Biodegradation of Polylactic Acid (PLA) in Soils

Abstract

Biodegradable polymers are alternatives to petroleum-derived polymers. Polylactic acid (PLA) is the most widely used biodegradable polymer derived from renewable resources. According to the traditional waste management approach, 60% of all plastic ever produced ends up in landfills or natural environments. This has became an important environmental problem. End-of-life options for PLAs as an alternative to petroleum-based plastics are discussed in the context of circular economy. It is very important to understand the behaviour of these biodegradable polymers in soil after they become waste. In this study, the PLA samples were subjected to biodegradation in the soil at ambient temperature according to ASTM 5988 standard. Biodegradation in PLA after 90 days; physical appearances, mass loss, FTIR and SEM were evaluated. The weight loss rate of the samples after biodegradation was 0.9%. The physical appearances of PLA samples, FTIR and SEM results showed that the biodegradation rates of PLA in soil and ambient temperature are slow and it takes a longer time to fully degrade in this environment.

Keywords

• ASTM 5988
• Polylactic acid
• Biodegradation
• Soil

TOPRAKLARDA POLİLAKTİK ASİTİN (PLA) BİYOBOZUNMASI

Abstract

Biyobozunur polimerler, petrol türevli polimerlerin yerini almaya bir alternatiftir. Polilaktik asit (PLA), yenilenebilir kaynaklardan elde edilen ve biyolojik olarak parçalanabilen en yaygın kullanılan polimerdir. Kullanılan geleneksel atık yönetimi yaklaşımına göre, şimdiye kadar üretilen tüm plastiğin %60'ı, atık sahalarına veya doğal ortamlara atılmıştır. Bu da önemli bir çevre sorunu haline gelmiştir. Petrol bazlı plastiklere alternatif olan PLA’ların kullanım ömrü sonu seçenekleri, döngüsel ekonomi bağlamında tartışılmaktadır. Biyobozunur özellikleri olan bu polimerlerin, atık haline geldikten sonra toprak içerisindeki davranışlarını anlamak oldukça önemlidir. Bu çalışmada PLA numuneleri, ortam sıcaklığında, toprak içerisinde, ASTM 5988-18 standardına göre biyobozunmaya tabi tutulmuştur. 90 günlük inkübasyon süresinden sonra PLA’daki biyobozunma; fiziksel görünüş, kütle kaybı, FTIR ve SEM ile değerlendirilmiştir. Numunelerin, biyobozunmadan sonra ağırlık kaybı oranı %0,9’dur. PLA örneklerinin fiziksel görünüşleri, FTIR ve SEM sonuçları, PLA’nın toprakta ve ortam sıcaklığında biyobozunma hızlarının yavaş olduğunu ve bu ortamda tamamen bozunabilmeleri için daha uzun bir zamana ihtiyaç olduğunu göstermektedir.

