CELLULOSE

LIGNIN

Cellulose

Glucose-based Polymeric Fibres

The cellulose is an organic compound of polymeric nature. The reaction of the condensation of D-Glucose monomers gives rise to the synthesis of a linear macromolecule (polymer). The glucose molecules are united by a glyosidic bond called beta (1-4) that connects the site 1 of a unity with the site 4 of the following unit with the OH equatorial anomeric.

The partial cell hydrolysis  creates a cellobiose, made of two glucose units always with beta bond (1-4). Unlike the cellulose, the starch has alfa glyosidic bonds. The mammals have enzymes (amylases) that can hydrolyse only the alfa bond. Therefore they can metabolize the starch but not the cellulose.

The cellulose does not have a homogeneous chemical-physical structure, in fact we can distinguish phases with a different crystallization grade. The presence of many OH-groups entails the formation of many hydrogen bonds among different sites of the polymeric chain and therefore supports the crystallization and the water absorption.

The hemicellulose is different from the cellulose because it is composed not only of glucose but also of other monosaccharides (pentosans and hexosans) and their low polymerization grade.

 

     

 

 

 

 

 

 

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