Improved Chemical Retting of Kenaf Fibers

Abstract

Moldable nonwoven fabrics for automotive applications make up a large market, but they are currently made from synthetic fibers that are not easily biodegraded. Incorpo rating kenaf fibers into automotive nonwovens may enhance their biodegradability, while imparting improved acoustical insulation and reducing vehicle weight (kenaf fiber density is 1.4 versus 2.55 for glass). Traditional biological (water) retting of kenaf is tedious, time consuming, costly, and environmentally sensitive. As a consequence, it does not provide necessary incentives for a new, potentially large kenaf market. Continuing research efforts at the Southern Regional Research Center (SRRC) nave resulted in simplified chemical retting procedures for two mechanically harvested, distinctly different varieties of kenaf, the forage harvested Tainung-2 (T-2, 3.75-7.5 cm short fibers) and the naturally retted cultivar Everglades-41 (E-41, 100-125 cm long ribbons). In this paper, an improved caustic formulation for effective retting and a special soap finish for improved carding of kenaf fibers are suggested. Development of some nonwoven fabrics containing SRRC refined kenaf fibers for automative applications are discussed in a subsequent paper. Successful use of kenaf in automotive nonwovens is expected to lead to a considerable expansion in kenaf cultivation.