Cellulose
Cellulose is an organic compound with the formula (C
6H
10O
5)
n, a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. 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. Cellulose is the most abundant organic polymer on Earth. The cellulose content of cotton fiber is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%.
| Identifiers | |
|---|---|
| ChEMBL | |
| ChemSpider |
|
| ECHA InfoCard | 100.029.692 |
| EC Number |
|
| E number | E460 (thickeners, ...) |
| KEGG | |
PubChem CID |
|
| UNII | |
CompTox Dashboard (EPA) |
|
| Properties | |
| (C 12H 20O 10) 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 |
| none | |
| Thermochemistry | |
Std enthalpy of formation (ΔfH⦵298) |
−963,000 kJ/mol |
Std enthalpy of combustion (ΔcH⦵298) |
−2828,000 kJ/mol |
| Hazards | |
| NFPA 704 (fire diamond) | |
| NIOSH (US health exposure limits): | |
PEL (Permissible) |
TWA 15 mg/m3 (total) TWA 5 mg/m3 (resp) |
REL (Recommended) |
TWA 10 mg/m3 (total) TWA 5 mg/m3 (resp) |
IDLH (Immediate danger) |
N.D. |
| 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).
Infobox references | |
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.
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.