Keywords

• ASTM 5988
• Polilaktik Asit
• Biyobozunma
• Toprak

References

1. 1. Aframehr, W. M., Molki, B., Heidarian, P., Behzad, T., Sadeghi, M., ve Bagheri, R. (2017) Effect of calcium carbonate nanoparticles on barrier properties and biodegradability of polylactic acid, Fibers and Polymers, 18(11), 2041-2048. doi:10.1007/s12221-017-6853-0
2. 2. Anunciado, M. B., Hayes, D. G., Astner, A. F., Wadsworth, L. C., Cowan-Banker, C. D., Gonzalez, J. E., ve DeBruyn, J. M. (2021) Effect of environmental weathering on biodegradation of biodegradable plastic mulch films under ambient soil and composting conditions. Journal of Polymers and the Environment, 29(9), 2916-2931. doi:10.1007/s10924-021-02088-4
3. 3. ASTM (2018). American Society for Testing and Materials (ASTM) Standard D5988-18. Philadelphia, PA
4. 4. Avérous L. (2008) Polylactic acid: synthesis, properties and applications, Elsevier, Oxford, UK.
5. 5. Boonluksiri, Y., Prapagdee, B., ve Sombatsompop, N. (2021) Promotion of polylactic acid biodegradation by a combined addition of PLA-degrading bacterium and nitrogen source under submerged and soil burial conditions, Polymer Degradation and Stability, 188:109562, doi:10.1016/j.polymdegradstab.2021.109562.
6. 6. Boonmee, C., Kositanont, C., ve Leejarkpai, T. (2016) Degradation of poly (lactic acid) under simulated landfill conditions. Environment and Natural Resources Journal, 14(2), 1-9. doi:10.14456/ennrj.2016.8
7. 7. Briassoulis, D., ve Innocenti, F. D. (2017). Standards for soil biodegradable plastics. In Soil degradable bioplastics for a sustainable modern agriculture (pp. 139-168). Springer, Berlin, Heidelberg. doi:10.1007/978-3-662-54130-2_6
8. 8. Comănită, E. D., Hlihor, R. M., Ghinea, C., ve Gavrilescu, M. (2016) Occurrence of plastic waste in the environment: ecological and health risks. Environmental Engineering & Management Journal (EEMJ), 15(3). doi:10.30638/eemj.2016.073

