Desenvolvimento de compósitos de PCL e pó de madeira
Data
2019-11-20
Autores
Cintra, Sheila Cristina 
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Materiais poliméricos são bastante utilizados em diversos setores devido à sua alta resistência à degradação. A maioria dos polímeros, contudo, são provenientes de fontes não renováveis e podem comprometer o meio ambiente caso seja feito um descarte inadequado. Visando diminuir os impactos ambientais, o presente Trabalho de Conclusão de Curso propôs o desenvolvimento de compósitos a partir de policaprolactona (PCL), um polímero biodegradável, reforçado com pó de
madeira (PM) com teores de 0, 5 e 15% em massa dessa carga natural. Os corpos de prova foram obtidos por meio de uma extrusora de dupla rosca, seguido por prensagem à quente. Foram realizados ensaios de absorção de água, ângulo de contato, envelhecimento em estufa, resistência ao impacto Izod, dureza Shore D e resistência à tração uniaxial. Por fim, foram feitas análises de microscopia eletrônica de varredura (MEV) e calorimetria exploratória diferencial (DSC). Pelos
resultados encontrados, notou-se que é possível desenvolver compósitos a base de PCL e pó madeira como reforço, sem nenhum tratamento superficial a partir de uma extrusora, apresentando grande potencial para substituir polímeros de fontes não renováveis. Observou-se que a presença do reforço contribui na degradação por hidrólise devido ao seu caráter hidrofílico. Conforme o aumento no teor de PM, principalmente para o PCL/15% PM, o material se tornou mais rígido devido ao aumento do módulo elástico correspondente a 61% em relação ao PCL puro. Ao analisar a morfologia dos corpos de prova, os compósitos de PCL com de PM apresentaram, de maneira geral, boa adesão interfacial com a matriz polimérica. Por sua vez, o compósito de PCL com adição de 5% em massa de PM apresentou resultados bastante satisfatórios em relação às propriedades mecânicas e térmicas, com uma boa interação com a matriz de PCL.
Polymers are widely used in various sectors due to their high resistance to degradation. Such polymers, however, are from non-renewable sources and can be environmentally harmful if it is made improper disposal. In order to reduce the environmental impacts, the present work propose the development of composites based on polycaprolactone (PCL), a biodegradable polymer, reinforced with wood powder (WP) with 0, 5 and 15 wt%. The specimens were extruded followed by hot pressing. Water absorption, contact angle, greenhouse aging tests was performed such as Izod impact tests, Shore D hardness, and tensile test. Finally, the analysis of SEM and DSC were carried out. From the results, it is possible to develop composites based on the mixture of PCL and wood powder as natural filler without any surface treatment using an extruder while being capable to achieve the great potential for replacement of polymers from non-renewable sources. It was noticed that the presence of natural filler contributes to degradation by hydrolysis due to its hydrophilic character. As the WP content increases, specially for PCL/15% WP, the samples becomes more rigid due to the elastic modulus increase corresponding to 61% in comparison with the pure PCL. In general, good interfacial adhesion between the polymeric matrix and wood powder was observed. In turn, the PCL/WP composite with the addition of 5 wt% WP presented satisfactory results regarding the mechanical and thermal properties with good interaction between WP and PCL matrix.
Polymers are widely used in various sectors due to their high resistance to degradation. Such polymers, however, are from non-renewable sources and can be environmentally harmful if it is made improper disposal. In order to reduce the environmental impacts, the present work propose the development of composites based on polycaprolactone (PCL), a biodegradable polymer, reinforced with wood powder (WP) with 0, 5 and 15 wt%. The specimens were extruded followed by hot pressing. Water absorption, contact angle, greenhouse aging tests was performed such as Izod impact tests, Shore D hardness, and tensile test. Finally, the analysis of SEM and DSC were carried out. From the results, it is possible to develop composites based on the mixture of PCL and wood powder as natural filler without any surface treatment using an extruder while being capable to achieve the great potential for replacement of polymers from non-renewable sources. It was noticed that the presence of natural filler contributes to degradation by hydrolysis due to its hydrophilic character. As the WP content increases, specially for PCL/15% WP, the samples becomes more rigid due to the elastic modulus increase corresponding to 61% in comparison with the pure PCL. In general, good interfacial adhesion between the polymeric matrix and wood powder was observed. In turn, the PCL/WP composite with the addition of 5 wt% WP presented satisfactory results regarding the mechanical and thermal properties with good interaction between WP and PCL matrix.