COMPÓSITOS BIODEGRADÁVEIS DE BAGAÇO DE CANA DE AÇÚCAR E POLIURETANO VEGETAL PARA APLICAÇÕES BIOMÉDICAS
BIODEGRADABLE COMPOSITES OF SUGARCANE BAGASSE AND VEGETAL POLYURETHANE FOR BIOMEDICAL APPLICATIONS
DOI:
https://doi.org/10.18066/revistaunivap.v30i67.4515
Abstract
Due to the environmental problems caused by polymers, it is desirable to use biodegradable biopolymers such as vegetable polyurethane and sugar cane bagasse fibers. Therefore, the work aimed at the development of biodegradable biocomposites of sugarcane bagasse fibers for application in orthoses and evaluated their viability through mechanical, chemical, biodegradation and computational simulation tests. It was possible to obtain PU composites with sugarcane bagasse, which showed good interaction through the analysis of scanning electron microscopy images. It was observed that the addition of sugar cane bagasse fibers to the PU increased impact resistance, Young's modulus, there was a decrease in elongation and hardness and that the addition of fibers maintained the maximum tension value. The water absorption test showed that the fibers increased water absorption and biodegradation compared to polyurethane, which is advantageous for the orthosis, as it causes less accumulation of water between the patient's skin and the orthosis and reduces problems of infections and wounds. The computational simulation showed that it would be possible to make an orthosis with the PU composite with sugarcane bagasse and that for that it would be necessary to optimize the design of the orthosis. The use of PU composite with sugarcane bagasse in the medical field is promising, as it is a non-toxic material, from a renewable source and that uses agro-industrial waste with low added value, also presenting the advantage of providing better comfort to the patient
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References
Alokika, A., Kumar, A., Kumar, V., & Singh, B. (2021). Cellulosic and hemicellulosic fractions of sugarcane bagasse: Potential, challenges and future perspective. International Journal of Biological Macromolecules, 169, 564–582. https://doi.org/10.1016/j.ijbiomac.2020.12.175
Cao, Y., Shibata, S., & Fukumoto, I. (2006). Mechanical properties of biodegradable composites reinforced with bagasse fibre before and after alkali treatments. Composites Part A: Applied Science and Manufacturing, 37(3), 423–429. https://doi.org/10.1016/j.compositesa.2005.05.045
Chaudhary, V., Tomar, A., Sindhu, A., Choudhary, D., & Kumar, M. (2021). Valorisation and significance of sugarcane bagasse: A review. International Journal of Agricultural and Statistical Sciences, 17(1), 1071–1078. https://connectjournals.com/03899.2021.17.1071
D’Almeida, J. R. M; Calado, V.; Barreto, D. W.; & d’Almeida, Jr. R. M., (2005). Acetilação da Fibra de Bucha (Luffa cylindrica). Polímeros: Ciência e Tecnologia, 15(1), 59-62. http://dx.doi.org/10.1590/S0104-14282005000100013
DeZeeuw, K. G., & Dudek, N. (2019). Orthosis Comfort Score: Establishing initial evidence of reliability and validity in ankle foot orthosis users. Prosthetics & Orthotics International, 43(5), 478–484. https://doi.org/10.1177/0309364619866611
Dos Santos, B. H., De Souza Do Prado, K., Jacinto, A. A., & Da Silva Spinacé, M. A. (2018). Influence of Sugarcane Bagasse Fiber Size on Biodegradable Composites of Thermoplastic Starch. Journal of Renewable Materials, 6(2), 176–182. https://doi.org/10.7569/JRM.2018.634101
Ferreira, F. V., Trindade, G. N., Lona, L. M. F., Bernardes, J. S., & Gouveia, R. F. (2019). LDPE-based composites reinforced with surface modified cellulose fibres: 3D morphological and morphometrical analyses to understand the improved mechanical performance. European Polymer Journal, 117, 105–113. https://doi.org/10.1016/j.eurpolymj.2019.05.005
Fiorentino, A., Ginestra, P. S & Ceretti, E. (2016). Potential of modeling and simulations of bioengineered devices: Endoprostheses, prostheses and orthoses. Engineering in Medicine 230(7), 607-638. https://doi.org/10.1177/0954411916643343
Gallos, A., Paës, G., Allais, F., & Beaugrand, J. (2017). Lignocellulosic fibers: A critical review of the extrusion process for enhancement of the properties of natural fiber composites. RSC Advances, 7(55), 34638–34654. https://doi.org/10.1039/C7RA05240E
Geyer, R., Jambeck, J. R., & Law, L. (2017) Production, use, and fate of all plastics ever made. Science Advances, 7, (1-5) https://doi.org/10.1126/sciadv.1700782
Jacinto, A. A., & Spinacé, A. S. M. (2019). Mapping of the Brazilian Groups Studying Nanocellulose. Journal of renewable materials, 7(5), 429-440 https://doi.org/10.32604/jrm.2019.04427
John, M., & Thomas, S. (2008). Biofibres and biocomposites. Carbohydrate Polymers, 71(3), 343–364. https://doi.org/10.1016/j.carbpol.2007.05.040
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
Kale, S. K., Deshmukh, A. G., Dudhare, M. S., & Patil, V. B. (2015). Microbial degradation of plastic: a review. Journal of Biochemical Technology, 6(2), 952-961.
