Structure of Naturally Coloured Cottons

Previous work on the morphology of naturally coloured green cottons has suggested that the secondary wall of the fibres consists of alternate layers of cellulose and a waxy organic substance called suberin. The work described in this paper has shown that modem varieties of green cotton do contain a large proportion of suberin. Data from fibre swelling is consistent with alternate layers of suberin and cellulose in the secondary wall. The naturally coloured fibres have a lower tenacity and work of rupture than conventional white fibres although they have an acceptable level of textile properties. The crystallinity of the coloured fibres is lower than of white cotton, but the cellulose has the Cellulose I structure normally found in cotton.