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Many properties of cellulose depend on its chain length or degree of polymerization, the number of glucose units that make up one polymer molecule. Cellulose from wood pulp has typical chain lengths between 300 and 1700 units; cotton and other plant fibers as well as bacterial cellulose have chain lengths ranging from 800 to 10,000 units. [6]
Cellulose is a polymer made of repeating glucose molecules attached end to end. [4] A cellulose molecule may be from several hundred to over 10,000 glucose units long. Cellulose is similar in form to complex carbohydrates like starch and glycogen. These polysaccharides are also made from multiple subunits of glucose.
The major polymers that make up wood (largely secondary cell walls) include: cellulose, 35-50%; xylan, 20-35%, a type of hemicellulose; lignin, 10-25%, a complex phenolic polymer that penetrates the spaces in the cell wall between cellulose, hemicellulose and pectin components, driving out water and strengthening the wall.
In contrast, each polymer of cellulose comprises 7,000–15,000 glucose molecules. [5] In addition, hemicelluloses may be branched polymers, while cellulose is unbranched. Hemicelluloses are embedded in the cell walls of plants, sometimes in chains that form a 'ground' – they bind with pectin to cellulose to form a network of cross-linked fibres.
For example, cellulose is an unbranched homopolysaccharide made up of glucose monomers connected via beta-glycosidic linkages; glycogen is a branched form, where the glucose monomers are joined by alpha-glycosidic linkages. Depending upon the molecules attached that are of the following types:
The secondary cell wall consists primarily of cellulose, along with other polysaccharides, lignin, and glycoprotein. It sometimes consists of three distinct layers - S 1, S 2 and S 3 - where the direction of the cellulose microfibrils differs between the layers. [1] The direction of the microfibrils is called microfibril angle (MFA). In the ...
Pulp made from non-wood plant sources or recycled textiles is manufactured today largely as a speciality product for fine-printing and art purposes. [8] Modern machine- and hand-made art papers made with cotton, linen, hemp, abaca, kozo, and other fibers are often valued for their longer, stronger fibers and their lower lignin content.
[2] and the cellulose is a polymer of six-carbon sugar C 6 H 12 O 6 . [3] Cellulose fibers are considered to be a plant’s structural building blocks and are tightly bound to lignin, but the biomass can be deconstructed using Acid hydrolysis, enzymatic hydrolysis, organosolv dissolution, autohydrolysis or supercritical hydrolysis. A more ...