Wikipedia:WikiProject Chemicals/Chembox validation/VerifiedDataSandbox and Poly(methyl methacrylate): Difference between pages

{{Short description|Transparent thermoplastic, commonly called acrylic}}

{{About|the transparent plastic sometimes called acrylic glass|the glass/plastic laminate often called "safety glass"|Laminated glass|the neurotoxic designer drug PMMA|para-Methoxy-N-methylamphetamine|other uses|Acrylic (disambiguation)}}

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| OtherNames =

Poly(methyl methacrylate)

PMMA

methacrylate resin

| Perspex

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| Formula = {{chem2|([[carbon|C]]5[[hydrogen|H]]8[[oxygen|O]]2)_{''n''}|}}

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| Density = 1.18g/cmsup3<ref name=p1/>

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| RefractIndex = 1. at .nm<ref name=refr/>

| MagSus = −9.06×10{{sup|−6}} (SI, 22{{nbsp}}°C)<ref>{{cite journal |last1=Wapler |first1=M. C. |last2=Leupold |first2=J. |last3=Dragonu |first3=I. |last4=von Elverfeldt |first4=D. |last5=Zaitsev |first5=M. |last6=Wallrabe |first6=U. |title=Magnetic properties of materials for MR engineering, micro-MR and beyond |journal=JMR |date=2014 |volume=242 |issue=2014 |pages=233–242 |doi=10.1016/j.jmr.2014.02.005 |pmid=24705364 |arxiv=1403.4760 |bibcode=2014JMagR.242..233W |s2cid=11545416}}</ref>

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[[File:Lichtenberg figure in block of Plexiglas.jpg|thumb|right|[[Lichtenberg figure]]: high-voltage dielectric breakdown in an acrylic polymer block]]

'''Poly'''('''methyl methacrylate''') ('''PMMA''') is the [[list of synthetic polymers|synthetic polymer]] derived from [[methyl methacrylate]]. It is used as an [[engineering plastic]], and it is a [[transparency (optics)|transparent]] [[thermoplastic]]. PMMA is also known as '''acrylic''', '''acrylic glass''', as well as by the trade names and brands '''Crylux''', '''Hesalite''', '''Plexiglas''', '''Acrylite''', '''Lucite''', and '''Perspex''', among several others ([[#Names|see below]]). This plastic is often used in sheet form as a lightweight or shatter-resistant alternative to [[soda-lime glass|glass]]. It can also be used as a casting resin, in inks and coatings, and for many other purposes.

It is often technically classified as a type of [[glass]], in that it is a non-crystalline vitreous substance—hence its occasional historic designation as ''acrylic glass''.

==History==

The first acrylic acid was created in 1843. [[Methacrylic acid]], derived from [[acrylic acid]], was formulated in 1865. The reaction between methacrylic acid and [[methanol]] results in the ester methyl methacrylate.

It was developed in 1928 in several different laboratories by many chemists, such as William R. Conn, [[Otto Röhm]], and Walter Bauer, and first brought to market in 1933 by German ''Röhm & Haas AG'' (as of January 2019, part of [[Evonik Industries]]) and its partner and former U.S. affiliate [[Rohm and Haas|Rohm and Haas Company]] under the [[trademark]] Plexiglas.<ref>[https://history.evonik.com/sites/geschichte/de/erfindungen/plexiglas/ Plexiglas history by Evonik] (in German).</ref>

Polymethyl methacrylate was discovered in the early 1930s by British chemists Rowland Hill and John Crawford at [[Imperial Chemical Industries]] (ICI) in the United Kingdom.{{citation needed|date=October 2019}} ICI registered the product under the trademark Perspex. About the same time, chemist and industrialist [[Otto Röhm]] of Röhm and Haas AG in Germany attempted to produce safety glass by polymerizing methyl methacrylate between two layers of glass. The polymer separated from the glass as a clear plastic sheet, which Röhm gave the trademarked name Plexiglas in 1933.<ref>{{cite web |title=DPMAregister {{!}} Marken - Registerauskunft |url=https://register.dpma.de/DPMAregister/marke/register/461639/DE |access-date=2021-09-29 |website=register.dpma.de}}</ref> Both Perspex and Plexiglas were commercialized in the late 1930s. In the United States, E.I. du Pont de Nemours & Company (now DuPont Company) subsequently introduced its own product under the trademark Lucite. In 1936 ICI Acrylics (now Lucite International) began the first commercially viable production of acrylic safety glass. During [[World War II]] both Allied and Axis forces used acrylic glass for submarine periscopes and aircraft windscreen, canopies, and gun turrets. Scraps of acrylic were also used to made clear pistol grips for the M1911A1 pistol or clear handle grips for the M1 bayonet or theater knifes so that soldiers could put small photos of loved ones or pin-up girls' pictures inside. They were called "Sweetheart Grips" or "Pin-up Grips". Others were used to make handles for theater knives made from scrap materials and people who made them got artistic or creative.<ref>{{cite book |title=Congressional Record: Proceedings and Debates of the 77th Congress First Session |date=1941 |publisher=U.S. Government Printing Office |location=Washington, D.C. |pages=A2300–A2302 |edition=Volume 87, Part 11 |url=https://books.google.com/books?id=TXBvFGzeUp4C&dq=plexiglas+war&pg=SL1-PA2301 |access-date=3 August 2020}}</ref> Civilian applications followed after the war.<ref>{{cite web |url=https://www.britannica.com/science/polymethyl-methacrylate |title=Polymethyl methacrylate &#124; chemical compound |access-date=2017-05-22 |url-status=live |archive-url=https://web.archive.org/web/20171031004312/https://www.britannica.com/science/polymethyl-methacrylate |archive-date=2017-10-31}}</ref>

