Editing Wax

{{Short description|Class of organic compounds which are malleable at room temperature}}
{{other uses}}

[[Image:Cetyl-palmitate.svg|thumb|right|[[Cetyl palmitate]], a typical [[wax ester]]]]
[[Image:Beeswax foundation.jpg|thumb|Commercial [[honeycomb]] foundation, made by pressing beeswax between patterned metal rollers]]

'''Waxes''' are a diverse class of [[organic compound]]s that are [[lipophilic]], [[malleability|malleable]] solids near ambient temperatures.  They include [[higher alkanes]] and [[lipid]]s, typically with [[melting point]]s above about 40&nbsp;°C (104&nbsp;°F), melting to give low [[viscosity]] liquids. Waxes are [[Solubility|insoluble]] in water but soluble in nonpolar organic solvents such as [[hexane]], [[benzene]] and [[chloroform]].  Natural waxes of different types are produced by plants and animals and occur in [[petroleum]].

== Chemistry ==
[[File:MODOCeroline.jpg|thumb|Ceroline brand wax for floors and furniture, first half of 20th century. From the [[Museo del Objeto del Objeto]] collection.]]
Waxes are organic compounds that characteristically consist of long [[aliphatic]] [[alkyl]] chains, although aromatic compounds may also be present. Natural waxes may contain unsaturated bonds and include various [[functional group]]s such as [[carboxylic acid|fatty acids]], [[primary alcohol|primary]] and [[secondary alcohol]]s, [[ketones]], [[Aldehyde|aldehydes]] and fatty acid [[ester]]s.  Synthetic waxes often consist of [[homologous series]] of long-chain aliphatic hydrocarbons ([[alkane]]s or paraffins) that lack [[functional group]]s.<ref name=Ull/>

=== Plant and animal waxes ===
Waxes are [[biosynthesis|synthesized]] by both plants and animals.  Those of animal origin typically consist of [[wax ester]]s derived from a variety of fatty acids and carboxylic alcohols.  In waxes of plant origin, characteristic mixtures of unesterified hydrocarbons may predominate over esters.<ref name=Baker/> The composition depends not only on species, but also on geographic location of the organism.

==== Animal waxes ====
The best-known animal wax is [[beeswax]], used in constructing the [[honeycomb]]s of beehives, but other insects also secrete waxes.  A major component of beeswax is myricyl palmitate which is an [[ester]] of [[triacontanol]] and [[palmitic acid]].  Its melting point is {{Convert|62-65|C}}. [[Spermaceti]] occurs in large amounts in the head oil of the [[sperm whale]]. One of its main constituents is [[cetyl palmitate]], another ester of a [[fatty acid]] and a [[fatty alcohol]]. [[Lanolin]] is a wax obtained from wool, consisting of esters of [[sterol]]s.<ref name=Ull>Wilhelm Riemenschneider1 and Hermann M. Bolt (2005). "Esters, Organic". ''Ullmann's Encyclopedia of Industrial Chemistry''. Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a09_565.pub2}}.</ref>

==== Plant waxes ====

Plants secrete waxes into and on the surface of their [[plant cuticle|cuticles]] as a way to control evaporation, wettability and hydration.<ref name=Ullmann/> The [[epicuticular wax]]es of plants are mixtures of substituted long-chain aliphatic hydrocarbons, containing alkanes, alkyl esters, fatty acids, primary and secondary alcohols, [[diol]]s, ketones and aldehydes.<ref name=Baker>EA Baker (1982) Chemistry and morphology of plant epicuticular waxes. In The Plant Cuticle. Ed. DF Cutler, KL Alvin, CE Price. Academic Press. {{ISBN|0-12-199920-3}}</ref> From the commercial perspective, the most important plant wax is [[carnauba wax]], a hard wax obtained from the Brazilian palm ''[[Copernicia prunifera]]''. Containing the ester myricyl cerotate, it has many applications, such as confectionery and other food coatings, car and furniture polish, floss coating, and [[surfboard wax]]. Other more specialized vegetable waxes include [[jojoba oil]], [[candelilla wax]] and [[ouricury wax]].

