Influence of acetosolv and eco-friendly bleaching treatment of orange bagasse in biocomposites properties: A mechanical and thermal approach

Abstract

Abstract The development of efficient pre-treatments is widely used in biobased products to add value to the residue. For that purpose, this work aims to carry out fibers chemically extracted from the orange bagasse (Citrus sinensis) as reinforcement in polymeric matrix composites. The fibers were extracted by acetosolv, following two bleaching steps, to obtain fibers with properties that promote their use in polymer matrix composites. Orange bagasse untreated (OBU), orange bagasse untreated_acetosolv (OBAc), and acetosolv_bleaching (OBAc-B) were characterized by chemical composition, thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR). Biocomposites were prepared using a HIPS matrix with 15% reinforcement and chemically extracted orange bagasse fibers (OBU, OBAc, OBAc-B). XRD data showed that the OBAc-B has higher crystallinity indexes than OBU (15.1 to 48.3% OBAc-B). Mechanical behavior of composites OBU, OBAc, and OBAc-B present an oscillation on tensile, modulus, and strain as a function of the most appropriate reinforcement treatment (i.e., acetosolv without bleaching). Results indicate that all treatment factors used in this work are influential in the fiber mechanical, chemical, and thermal characteristics, as a promising approach to extract cellulose fibers from OBU and use them as a reinforcement for polymer matrix application.