== Names ==

Common orthographic stylings include ''polymethyl methacrylate''<ref name="Dorlands">{{citation |title=polymethyl methacrylate |work=Dorland's Illustrated Medical Dictionary |publisher=[[Elsevier]] |url=https://www.dorlandsonline.com/dorland/definition?id=100085009&searchterm=polymethyl%20methacrylate |url-access=subscription}}</ref><ref name="MW_Collegiate">{{cite Merriam-Webster |polymethyl methacrylate}}</ref> and ''polymethylmethacrylate''. The full IUPAC chemical name is poly(methyl 2-methylprop{{strong|en}}oate). (It is a common mistake to use "an" instead of "en".)

Although PMMA is often called simply "acrylic", ''[[acrylate polymer|acrylic]]'' can also refer to other polymers or copolymers containing [[polyacrylonitrile]]. Notable trade names and brands include Acrylite, Altuglas,<ref name="Platt2003">{{cite book |author=David K. Platt |url=https://books.google.com/books?id=ajVlFikzvA8C&pg=PA170 |title=Engineering and High Performance Plastics Market Report: A Rapra Market Report |date=1 January 2003 |publisher=Smithers Rapra |isbn=978-1-85957-380-8 |page=170 |archive-url=https://web.archive.org/web/20160421171832/https://books.google.com/books?id=ajVlFikzvA8C&pg=PA170 |archive-date=21 April 2016 |url-status=live}}</ref> Astariglas, Cho Chen, Crystallite, Cyrolite,<ref name="HarperPetrie2003">{{cite book |author1=Charles A. Harper |url=https://books.google.com/books?id=oe5YJmRmxQMC&pg=PA9 |title=Plastics Materials and Processes: A Concise Encyclopedia |author2=Edward M. Petrie |date=10 October 2003 |publisher=John Wiley & Sons |isbn=978-0-471-45920-0 |page=9 |archive-url=https://web.archive.org/web/20160420235832/https://books.google.com/books?id=oe5YJmRmxQMC&pg=PA9 |archive-date=20 April 2016 |url-status=live}}</ref> Hesalite (when used in [[Omega SA|Omega watches]]), Lucite,<ref name="tess_lucite">{{cite web |title=Trademark Electronic Search System |page=Search for Registration Number 0350093 |url=http://tmsearch.uspto.gov |website=TESS |publisher=US Patent and Trademark Office |access-date=29 June 2014}}</ref> Optix,<ref name="HarperPetrie2003" /> Oroglas,<ref name="Information1974">{{cite journal |date=13 June 1974 |title=Misused materials stoked Sumerland fire |url=https://books.google.com/books?id=9fCPtxShxY8C&pg=PA684 |url-status=live |journal=New Scientist |publisher=IPC Magazines |volume=62 |issue=902 |page=684 |issn=0262-4079 |archive-url=https://web.archive.org/web/20160421165319/https://books.google.com/books?id=9fCPtxShxY8C&pg=PA684 |archive-date=21 April 2016}}</ref> PerClax, Perspex,<ref name="HarperPetrie2003" /> Plexiglas,<ref name="HarperPetrie2003" /><ref>{{cite web |title=WIPO Global Brand Database |url=http://www.wipo.int/branddb/en/ |url-status=live |archive-url=https://web.archive.org/web/20130121162152/http://wipo.int/branddb/en/ |archive-date=2013-01-21 |access-date=2013-01-25}}</ref> R-Cast, and Sumipex.

