas SEM observations revealed the onset of interfacial degradation accompanied by mixed failure features, including cohesive regions and localized interfacial separation, reflecting early-stage weakening of the adhesive–adherend interface. In contrast, hydrothermal aging resulted in a more pronounced reduction in strength (~16%), governed by moisture- and temperature-induced interfacial degradation. This condition promoted unstable crack propagation through weakened interfacial regions, accompanied by fiber–matrix debonding and localized matrix softening. Although limited ductile deformation features were observed within the adhesive layer, they did not contribute to an improvement in the macroscopic deformation capacity, as premature interfacial failure governed the global response.

Anahtar Kelimeler

• Basalt fiber
• Recycled polypropylene
• Adhesive bonding
• Single-lap joints
• Aging performance

Destekleyen Kurum

Scientific Research Projects Coordination Unit (BAP) of Samsun University

Proje Numarası

BAP.MÜF.5501.2023.001

Etik Beyan

Ethics committee approval was not required for this study because it involved no animal or human subjects.

Teşekkür

This study was supported by the Scientific Research Projects Coordination Unit (BAP) of Samsun University under Project No: BAP.MÜF.5501.2023.001, whose financial contribution is gratefully acknowledged. The authors also sincerely thank the Poelsan R&D team for technical support throughout the project.

Kaynakça

1. Abdelhaleem, A. M., Megahed, M., & Saber, D. (2018). Fatigue behavior of pure polypropylene and recycled polypropylene reinforced with short glass fiber. Journal of Composite Materials, 52(12), 1633–1640. https://doi.org/10.1177/0021998317729888
2. Angyal, A., Miskolczi, N., & Bartha, L. (2007). Petrochemical feedstock by thermal cracking of plastic waste. Journal of Analytical and Applied Pyrolysis, 79(1–2), 409–414. https://doi.org/10.1016/j.jaap.2006.12.031
3. Bolat, Ç., Şükür, E. F., Ergene, B., Yalçın, B., Maraş, S., Karakılınç, U., & Önal, G. (2025). Cutting force and delamination optimization of nanoparticle-reinforced basalt/epoxy multi-scale composites in dry drilling by Taguchi design. Multidiscipline Modeling in Materials and Structures, 21(6), 1261–1279. https://doi.org/10.1108/MMMS-01-2025-0006
4. Bujak, J. W. (2015). Production of waste energy and heat in hospital facilities. Energy, 91, 350–362. https://doi.org/10.1016/j.energy.2015.08.053
5. Chiou, A. H., & Lin, C. H. (2023). Material and mechanical characterization of recycled polypropylene reinforced with different weight percentages of short glass fiber developed by injection molding. Heliyon, 9(9), Article e19403. https://doi.org/10.1016/j.heliyon.2023.e19403
6. Curtzwiler, G. W., Schweitzer, M., Li, Y., Jiang, S., & Vorst, K. L. (2019). Mixed post-consumer recycled polyolefins as a property tuning material for virgin polypropylene. Journal of Cleaner Production, 239, Article 117978. https://doi.org/10.1016/j.jclepro.2019.117978
7. El Hawary, O., Boccarusso, L., Durante, M., Panico, M., & Pinto, F. (2026). Production, repairing and testing of hemp reinforced recycled HDPE composites. Arabian Journal for Science and Engineering 51, 2977–2997. https://doi.org/10.1007/s13369-025-10170-5
8. Fan, Y., Na, J., & Mu, W. (2019). Effect of hygrothermal cycle aging on the mechanical behavior of single-lap adhesive bonded joints. Journal of Wuhan University of Technology-Mater. Sci. Ed., 34, 337–344. https://doi.org/10.1007/s11595-019-2057-3

