Eco-composites based on biodegradable polyester: chemical modification and plasma treatment of hemp fiber reinforcement

The present contribution focus on eco-composites based on a commercial bio-polyester (PBAT) and high amounts of raw HFs. To promote the adhesion between the polyester matrix and the fibrous reinforcement, the fiber surface was treated with suitable coupling agents. Two different experimental strategies were explored: i) chemical modification of HFs by using PBAT macrocyclic oligomers (MCOs) as the coupling agent [1]; and ii) plasma treatment through a novel soft plasma jet device (developed by Nadir SrL) contemporary able to activate the fiber surface and deposit on it reactive monomers, such as methyl methacrylate (MMA), (3-aminopropyl)triethoxysilane (APTES), and (3-glycidyloxypropyl)trimethoxysilane (GLYMO). Unmodified and surface modified fibers were characterized and compared in terms of thermal behavior and morphological features. Long-fiber eco-composites were then prepared by a suitable compression molding procedure and characterized by thermal, morphological and dynamic-mechanical analysis.