Effect of Alkali Treatment on the Tensile Properties of Grape Cane Fibers by Integrating Digital Image Correlation Method

The objective of this study was to investigate tensile properties of two grape cane fibers, namely, outer bark (OB) and inner bark (IB). The cane is a necessary annual by-product from vineyards and is produced at approximately 36 million tons yearly around the world, which currently has no substantial commercial utilization. Grape cane fibers were subjected to an alkali treatment, at different concentrations, to separate the fibers from the cane. Moreover, two displacement methods such as system compliance ( C s ) and digital image correlation (DIC) were performed to determine Young’s modulus of the samples, and the results were compared. The OB fibers had better overall properties than IB fibers. The effect of the treatment concentrations (1, 3, 5, and 7 wt% of sodium hydroxide) and gage lengths (10, 25, and 40 mm) on the tensile properties was not consistent for both fiber types. The DIC method consistently yielded greater tensile modulus of the samples than the  C s  method for OB fibers.