This study extends a work started on the new bio-composite materials; polymer/eggshell composites. Polypropylene/chicken eggshell composites were chosen and prepared via melt extrusion. The mechanical and thermal behavior of composites containing 10–40 wt% of untreated and strearic acid-treated eggshell were studied. The results show improvements in tensile modulus of composites while the values of tensile strength, strain at break, and impact strength decrease compared to that of neat polypropylene. The crystallization temperature, Tc, is clearly increased by incorporating 10 wt.% eggshell into polypropylene while a margin effect on the degree of crystallinity is seen. It can be concluded that composites need to be further studied and modified for possible use of eggshell as filler without scarifying the mechanical properties of the neat polymer matrix.
ABSTRACT:The structure-property relationship of sugarcane bagasse fiber-filled polyamide 6 blends at different blend compositions has been investigated. Blends were prepared in the composition of wt % PA6/wt % bagasse as follows: 98/2, 95/5, and 90/10 for three fiber length ranges (Ͻ100, Ͻ250, and Ͻ500 m) using a twin-screw extruder. Thermal properties were evaluated by measuring the glass transition temperature T g , enthalpy of fusion ⌬H f , crystallinity X c and thermogravimetry, TG. Results showed that T g of the composites changed with change in fiber loading and length. The X c as well as ⌬H f of the blends reduced to almost half its value for the neat PA6. The thermogravimetric curves TG showed that the thermal stability of the composites was lower than that of the neat PA6. Rheological properties were studied as a function of fiber loading, fiber length, shear rate, and temperature. The viscosity of composites increased with increasing fiber loading and length at low shear rates but decreased below that of neat PA6 at high shear rates. It was also found to be temperature sensitive, and influenced by fiber lengths particularly at higher temperatures. The morphology of the blends was studied using a Leica laser scanning confocal microscopy at two different regions: at the wall, and the core. The micrographs of the blends showed that fibers present in the form of bundles were found at the wall of the extrudates and increased in volume with increase in both length and concentration, at the same temperature and shear stress. In the core region, there is laminar flow, presenting striation morphology, with the omnipresent bundles of fibers dispersed in the matrix. At higher shear rates, the bundles were pushed to the wall.
The surface properties of the OSW and NLS are measured with the dynamic contact-angle technique. The x-ray photoelectron spectroscopy (XPS) of the OSW reveals that the OSW possesses various reactive functional groups namely hydroxyl groups (OH). Hybrid filler from NLS and OSW were incorporated into carboxylated nitrile rubber (XNBR) to produce XNBR hybrid composites. The reaction of OH groups from the OSW with COOH of the XNBR is checked by attenuated total reflectance spectra (ATR-IR) of the composites. The degree of curing DM (maximum torque-minimum torque) as a function of hybrid filler as derived from moving die rheometer (MDR) is reported. The stress-strain behavior of the hybrid composites as well as the dynamic mechanical thermal analysis (DMTA) is studied. Bonding quality and dispersion of the hybrid filler with and in XNBR are examined using scanning-transmission electron microscopy (STEM in SEM).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.