Kessler, M. R., Zhang, C., & Madbouly, S. A. (2015). Biobased Polyurethanes Prepared from Different Vegetable Oils. ACS Applied Materials & Interfaces, 7, 1226−1233. https://doi.org/10.1021/am5071333
Miléo, P. C., Oliveira, M. F., Luz, S. M., Rocha, G. J. M., & Gonçalves, A. R. (2016). Thermal and chemical characterization of sugarcane bagasse cellulose/lignin-reinforced composites. Polymer Bulletin, 73, 3163–3174. https://doi.org/10.1007/s00289-016-1647-x
Moghaddam L.; Naureen, B.; Haseeb, A. S. M. A.; Basirun, W. J., & Muhamad, F. (2022). Production of rigid bio-based polyurethane foams from sugarcane bagasse. Industrial Crops & Products 188, 1-15. https://doi.org/10.1016/j.indcrop.2022.115578
Naureen, B., Haseeb, A. S. M. A., Basirun, W. J., & Muhamad, F. (2021). Recent advances in tissue engineering scaffolds based on polyurethane and modified polyurethane. Materials Science and Engineering: C, 118, 111228. https://doi.org/10.1016/j.msec.2020.111228
Oushabi, A. (2019). The pull-out behavior of chemically treated lignocellulosic fibers/polymeric matrix interface (LF/PM): A review. Composites Part B: Engineering, 174(1) 107059. http://dx.doi.org/10.1016/j.compositesb.2019.107059
Pedersen, D. D., Kim, S., & Wagner, W. R. (2022). Biodegradable polyurethane scaffolds in regenerative medicine: Clinical translation review. Journal of Biomedical Materials Research Part A, 110(8), 1460–1487. https://doi.org/10.1002/jbm.a.37394https://doi.org/10.1002/jbm.a.37394
Petrović, Z. S., Xu, Y., Milić, J., Glenn, G., & Klamczynski, A. (2010). Biodegradation of thermoplastic polyurethanes from vegetable oils. Journal of Polymers and the Environment, 18, 94-97. https://doi.org/10.1007/s10924-010-0194-z
Rajput, B. S., Hai, T. A. P., Gunawan, N. R., Tessman, M., Neelakantan, N., Scofield, G. B., Brizuela, J., Samoylov, A. A., Modi, M., Shepherd, J., Patel, A., Pomeroy, R. S., Pourahmady, N., Mayfield, S. P., & Burkart, M. D. (2022). Renewable low viscosity polyester‐polyols for biodegradable thermoplastic polyurethanes. Journal of Applied Polymer Science, 139(43), e53062. https://doi.org/10.1002/app.53062
Rosa, D. S, & Guedes, C. G. F. (2003). Desenvolvimento de processo de reciclagem de resíduos industriais de poliuretano e caracterização dos produtos obtidos. Polymers, 13(1), 64-71. http://dx.doi.org/10.1590/S0104-14282003000100012
Sabnis, A. S, & Kaikade, D. S. (2023a) Polyurethane foams from vegetable oil‑based polyols: a review. Polymer Bulletin, 80, 2239–2261. https://doi.org/10.1007/s00289-022-04155-9
Sabnis, A. S, & Kaikade, D. S. (2023b). Recent Advances in Polyurethane Coatings and Adhesives Derived from Vegetable Oil‑Based Polyols. Journal of Polymers and the Environment, 1, 1-23. https://doi.org/10.1007/s10924-023-02920-z
Santos, J. V. G. D., Pereira, M. A. D. R., Medola, F. O., & Paschoarelli, L. C. (2018). Design sustentável aplicado ao projeto de produtos assistivos (proteses) fabricados com biocompósitos. In A. J. V. Arruda, Design, Artefatos e Sistema Sustentável (p. 333–350). Editora Blucher. https://doi.org/10.5151/9788580392982-17
