Matéria (Rio de Janeiro)
On-line version ISSN 1517-7076
RAMIREZ, María Guadalupe Lomelí et al. Preparation and characterization of biodegradable composites based on Brazilian cassava starch, corn starch and green coconut fibers. Matéria (Rio J.) [online]. 2010, vol.15, n.2, pp. 330-337. ISSN 1517-7076. http://dx.doi.org/10.1590/S1517-70762010000200034.
Increasing search for new materials with high premium on eco-friendliness, new trend is emerging in materials development such as composites, which are well established for a wide variety of applications. With growing interest and importance of renewable bioresources has led to more stress on the use of locally available materials. This paper presents preliminary results on the preparation and characterization of composites based on Brazilian coconut fibers and starches of cassava and corn. The raw materials were characterized for their morphology, chemical composition, and thermal properties and X-ray diffraction studies. Coir fibers were also tested for their tensile properties showing increasing strength and Young's modulus with decreasing diameter, while the % elongation remaining constant. Lignin content of coir was found to be 35%. Structure and properties of composites containing 0, 5 10, 15% fibers in both the matrices and prepared by compression molding would be compared. For the 2 types of starch, there was an increase in the tensile strength by the increasing proportion of fiber. The effect of moisture in the composite stress affects the strength and percentage elongation. The water absorption was higher in the composites made from cassava starch.
Keywords : Cassava starch; corn starch; coconut fiber; glycerol.