Cellulose

Cellulose[1]
Cellulose, a linear polymer of D-glucose units (two are shown) linked by β(1→4)-glycosidic bonds
Three-dimensional structure of cellulose
Identifiers
ChEMBL
ChemSpider
  • None
ECHA InfoCard 100.029.692 Edit this at Wikidata
EC Number
  • 232-674-9
E number E460 (thickeners, ...)
KEGG
UNII
Properties
(C
6
H
10
O
5
)
n
Molar mass 162.1406 g/mol per glucose unit
Appearance white powder
Density 1.5 g/cm3
Melting point 260–270 °C; 500–518 °F; 533–543 K (decomposes)[2]
none
Thermochemistry
−963 kJ/mol[clarification needed]
−2828 kJ/mol[clarification needed]
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1
1
0
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 15 mg/m3 (total) TWA 5 mg/m3 (resp)[2]
REL (Recommended)
TWA 10 mg/m3 (total) TWA 5 mg/m3 (resp)[2]
IDLH (Immediate danger)
N.D.[2]
Related compounds
Related compounds
Starch
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Cellulose is an organic compound with the formula (C
6
H
10
O
5
)
n
, a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units.[3][4] Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms.[5] Cellulose is the most abundant organic polymer on Earth.[6] The cellulose content of cotton fibre is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%.[7][8][9]

Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton.[6] Cellulose is also greatly affected by direct interaction with several organic liquids.[10]

Some animals, particularly ruminants and termites, can digest cellulose with the help of symbiotic micro-organisms that live in their guts, such as Trichonympha. In human nutrition, cellulose is a non-digestible constituent of insoluble dietary fiber, acting as a hydrophilic bulking agent for feces and potentially aiding in defecation.

  1. ^ Nishiyama Y, Langan P, Chanzy H (2002). "Crystal Structure and Hydrogen-Bonding System in Cellulose Iβ from Synchrotron X-ray and Neutron Fiber Diffraction". J. Am. Chem. Soc. 124 (31): 9074–9082. doi:10.1021/ja0257319. PMID 12149011.
  2. ^ a b c d NIOSH Pocket Guide to Chemical Hazards. "#0110". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ Crawford, R. L. (1981). Lignin biodegradation and transformation. New York: John Wiley and Sons. ISBN 978-0-471-05743-7.
  4. ^ Updegraff D. M. (1969). "Semimicro determination of cellulose in biological materials". Analytical Biochemistry. 32 (3): 420–424. doi:10.1016/S0003-2697(69)80009-6. PMID 5361396.
  5. ^ Romeo T (2008). Bacterial biofilms. Berlin: Springer. pp. 258–263. ISBN 978-3-540-75418-3.
  6. ^ a b Klemm D, Heublein, Brigitte, Fink, Hans-Peter, Bohn, Andreas (2005). "Cellulose: Fascinating Biopolymer and Sustainable Raw Material". Angew. Chem. Int. Ed. 44 (22): 3358–3393. doi:10.1002/anie.200460587. PMID 15861454.
  7. ^ Cellulose. (2008). In Encyclopædia Britannica. Retrieved January 11, 2008, from Encyclopædia Britannica Online.
  8. ^ Chemical Composition of Wood. Archived October 13, 2018, at the Wayback Machine. ipst.gatech.edu.
  9. ^ Piotrowski, Stephan and Carus, Michael (May 2011) Multi-criteria evaluation of lignocellulosic niche crops for use in biorefinery processes Archived April 3, 2021, at the Wayback Machine. nova-Institut GmbH, Hürth, Germany.
  10. ^ Mantanis GI, Young RA, Rowell RM (1995). "Swelling of compressed cellulose fiber webs in organic liquids". Cellulose. 2 (1): 1–22. doi:10.1007/BF00812768. ISSN 0969-0239.

Cellulose

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