Sawpan, M. A. (2018). Polyurethanes from vegetable oils and applications: a review. Journal of Polymer Research, 25(184), 1-15. https://doi.org/10.1007/s10965-018-1578-3
Shahar, F. S., Hameed Sultan, M. T., Lee, S. H., Jawaid, M., Md Shah, A. U., Safri, S. N. A., & Sivasankaran, P. N. (2019). A review on the orthotics and prosthetics and the potential of kenaf composites as alternative materials for ankle-foot orthosis. Journal of the Mechanical Behavior of Biomedical Materials, 99, 169–185. https://doi.org/10.1016/j.jmbbm.2019.07.020
Spinacé, M. A. S., & Santos T. A. (2021). Sandwich panel biocomposite of thermoplastic corn starch and bacterial cellulose. International Journal of Biological Macromolecules, 167(15), 358-368. https://doi.org/10.1016/j.ijbiomac.2020.11.156
Sukyai, P., Torgbo, S., & Quan, V. M. (2021). Cellulosic value-added products from sugarcane bagasse. Cellulose, 28, 5219-5240. https://doi.org/10.1007/s10570-021-03918-
Tita, S. P. S., Paiva, J. M. F., & Frollini, E. (2002). Resistência ao Impacto e Outras Propriedades de Compósitos Lignocelulósicos: Matrizes Termofixas Fenólicas Reforçadas com Fibras de Bagaço de Cana-de-açúcar. Polymers: Science and Technology, 12(4), 228-239. http://dx.doi.org/10.1590/S0104-14282002000400005
Tran, H. T. T., Deshan, A. D. K., Doherty, W., Rackemann, D., & Moghaddam, L. (2022). Production of rigid bio-based polyurethane foams from sugarcane bagasse. Industrial Crops and Products, 188, 115578. https://doi.org/10.1016/j.indcrop.2022.115578
Uscátegui, Y. L., Arévalo, F. R., Díaz, L. E., Cobo, M. I., & Valero, M. F. (2016). Microbial degradation, cytotoxicity and antibacterial activity of polyurethanes based on modified castor oil and polycaprolactone. Journal of Biomaterials Science, Polymer Edition, 27(18), 1860-1879. https://doi.org/10.1080/09205063.2016.1239948
Valero, M. F., Uscátegui, Y. L., & Díaz, L. E. (2018) Aplicaciones Biomédicas de Poliuretanos, Química Nova, 41(4), 434-445. http://dx.doi.org/10.21577/0100-4042.20170191
Yin, G-Z., & Yang, X-M. (2020) Biodegradable polymers: a cure for the planet, but a long way to go. Journal of Polymer Research, 27(2), 27-38. https://doi.org/10.1007/s10965-020-2004-1
Yu, Z., Xiao, Y., Tian, H., Liu, S., Zeng, J., & Luo, X. (2019). Bagasse as functional fillers to improve and control biodegradability of soy oil-based rigid polyurethane foams. Korean Journal of Chemical Engineering, 36(10), 1740–1745. https://doi.org/10.1007/s11814-019-0349-0
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2024-11-11
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Angelica dos Santos, T., Molina Satirio, C., Oliveira Fernandes da Silva, K., Virgem Carvalho de Paula, M., & Francisco de Paula, N. (2024). BIODEGRADABLE COMPOSITES OF SUGARCANE BAGASSE AND VEGETAL POLYURETHANE FOR BIOMEDICAL APPLICATIONS. Revista Univap, 30(67). https://doi.org/10.18066/revistaunivap.v30i67.4515
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Copyright (c) 2024 Revista Univap
This work is licensed under a Creative Commons Attribution 4.0 International License.
