Desenvolvimento de compósitos de ldpe reforçados com fibras de carbono recicladas
Data
2023-06-28
Autores
Seixas, Camila Couto de 
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A constante busca por soluções e/ou formas de reaproveitar os resíduos poliméricos gerados pela população em diversos segmentos a fim de reduzir a poluição e o acúmulo de resíduos do país contribui para a melhoria contínua da tecnologia de reciclagem. As indústrias automobilística e aeronáutica também se incluem neste cenário. Diversos componentes desses setores são constituídos por compósitos de matriz termorrígida com tecido de FC que muitas vezes são descartados e incinerados após o uso. No entanto, esses materiais possuem um alto valor agregado e podem ser reciclados e utilizados como carga reforçante para o desenvolvimento de novos componentes, contribuindo com a economia circular. Neste sentido, o presente trabalho de conclusão de curso busca uma alternativa de reciclagem para compósitos de matriz epóxi com fibra de carbono contínua oriunda da indústria automotiva. Estes compósitos foram moídos utilizando um moinho de facas e peneirados visando a obtenção de cargas de reforço com tamanho homogêneo, por volta de 3,7mm. Para o desenvolvimento de novos materiais foi escolhida como matriz polimérica o polietileno de baixa densidade (LDPE), que possui fácil processabilidade e baixo custo. Compósitos de LDPE com diferentes teores de fibras de carbono recicladas (5, 10, 15 e 20% em massa) foram produzidos por extrusão de dupla rosca e corpos de prova foram moldados por injeção. Os compósitos foram caracterizados por ensaio de tração uniaxial, dureza Shore D, propriedades elétricas, análise reológica e a morfologia foi avaliada por microscopia eletrônica de varredura (MEV). Observou-se um aumento significativo no módulo elástico com o aumento do teor de fibra adicionado, e estas apresentaram-se bem dispersas na matriz polimérica. A composição com adição de 20% em massa de fibra de carbono reciclada obteve um aumento de 433% no módulo elástico comparado ao LDPE. Esses resultados mostram-se promissores para o reuso dos compósitos de epóxi com fibras de carbono podendo ser utilizadas como agentes de reforço para matrizes poliméricas.
The constant search for solutions and/or ways to reuse the polymer waste generated by the population in various sectors in order to reduce pollution and waste accumulation in the country contributes to the continuous improvement of recycling technology. The automotive and aerospace industries are also part of this scenario. Many components in these sectors are made of thermoset matrix composites with carbon fiber fabric, which are often discarded and incinerated after use. However, these materials have high added value and can be recycled and used as reinforcing fillers for the development of new components, contributing to the circular economy. In this context, this undergraduate thesis aims to find a recycling alternative for epoxy matrix composites with continuous carbon fiber from the automotive industry. These composites were ground using a knife mill and sieved to obtain reinforcing fillers with a homogeneous size of approximately 3.7mm. For the development of new materials, low-density polyethylene (LDPE) was chosen as the polymer matrix, which has easy processability and low cost. LDPE composites with different percentages of recycled carbon fibers (5%, 10%, 15%, and 20% by weight) were produced by twin-screw extrusion, and test specimens were molded by injection. The composites were characterized by uniaxial tensile testing, Shore D hardness, electrical properties, rheological analysis, and the morphology was evaluated by scanning electron microscopy (SEM). A significant increase in the elastic modulus was observed with increasing fiber content, and the fibers appeared well dispersed in the polymer matrix. The composition with 20% by weight addition of recycled carbon fiber achieved a 433% increase in the elastic modulus compared to LDPE. These results are promising for the reuse of epoxy composites with carbon fibers, which can be used as reinforcement agents for polymer matrices.
The constant search for solutions and/or ways to reuse the polymer waste generated by the population in various sectors in order to reduce pollution and waste accumulation in the country contributes to the continuous improvement of recycling technology. The automotive and aerospace industries are also part of this scenario. Many components in these sectors are made of thermoset matrix composites with carbon fiber fabric, which are often discarded and incinerated after use. However, these materials have high added value and can be recycled and used as reinforcing fillers for the development of new components, contributing to the circular economy. In this context, this undergraduate thesis aims to find a recycling alternative for epoxy matrix composites with continuous carbon fiber from the automotive industry. These composites were ground using a knife mill and sieved to obtain reinforcing fillers with a homogeneous size of approximately 3.7mm. For the development of new materials, low-density polyethylene (LDPE) was chosen as the polymer matrix, which has easy processability and low cost. LDPE composites with different percentages of recycled carbon fibers (5%, 10%, 15%, and 20% by weight) were produced by twin-screw extrusion, and test specimens were molded by injection. The composites were characterized by uniaxial tensile testing, Shore D hardness, electrical properties, rheological analysis, and the morphology was evaluated by scanning electron microscopy (SEM). A significant increase in the elastic modulus was observed with increasing fiber content, and the fibers appeared well dispersed in the polymer matrix. The composition with 20% by weight addition of recycled carbon fiber achieved a 433% increase in the elastic modulus compared to LDPE. These results are promising for the reuse of epoxy composites with carbon fibers, which can be used as reinforcement agents for polymer matrices.