==== Modified plant and animal waxes ====
Plant and animal based waxes or oils can undergo selective chemical modifications to produce waxes with more desirable properties than are available in the unmodified starting material.<ref>{{Cite journal|last1=Floros|first1=Michael C.|last2=Raghunanan|first2=Latchmi|last3=Narine|first3=Suresh S.|date=2016-11-01|title=A toolbox for the characterization of biobased waxes|journal=European Journal of Lipid Science and Technology|volume=119|issue=6|language=en|pages=n/a|doi=10.1002/ejlt.201600360|issn=1438-9312}}</ref> This approach has relied on green chemistry approaches including olefin metathesis and enzymatic reactions and can be used to produce waxes from inexpensive starting materials like vegetable oils.<ref>{{Cite journal|last1=Schrodi|first1=Yann|last2=Ung|first2=Thay|last3=Vargas|first3=Angel|last4=Mkrtumyan|first4=Garik|last5=Lee|first5=Choon Woo|last6=Champagne|first6=Timothy M.|last7=Pederson|first7=Richard L.|last8=Hong|first8=Soon Hyeok|date=2008-08-01|title=Ruthenium Olefin Metathesis Catalysts for the Ethenolysis of Renewable Feedstocks|journal=CLEAN – Soil, Air, Water|language=en|volume=36|issue=8|pages=669–673|doi=10.1002/clen.200800088|bibcode=2008CSAW...36..669S |issn=1863-0669}}</ref><ref>{{Cite journal|last1=Petersson|first1=Anna E. V.|last2=Gustafsson|first2=Linda M.|last3=Nordblad|first3=Mathias|last4=Börjesson|first4=Pål|last5=Mattiasson|first5=Bo|last6=Adlercreutz|first6=Patrick|date=2005-11-17|title=Wax esters produced by solvent-free energy-efficient enzymatic synthesis and their applicability as wood coatings|url=http://xlink.rsc.org/?DOI=b510815b|journal=Green Chemistry|language=en|volume=7|issue=12|pages=837|doi=10.1039/b510815b|issn=1463-9270|access-date=2016-12-06|archive-date=2019-12-09|archive-url=https://web.archive.org/web/20191209163653/https://pubs.rsc.org/en/content/articlelanding/2005/GC/b510815b|url-status=live|url-access=subscription}}</ref>

=== Petroleum derived waxes ===

{{see also|Paraffin wax}}

Although many natural waxes contain esters, paraffin waxes are hydrocarbons, mixtures of alkanes usually in a [[homologous series]] of chain lengths.  These materials represent a significant fraction of petroleum. They are refined by [[vacuum distillation]]. Paraffin waxes are mixtures of saturated n- and iso- [[Alkane|alkanes]], [[naphthenes]], and [[Alkyl group|alkyl]]- and naphthene-substituted aromatic compounds. A typical alkane paraffin wax chemical composition comprises hydrocarbons with the general formula C<sub>''n''</sub>H<sub>2''n''+2</sub>, such as [[hentriacontane]], C<sub>31</sub>H<sub>64</sub>. The degree of branching has an important influence on the properties. [[Microcrystalline wax]] is a lesser produced petroleum based wax that contains higher percentage of isoparaffinic (branched) hydrocarbons and naphthenic hydrocarbons.

Millions of tons of paraffin waxes are produced annually. They are used in foods (such as chewing gum and cheese wrapping), in candles and cosmetics, as non-stick and waterproofing coatings and in polishes.

==== Montan wax ====

[[Montan wax]] is a fossilized wax extracted from coal and [[lignite]].<ref>{{Cite book|url=https://books.google.com/books?id=urFTAAAAMAAJ&q=Montan+wax+is+a+fossilized+wax+extracted+from+coal+and+lignite|title=Wax chemistry and technology|last=Ivanovsky|first=Leo|date=1952|language=en}}</ref> It is very hard, reflecting the high concentration of saturated [[fatty acid]]s and alcohols. Although dark brown and odorous, they can be purified and bleached to give commercially useful products.

==== Polyethylene and related derivatives ====

{{As of|1995}}, about 200 million kilograms of polyethylene waxes were consumed annually.<ref name=Ullmann/>

Polyethylene waxes are manufactured by one of three methods:

# The direct polymerization of ethylene, potentially including co-monomers;
# The thermal degradation of high molecular weight polyethylene resin;
# The recovery of low molecular weight fractions from high molecular weight resin production.

Each production technique generates products with slightly different properties. Key properties of low molecular weight polyethylene waxes are viscosity, density and melt point.

