Biodegradable composites made from maize flour filled with olive husk fibers

Abstract

The development of biomaterials based on maize flour reinforced with natural fiber was studied with the aim of replacing conventional polymers of petrochemical origin and to simplify assimilated rubbish managing strategies, which reduces the pollution of the environment. In this study, several composites based on plasticized maize flour (PMF) reinforced by the olive husk flour (OHF) in a range from 10% to 40% (wt.%) have been produced with double screw extruder. 15% (wt.%) of low-density polyethylene (LDPE) and graft polyethylene combined with maleic anhydride (PE-g-MA) bonding substance at 5 (wt.%) were added to obtain high mechanical characteristics and improve blend compatibility. Scanning electron microscope (SEM) analysis showed that the fibers were well dispersed in matrix. The Fourier-transform infrared (FTIR) spectroscopy analysis revealed an increase in the absorption bands characteristic of hydroxyl groups and the anhydroglucose ring O-C stretch by raising OHF amount in composites. Thermal stabilization and density of composites increase with the percentage of fiber. For fiber weights of 10 and 40 (wt.%), the tensile strength increased as of 8.4 to 16.4 MPa and the Young modulus as of 70 to 245%, respectively. The biodegradability of samples was tested by burying them in the soil for 90 days. The weight loss test showed that the biodegradability accelerated with the increase in OHF quantity in the PMF. The latter finding was confirmed by FTIR analysis and deteriorated surface of samples examined by SEM analysis.