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Effect of maleic anhydride treatment on the mechanical properties of sansevieria fiber/vinyl ester composites AIP Conference Proceedings 1823, 020097 (2017) Rochim@material.itb.ac.idAbstract. In this study, Sansevieria trifasciata fibers were treated by NaOH with concentration 1%,3%, and 5wt% at 100 0 C for 2 hours. Chesson-Datta methods was used to determine the lignocellulose content of raw sansevieria fibers and to investigate effect of alkali treatment on lignin content of the fiber. Mechanical properties and thermal properties of treated and untreated fibers were measured by means of tensile testing machine and thermogravimetric analysis (TGA).The cellulose and lignin contents of raw sansevieria fiber obtained from Chesson-Datta method were 56% and 6% respectively. Mechanical testing of fibers showed the increase of tensile strength from 647 MPa for raw fibers to 902 MPa for 5wt% NaOH treated fibers. TGA result showed the alkali treatment increase the thermal resistance of fibers from 288°C for raw fibers to 307°C for 5% NaOH treated fiber. It was found that alkali treatment affect the mechanical properties and thermal properties of sansevieria fibers.

The increasing demand for vehicles is resulting in environmental problems, such as a higher demand for fossil fuels and higher CO2 emissions. Lightweight materials, such as fiberreinforced polymers, have been used in automotive components to reduce the weight, fuel consumption, and CO2 emissions of vehicles. Natural fibers are often used as substitutes for glass fibers because they are abundant and require less energy to produce compared to glass fibers. The present research focused on the preparation and characterization of composites reinforced with Sansevieria trifasciata fiber (STF). High-impact polypropylene (HIPP) and vinyl ester (VE) were chosen and compared as matrix materials. The results showed that the mechanical properties of the produced biocomposites increased with increasing amounts of fiber, alkaline treatment, and unidirectional fiber orientation. A tensile strength of 59.77 MPa and a stiffness of 1.97 GPa were obtained for STF/HIPP composites with unidirectional alkali treatment and a 15% volume fraction of fiber. Moreover, a tensile strength of 121.1 MPa and a stiffness of 7.65 GPa were obtained for STF/VE composites with unidirectional alkali treatment and a 15% volume fraction of fiber. The STF/VE biocomposites were comparable to commercial glass fiber composites for automotive applications and even exhibited greater tensile strength properties.

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Abstract. The formation of organometal-halide perovskite crystal is simply based on stoichiometry reaction. However, the formation process seems to be sensitively affected by some process parameters such as concentration and temperature of precursor solution. In this work, we studied the formation of CH 3 NH 3 PbI 3 (MAPbI 3 ) crystal in mesoporous TiO 2 layer deposited by spin coating technique. Perovskite layers were characterized by X-Ray Diffraction (XRD) and its surface morphology were investigated by Scanning Electron Microscope (SEM). Perovskite layers obtained from precursor solution at 40°C and 60°C show a mesh-like structure. Meanwhile, for higher precursor solution temperature (80°C), it shows a flake-like structure. However, precursor solution at 60°C produced the best conversion of precursor solution with the smallest percentage of the remaining unconverted PbI 2 inside the produced crystal layer. These experimental results also showed that the best crystallization degree is obtained from 1.0 M precursor solution. The photovoltaic characteristics of their solar cells seem to have a correlation with the quantity of unconverted PbI 2 . High PbI 2 content significantly decreased the Filling Factor of the solar cell.

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