9. 9. Csikos, A., Faludi, G., Domjan, A., Renner, K., Moczo, J. ve Pukanszky, B. (2015) Modification of interfacial adhesion with a functionalized polymer in PLA/wood composites. European Polymer Journal, 68, 592-600. doi:10.1016/j.eurpolymj.2015.03.032
10. 10. De Jong, S. J., Arias, E. R., Rijkers, D. T. S., Van Nostrum, C. F., Kettenes-Van den Bosch, J. J., ve Hennink, W. E. (2001) New insights into the hydrolytic degradation of poly (lactic acid): participation of the alcohol terminus. Polymer, 42(7), 2795-2802. doi:10.1016/S0032- 3861(00)00646-7
11. 11. Geyer, R., Jambeck, J.R. ve Law, K.L. (2017) Production, use, and fate of all plastics ever made, Science Advances, 3:1–5. doi:10.1126/sciadv.1700782
12. 12. Henton, D. E., Gruber, P., Lunt, J., ve Randall, J. (2005) Polylactic acid technology. In Natural fibers, biopolymers, and biocomposites (pp. 559-607). CRC Press. eBook ISBN:9780429211607
13. 13. Hernández-García, E., Vargas, M., Chiralt, A. ve González-Martínez, C. (2022) Biodegradation of PLA-PHBV Blend Films as Affected by the Incorporation of Different Phenolic Acids. Foods, 11, 243. doi:10.3390/foods11020243
14. 14. Huang, M.-H., Li, S. ve Vert, M. (2004) Synthesis and degradation of PLA-PCL-PLA triblock copolymer prepared by successive polymerization of ε-caprolactone and dl-lactide. Polymer, 45, 8675-8681. doi:10.1016/j.polymer.2004.10.054
15. 15. Ikada, E. (1997) Photo-and bio-degradable polyesters. Photodegradation behaviors of aliphatic polyesters. Journal of Photopolymer Science and Technology, 10(2), 265-270. doi:10.2494/photopolymer.10.265
16. 16. Ingrao, C., Tricase, C., Cholewa-Wójcik, A., Kawecka, A., Rana, R., ve Siracusa, V. (2015) Polylactic acid trays for fresh-food packaging: A Carbon Footprint assessment. Science of the Total Environment, 537, 385-398. doi:10.1016/j.scitotenv.2015.08.023
17. 17. Itävaara, M., Karjomaa, S., ve Selin, J. F. (2002) Biodegradation of polylactide in aerobic an anaerobic thermophilic conditions. Chemosphere, 46(6), 879-885. doi:10.1016/S0045- 6535(01)00163-1
18. 18. Janczak, K., Hrynkiewicz, K., Znajewska, Z., ve Dąbrowska, G. (2018). Use of rhizosphere microorganisms in the biodegradation of PLA and PET polymers in compost soil. International Biodeterioration & Biodegradation, 130, 65-75. doi:10.1016/j.ibiod.2018.03.017
19. 19. Karamanlioglu, M. (2013) Environmental degradation of the compostable plastic packaging material poly (lactic) acid and its impact on fungal communities in compost. The University of Manchester (United Kingdom). https://www.proquest.com/dissertationstheses/ environmental-degradation-compostable-plastic/docview/1775430147/se-2
20. 20. Karamanlioglu, M., ve Robson, G. D. (2013) The influence of biotic and abiotic factors on the rate of degradation of poly (lactic) acid (PLA) coupons buried in compost and soil. Polymer degradation and stability, 98(10), 2063-2071. doi:10.1016/j.polymdegradstab.2013.07.004
21. 21. Karkhanis, S. S. ve Matuana, L. M. (2019) Extrusion blown films of poly(lactic acid) chainextended with food grade multifunctional epoxies, Polymer Engineering & Science, 59, 2211. doi:10.1002/pen.25224
22. 22. Kikkawa, Y., Fujita, M., Abe, H., ve Doi, Y. (2004) Effect of water on the surface molecular mobility of poly (lactide) thin films: an atomic force microscopy study. Biomacromolecules, 5(4), 1187-1193. doi:10.1021/bm0345007
23. 23. Kimura, T., Ishida, Y., Ihara, N. & Saito, Y. (2000). High speed degradation of biodegradable plastics by composting of biological wastes. Biosci. Ind. 57, 35-36. Corpus ID: 138594326
24. 24. Klöpffer, W., ve Grahl, B. (2014) Life cycle assessment (LCA): a guide to best practice. John Wiley & Sons. doi:10.1002/9783527655625