PMMA is an economical alternative to [[polycarbonate]] (PC) when [[tensile strength]], [[flexural strength]], [[transparency and translucency|transparency]], polishability, and UV tolerance are more important than [[impact strength]], chemical resistance, and heat resistance. Additionally, PMMA does not contain the potentially harmful [[bisphenol-A]] subunits found in polycarbonate and is a far better choice for laser cutting.<ref>{{cite web |url=https://cpl.org/wp-content/uploads/NEVER-CUT-THESE-MATERIALS.pdf |title=Never cut these materials}}{{failed verification|date=October 2023}}</ref> It is often preferred because of its moderate properties, easy handling and processing, and low cost. Non-modified PMMA behaves in a brittle manner when under load, especially under an [[impact (mechanics)|impact force]], and is more prone to scratching than conventional inorganic glass, but modified PMMA is sometimes able to achieve high scratch and impact resistance.

== Properties ==

[[File:Methyl-methacrylate-skeletal.png|thumb|left|upright=0.5|Skeletal structure of methyl methacrylate, the constituent [[monomer]] of PMMA]]

[[File:Perspex pieces (AM 2007.10.2-2).jpg|thumb|Pieces of Plexiglas taken from the windscreen of a German plane shot down during World War II]]

PMMA is a strong, tough, and lightweight material. It has a [[density]] of 1.17–1.20&nbsp;g/cm{{sup|3}},<ref name=p1/><ref name=p2/> which is less than half that of glass.<ref name=p1>[http://www.makeitfrom.com/material-properties/Polymethylmethacrylate-PMMA-Acrylic Polymethylmethacrylate (PMMA, Acrylic)] {{webarchive|url=https://web.archive.org/web/20150402124133/http://www.makeitfrom.com/material-properties/Polymethylmethacrylate-PMMA-Acrylic |date=2015-04-02}}. Makeitfrom.com. Retrieved 2015-03-23.</ref> It also has good impact strength, higher than both glass and polystyrene, but significantly lower than polycarbonate and some engineered polymers. PMMA ignites at {{cvt|460|C}} and [[combustion|burns]], forming [[carbon dioxide]], [[water]], [[carbon monoxide]], and low-molecular-weight compounds, including [[formaldehyde]].<ref>{{cite journal |id={{INIST|14365060}} |doi=10.1177/073490402762574749 |title=Preliminary Studies on Burning Behavior of Polymethylmethacrylate (PMMA) |year=2002 |last1=Zeng |first1=W. R. |last2=Li |first2=S. F. |last3=Chow |first3=W. K. |journal=Journal of Fire Sciences |volume=20 |issue=4 |pages=297–317|hdl=10397/31946 |s2cid=97589855 |hdl-access=free}}</ref>

PMMA [[transmittance|transmits]] up to 92% of [[visible light]] ({{cvt|3|mm}} thickness),<ref>{{cite book |last1=McKeen |first1=Laurence W. |title=The effect of UV light and weather on plastics and elastomers |date=2019 |publisher=Elsevier |location=Washington, WA |isbn=978-0-1281-6457-0 |page=254 |edition=4th |url=https://app.knovel.com/kn/resources/kpEUVLWP11/toc}}</ref> and gives a reflection of about 4% from each of its surfaces due to its [[refractive index]] (1.4905 at 589.3{{nbsp}}nm).<ref name=refr>[http://refractiveindex.info/?shelf=organic&book=poly%28methyl_methacrylate%29&page=Szczurowski Refractive index and related constants – Poly(methyl methacrylate) (PMMA, Acrylic glass)] {{webarchive|url=https://web.archive.org/web/20141106114447/http://refractiveindex.info/?shelf=organic&book=poly%28methyl_methacrylate%29&page=Szczurowski |date=2014-11-06}}. Refractiveindex.info. Retrieved 2014-10-27.</ref> It filters [[ultraviolet]] (UV) light at wavelengths below about 300 [[nanometre|nm]] (similar to ordinary window glass). Some manufacturers<ref>[http://www.plexiglas.com/acrylicsheet/acrylicsheetfamily#9 Altuglas International Plexiglas UF-3 UF-4 and UF-5 sheets] {{webarchive|url=https://web.archive.org/web/20061117051151/http://www.plexiglas.com/acrylicsheet/acrylicsheetfamily |date=2006-11-17}}. Plexiglas.com. Retrieved 2012-05-09.</ref> add coatings or additives to PMMA to improve absorption in the 300–400&nbsp;nm range. PMMA passes [[infrared]] light of up to 2,800&nbsp;nm and blocks IR of longer [[wavelength]]s up to 25,000&nbsp;nm. Colored PMMA varieties allow specific IR wavelengths to pass while blocking [[visible spectrum|visible light]] (for [[remote control]] or heat sensor applications, for example).