This work is licensed under a Creative Commons Attribution 4.0 International.
This license allows others to distribute, remix, tweak, and build upon your work, even commercially, as long as they credit you for the original creation.
http://creativecommons.org/licenses/by/4.0/legalcode
DOI:
https://doi.org/10.18066/revistaunivap.v30i67.4515Abstract
Due to the environmental problems caused by polymers, it is desirable to use biodegradable biopolymers such as vegetable polyurethane and sugar cane bagasse fibers. Therefore, the work aimed at the development of biodegradable biocomposites of sugarcane bagasse fibers for application in orthoses and evaluated their viability through mechanical, chemical, biodegradation and computational simulation tests. It was possible to obtain PU composites with sugarcane bagasse, which showed good interaction through the analysis of scanning electron microscopy images. It was observed that the addition of sugar cane bagasse fibers to the PU increased impact resistance, Young's modulus, there was a decrease in elongation and hardness and that the addition of fibers maintained the maximum tension value. The water absorption test showed that the fibers increased water absorption and biodegradation compared to polyurethane, which is advantageous for the orthosis, as it causes less accumulation of water between the patient's skin and the orthosis and reduces problems of infections and wounds. The computational simulation showed that it would be possible to make an orthosis with the PU composite with sugarcane bagasse and that for that it would be necessary to optimize the design of the orthosis. The use of PU composite with sugarcane bagasse in the medical field is promising, as it is a non-toxic material, from a renewable source and that uses agro-industrial waste with low added value, also presenting the advantage of providing better comfort to the patient
Downloads
References
Alokika, A., Kumar, A., Kumar, V., & Singh, B. (2021). Cellulosic and hemicellulosic fractions of sugarcane bagasse: Potential, challenges and future perspective. International Journal of Biological Macromolecules, 169, 564–582. https://doi.org/10.1016/j.ijbiomac.2020.12.175
Cao, Y., Shibata, S., & Fukumoto, I. (2006). Mechanical properties of biodegradable composites reinforced with bagasse fibre before and after alkali treatments. Composites Part A: Applied Science and Manufacturing, 37(3), 423–429. https://doi.org/10.1016/j.compositesa.2005.05.045
Chaudhary, V., Tomar, A., Sindhu, A., Choudhary, D., & Kumar, M. (2021). Valorisation and significance of sugarcane bagasse: A review. International Journal of Agricultural and Statistical Sciences, 17(1), 1071–1078. https://connectjournals.com/03899.2021.17.1071
D’Almeida, J. R. M; Calado, V.; Barreto, D. W.; & d’Almeida, Jr. R. M., (2005). Acetilação da Fibra de Bucha (Luffa cylindrica). Polímeros: Ciência e Tecnologia, 15(1), 59-62. http://dx.doi.org/10.1590/S0104-14282005000100013
DeZeeuw, K. G., & Dudek, N. (2019). Orthosis Comfort Score: Establishing initial evidence of reliability and validity in ankle foot orthosis users. Prosthetics & Orthotics International, 43(5), 478–484. https://doi.org/10.1177/0309364619866611
Dos Santos, B. H., De Souza Do Prado, K., Jacinto, A. A., & Da Silva Spinacé, M. A. (2018). Influence of Sugarcane Bagasse Fiber Size on Biodegradable Composites of Thermoplastic Starch. Journal of Renewable Materials, 6(2), 176–182. https://doi.org/10.7569/JRM.2018.634101
Ferreira, F. V., Trindade, G. N., Lona, L. M. F., Bernardes, J. S., & Gouveia, R. F. (2019). LDPE-based composites reinforced with surface modified cellulose fibres: 3D morphological and morphometrical analyses to understand the improved mechanical performance. European Polymer Journal, 117, 105–113. https://doi.org/10.1016/j.eurpolymj.2019.05.005
Fiorentino, A., Ginestra, P. S & Ceretti, E. (2016). Potential of modeling and simulations of bioengineered devices: Endoprostheses, prostheses and orthoses. Engineering in Medicine 230(7), 607-638. https://doi.org/10.1177/0954411916643343
Gallos, A., Paës, G., Allais, F., & Beaugrand, J. (2017). Lignocellulosic fibers: A critical review of the extrusion process for enhancement of the properties of natural fiber composites. RSC Advances, 7(55), 34638–34654. https://doi.org/10.1039/C7RA05240E
Geyer, R., Jambeck, J. R., & Law, L. (2017) Production, use, and fate of all plastics ever made. Science Advances, 7, (1-5) https://doi.org/10.1126/sciadv.1700782
Jacinto, A. A., & Spinacé, A. S. M. (2019). Mapping of the Brazilian Groups Studying Nanocellulose. Journal of renewable materials, 7(5), 429-440 https://doi.org/10.32604/jrm.2019.04427
John, M., & Thomas, S. (2008). Biofibres and biocomposites. Carbohydrate Polymers, 71(3), 343–364. https://doi.org/10.1016/j.carbpol.2007.05.040
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
Kale, S. K., Deshmukh, A. G., Dudhare, M. S., & Patil, V. B. (2015). Microbial degradation of plastic: a review. Journal of Biochemical Technology, 6(2), 952-961.
