EFFECT OF BACTERIAL AND CHEMICAL RETTING ON KENAF FIBER QUALITY

Decorticated kenaf stalks were retted by bacterial and chemical processes. Bacterial retting was done in troughs at a temperature of 30 +/- 2-degrees-C. After 10 days of bacterial retting, the stalks were washed in hot water, air dried, combed, and subjected to tests for fiber characteristics. Chemical retting was done by boiling stalks in 7% sodium hydroxide for 1 hour, after which they were washed, neutralized in 0.2% acetic acid, washed, air dried, and combed. Fiber characteristics such as bundle strength, elongation at break, color, luster, reed length, and gum content were compared for fibers extracted by both processes. Bundle strength, gum content, and reed length were lower for chemically retted fibers as compared with bacterially retted fibers. Gum content of bacterially retted fibers was uniform, and they were superior in luster. Residual gum content of bacterially retted fibers was 21-23% versus 7-12% for chemically retted fibers. Fiber quality from bacterial retting was superior, but a method that combines bacterial and chemical processing may have some merit. The feasibility of large-scale chemical retting and incorporation of fibers into nonwoven and woven textiles is being investigated.