Effects of Alkalization on Physical and Mechanical Properties of Biologically Degummed Okra Bast and Corn Husk Fibers

In this study, biologically degummed okra bast and corn husk fibers were subjected to alkalization processes. Alkalization treatments resulted in decrease of linear density of the biologically degummed fibers. Increment in alkali concentration resulted in an initial increase then a successive decrease in all tensile indicators: initial modulus, breaking tenacity and breaking elongation. 3 g/L NaOH-treated fibers showed the best tensile characteristics for both okra bast and corn husk fibers. The IR spectra analysis suggested elimination of extracellulosic materials upon alkaline treatment. The ranges for properties of the produced okra bast and corn husk fibers can be summarized in consecutive order as linear density of 9.7–12.3 and 20.0–24.3 tex; initial modulus between 1257-1897 and 156.4–354.6 cN/tex; breaking tenacity range in 28.0–46.8 and 6.37–15.2 cN/tex; and elongation in the range 2.0–2.5% and 8.7–19.9%. The properties of obtained okra bast fibers are found to be superior to corn husk fibers and comparable to that of conventional bast fibers.