Kessler, M. R., Zhang, C., & Madbouly, S. A. (2015). Biobased Polyurethanes Prepared from Different Vegetable Oils. ACS Applied Materials & Interfaces, 7, 1226−1233. https://doi.org/10.1021/am5071333
Miléo, P. C., Oliveira, M. F., Luz, S. M., Rocha, G. J. M., & Gonçalves, A. R. (2016). Thermal and chemical characterization of sugarcane bagasse cellulose/lignin-reinforced composites. Polymer Bulletin, 73, 3163–3174. https://doi.org/10.1007/s00289-016-1647-x
Moghaddam L.; Naureen, B.; Haseeb, A. S. M. A.; Basirun, W. J., & Muhamad, F. (2022). Production of rigid bio-based polyurethane foams from sugarcane bagasse. Industrial Crops & Products 188, 1-15. https://doi.org/10.1016/j.indcrop.2022.115578
Naureen, B., Haseeb, A. S. M. A., Basirun, W. J., & Muhamad, F. (2021). Recent advances in tissue engineering scaffolds based on polyurethane and modified polyurethane. Materials Science and Engineering: C, 118, 111228. https://doi.org/10.1016/j.msec.2020.111228
Oushabi, A. (2019). The pull-out behavior of chemically treated lignocellulosic fibers/polymeric matrix interface (LF/PM): A review. Composites Part B: Engineering, 174(1) 107059. http://dx.doi.org/10.1016/j.compositesb.2019.107059
Pedersen, D. D., Kim, S., & Wagner, W. R. (2022). Biodegradable polyurethane scaffolds in regenerative medicine: Clinical translation review. Journal of Biomedical Materials Research Part A, 110(8), 1460–1487. https://doi.org/10.1002/jbm.a.37394https://doi.org/10.1002/jbm.a.37394
Petrović, Z. S., Xu, Y., Milić, J., Glenn, G., & Klamczynski, A. (2010). Biodegradation of thermoplastic polyurethanes from vegetable oils. Journal of Polymers and the Environment, 18, 94-97. https://doi.org/10.1007/s10924-010-0194-z
Rajput, B. S., Hai, T. A. P., Gunawan, N. R., Tessman, M., Neelakantan, N., Scofield, G. B., Brizuela, J., Samoylov, A. A., Modi, M., Shepherd, J., Patel, A., Pomeroy, R. S., Pourahmady, N., Mayfield, S. P., & Burkart, M. D. (2022). Renewable low viscosity polyester‐polyols for biodegradable thermoplastic polyurethanes. Journal of Applied Polymer Science, 139(43), e53062. https://doi.org/10.1002/app.53062
Rosa, D. S, & Guedes, C. G. F. (2003). Desenvolvimento de processo de reciclagem de resíduos industriais de poliuretano e caracterização dos produtos obtidos. Polymers, 13(1), 64-71. http://dx.doi.org/10.1590/S0104-14282003000100012
Sabnis, A. S, & Kaikade, D. S. (2023a) Polyurethane foams from vegetable oil‑based polyols: a review. Polymer Bulletin, 80, 2239–2261. https://doi.org/10.1007/s00289-022-04155-9
Sabnis, A. S, & Kaikade, D. S. (2023b). Recent Advances in Polyurethane Coatings and Adhesives Derived from Vegetable Oil‑Based Polyols. Journal of Polymers and the Environment, 1, 1-23. https://doi.org/10.1007/s10924-023-02920-z
Santos, J. V. G. D., Pereira, M. A. D. R., Medola, F. O., & Paschoarelli, L. C. (2018). Design sustentável aplicado ao projeto de produtos assistivos (proteses) fabricados com biocompósitos. In A. J. V. Arruda, Design, Artefatos e Sistema Sustentável (p. 333–350). Editora Blucher. https://doi.org/10.5151/9788580392982-17