PMMA swells and dissolves in many organic [[solvent]]s; it also has poor resistance to many other chemicals due to its easily [[hydrolysis|hydrolyzed]] [[ester]] groups. Nevertheless, its environmental stability is superior to most other plastics such as polystyrene and polyethylene, and therefore it is often the material of choice for outdoor applications.<ref>Myer Ezrin [https://books.google.com/books?id=baWyaC3w3hcC&pg=PA168 ''Plastics Failure Guide: Cause and Prevention''] {{webarchive|url=https://web.archive.org/web/20160421165428/https://books.google.com/books?id=baWyaC3w3hcC&pg=PA168 |date=2016-04-21}}, Hanser Verlag, 1996 {{ISBN|1-56990-184-8}}, p. 168</ref>

PMMA has a maximum water absorption ratio of 0.3–0.4% by weight.<ref name=p2>[http://www.matbase.com/material/polymers/commodity/pmma/properties DATA TABLE FOR: Polymers: Commodity Polymers: PMMA] {{webarchive|url=https://web.archive.org/web/20071213163116/http://www.matbase.com/material/polymers/commodity/pmma/properties |date=2007-12-13}}. Matbase.com. Retrieved 2012-05-09.</ref> Tensile strength decreases with increased water absorption.<ref>{{cite journal |doi=10.1557/PROC-875-O12.7 |first1=Chiemi |last1=Ishiyama |first2=Yoshito |last2=Yamamoto |first3=Yakichi |last3=Higo |year=2005 |title=Effects of Humidity History on the Tensile Deformation Behaviour of Poly(methyl–methacrylate) (PMMA) Films |journal=MRS Proceedings |volume=875 |editor1-first=T. |editor1-last=Buchheit |editor2-first=A. |editor2-last=Minor |editor3-first=R. |editor3-last=Spolenak |editor4-first=K. |display-editors=3 |editor4-last=Takashima |pages=O12.7}}</ref> Its [[coefficient of thermal expansion]] is relatively high at (5–10)×10{{sup|−5}}&nbsp;°C{{sup|−1}}.<ref>{{cite web |title=Tangram Technology Ltd. – Polymer Data File – PMMA |url=http://www.tangram.co.uk/TI-Polymer-PMMA.html |url-status=live |archive-url=https://web.archive.org/web/20100421184714/http://www.tangram.co.uk/TI-Polymer-PMMA.html |archive-date=2010-04-21}}</ref>

The [[Futuro]] house was made of fibreglass-reinforced polyester plastic, polyester-polyurethane, and poly(methylmethacrylate); one of them was found to be degrading by [[cyanobacteria]] and [[Archaea]].<ref>{{cite journal |doi=10.1016/j.tibtech.2006.06.001 |title=Biodeterioration of modern materials in contemporary collections: Can biotechnology help? |year=2006 |last1=Cappitelli |first1=Francesca |last2=Principi |first2=Pamela |last3=Sorlini |first3=Claudia |journal=Trends in Biotechnology |volume=24 |issue=8 |pages=350–4 |pmid=16782219}}</ref><ref>{{cite journal |doi=10.1038/sj.embor.7400844 |title=Saving a fragile legacy. Biotechnology and microbiology are increasingly used to preserve and restore the world's cultural heritage |year=2006 |last1=Rinaldi |first1=Andrea |journal=EMBO Reports |volume=7 |issue=11 |pages=1075–9 |pmid=17077862 |pmc=1679785}}</ref>

PMMA can be joined using [[cyanoacrylate]] cement (commonly known as [[superglue]]), with heat (welding), or by using chlorinated solvents such as [[dichloromethane]] or [[chloroform|trichloromethane]]<ref>[http://www.science-projects.com/Plastics/PlexiglasWork.htm "Working with Plexiglas"] {{webarchive|url=https://web.archive.org/web/20150221110921/http://www.science-projects.com/Plastics/PlexiglasWork.htm |date=2015-02-21}}. ''science-projects.com''.</ref> (chloroform) to dissolve the plastic at the joint, which then fuses and sets, forming an almost invisible [[solvent welding|weld]]. Scratches may easily be removed by polishing or by heating the surface of the material. [[Laser cutting]] may be used to form intricate designs from PMMA sheets. PMMA vaporizes to gaseous compounds (including its monomers) upon laser cutting, so a very clean cut is made, and cutting is performed very easily. However, the pulsed lasercutting introduces high internal stresses, which on exposure to solvents produce undesirable "stress-[[crazing]]" at the cut edge and several millimetres deep. Even ammonium-based glass-cleaner and almost everything short of soap-and-water produces similar undesirable crazing, sometimes over the entire surface of the cut parts, at great distances from the stressed edge.<ref name=hjsandersen>{{cite web |last1=Andersen |first1=Hans J |title=Tensions in acrylics when laser cutting |url=http://www.support.induflex.dk/Plast_Laserskaering_acryl.aspx?Lang=en-GB#lblTensions |access-date=23 December 2014 |url-status=live |archive-url=https://web.archive.org/web/20151208045021/http://www.support.induflex.dk/Plast_Laserskaering_acryl.aspx?Lang=en-GB#lblTensions |archive-date=8 December 2015}}</ref> Annealing the PMMA sheet/parts is therefore an obligatory post-processing step when intending to chemically bond lasercut parts together.

