PERUBAHAN SIFAT MEKANIS DAN FISIS KOMPOSIT HIBRIDA KENAF/E-GLASS/POLIVINIL KLORIDA (PVC) AKIBAT VARIASI PERBANDINGAN FRAKSI VOLUME SERAT KENAF DAN E-GLASS
Abstract
Car interiors are examples of E-glass/polyvinyl chloride (PVC) composites material application . Nevertheless, the E-glass/PVC composites waste are non-biodegradable materials which may caused negative impact on human and environment. Therefore, this study is aimed to produce a hybrid composite material by combining the E-glass fiber and kenaf fiber as reinforcement. Kenaf fiber was selected because of its superior characteristics, which are renewable, lightweight, cheap, eco-friendly, non-toxic, non-abrasive, high mechanical properties, and its abundant availability, especially in Indonesia.
The composite materials of kenaf/E-glass/PVC composite was fabricated by means of hot compression molding at 160°C and at 130 kg/cm2 for 10 minutes. The alkalization of kenaf fiber with NaOH solution were performed before the fabrication process. The E-glass fiber was heat-treated at 400°C for 20 minutes. In this study, the matrix to filler ratio of 80/20 was used. The variations of kenaf fiber/E-glass ratios were 20/0, 15/5, 10/10, 0/20 wt %. The mechanical testing was bending test, and physical test was water absorption test. The bending test was done according to the ASTM D790 standard, while the water absorption test and thickness swelling were done according to the ASTM D570 standard. The mechanical property changes were characterized from the fracture structures using a scanning electron microscope (SEM) and optical microscopy.
The kenaf/E-glass/PVC composite at 80/5/15 ratio showed the highest bending strength and modulus of elasticity, 100.1 MPa and 2.67 GPa. The kenaf/E-glass/PVC composite at 80/10/10 ratio showed the highest bending strain at 5.43 %. The kenaf/E-glass/PVC composite at 80/5/15 ratio showed the lowest water absorption and thickness swelling with the weight and thickness changes of 4.84 % and 2.64 %, respectively. The macrograph and SEM photos showed a strong bond between the matrix and filler, but there were still the voids.