Sawpan, M. A. (2018). Polyurethanes from vegetable oils and applications: a review. Journal of Polymer Research, 25(184), 1-15. https://doi.org/10.1007/s10965-018-1578-3
Shahar, F. S., Hameed Sultan, M. T., Lee, S. H., Jawaid, M., Md Shah, A. U., Safri, S. N. A., & Sivasankaran, P. N. (2019). A review on the orthotics and prosthetics and the potential of kenaf composites as alternative materials for ankle-foot orthosis. Journal of the Mechanical Behavior of Biomedical Materials, 99, 169–185. https://doi.org/10.1016/j.jmbbm.2019.07.020
Spinacé, M. A. S., & Santos T. A. (2021). Sandwich panel biocomposite of thermoplastic corn starch and bacterial cellulose. International Journal of Biological Macromolecules, 167(15), 358-368. https://doi.org/10.1016/j.ijbiomac.2020.11.156
Sukyai, P., Torgbo, S., & Quan, V. M. (2021). Cellulosic value-added products from sugarcane bagasse. Cellulose, 28, 5219-5240. https://doi.org/10.1007/s10570-021-03918-
Tita, S. P. S., Paiva, J. M. F., & Frollini, E. (2002). Resistência ao Impacto e Outras Propriedades de Compósitos Lignocelulósicos: Matrizes Termofixas Fenólicas Reforçadas com Fibras de Bagaço de Cana-de-açúcar. Polymers: Science and Technology, 12(4), 228-239. http://dx.doi.org/10.1590/S0104-14282002000400005
Tran, H. T. T., Deshan, A. D. K., Doherty, W., Rackemann, D., & Moghaddam, L. (2022). Production of rigid bio-based polyurethane foams from sugarcane bagasse. Industrial Crops and Products, 188, 115578. https://doi.org/10.1016/j.indcrop.2022.115578
Uscátegui, Y. L., Arévalo, F. R., Díaz, L. E., Cobo, M. I., & Valero, M. F. (2016). Microbial degradation, cytotoxicity and antibacterial activity of polyurethanes based on modified castor oil and polycaprolactone. Journal of Biomaterials Science, Polymer Edition, 27(18), 1860-1879. https://doi.org/10.1080/09205063.2016.1239948
Valero, M. F., Uscátegui, Y. L., & Díaz, L. E. (2018) Aplicaciones Biomédicas de Poliuretanos, Química Nova, 41(4), 434-445. http://dx.doi.org/10.21577/0100-4042.20170191
Yin, G-Z., & Yang, X-M. (2020) Biodegradable polymers: a cure for the planet, but a long way to go. Journal of Polymer Research, 27(2), 27-38. https://doi.org/10.1007/s10965-020-2004-1
Yu, Z., Xiao, Y., Tian, H., Liu, S., Zeng, J., & Luo, X. (2019). Bagasse as functional fillers to improve and control biodegradability of soy oil-based rigid polyurethane foams. Korean Journal of Chemical Engineering, 36(10), 1740–1745. https://doi.org/10.1007/s11814-019-0349-0
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Copyright (c) 2024 Revista Univap
This work is licensed under a Creative Commons Attribution 4.0 International License.
This work is licensed under a Creative Commons Attribution 4.0 International.
This license allows others to distribute, remix, tweak, and build upon your work, even commercially, as long as they credit you for the original creation.
http://creativecommons.org/licenses/by/4.0/legalcode
