Preparo e caracterização das propriedades de misturas ternárias de PLA/PBAT/NBR

• Ano de defesa: 2018
• Autor(a) principal: Fernandes, Teresa Maria Dias
• Orientador(a): Leite, Marcia Christina Amorim Moreira
• Banca de defesa: Furtado, Cristina Russi Guimarães , Silva, Ana Lúcia Nazareth da , Novack, Kátia Monteiro , Costa, Antonio Carlos Augusto da
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade do Estado do Rio de Janeiro
• Programa de Pós-Graduação: Programa de Pós-Graduação em Química
• Departamento: Centro de Tecnologia e Ciências::Instituto de Química
• País: BR
• Palavras-chave em Português: Poli(ácido lático); poli(adipato-co-tereftalato de butileno); borracha nitrílica; tenacificação; cinética de degradação; Biodegradação anaeróbia
• Palavras-chave em Inglês: Poly(lactic acid); poly(butylene-adipate-co-terephtalate); nitrile rubber; improvement in the toughness; degradation kinetic; anaerobic biodegradation
• Área do conhecimento CNPq: CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA::QUIMICA ORGANICA::POLIMEROS E COLOIDES
• Link de acesso: http://www.bdtd.uerj.br/handle/1/15646

The elaboration of new polymeric blends presents itself as an alternative to produce new materials with properties that are adequate for specific purposes. Considering the last decades' growing concern with the environment and the production of non-petroleum based materials, the poly(lactic acid) PLA, elaborated from carbohydrates, has been receiving special attention. However, the use of PLA, a fragile fracture polymer, presents restrictions due to its low impact resistance. PLA properties are being improved through the production of blends with other polymers, most of them being thermoplastics, seeking to boost its usability, such as is the case with its commercial blend, poly(butylene-adipate-co-terephtalate) (PBAT). This study analyzed the thermomechanical behavior of the blends created through the incorporation of the acrylonitrile-butadiene copolymer (nitrile rubber or NBR), in various concentrations, to a commercial blend of PLA/PBAT containing 70% of PLA, seeking to increase its tenacity. The blends were made via extrusion processes and were characterized by scanning electron microscopy techniques, thermal analyses, rheology and mechanical properties. The determination of the biochemical methane potential was also carried through in order to evaluate its biodegradability in anaerobic environment. The results have shown that NBR concentrations of 10 and 20% have increased the PLA/PBAT blend's tenacity significantly, causing a slight variation in the activation energy for 5% of PLA amount degradation in each blend, and leading to a decrease in its service life. The ternary blend has demonstrated less biodegradability in mesophylic anaerobic systems than the original commercial blend, but the results of the study show the system still presents biodegradability characteristics, allowing for its application in the plastic packaging sector.