Polyethylene waxes produced by means of degradation or recovery from polyethylene resin streams contain very low molecular weight materials that must be removed to prevent volatilization and potential fire hazards during use. Polyethylene waxes manufactured by this method are usually stripped of low molecular weight fractions to yield a flash point >500 °F (>260 °C). Many polyethylene resin plants produce a low molecular weight stream often referred to as low polymer wax (LPW). LPW is unrefined and contains volatile oligomers, corrosive catalyst and may contain other foreign material and water. Refining of LPW to produce a polyethylene wax involves removal of oligomers and hazardous catalyst. Proper refining of LPW to produce polyethylene wax is especially important when being used in applications requiring FDA or other regulatory certification.{{Citation needed|date=March 2021}}

== Uses ==

Waxes are mainly consumed industrially as components of complex formulations, often for coatings. The main use of polyethylene and polypropylene waxes is in the formulation of colourants for [[plastic]]s. Waxes confer matting effects (i.e., to confer non-glossy finishes) and wear resistance to paints. Polyethylene waxes are incorporated into inks in the form of dispersions to decrease friction. They are employed as [[release agent]]s, find use as slip agents in furniture, and confer corrosion resistance.<ref name=Ullmann>Uwe Wolfmeier, Mr. Hans Schmidt, Franz-Leo Heinrichs, Georg Michalczyk, Wolfgang Payer, Wolfram Dietsche, Klaus Boehlke, Gerd Hohner, Josef Wildgruber "Waxes" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. {{doi|10.1002/14356007.a28_103}}.</ref>

=== Candles ===
[[File:Montana 10 bg 061905.jpg|thumb|Wax candle]]
Waxes such as [[paraffin wax]] or [[beeswax]], and hard fats such as [[tallow]] are used to make [[candle]]s, used for lighting and decoration. Another fuel type used in candle manufacturing includes [[soy]]. [[Soy wax]] is made by the hydrogenation process using soybean oil.

=== Wood products ===
Waxes are used as finishes and coatings for wood products.<ref>{{cite web |url=http://www.minwax.com/wood-products/specialty-products/minwax-paste-finishing-wax |title=Minwax® Paste Finishing Wax &#124; Specialty Products |publisher=Minwax.com |date=2012-01-31 |access-date=2012-12-15 |archive-date=2012-11-05 |archive-url=https://web.archive.org/web/20121105162357/http://www.minwax.com/wood-products/specialty-products/minwax-paste-finishing-wax |url-status=live }}</ref> Beeswax is frequently used as a lubricant on drawer slides where wood to wood contact occurs.

=== Other uses ===
[[File:49-QWSTION-BANANATEX-FABRIC.jpg|thumb|A wax coating makes this [[Manila hemp]] waterproof.]]
[[File:Lavalampe.jpg|thumb|upright=.5|A [[lava lamp]] is a novelty item that contains wax melted from below by a bulb. The wax rises and falls in decorative, molten blobs.]]
[[Sealing wax]] was used to close important documents in the [[Middle Ages]]. [[Wax tablet]]s were used as writing surfaces. There were different types of wax in the Middle Ages, namely four kinds of wax ([[Dubrovnik|Ragusan]], [[Montenegro]], [[Byzantine]], and [[Bulgaria]]n), "ordinary" waxes from [[Spain]], [[Poland]], and [[Riga]], unrefined waxes and colored waxes (red, white, and green).<ref>The rational arts of living: Ruth and Clarence Kennedy Conference in the Renaissance, 1982, page 187, Studies in History, No 50, Alistair Cameron Crombie, Nancy G. Siraisi, Dept. of History of Smith College, 1987.</ref><ref name="Cosman Jones 2008 p. ">{{cite book | last1=Cosman | first1=Madeleine Pelner | last2=Jones | first2=Linda Gale | title=Handbook to Life in the Medieval World | date=2008 | isbn=978-0-8160-4887-8 |lccn=2007000887 |oclc=77830539 |ol=11359718M |publisher=Facts On File, Infobase Publishing |volume=2 |page=202}}</ref> Waxes are used to make [[waxed paper]], impregnating and [[coated paper|coating paper]] and card to waterproof it or make it resistant to staining, or to modify its surface properties. Waxes are also used in [[shoe polish]]es, [[wood polish]]es, and automotive polishes, as [[mold release agent]]s in [[mold making]], as a coating for many [[cheese]]s, and to [[waterproof]] leather and fabric. Wax has been used since antiquity as a temporary, removable model in [[lost-wax casting]] of [[gold]], [[silver]] and other materials.

