resumo
This study explores the valorization of non-commercial chestnut waste from the Portuguese chestnut industry to develop biocomposites. The composites were obtained by hot compression molding, and a Box-Behnken Design model was employed to optimize the mechanical, thermal, and water resistance properties of the chestnut-based composite, using fruit and shell fibers, respectively, as the polymeric matrix and reinforcement agent. The optimal formulation, comprising 70% chestnut, no glycerol, a molding temperature of 120 degrees C, and applying a pressure of 2.93 MPa for 30 min, achieved a Flexural Strength of 9.00 MPa and a Flexural Modulus of 950 MPa. To enhance water resistance, shellac was added as a natural hydrophobic coating. Water interaction tests indicated that shellac-treated biocomposites exhibited superior water resistance, absorbing approximately two times less water than those containing glycerol or untreated samples. Thermal analysis revealed that glycerol acted as a plasticizer, improving flexibility and reducing the glass transition temperature. Additionally, the chestnut-based biocomposite demonstrated an out-of-plane thermal conductivity of 0.79 W/m
palavras-chave
MECHANICAL-PROPERTIES; CHEMICAL-COMPOSITION; SPECTROSCOPY; QUALITY; FIBERS; SHELL
categoria
Polymer Science
autores
Silva, SB; Freitas, OM; Vieira, EF; Gomes, A; Carreiras, AR; Moreira, DC; Esfandiari, P; Silva, JF; Delerue-Matos, C; Domingues, VF
nossos autores
Amália Gomes
Bolseiro de investigaçãoagradecimentos
This work received financial support by Fundacao La Caixa and Ministerio para Ciencia e Tecnologia-Fundacao para a Ciencia e a Tecnologia, through the program Programa Promove. O Futuro do Interior-Valorizacao de residuos solidos do processamento da castanha: extracao de biopolimeros e preparacao de filmes biodegradaveis.