FABRICATION OF SANSEVIERIA TRIFASCIATA FIBER REINFORCED NATURAL RUBBER COMPOSITE AS SOFT BODY ARMOR

• Main Author: Aditya Putra, Daniel
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/53966
• Institution: Institut Teknologi Bandung

Body armor is an important equipment in defence sector which provide protection against firearm projectile. Body armor is commonly manufactured from several layers of fiber reinforced composites using high performance fiber such as Kevlar and Dyneema. However, the limited availability, high cost, and lack of local manufacturer of high-performance fibers pose a challenge in the production of body armor in Indonesia. Sansevieria trifasciata is one of the natural fiber sources widely available in Indonesia. Sansevieria fiber has a tensile strength of 345-647 MPa and modulus up to 20.7 MPa, making it a potential source to be used as reinforcement for body armor. Besides fiber, another material which has the capability to transfer the impact energy of bullet and is available in Indonesia, such as natural rubber, is needed as a matrix. In this research, sansevieria fibers in the form of woven cloth was utilized as reinforcement of natural rubber-based composites for soft body armor application. Alkali treatment using NaOH solution with the concentration of 1, 5, 10, 15, and 17.5% was conducted to improve the fiber mechanical properties and the fiber-rubber interface. Tensile testing, density measurement, FTIR, and Chesson-Datta testing were performed to evaluate the effect of alkali treatment process. Ribbed smoked sheet (RSS) rubber was utilized as matrix in this research. Compounding process was performed using carbon black as filler with the loading variation of 10, 20, and 30 phr, and CBS as accelerator with the loading variation of 0,4; 2; and 5 phr. Rheometer testing, tear testing, tensile, as well as rebound testing were conducted to evaluate the mechanical properties of the rubber matrix. Preparation of sansevieria/rubber composite was conducted using impregnation method by immersing sansevieria cloth in rubber-toluene solution. Vulcanization process was conducted in 150 °C for 15 minutes using compression molding machine. Tensile testing and volume fraction measurement were conducted to evaluate the quality of the resulting composite. Ballistic testing to evaluate the performance of composite as body armor was conducted using LS-DYNA simulation against penetration by NIJ level IIIA bullet. The result showed that alkali treatment with NaOH concentration of 1% resulted in fibers with tensile strength as high as 1400.4 MPa. The highest energy absorption of rubber was obtained by the compound filled with 0.4 phr accelerator and 30 phr carbon black, with the rebound resilience value of 52.2%. The resulting sansevieria/rubber composite consisted of 3 layers of sansivera fabric had a tensile strength up to 101.37 MPa. The optimum composite thickness which had the capability to resist NIJ level IIIA bullet based on the simulation result was 15 mm.