9. Fan, Y., Wang, X., Liu, Y., Liu, Z., Xi, G., & Shangguan, L. (2022). Study on the effect of salt solution on durability of basalt-fiber-reinforced polymer joints in high-temperature environment. Polymers, 14(11), Article 2250. https://doi.org/10.3390/polym14112250
10. Gall, M., Freudenthaler, P. J., Fischer, J., & Lang, R. W. (2021). Characterization of composition and structure–property relationships of commercial post-consumer polyethylene and polypropylene recyclates. Polymers, 13(10), 1574. https://doi.org/10.3390/polym13101574
11. Grigorescu, R. M., Ghioca, P., Iancu, L., David, M. E., Andrei, E. R., Filipescu, I. M., Ion, R. M., Vuluga, Z., Anghel, I., Sofran, E. E., Nicolae, C. A., Gabor, A. R., Gheboianu, A., & Bucurica, I. A. (2020). Development of thermoplastic composites based on recycled polypropylene and waste printed circuit boards. Waste Management, 118, 391–401. https://doi.org/10.1016/j.wasman.2020.08.050
12. Harussani, M. M., Sapuan, S. M., Rashid, U., Khalina, A., & Ilyas, R. A. (2022). Pyrolysis of polypropylene plastic waste into carbonaceous char: Priority of plastic waste management amidst COVID-19 pandemic. Science of The Total Environment, 803, Article 149911. https://doi.org/10.1016/j.scitotenv.2021.149911
13. Hashemnejad, M., & Doshi, A. (2024). Quantifying the content of various types of polypropylene in high density polyethylene blends. Polymer Testing, 139, Article 108577. https://doi.org/10.1016/j.polymertesting.2024.108577
14. Hoque, M., Sultana, S., Sarker, M., & Islam, Z. (2023). Recycling waste polypropylene to produce new composite materials with jute reinforcements. Advances in Materials Science, 23(3), Article 77. https://doi.org/10.2478/adms-2023-0014
15. Ibrahim, I.D., Jamiru, T., Sadiku, R. E., Kupolati, W. K., & Agwuncha, S. C. (2017). Dependency of the mechanical properties of sisal fiber reinforced recycled polypropylene composites on fiber surface treatment, fiber content and nanoclay. Journal of Polymers and the Environment, 25, 427–434. https://doi.org/10.1007/s10924-016-0823-2
16. ICNIRP. (2004). Guidelines on limits of exposure to ultraviolet radiation of wavelengths between 180 nm and 400 nm (incoherent optical radiation). Health Physics, 87(2), 171–186. https://doi.org/10.1097/00004032-200408000-00006
17. Jojibabu, P., Ram, G. D. J., Deshpande, A. P., & Bakshi, S. R. (2017). Effect of carbon nano-filler addition on the degradation of epoxy adhesive joints subjected to hygrothermal aging. Polymer Degradation and Stability, 140, 84–94. https://doi.org/10.1016/j.polymdegradstab.2017.04.017
18. Jubinville, D., Esmizadeh, E., Tzoganakis, C., & Mekonnen, T. (2021). Thermo-mechanical recycling of polypropylene for the facile and scalable fabrication of highly loaded wood plastic composites. Composites Part B: Engineering, 219, Article 108873. https://doi.org/10.1016/j.compositesb.2021.108873
19. Kang, D., Lee, J., Moon, C., & Kim, H. I. (2021). Improvement in mechanical properties of recycled polypropylene composite by controlling the length distribution of glass fibers. Polymer Composites, 42(5), 2171–2179. https://doi.org/10.1002/pc.25966
20. Korkmaz, Y., & Gültekin, K. (2022). Effect of UV irradiation on epoxy adhesives and adhesively bonded joints reinforced with BN and B4C nanoparticles. Polymer Degradation and Stability, 202, Article 110004. https://doi.org/10.1016/j.polymdegradstab.2022.110004
21. Krajenta, J., & Pawlak, A. (2024). Crystallization of the β-form of polypropylene from the melt with reduced entanglement of macromolecules. Polymers, 16(12), Article 1710. https://doi.org/10.3390/polym16121710
22. Li, J., Li, C., Liao, Q., & Xu, Z. (2019). Environmentally-friendly technology for rapid on-line recycling of acrylonitrile-butadiene-styrene, polystyrene and polypropylene using near-infrared spectroscopy. Journal of Cleaner Production, 213, 838–844. https://doi.org/10.1016/j.jclepro.2018.12.160
23. Lin, Y. C., Chen, X., Zhang, H. J., & Wang, Z. P. (2006). Effects of hygrothermal aging on epoxy-based anisotropic conductive film. Materials Letters, 60(24), 2958–2963. https://doi.org/10.1016/j.matlet.2006.02.024