25. 25. Kramschuster, A., ve Turng, L. S. (2010) An injection molding process for manufacturing highly porous and interconnected biodegradable polymer matrices for use as tissue engineering scaffolds. Journal of Biomedical Materials Research Part B: Applied Biomaterials: An Official Journal of The Society for Biomaterials, The Japanese Society for Biomaterials, and The Australian Society for Biomaterials and the Korean Society for Biomaterials, 92(2), 366-376. doi:10.1002/jbm.b.31523
26. 26. Kucharczyk, P., Pavelková, A., Stloukal, P., & Sedlarík, V. (2016). Degradation behaviour of PLA-based polyesterurethanes under abiotic and biotic environments. Polymer Degradation and Stability, 129, 222-230. doi:10.1016/j.polymdegradstab.2016.04.019
27. 27. Lipsa, R., Tudorachi, N., Darie-Nita, R. N., Oprică, L., Vasile, C. ve Chiriac, A. (2016) Biodegradation of poly (lactic acid) and some of its based systems with Trichoderma vi. International journal of biological macromolecules, 88, 515-526. doi:10.1016/j.ijbiomac.2016.04.017
28. 28. Lipsa, R., Tudorachi, N., ve Vasile, C. (2008) Poly (vinyl alcohol)/poly (lactic acid) blends biodegradable films doped with colloidal silver. Revue Roumaine de Chimie, 53(5), 405-413.
29. 29. Lv, S., Zhang, Y., Gu, J., ve Tan, H. (2017) Biodegradation behavior and modelling of soil burial effect on degradation rate of PLA blended with starch and wood flour. Colloids and Surfaces B: Biointerfaces, 159, 800-808. doi:10.1016/j.colsurfb.2017.08.056
30. 30. Mahapatro, A., ve Singh, D. K. (2011) Biodegradable nanoparticles are excellent vehicle for site directed in-vivo delivery of drugs and vaccines. Journal of nanobiotechnology, 9(1), 1- 11. doi:10.1186/1477-3155-9-55
31. 31. Martucci, J. F., ve Ruseckaite, R. A. (2015) Biodegradation behavior of three-layer sheets based on gelatin and poly (lactic acid) buried under indoor soil conditions, Polymer Degradation and Stability, 116, 36-44. doi:10.1016/j.polymdegradstab.2015.03.005
32. 32. Mascheroni, E., Guillard, V., Nalin, F., Mora, L., ve Piergiovanni, L. (2010) Diffusivity of propolis compounds in Polylactic acid polymer for the development of anti-microbial packaging films. Journal of Food Engineering, 98(3), 294-301. doi:10.1016/j.jfoodeng.2009.12.028
33. 33. Ohkita, T., ve Lee, S.H., (2006) Thermal degradation and biodegradability of poly (lacticacid)/corn starch biocomposites. Journal of Applied Polymer Science, 100, 3009–3017. doi:10.1002/app.23425
34. 34. Oliveira, M., Mota, C., Abreu, A. S., ve Nobrega, J. M. (2015) Development of a green material for horticulture. Journal of Polymer Engineering, 35(4), 401-406. doi:10.1515/polyeng-2014-0262
35. 35. Palai, B., Mohanty, S., ve Nayak, S. K. (2021) A comparison on biodegradation behaviour of polylactic acid (PLA) based blown films by incorporating thermoplasticized starch (TPS) and poly (butylene succinate-co-adipate)(PBSA) biopolymer in soil. Journal of Polymers and the Environment, 29(9), 2772-2788. doi:10.1007/s10924-021-02055-z
36. 36. Palsikowski, P. A., Kuchnier, C. N., Pinheiro, I. F., & Morales, A. R. (2018). Biodegradation in soil of PLA/PBAT blends compatibilized with chain extender. Journal of Polymers and the Environment, 26(1), 330-341. doi:10.1007/s10924-017-0951-3
37. 37. Petinakis, E., Liu, X., Yu, L., Way, C., Sangwan, P., Dean, K., Bateman, S. ve Edward, G. (2010) Biodegradation and thermal decomposition of poly(lactic acid)-based materials reinforced by hydrophilic fillers. Polymer Degradation and Stability, 95(9), 1704–1707. doi:10.1016/J.POLYMDEGRADSTAB.2010.05.027
38. 38. Pillin, I., Montrelay, N., Bourmaud, A., ve Grohens, Y. (2008) Effect of thermo-mechanical cycles on the physico-chemical properties of poly (lactic acid). Polymer Degradation and Stability, 93(2), 321-328. doi:10.1016/j.polymdegradstab.2007.12.005
39. 39. Plastics Europe, (2017) An analysis of European plastics production, demand and waste data Plastics – the Facts 2016, Plastics Europe – Association of Plastics Manufacturers. Brussels.
