The objective of this study is to develop biodegradable mulch films containing PLA and modified natural rubber and study the mechanical behaviour of the biodegradable mulch films containing polylactic acid and modified natural rubber under real field conditions. The present study investigated the effect of different component ratios of the mechanical and biodegradable properties on the bio-based mulching film. Bio-based mulching films were prepared using blown film extrusion with extruder barrel temperature settings ranging between 167 to 170 C and an extruder pressure of 119 bar. The blend composition consisted of Poly (Butylene Adipate-co-Terephthalate) (PBA T), Epoxidized Natural Rubber (ENR), and Polylactic Acid (PLA). The effect of real field conditions on the mechanical properties of the mulching films during the time of cultivation was investigated using a universal testing machine and the pendulum tear method. The mechanical property deterioration of the PLA/ENR mulching films under real field conditions was due to biodegradation caused by biological activity, temperature, and humidity. The results show that the performance of the biodegradable mulching films under actual user conditions for six months was still effective, and the quality of the fruit trees and flowers improved when using the PLA/ENR mulching films.

1. C. Bastioli, Handbook of Biodegradable Polymers. Munich, Germany: Walter de Gruyter GmbH & Co, 2020.
2. A. L. Andraday, Plastics and the Environment. Hoboken, NJ: Wiley & Sons Publication„ 2003.
3. Plastemart. Consumption of agricultural film in Europe and solution for recycling of agri plastic. [Online]. Available: https://bit.ly/367zwW7
4. H. K. Celik, G. Kunt, A. E. W. Rennie, and I. Akinci, “Non-linear fem-based shattering simulation of shelled edible agricultural products: Walnut shattering by nut cracker hand tool,” International Journal of Technology and Engineering Studies, vol. 3, no. 2, pp. 84–92, 2017. doi: https://doi.org/10.20469/ijtes.3.40006-2
5. S. E. Widodo, M. Kamal, F. Zulferiyenni, M. Lerizka, and M. Y. Sari, “Postharvest applications of chitosan and plastic wrapping to mangosteen fruits of different fruit stages in affecting fruit shelf-life and qualities,” International Journal of Technology and Engineering Studies, vol. 3, no. 6, pp. 224–228, 2017. doi: https://doi.org/10.20469/ijtes.3.40001-6
6. W. Sanhawong, P. Banhalee, S. Boonsang, and S. Kaewpirom, “Effect of concentrated natural rubber latex on the properties and degradation behavior of cotton-fiber-reinforced cassava starch bio-foam,” Industrial Crops and Products, vol. 108, pp. 756–766, 2017. doi: https://doi.org/10.1016/j.indcrop.2017.07.046
7. P. Kampan, “Sustainability and competitiveness of thailands natural rubber industry in times of global economic flux,” Asian Social Science, vol. 14, no. 1, pp. 169–182, 2018.
8. P. Zhao, W. Liu, Q. Wu, and J. Ren, “Preparation, mechanical, and thermal properties of biodegradable polyesters/poly (lactic acid) blends,” Journal of Nanomaterials, vol. 2010, pp. 1–8, 2010. doi: https://doi.org/10.1155/2010/287082
9. A. Carbonell-Verdu, J. Ferri, F. Dominici, T. Boronat, L. Sanchez-Nacher, R. Balart, and L. Torre, “Manufacturing and compatibilization of PLA/PBAT binary blends by cottonseed oil-based derivatives,” Express Polymer Letters, vol. 12, no. 9, pp. 808–823, 2018. doi: https://doi.org/10.3144/expresspolymlett.2018.69
10. J. Harada, J. R. N. Macedo, G. A. F. Machado, F. Valenzuela-Díaz, E. A. Moura, and D. S. Rosa, “Effects of carbon black incorporation on morphological, mechanical and thermal properties of biodegradable films,” in Characterization of Minerals, Metals, and Materials. New York, NY: Springer, 2016.
11. L. N. Ludueña, A. Vecchio, P. M. Stefani, and V. A. Alvarez, “Extraction of cellulose nanowhiskers from natural fibers and agricultural byproducts,” Fibers and Polymers, vol. 14, no. 7, pp. 1118–1127, 2013. doi: https://doi.org/10.1007/s12221-013-1118-z
12. F. Chivrac, Z. Kadlecová, E. Pollet, and L. Avérous, “Aromatic copolyester-based nano-biocomposites: Elaboration, structural characterization and properties,” Journal of Polymers and the Environment, vol. 14, no. 4, pp. 393–401, 2006. doi: https://doi.org/10.1007/s10924-006-0033-4
13. M. M. Moreno, S. González-Mora, J. Villena, J. A. Campos, and C. Moreno, “Deterioration pattern of six biodegradable, potentially low-environmental impact mulches in field conditions,” Journal of Environmental Management, vol. 200, pp. 490–501, 2017. doi: https://doi.org/10.1016/j.jenvman.2017.06.007
14. M. Hakkarainen, “Aliphatic polyesters: Abiotic and biotic degradation and degradation products,” in Degradable Aliphatic Polyesters. New York, NY: Springer, 2002, pp. 113–138.
