Production and characterization of natural waste reinforced biobased polymer composites

Although commercial epoxy resin has a wide global market potential such as aerospace, automotive, wind energy, composite materials, paints and coatings, its content of bisphenol-A (BPA), an endocrine disruptor, encourages researchers to produce biobased epoxy for human health and environmental reasons. In this thesis, fueled by this motivation, a biobased epoxy resin (EIA) was produced through the esterification reaction between biobased itaconic acid (IA) and epichlorohydrin (ECH). The chemical structure of EIA was confirmed by FT-IR and 1H NMR analyses. Olive pomace waste (PW) has been evaluated for its potential as a supplement, biodegradability and cost-saving properties. Chemical modification was carried out with sodium hydroxide (NaOH) to improve the surface properties of the natural waste reinforcement material. Neat-PW and NaOH modified PW (NaOH-PW) was used as a cheap reinforcement material in the bisphenol A type epoxy resin (ER)-EIA mixture matrix system. This study emphasized the effect of modified ER system and reinforcement elements on composite materials. Reinforcements were characterized using FT-IR, FE-SEM/EDX and particle size analysis, while composites were characterized using TGA, SEM, water retention and contact angle measurement (C.A.) and mechanical tests. Morphological results showed an increase in adhesion between alkaline modified PW fillers and the ER-EIA matrix. NaOH-PW composites exhibited higher tensile strength compared to both pure ER-EIA and virgin PW composites. The study revealed that the composite material consisting of PW (7:3 wt%) modified with 20 wt% NaOH showed high values in terms of tensile strength (94.2 MPa) and elastic modulus (E-modulus) (7.1 GPa). Composites prepared with modified PWs exhibited hydrophobic surfaces.