Structure versus Property Relationship of Hybrid Silk/Flax Composites

Abstract

The increasing demand for environmental and sustainable materials has motivated efforts to fabricate biocomposites as alternatives to conventional synthetic fiber composites. However, biocomposite materials have some drawbacks such as poor mechanical resistance, fiber/matrix incompatibility, low thermal resistance and high moisture absorption. Extensive research has been conducted to address these challenges, in terms of the sustainable production, serviceability, reliability and properties of these novel biocomposites. Silk fibers have excellent biocompatibility and biodegradability along with moderate mechanical properties, while flax fibers have a high specific strength and modulus. The combination of the silk fiber with moderate modulus and stiffness with flax fibers with high specific strength and modulus allows the modulation of the properties of silk using the intra- and inter-hybridization of both fibers. In this study, silk and flax fibers are combined in different arrangements, totaling eight different composites; the quasi-static mechanical properties and dynamic mechanical thermal analysis are discussed, focusing on the structure versus relationship properties, with the aim of corroborating the freely available data from literature. The main findings indicated that the synergic effect of the flax fiber and silk fiber leads to a tailormade composite with a low cost and high performance.