Experimental investigation of alkaline treatment processes (NaOH, KOH and ash) on tensile strength of the bamboo fiber bundle

The aim of this experimental research is to investigate the effect of different alkali solutions, their different concentration, and the soaking time on tensile strength of bamboo fiber bundles. The results of this research will suggest the method to extract bamboo fiber in order to develop biodegradable composite materials in the future. Bamboo strips were mechanically separated from Rough Giant Bamboos, and they were soaked in three different alkali solutions based on NaOH, KOH, and ash with three individual concentrations (5%, 10%, 20% w/w) for eleven different soaking times. The bamboo strips were then washed and naturally air-dried before separating bamboo fibers bundles (cross-section area between 0.06 and 0.27 mm2) by hand pull off. The tensile strengths of bamboo fiber bundles were determined according to ASTM D3039 standard whereas paper grips technique was applied to prevent damage from the machine clamps. The results suggest that the optimal time for soaking bamboo strips is 48 h for all solution and concentration. Moreover, soaking bamboo strips in KOH, and NaOH with more than 5% (10%, 20%) concentration, bamboo fiber bundles were destroyed. On the other hand, soaking bamboo strips in all concentrations of ash solution, and 5% concentration of KOH, and NaOH provides the same tensile strength value as the one with the soaking bamboo strips in distilled water. Additionally, the alkali solutions have proven to be able to protect bamboo fibers from fungus growth in contrast to distilled water.