Processing and properties of EVOH film reinforced with lignocellulosic fillers

Abstract

Due to advantages such as low cost, lightweight, possibility of environmental protection and good mechanical properties when compared with fiberglass reinforcement materials, composites reinforced with natural fibers have been investigated several times. This kind of reinforcement is an option to improve polymers and increase the fields of applications of polymeric composite materials. In the present investigation, the changes in mechanical and morphological properties of flexible composite film obtained by the incorporation of lignocellulosic fillers in ethylene–vinyl alcohol copolymer (EVOH) were investigated. EVOH with 32 mol % ethylene was used as the matrix and piassava (Attalea funifera Mart) fiber residues disposed by the transformation industries and reduced to fine powder was used as reinforcing filler to prepare the flexible composite film. EVOH/Piassava composite film was prepared by melt extrusion, using a twin screw extruder machine and blown extrusion process. The flexible EVOH and composite film samples obtained were characterized by mechanical properties, SEM and XRD analysis and the correlation between their properties were discussed. The mechanical results showed an increase of around 30 % in tensile strength at break of neat EVOH due to piassava fiber addition, even though, there isn’t a very good interfacial adhesion between piassava fiber and EVOH. It results suggest that the gain in mechanical properties can be superior if a compatibilizing or cross-linking agents is added in composite and lead to obtaining strong interface adhesion between piassava fibers and EVOH resin.