100 Green Composites from Natural Resources
5.3.2 Bast (steM)
Basts (stems) are obtained from the stems of various dicotyledonous plants and are
also referred to as “soft” bers to distinguish them from leafs. Flax, hemp, jute, and
kenaf come under the bast ber category. Bast bundles are composed of elongated
thick-walled ultimate cells joined together both end to end and side by side and
arranged in bundles along the length of the stem. Bast bundles are removed from
parent material by the decorticating process, which consists of removing them from
the stem, the “cortex” comprising the bast and outer barks (Robson et al. 1993).
5.3.3 seeds
The seeds are generally formed from a single biological cell. It is reported that more
than one cell t ...