Wax with colorful pigments added has been used as a medium in [[encaustic painting]], and is used today in the manufacture of [[crayon]]s, [[Grease pencil|china markers]] and colored [[pencil]]s. [[Carbon paper]], used for making duplicate [[typewriter|typewritten]] documents was coated with [[carbon black]] suspended in wax, typically [[montan wax]], but has largely been superseded by [[photocopier]]s and [[computer printer]]s. In another context, [[lipstick]] and [[mascara]] are blends of various fats and waxes colored with pigments, and both [[beeswax]] and [[lanolin]] are used in other [[cosmetics]]. [[Ski wax]] is used in [[skiing]] and [[snowboarding]]. Also, the sports of surfing and [[skateboarding]]<ref>{{Cite web|title=How To Make Skateboard Wax: A Home DIY Guide|url= https://blackspell.co.uk/how-to-make-skateboard-wax/|access-date=2021-09-22|website=www.blackspell.co.uk|date= 28 July 2021}}</ref> often use wax to enhance the performance.

Some waxes are considered food-safe and are used to coat wooden cutting boards and other items that come into contact with food. Beeswax or coloured synthetic wax is used to decorate [[Easter egg]]s in Romania, Ukraine, Poland, Lithuania and the Czech Republic. [[Paraffin wax]] is used in making chocolate covered sweets.

Wax is also used in [[wax bullet]]s, which are used as simulation aids, and for [[Wax sculpture|wax sculpturing]].

== Specific examples ==

=== Animal waxes ===
* [[Beeswax]] – produced by [[honey bee]]s
* [[Chinese wax]] – produced by the [[scale insect]] ''Ceroplastes ceriferus''
* [[Lanolin]] (wool wax) – from the [[sebaceous gland]]s of [[sheep]]
* [[Shellac]] wax – from the [[lac insect]] ''[[Kerria lacca]]''
* [[Spermaceti]] – from the head cavities and blubber of the [[sperm whale]]

=== Vegetable waxes ===<!-- This section is linked from [[Saccharomyces cerevisiae]] -->
* [[Bayberry wax]] – from the [[epicuticular wax|surface wax]] of the [[drupe|fruits]] of the bayberry shrub, ''[[Myrica faya]]'' or sister species ''[[Myrica cerifera]]'' or ''[[Myrica pensylvanica]]''
* [[Candelilla wax]] – from the Mexican shrubs ''[[Euphorbia cerifera]]'' and ''[[Euphorbia antisyphilitica]]''
* [[Carnauba wax]] – from the leaves of the carnauba palm, ''[[Copernicia cerifera]]''
* [[Castor wax]] – catalytically hydrogenated [[castor oil]]
* Esparto wax – a byproduct of making paper from [[esparto grass]] (''Macrochloa tenacissima'')
* [[Japan wax]] – a vegetable [[triglyceride]] (not a true wax), from the berries of ''Rhus'' and ''Toxicodendron'' species
* [[Jojoba oil]] – a liquid [[wax ester]], from the seed of ''Simmondsia chinensis''.
* [[Ouricury wax]] – from the Brazilian feather palm, ''[[Syagrus coronata]]''.
* [[Rice bran wax]] – obtained from [[rice]] [[bran]] (''Oryza sativa'')
* [[Soy wax]] – from soybean oil
* [[Tallow tree]] wax – from the seeds of the tallow tree ''Triadica sebifera''.

=== Mineral waxes ===
* [[Ceresin]] waxes
* [[Montan wax]] – extracted from [[lignite]] and [[brown coal]]
* [[Ozocerite]] – found in lignite beds
* [[Peat wax]]es

=== Petroleum waxes ===
* [[Paraffin wax]] – made of long-chain [[alkane]] [[hydrocarbon]]s
* [[Microcrystalline wax]] – with very fine crystalline structure

== See also ==
* [[Slip melting point]]  
* [[Wax acid]]
* [[Wax argument]], or the "ball of wax example", is a thought experiment originally articulated by Renė Descartes.

== References ==

{{Reflist|30em}}

== External links ==
{{commons category|Wax}}
* [http://www.cyberlipid.org/wax/wax0001.htm Waxes] {{Webarchive|url=https://web.archive.org/web/20161202062014/http://www.cyberlipid.org/wax/wax0001.htm |date=2016-12-02 }}

{{E number infobox 900-909}}
{{Non-timber forest products}}

{{Authority control}}

[[Category:Waxes| ]]
[[Category:Petroleum products]]
[[Category:Plant products]]
[[Category:Animal products]]
[[Category:Lipids]]
[[Category:Esters]]
[[Category:Soft matter]]