CHAPTER 4 



PROPERTIES AND USES OF CELL WALLS 

 AND THEIR DERIVATIVES 



I. Woods, Fibers, and Plastics 



Cellulose, uronic acid fibers and plastic cell wall materials have 

 been used by Man in many forms from early times. Twines of 

 flax and hemp were known to Stone Age Man, and linen fabrics 

 were prepared by the Swiss lake dwellers of the Neolithic. The 

 arts of spinning cotton and flax date back to Egyptian and Indian 

 civilizations of the third millennium B.C., and refined cotton fabrics 

 were introduced into European civilizations in the fourth century 

 B.C. Other fibers unknown to the Mediterranean peoples, hemp, 

 jute and ramie, for example, were known to the Chinese and Indian 

 peoples from ancient times. 



The useful natural cellulosic fibers are of diverse origin and 

 include seed hairs, bast fibers, and leaf fibers. 



The seed hair products are principally cotton and kapok. 

 Cotton, from Gossypium (Malvaceae) contain 85-90 per cent 

 cellulose, 6-8 per cent water. Its fibers are 15-35 mm in length 

 and 20-1 0[x in diameter. They are flattened and twisted single cells. 

 Kapok, from the Javanese plant Ceiba pentandra (Bombacaceae) 

 contains 65 per cent cellulose, 12 per cent water and 15 per cent 

 lignin. The flossy material is valued for insulating and buoyancy 

 properties. 



Flax (Linum usitatissimum, Linaceae), hemp {Cannabis sativa, 

 Moraceae), jute {Corchorus capsularis and C. olitorius, Tiliaceae) 

 and ramie (Boehmeria nivea), are the principal sources of bast 

 fibers. The fibers contain 65-90 per cent a-cellulose, 8-12 per cent 

 water and various amounts of other materials. Ramie is notable 

 for the purity of its cellulose; jute for a high lignin content. Flax 