40. 40. Rajesh, G., Prasad, A. R., ve Gupta, A. V. S. S. K. S. (2019). Soil degradation characteristics of short sisal/PLA composites. Materials Today: Proceedings, 18, 1-7. doi:10.1016/j.matpr.2019.06.270
41. 41. Ren, Y., Hu, J., Yang, M., ve Weng, Y. (2019) Biodegradation behavior of poly (lactic acid)(PLA), poly (butylene adipate-co-terephthalate)(PBAT), and their blends under digested sludge conditions, Journal of Polymers and the Environment, 27(12), 2784-2792. doi:10.1007/s10924-019-01563-3
42. 42. Rimoli, M. G., Avallone, L., De Caprariis, P., Galeone, A., Forni, F., ve Vandelli, M. A. (1999) Synthesis and characterisation of poly (d, l-lactic acid)–idoxuridine conjugate. Journal of controlled release, 58(1), 61-68. doi:10.1016/S0168-3659(98)00129-1
43. 43. Rudnik, E., ve Briassoulis, D. (2010) Long-term biodegradability in soil of bio-based biodegradable polymers. In International Conference on Agricultural Engineering-AgEng 2010: towards environmental technologies, Clermont-Ferrand, France, 6-8 September 2010. Cemagref.
44. 44. Rudnik, E., ve Briassoulis, D. (2011) Degradation behaviour of poly(lactic acid) films and fibres in soil under Mediterranean field conditions and laboratory simulations testing, Industrial Crops and Products, 33 (3) 648-658. doi:10.1016/j.indcrop.2010.12.031
45. 45. Saeidlou, S., Huneault, M. A., Li, H., ve Park, C. B. (2012) Poly (lactic acid) crystallization, Progress in Polymer Science, 37(12), 1657-1677. doi:10.1016/j.progpolymsci.2012.07.005
46. 46. Sander, M. (2019) Biodegradation of polymeric mulch films in agricultural soils: concepts, knowledge gaps, and future research directions, Environmental science & technology, 53(5), 2304-2315. doi:10.1021/acs.est.8b05208
47. 47. Sangwan, P. ve Wu, D.Y., (2008) New insights into polylactide biodegradation from molecular ecological techniques. Macromolecular Bioscience, 8, 304-315. doi:10.1002/mabi.200700317
48. 48. Sankauskaitė, A., Stygienė, L., Tumėnienė, M.D., Krauledas, S., Jovaišienė, L. ve Puodžiūnieė, R. (2014) Investigation of cotton component destruction in cotton/polyester blended textile waste materials, Journal of Materials Science, 20, 189-192. doi:10.5755/j01.ms.20.2.3115
49. 49. Schneiderman, D. K. ve Hillmyer, M. A. (2017) 50th Anniversary Perspective: There Is a Great Future in Sustainable Polymers. Macromolecules 50(10): 3733-3749. doi:10.1021/acs.macromol.7b00293
50. 50. Sedničková, M., Pekařová, S., Kucharczyk, P., Bočkaj, J., Janigová, I., Kleinová, A., Jochec- Mošková, D., Omaníková, L., Perďochová, D., Koutný, M., Sedlařík, V., Alexy, P. ve Chodák, I. (2018) Changes of physical properties of PLA-based blends during early stage of biodegradation in compost. International Journal of Biological Macromolecules, 113, 434- 442. doi:10.1016/j.ijbiomac.2018.02.078
51. 51. Shah, A. A., Hasan, F., Hameed, A., ve Ahmed, S. (2008) Biological degradation of plastics: a comprehensive review. Biotechnology advances, 26(3), 246-265. doi:10.1016/j.biotechadv.2007.12.005
52. 52. Shogren, R. L., Doane, W. M., Garlotta, D., Lawton, J. W., ve Willett, J. L. (2003)Biodegradation of starch/polylactic acid/poly (hydroxyester-ether) composite bars in soil. Polymer degradation and stability, 79(3), 405-411. doi:10.1016/S0141-3910(02)00356-7
53. 53. Silva, T. F. D., Menezes, F., Montagna, L. S., Lemes, A. P., ve Passador, F. R. (2019) Effectof lignin as accelerator of the biodegradation process of poly (lactic acid)/lignin composites. Materials Science and Engineering: B, 251, 114441. doi:10.1016/j.mseb.2019.114441
54. 54. Singhvi, M., ve Gokhale, D. (2013) Biomass to biodegradable polymer (PLA). Rsc Advances,3(33), 13558-13568. doi:10.1039/C3RA41592A
