No abstract

Ramie (Boehmeria nivea) is one of the strongest natural cellulose fibers. Optimizing abundant resources ramie as a candidate materials used for reinforcing in polymeric composite material is a must to obtained high-performance natural fibers reinforced polymer especially for bulletproof panel or high-impact flexibility safer structures. Ramie woven was treated using common chemical solvents that were ethanol, methyl ethyl ketone, acetone, and silane as coupling agent. Composite panels were made by hand lay-up process with epoxy as a matrix. These prototype bulletproof panels were to be believed lighter in weight and much lower economic cost than conventional bulletproof panels made from ceramic plate, Kevlar/aramid composite, and steel-based material as a popular today in military standard antiballistic equipments. From the bullet testing result, it showed that panel could be able to resist the penetration of high-impact projectile for level II with some fractures phenomenon. Level IV ballistic testing showed that all prototype panel could not resist the high-impact velocity of the projectile yet. It was found that ramie Downloaded from fibers have sufficient breaking strength and toughness for level II bullet testing, although still needs improvements to optimize process parameters to meet a very high military standard and application KEY WORDS: Ramie woven composite, bulletproof panel, ballistic testing, NIJ standard.

The research aim is to investigate the effect of alkali treatment on the crystalline structure of Mendong fiber. The experiment was conducted by immerse fibers in 100 ml NaOH solution by a concentration of 2.5%, 5%, 7.5%, and 10% for 2 hours at the room temperature. The specimens were characterized by X-ray diffraction method. The morphology of fiber treated by alkali was observed by Scanning Electron Microscope. The result shows that the crystalline structure of cellulose in Mendong fiber was changed in alkali treatment. It was found that both the degree of crystallinity and crystalline index of Mendong fiber was increased until alkali treatment concentration of 7.5%.

The effects of alcohol, acetone, and methyl ethyl ketone solvent-based treatment on surface topography of ramie single fiber are investigated. In this study, the average of specific porous volume and specific surface area of ramie single fiber are determined to interpret the effects of the treatment quantitatively using Brunauer-Emmet-Teller surface area method. Fourier Transform Infrared Spectroscopy is applied directly to the fiber to detect the differences of molecular group function in the fiber surface. Qualitatively, scanning electron microscopy was also provided. The result shows that the solvent treatment could improve surface topography to gain matrix penetration when utilizing the fiber into polymeric composite material.