Fabrication process optimization of gombong (Gigantochloa pseudoarundinacea), haur hejo (bambusa tuldoides) and tali (gigantochloa apus) bamboo fibers for structural application

Natural fibers contained in bamboo are beneficial to renewable, biodegradable, abundant availability, and cheap which could be a potential substitute of synthetic materials. Tensile strength of this material is important requirements in various structural application. In this research, fiber fabrication process optimization of three types of local bamboo namely Gombong (Gigantochloa pseudoarundinacea), Haur Hejo (Bambusa tuldoides), and Tali (Gigantochloa apus) was investigated. These fibers were processed by creating a variety of the NaOH concentrations of 4 % and 6 %, immersion times of 1, 2, and 3 hours, and immersion temperatures of 25^oC and 60^oC. The process parameters and its level variations of bamboo fiber fabrication were optimized using Taguchi method. Then the contribution of each process parameter was observed using the analysis of variance (ANOVA). From Taguchi method, the optimal parameter for highest tensile strength was obtained from Tali bamboo, indicated by 4 % NaOH, 2 hours immersion time, and 60^oC immersion temperature. Meanwhile, the ANOVA revealed that the contributions for each parameter are 70 % for bamboo type, 7 % for NaOH concentration, 4 % for immersion time, and 17 % for immersion temperature with error contribution of 2 %. By using these data, it could be concluded that bamboo type selection is a critical parameter to obtain bamboo with high tensile strength. While NaOH concentration, immersion time, and immersion temperature are not critical parameters which gave flexibility in the selection process. FTIR analysis was carried in order to observe chemical bonding in bamboos. The results of FTIR on the bamboo fibers were indicated Tali bamboo has larger lignin levels decreasing than Haur Hejo and Gombong, this indicates in higher tensile strength for Tali bamboo fiber.