Editing Nitrocellulose (section)

=== Early work on nitration of cellulose ===
[[File:Nitrocellulose hexanitrate.jpg|thumb|Pure nitrocellulose]]
[[File:Workman operating a guncotton press behind protective rope screen.tiff| thumb|right |Workman operating a guncotton press behind a protective rope screen, 1909]]
[[File:Nitrocellulose 02.ogv|thumb|Deflagration test of nitrocellulose in slow motion]]
In 1832 [[Henri Braconnot]] discovered that nitric acid, when combined with starch or wood fibers, would produce a lightweight combustible [[explosive]] material, which he named ''xyloïdine''.<ref>{{cite journal | first = Henri | last = Braconnot | author-link = Henri Braconnot | date = 1833 | url = https://books.google.com/books?id=X5c5AAAAcAAJ&pg=PA290| title = De la transformation de plusieurs substances végétales en un principe nouveau | trans-title= On the transformation of several vegetable substances into a new substance | journal = Annales de Chimie et de Physique | volume = 52 | pages = 290–294 | quote = On page 293, Braconnot names nitrocellulose ''xyloïdine''}}</ref> A few years later in 1838, another French chemist, [[Théophile-Jules Pelouze]] (teacher of [[Ascanio Sobrero]] and [[Alfred Nobel]]), treated paper and cardboard in the same way.<ref>{{cite journal|first=Théophile-Jules|last=Pelouze|author-link=Théophile-Jules Pelouze|date=1838|url=http://gallica.bnf.fr/ark:/12148/bpt6k29662/f713.image.langEN|title=Sur les produits de l'action de l'acide nitrique concentré sur l'amidon et le ligneux|trans-title=On the products of the action of concentrated nitric acid on starch and wood|journal=Comptes Rendus|volume=7|pages=713–715}}</ref> [[Jean-Baptiste Dumas]] obtained a similar material, which he called ''nitramidine''.<ref>{{cite book|first=Jean-Baptiste|last=Dumas|author-link=Jean-Baptiste Dumas|title=Traité de Chimie Appliquée aux Arts|location=Paris|publisher=Bechet Jeune|date=1843|volume=6|url=https://books.google.com/books?id=fEo1AAAAMAAJ&pg=PA90|page=90|quote=''Il y a quelques années, M. Braconnot reconnut que l'acide nitrique concentré, convertit l'amidon, le ligneux, la cellulose, et quelques autres substances en un matière qu'il nomma xyloïdine, et que j'appellerai nitramidine.'' [Some years ago, Mr. Braconnot recognized that concentrated nitric acid converted starch, wood, cellulose, and some other substances into a material that he called xyloïdine, and that I will call nitramidine.]}}</ref>

====Guncotton====
Around 1846 [[Christian Friedrich Schönbein]], a German-Swiss chemist, discovered a more practical formulation.<ref>Schönbein first communicated his discovery to the [[:de:Naturforschende Gesellschaft in Basel|Naturforschende Gesellschaft]] of [[Basel]], Switzerland on March 11, 1846:
* {{cite journal|last=Schönbein|first=Christian Friedrich|author-link=Christian Friedrich Schönbein|date=1846-03-11|url=https://books.google.com/books?id=TSVJAAAAcAAJ&pg=PA26|title=Notiz über eine Veränderung der Pflanzenfaser und einiger andern organischen Substanzen|trans-title=Notice on a change of plant fibers and some other organic substances|journal=Bericht über die Verhandlungen der Naturforschenden Gesellschaft in Basel|volume=7|pages=26–27}}
* {{cite journal|last=Schönbein|first=Christian Friedrich|author-link=Christian Friedrich Schönbein|date=1846-05-27|url=https://books.google.com/books?id=TSVJAAAAcAAJ&pg=PA27|title=Ueber Schiesswolle|trans-title=On guncotton|journal=Bericht über die Verhandlungen der Naturforschenden Gesellschaft in Basel|volume=7|page=27}}
In a letter, he subsequently communicated his discovery to the [[French Academy of Sciences]]:
* {{cite journal|last=Schönbein|first=Christian Friedrich|author-link=Christian Friedrich Schönbein|date=1846|url=http://gallica.bnf.fr/ark:/12148/bpt6k2980r/f682.image.langEN|title=Lettre de M. Schoenbein à M. Dumas|journal=Comptes Rendus|volume=23|pages=678–679}}</ref> As he was working in the kitchen of his home in [[Basel]], he spilled a mixture of [[nitric acid]] (HNO<sub>3</sub>) and [[sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>) on the kitchen table. He reached for the nearest cloth, a cotton apron, and wiped it up. He hung the apron on the stove door to dry, and as soon as it was dry, a flash occurred as the apron ignited. His preparation method was the first to be widely used. The method was to immerse one part of fine [[cotton]] in 15 parts of an equal blend of sulfuric acid and nitric acid. After two minutes, the cotton was removed and washed in cold water to set the [[esterification]] level and to remove all acid residue. The cotton was then slowly dried at a temperature below 40&nbsp;°C (104&nbsp;°F). Schönbein collaborated with the Frankfurt professor [[Rudolf Christian Böttger]], who had discovered the process independently in the same year.

