What is Pitch (resin)?
'''Pitch''' is a type of [[polymer]]. It can be natural or man-made. It can be gotten from [[petroleum]], [[Tar|coal tar]], or [[Plant|plants]]. Pitch made from plants is also called resin. Some things that are made from plant resin are also known as rosin.<ref>{{Cite web|title=COAL-TAR PITCH, HIGH TEMPERATURE|url=http://echa.europa.eu/documents/10162/13630/trd_rar_env_netherlands_pitch_en.pdf|url-status=dead|access-date=2021-05-05|archive-date=2021-05-05|archive-url=https://web.archive.org/web/20210505095450/https://echa.europa.eu/documents/10162/13630/trd_rar_env_netherlands_pitch_en.pdf}}</ref> ==Properties== Pitch is very viscous. It has a [[viscosity]] approximately 230 billion times that of [[water]]. An experiment was done by the University of Queensland. The experiment is called the pitch drop experiment. In the experiment, pitch was put in a [[glass]] [[funnel]] and allowed to slowly drip out.<ref>{{Cite web|date=2016-01-06|title=Pitch Drop experiment|url=https://smp.uq.edu.au/pitch-drop-experiment|access-date=2021-05-05|website=smp.uq.edu.au|language=en}}</ref> Since the pitch was allowed to start dripping in 1930, only nine drops have fallen. The eighth drop fell on 28 November 2000, and the ninth drop fell on 17 April 2014.<ref>{{Cite web|last=Biever|first=Lisa Grossman and Celeste|title=Longest experiment sees pitch drop after 84-year wait|url=https://www.newscientist.com/article/dn25441-longest-experiment-sees-pitch-drop-after-84-year-wait/|access-date=2021-05-05|website=New Scientist|language=en-US}}</ref> ==Uses== Pitch was used to help [[caulk]] the [[seam]]s of wooden sailing vessels. It was used to cover [[earthenware]] containers to preserve wine. Pitch may also be used to make wooden containers [[waterproofing|waterproof]]. It is also used in making torches that use fire. It is used for polishing high-quality optical lenses and [[mirrors]]. Some types of pitch is used in making jewellery. ==References== {{Reflist}} [[Category:Polymers]]