Waxes

Wax has traditionally referred to a substance that is secreted by bees (beeswax) and used by them in constructing their honeycombs.

In modern terms, wax is an imprecisely defined term generally understood to be a substance with properties similar to beeswax, namely
* plastic (malleable) at normal ambient temperatures
* a melting point above approximately 45 C (which differentiates waxes from fats and oils)
* a relatively low viscosity when melted (unlike many plastics)
* insoluble in water
* hydrophobic

Waxes may be natural or artificial. In addition to beeswax, carnauba (a vegetable wax) and paraffin (a mineral wax) are commonly encountered waxes which occur naturally. Ear wax is an oily substance found in the human ear. Some artificial materials that exhibit similar properties are also described as wax or waxy.

Chemically, a wax may be an ester of ethylene glycol (ethan-1,2-diol) and two fatty acids, as opposed to a fat which is an ester of glycerin (propan-1,2,3-triol) and three fatty acids. It may also be an ester of a fatty acid with a fatty alcohol. It is a type of lipid.

Wax types

Animal and insect waxes:

* Beeswax - produced by honeybees
* Chinese wax - produced by scale insects Coccus ceriferus
* Shellac wax - from the lac insect Coccus lacca
* Spermaceti - from the head cavities and blubber of the Sperm Whale
* Lanolin (wool wax) - from the sebaceous glands of sheep

Vegetable waxes:

* Bayberry wax - from the surface of the berries of the bayberry shrub
* Candelilla wax - from the Mexican shrubs Euphorbia cerifera and E. antisyphilitica
* Carnauba wax - from the leaves of the Carnauba Palm
* Castor wax - catalytically hydrogenated castor oil
* Esparto wax - a byproduct of making paper from esparto grass
* Japan wax - a vegetable tallow (not a true wax), from the berries of Rhus and Toxicodendron species
* Jojoba oil - pressed from the seeds of the jojoba tree, a replacement for spermaceti
* Ouricury wax - from the Brazilian Feather Palm
* Rice bran wax - obtained from rice bran

Mineral waxes

* Ceresin waxes
* Montan wax - extracted from lignite and brown coal
* Ozocerite - found in lignite beds
* Peat waxes

Petroleum waxes

* Paraffin wax - made of long-chain alkane hydrocarbons
* Microcrystalline wax - with very fine crystalline structure

Synthetic waxes

* Polyethylene waxes - based on polyethylene
* Fischer-Tropsch waxes
* Chemically modified waxes - usually esterified or saponified
* substituted amide waxes
* polymerized α-olefins

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