By coincidence, a third chemist, the [[Braunschweig|Brunswick]] professor F. J. Otto had also produced guncotton in 1846 and was the first to publish the process, much to the disappointment of Schönbein and Böttger.<ref>''Itzehoer Wochenblatt'', 29 October 1846, col. 1626ff.</ref>{{full citation needed|date=March 2018}}

The patent rights for the manufacture of guncotton were obtained by John Hall & Son in 1846, and industrial manufacture of the explosive began at a purpose-built factory at [[Faversham explosives industry|Marsh Works]] in [[Faversham, Kent]], a year later. The manufacturing process was not properly understood and  few safety measures were put in place. A serious explosion in July that killed almost two dozen workers resulted in the immediate closure of the plant. Guncotton manufacture ceased for over 15 years until a safer procedure could be developed.<ref>{{cite book|url=https://books.google.com/books?id=vGEGzWqfAtgC|title=Gunpowder: An Explosive History&nbsp;– from the Alchemists of China to the Battlefields of Europe|first=Clive|last=Ponting|year=2011|publisher=Random House|isbn=9781448128112}}</ref>

The British chemist [[Frederick Augustus Abel]] developed the first safe process for guncotton manufacture, which he patented in 1865. The washing and drying times of the nitrocellulose were both extended to 48 hours and repeated eight times over. The acid mixture was changed to two parts sulfuric acid to one part nitric. [[Nitration]] can be controlled by adjusting acid concentrations and reaction temperature. Nitrocellulose is soluble in a mixture of [[ethanol]] and ether until nitrogen concentration exceeds 12%. Soluble nitrocellulose, or a solution thereof, is sometimes called [[collodion]].<ref name="brown">{{cite book|last=Brown|first=G.&nbsp;I.|date=1998|title=The Big Bang: A History of Explosives|publisher=Sutton Publishing|page=[https://archive.org/details/bigbanghistoryof00brow/page/132 132]|isbn=978-0-7509-1878-7|url-access=registration|url=https://archive.org/details/bigbanghistoryof00brow/page/132}}</ref>

Guncotton containing more than 13% nitrogen (sometimes called insoluble nitrocellulose) was prepared by prolonged exposure to hot, concentrated acids<ref name="brown"/> for limited use as a blasting explosive or for [[warhead]]s of underwater weapons such as [[naval mine]]s and [[torpedo]]es.<ref name="naval"/> Safe and sustained production of guncotton began at the [[Waltham Abbey Royal Gunpowder Mills]] in the 1860s, and the material rapidly became the dominant explosive, becoming the standard for military warheads, although it remained too potent to be used as a propellant. More-stable and slower-burning collodion mixtures were eventually prepared using less concentrated acids at lower temperatures for [[smokeless powder]] in [[firearm]]s. The first practical smokeless powder made from nitrocellulose, for firearms and artillery ammunition, was invented by French chemist [[Paul Vieille]] in 1884.

[[Jules Verne]] viewed the development of guncotton with optimism. He referred to the substance several times in his novels. His adventurers carried firearms employing this substance. In his ''[[From the Earth to the Moon]]'', guncotton was used to launch a projectile into space.

Because of their fluffy and nearly white appearance, nitrocellulose products are often referred to as cottons, e.g. lacquer cotton, celluloid cotton, and gun cotton.<ref name=Ull/>

Guncotton was originally made from cotton (as the source of cellulose) but contemporary methods use highly processed cellulose from [[wood pulp]]. While guncotton is dangerous to store, the hazards it presents can be minimized by storing it dampened with various liquids, such as alcohol. For this reason, accounts of guncotton usage dating from the early 20th century refer to "wet guncotton."
[[File:Gws-jamtinbomb.jpg|thumb|[[Jam tin grenade]]s were made in [[World War I]] using gun cotton]]
The power of guncotton made it suitable for blasting. As a projectile driver, it had around six times the gas generation of an equal volume of [[black powder]] and produced less smoke and less heating.

Artillery shells filled with gun cotton were widely used during the [[American Civil War]], and its use was one of the reasons the conflict was seen as the "first modern war."<ref>{{cite web |url=http://www.bbc.co.uk/history/worldwars/war_tech_gallery_04.shtml |title=Explosives in War |last=Bennett |first=Matthew |date=17 February 2011 |website=BBC History |publisher= |access-date=9 April 2021 |quote=}}</ref> Fired from [[Rifled breech loader|breech-loading artillery]], such high explosive shells could cause greater damage than previous solid [[round shot]].

During [[World War I|the first World War]], British authorities were slow to introduce new [[grenade]]s, with soldiers at the front improvising by filling ration [[Jam tin grenade|tin cans with gun cotton]], scrap and a basic fuse.<ref>{{cite encyclopedia |last=Westwell |first=Ian |author-link= |editor-last= |editor-first= |editor-link= |encyclopedia= |title=The Ultimate Illustrated History of World War I |trans-title= |language=en |edition= |year=2008 |publisher=Hermes House |series= |volume= |location= |id= |isbn=978-0-681-54134-4 |issn= |page=131 |url-status= |quote= }}</ref>

Further research indicated the importance of washing the acidified cotton. Unwashed nitrocellulose (sometimes called pyrocellulose) may spontaneously ignite and explode at [[room temperature]], as the evaporation of water results in the concentration of unreacted acid.<ref name="naval">{{cite book|last1=Fairfield|first1=A.&nbsp;P.|author2=CDR&nbsp;USN|title=Naval Ordnance|publisher=Lord Baltimore Press|date=1921|pages=28–31}}</ref>