Young's Modulus of Plant Fibers

A simple model is used to explain the decrease of the Young's modulus of plant fibers as the apparent diameter is increased. The assumption made in this work is that the fiber consists of a very thin but stiff outer shell, and a thicker but less stiff inner shell which defines the load bearing area. The model is favorably compared with the experimental data reported in the literature for flax, hemp and stinging nettle fibers.