15. M. Mistretta, L. Botta, A. Vinci, M. Ceraulo, and F. La Mantia, “Photo-oxidation of polypropylene/graphene nanoplatelets composites,” Polymer Degradation and Stability, vol. 160, pp. 35–43, 2019. doi: https://doi.org/10.1016/j.polymdegradstab.2018.12.003
16. T. Kijchavengkul, R. Auras, M. Rubino, M. Ngouajio, and R. T. Fernandez, “Assessment of aliphatic-aromatic copolyester biodegradable mulch films. Part I: Field study,” Chemosphere, vol. 71, no. 5, pp. 942–953, 2008. doi: https://doi.org/10.1016/j.chemosphere.2007.10.074
17. R. Muthuraj, M. Misra, and A. Mohanty, “Hydrolytic degradation of biodegradable polyesters under simulated environmental conditions,” Journal of Applied Polymer Science, vol. 132, no. 27, pp. 18–29, 2015. doi: https://doi.org/10.1002/app.42189
18. D. Briassoulis, “Mechanical behaviour of biodegradable agricultural films under real field conditions,” Polymer Degradation and Stability, vol. 91, no. 6, pp. 1256–1272, 2006. doi: https://doi.org/10.1016/j.polymdegradstab.2005.09.016
19. Y. Luo, Z. Lin, and G. Guo, “Biodegradation assessment of poly (lactic acid) filled with functionalized titania nanoparticles (PLA/TiO 2) under compost conditions,” Nanoscale research letters, vol. 14, no. 1, pp. 1–10, 2019.
20. M. A. Bardi, M. M. Munhoz, R. A. Auras, and L. D. Machado, “Assessment of UV exposure and aerobic biodegradation of poly (butylene adipate-co-terephthalate)/starch blend films coated with radiation-curable print inks containing degradation-promoting additives,” Industrial Crops and Products, vol. 60, pp. 326–334, 2014. doi: https://doi.org/10.1016/j.indcrop.2014.06.042
21. J.-H. Chen, C.-C. Chen, and M.-C. Yang, “Characterization of nanocomposites of poly (butylene adipate-co-terephthalate) blending with organoclay,” Journal of Polymer Research, vol. 18, no. 6, pp. 2151–2159, 2011.
22. E. Yousif and R. Haddad, “Photodegradation and photostabilization of polymers, especially polystyrene,” SpringerPlus, vol. 2, no. 1, pp. 1–32, 2013.
23. J. E. Pegram and A. L. Andrady, “Outdoor weathering of selected polymeric materials under marine exposure conditions,” Polymer degradation and stability, vol. 26, no. 4, pp. 333–345, 1989. doi: https://doi.org/10.1016/0141-3910(89)90112-2
24. A. Chamas, H. Moon, J. Zheng, Y. Qiu, T. Tabassum, J. H. Jang, M. Abu-Omar, S. L. Scott, and S. Suh, “Degradation rates of plastics in the environment,” ACS Sustainable Chemistry & Engineering, vol. 8, no. 9, pp. 3494–3511, 2020.
25. M. Rapisarda, F. P. La Mantia, M. Ceraulo, M. C. Mistretta, C. Giuffrè, R. Pellegrino, G. Valenti, and P. Rizzarelli, “Photo-oxidative and soil burial degradation of irrigation tubes based on biodegradable polymer blends,” Polymers, vol. 11, no. 9, pp. 14–18, 2019.
26. J. Jian, Z. Xiangbin, and H. Xianbo, “An overview on synthesis, properties and applications of Poly (Butylene-Adipate-co-Terephthalate)-PBAT,” Advanced Industrial and Engineering Polymer Research, vol. 3, no. 1, pp. 19–26, 2020.

T. Nampitch, S. Ouipanich, T. Kaisone, P. Hanthanon, C. Wiphanurat, and Y. Thongjun, & Mechanical property deterioration of PBAT/PLA/ENR mulching films for the cultivation of fruit trees and flowers under real field conditions", International Journal of Technology and Engineering Studies, vol. 6, no. 1, pp. 8–15, 2020. Doi: https://dx.doi.org/10.20469/ijtes.6.10002-1