Hybrid epoxy composites made from treated curauá fibres and organophilic clay

• Published in: Journal of composite materials Vol. 55; no. 1; pp. 57 - 69
• Main Authors: del Pino, Gilberto García, Bezazi, Abderrezak, Boumediri, Haithem, Kieling, Antonio Claudio, Silva, Cláudia Cândida, Dehaini, Jamile, Rivera, Jose Luis Valin, Valenzuela, Maria das Graças da Silva, Díaz, Francisco Rolando Valenzuela, Panzera, Túlio Hallak
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-01-2021
• Subjects: Hybrid composites; organophilic clay; mechanical characterisation; alkali treatment; curauá fibres
• ISSN: 0021-9983; 1530-793X
• DOI: 10.1177/0021998320945785

This work evaluates an epoxy composite reinforced with curauá fibres and/or organophilic clay. Epoxy polymers reinforced with nano-clays are also assessed. Composites are manufactured by cold pressing using fibres in pristine and treated conditions. Three levels of the factors NaOH solution (2.5, 5 and 10%) and immersion time (2, 4 and 10 hours) are investigated. Nano-clays are incorporated at the levels of 2.5, 5 and 10 wt.%. The morphology and crystallinity of the treated fibres are evaluated by scanning electron microscopy and X-ray diffraction, respectively. Tensile, three-point bending and impact tests are performed to characterise the composites. Tensile strength, flexural strength and impact resistance are increased by 24%, 44% and 47%, respectively, when compared to untreated fibre composites. The highest tensile and flexural strengths are achieved by hybrid composites containing 5 wt.% of nano-clay and 20 wt.% of curauá fibres treated with 5% NaOH for 4 hours. In contrast, the highest tensile modulus is achieved when hybrid composites are made from untreated fibres and 10 wt.% of nanoparticles. The highest impact resistance is obtained by curauá composites, without particles, composed of fibres treated with 5% NaOH for 4 hours. The inclusion of nano-clay leads to reduced impact resistance values.