55. 55. Spiridon, I., Ursu, R. G., ve Spiridon, I. A. C. (2015) New polylactic acid composites forpackaging applications: Mechanical properties, thermal behavior, and antimicrobial activity. International Journal of Polymer Analysis and Characterization, 20(8), 681-692. doi:10.1080/1023666X.2015.1081131
56. 56. Stloukal, P., Kalendova, A., Mattausch, H., Laske, S., Holzer, C., ve Koutny, M. (2015) The influence of a hydrolysis-inhibiting additive on the degradation and biodegradation of PLA and its nanocomposites. Polymer Testing, 41, 124-132. doi:10.1016/j.polymertesting.2014.10.015
57. 57. Tanjung, F. A., Arifin, Y., ve Husseinsyah, S. (2020) Enzymatic degradation of coconut shell powder–reinforced polylactic acid biocomposites. Journal of Thermoplastic Composite Materials, 33(6), 800-816. doi:10.1177/0892705718811895
58. 58. Tsuji, H., Echizen, Y., ve Nishimura, Y. (2006) Photodegradation of biodegradable polyesters: A comprehensive study on poly (l-lactide) and poly (ɛ-caprolactone). Polymer degradation and stability, 91(5), 1128-1137. doi:10.1016/j.polymdegradstab.2005.07.007
59. 59. Tsuji, H., ve Nakahara, K. (2002) Poly (L‐lactide). IX. Hydrolysis in acid media, Journal of Applied Polymer Science, 86(1), 186-194. doi:10.1002/app.10813
60. 60. Uzun, S. (2020) Farklı azot kaynaklarının topraktaki biyostimülasyon etkilerinin değerlendirilmesi. Bursa Uludağ Üniversitesi, Fen Bilimleri Enstitüsü, Çevre Mühendisliği Anabilim Dalı, Yüksel Lisans Tezi, 74s.
61. 61. Valapaa, R., Pugazhenthi, G. ve Katiyar, V., (2016) Hydrolytic degradation behaviour of sucrose palmitate reinforced poly(lactic acid) nanocomposites. International Journal of Biological Macromolecules, 89, 70–80. doi:10.1016/j.ijbiomac.2016.04.040
62. 62. Vasile, C., Pamfil, D., Râpă, M., Darie-Niţă, R. N., Mitelut, A. C., Popa, E. E., Popescu, P.A., Draghici, M.C., ve Popa, M. E. (2018) Study of the soil burial degradation of some PLA/CS biocomposites. Composites Part B: Engineering, 142, 251-262. doi:10.1016/j.compositesb.2018.01.026
63. 63. Wei, X. F., Bao, R. Y., Cao, Z. Q., Zhang, L. Q., Liu, Z. Y., Yang, W., Xie, B.H. ve Yang, M. B. (2014) Greatly accelerated crystallization of poly (lactic acid): cooperative effect of stereocomplex crystallites and polyethylene glycol. Colloid and Polymer Science, 292(1), 163-172. doi:10.1007/s00396-013-3067-x
64. 64. Weng, Y. X., Jin, Y. J., Meng, Q. Y., Wang, L., Zhang, M., ve Wang, Y. Z. (2013a) Biodegradation behavior of poly (butylene adipate-co-terephthalate) (PBAT), poly (lactic acid)(PLA), and their blend under soil conditions. Polymer Testing, 32(5), 918-926. doi:10.1016/j.polymertesting.2013.05.001
65. 65. Weng, Y. X., Wang, L., Zhang, M., Wang, X. L., ve Wang, Y. Z. (2013b) Biodegradation behavior of P (3HB, 4HB)/PLA blends in real soil environments. Polymer testing, 32(1), 60- 70. doi:10.1016/j.polymertesting.2012.09.014
66. 66. Wesch, C., Bredimus, K., Paulus, M., ve Klein, R. (2016) Towards the suitable monitoring of ingestion of microplastics by marine biota: A review. Environmental pollution, 218, 1200- 1208. doi:10.1016/j.envpol.2016.08.076
67. 67. Wu, Y. L., Wang, H., Qiu, Y. K., ve Loh, X. J. (2016) PLA- based thermogel for the sustained delivery of chemotherapeutics in a mouse model of hepatocellular carcinoma. RSC advances, 6(50), 44506-44513. doi:10.1039/C6RA08022G
68. 68. Zamir, S. S., Fathi, B., Ajji, A., Robert, M., ve Elkoun, S. (2022) Biodegradation of modified starch/poly lactic acid nanocomposite in soil. Polymer Degradation and Stability, 199, 109902. doi:10.1016/j.polymdegradstab.2022.109902
69. 69. Zhang, J., Sato, H., Furukawa, T., Tsuji, H., Noda, I., ve Ozaki, Y. (2006) Crystallization behaviors of poly (3-hydroxybutyrate) and poly (L-lactic acid) in their immiscible and miscible blends. The Journal of Physical Chemistry B, 110(48), 24463-24471. doi:10.1021/jp065233c
70. 70. Zhang, M., Meng, QY, Diao, X.Q. ve Weng, Y.X. (2016) Biodegradation behavior of PLA/PBAT blends. China Plast 30(8):79–86.