Factors influencing the tensile properties of ramie

Abstract

Many investigators have claimed that tensile breakage of native cellulose fibers occurs primarily by repture of covalent bonds in the cellulose molecules rather than by chain slippage resulting from repture of such interchain bonds as hydrogen bonds. This claim has been made partly on the basis of a comparison of tensile properties of ramie fiber and of the fully esterified counterpart. This comparison indicated that the breaking load of ramie was similar to that of the fully esterified fiber. In studying the tensile properties of ramie fiber and of fully acetylated ramie fiber, we found that the degree of polymerization of the fiber was lowered during the acetylation process. Also, it was evident that both degree of polymerization and degree of crystallinity are important factors to be considered when comparing the tensile strength of native cellulose fibers and their acetylated counterparts. Although the primary cause of tensile breakage of native cellulose fibers may be due to chain scission rather than to chain slippage, it is difficult to claim supporting evidence for this theory from studies made so for on the tensile properties of esterified ramie fibers.