Bio-binders for the improvement of the performance of natural fibers as reinforcements in composites to increase the sustainability in the transport sector

Abstract

In order to reduce the negative impact on the environment of the current composite materials, renewable sources have been used as raw materials. One of the most promising approaches is the substitution of the reinforcement material by natural fibers, which are usually obtained from more sustainable resources (agro-waste). However, these materials have still some limitations and drawbacks for their use in high performance applications, one of the reasons being a poor interaction between fiber and matrix. Recent studies show the possibility of improving their mechanical properties by means of the application of a third material to increase interaction between fiber and matrix. In this paper the use of humins (a by-product of the production of furandicarboxylic acid) has been proved to be an efficient bio-binder for natural fibers and epoxy resin. Bio-composites containing different loadings of humins for large parts for ground transportation applications have been produced by liquid resin infusion, validating the aforementioned approach. The results obtained have demonstrated the feasibility of the strategy of using humins for improving the mechanical properties of bio-composites, accelerating the potential for their market acceptance.