24. Milosevic, M., Stoof, D., & Pickering, K. (2017). Characterizing the mechanical properties of fused deposition modelling natural fiber recycled polypropylene composites. Journal of Composites Science, 1(1), Article 7. https://doi.org/10.3390/jcs1010007
25. Mu, W., Na, J., Wang, G., Tan, W., Xu, Q., & Feng, Y. (2020). Rapid prediction method of failure load for hygrothermally aged CFRP – Aluminum alloy single lap joints. Composite Structures, 252, Article 112603. https://doi.org/10.1016/j.compstruct.2020.112603
26. Na, J., Mu, W., Qin, G., Tan, W., & Pu, L. (2018). Effect of temperature on the mechanical properties of adhesively bonded basalt FRP-aluminum alloy joints in the automotive industry. International Journal of Adhesion and Adhesives, 85, 138–148. https://doi.org/10.1016/j.ijadhadh.2018.05.027
27. Niu, R., Yang, Y., Liu, Z., Ding, Z., Peng, H., & Fan, Y. (2023). Durability of two epoxy adhesive BFRP joints dipped in seawater under high temperature environment. Polymers, 15(15), Article 3232. https://doi.org/10.3390/polym15153232
28. Saikrishnan, S., Jubinville, D., Tzoganakis, C., & Mekonnen, T. H. (2020). Thermo-mechanical degradation of polypropylene (PP) and low-density polyethylene (LDPE) blends exposed to simulated recycling. Polymer Degradation and Stability, 182, Article 109390. https://doi.org/10.1016/j.polymdegradstab.2020.109390
29. Stoian, A. S., Gabor, A. R., Albu, A. M., Nicolae, C. A., Raditoiu, V., & Panaitescu, D. M. (2019). Recycled polypropylene with improved thermal stability and melt processability. Journal of Thermal Analysis and Calorimetry, 138, 2469–2480. https://doi.org/10.1007/s10973-019-08824-2
30. Sukur, E. F., & Onal, G. (2020). Graphene nanoplatelet modified basalt/epoxy multi-scale composites with improved tribological performance. Wear, 460–461, Article 203481. https://doi.org/10.1016/j.wear.2020.203481
31. Sukur, E. F., & Onal, G. (2021). Long-term salt-water durability of GNPs reinforced basalt-epoxy multiscale composites for marine applications. Tribology International, 158, Article 106910. https://doi.org/10.1016/j.triboint.2021.106910
32. Sukur, E. F., Elmas, S., Eskizeybek, V., Sas, H. S., & Yildiz, M. (2023). An experimental implication of long‐term hot‐wet‐aged carbon fiber/polyether ketone ketone composites: The impact of automated fiber placement process parameters and process‐induced defects. Journal of Applied Polymer Science, 140(29), Article e54076. https://doi.org/10.1002/app.54076
33. Ulus, H. (2021). The impact of seawater aging on basalt/graphene nanoplatelet-epoxy composites: Performance evaluating by Dynamic Mechanical Analysis (DMA) and short beam shear (sbs) tests. NÖHÜ Mühendislik Bilimleri Dergisi, 10(1), 412–419. https://doi.org/10.28948/ngumuh.791161
34. Ulus, H. (2022). An experimental assessment of hybrid bolted/bonded basalt fiber reinforced polymer composite joints’ temperature-dependent mechanical performances by static and dynamic mechanical analyses. International Journal of Adhesion and Adhesives, 114, Article 103120. https://doi.org/10.1016/j.ijadhadh.2022.103120
35. Ulus, H., Kaybal, H. B., Cacık, F., Eskizeybek, V., & Avci, A. (2022). Effect of long‐term stress aging on aluminum‐BFRP hybrid adhesive joint’s mechanical performance: Static and dynamic loading scenarios. Polymer Composites, 43(8), 5301–5318. https://doi.org/10.1002/pc.26828
36. Wang, X., Liang, Y., Pu, Z., He, J., & Yang, S. (2024). Transforming waste to treasure: Superhydrophobic coatings from recycled polypropylene for high-value application. Progress in Organic Coatings, 188, Article 108248. https://doi.org/10.1016/j.porgcoat.2024.108248
37. Zhao, W., Kumar Kundu, C., Li, Z., Li, X., & Zhang, Z. (2021). Flame retardant treatments for polypropylene: Strategies and recent advances. Composites Part A: Applied Science and Manufacturing, 145, Article 106382. https://doi.org/10.1016/j.compositesa.2021.106382
38. Zolfaghari, E., Infurna, G., Alessi, S., Dispenza, C., & Dintcheva, N. (2024). Sustainable composites from waste polypropylene added with thermoset composite waste or recovered carbon fibres. Polymers, 16(20), Article 2922. https://doi.org/10.3390/polym16202922