In the majority of applications, PMMA will not shatter. Rather, it breaks into large dull pieces. Since PMMA is softer and more easily scratched than glass, [[anti-scratch coating|scratch-resistant coatings]] are often added to PMMA sheets to protect it (as well as possible other functions).

Pure poly(methyl methacrylate) homopolymer is rarely sold as an end product, since it is not optimized for most applications. Rather, modified formulations with varying amounts of other [[comonomer]]s, additives, and fillers are created for uses where specific properties are required. For example:

* A small amount of acrylate comonomers are routinely used in PMMA grades destined for heat processing, since this stabilizes the polymer to [[depolymerization]] ("unzipping") during processing.

* Comonomers such as [[butyl acrylate]] are often added to improve impact strength.

* Comonomers such as methacrylic acid can be added to increase the glass transition temperature of the polymer for higher temperature use such as in lighting applications.

* [[Plasticizer]]s may be added to improve processing properties, lower the glass transition temperature, improve impact properties, and improve mechanical properties such as elastic modulus <ref>{{cite journal |last1=López |first1=Alejandro |last2=Hoess |first2=Andreas |last3=Thersleff |first3=Thomas |last4=Ott |first4=Marjam |last5=Engqvist |first5=Håkan |last6=Persson |first6=Cecilia |date=2011-01-01 |title=Low-modulus PMMA bone cement modified with castor oil |journal=Bio-Medical Materials and Engineering |language=en |volume=21 |issue=5–6 |pages=323–332 |doi=10.3233/BME-2012-0679 |pmid=22561251 |issn=0959-2989 |doi-access=free}}</ref>

* [[Dye]]s may be added to give color for decorative applications, or to protect against (or filter) UV light.

* [[Filler (materials)|Fillers]] may be substituted to reduce cost.

== Synthesis and processing ==

PMMA is routinely produced by [[emulsion polymerization]], [[solution polymerization]], and [[bulk polymerization]]. Generally, radical initiation is used (including [[living polymerization]] methods), but anionic polymerization of PMMA can also be performed.<ref name=Stickler>{{cite book |doi=10.1002/14356007.a21_473|chapter=Polymethacrylates |title=Ullmann's Encyclopedia of Industrial Chemistry |year=2000 |last1=Stickler |first1=Manfred |last2=Rhein |first2=Thoma |isbn=3527306730 }}</ref>

The [[glass transition temperature]] (''T{{sub|g}}'') of [[tacticity|atactic]] PMMA is {{convert|105|C|F}}. The ''T{{sub|g}}'' values of commercial grades of PMMA range from {{convert|85|to|165|C|F}}; the range is so wide because of the vast number of commercial compositions that are copolymers with co-monomers other than methyl methacrylate. PMMA is thus an organic glass at room temperature; i.e., it is below its ''T{{sub|g}}''. The forming temperature starts at the glass transition temperature and goes up from there.<ref>{{cite book |last=Ashby |first=Michael F. |author-link=Michael F. Ashby |title=Materials Selection in Mechanical Design |url=https://archive.org/details/materialsselecti00ashb_159 |url-access=limited |publisher=Elsevier |year=2005 |edition=3rd |isbn=978-0-7506-6168-3 |page=[https://archive.org/details/materialsselecti00ashb_159/page/n433 519]}}</ref> All common molding processes may be used, including [[injection molding]], [[compression molding]], and [[extrusion]]. The highest quality PMMA sheets are produced by [[cell casting]], but in this case, the polymerization and molding steps occur concurrently. The strength of the material is higher than molding grades owing to its extremely high [[molecular mass]]. [[Rubber toughening]] has been used to increase the toughness of PMMA to overcome its brittle behavior in response to applied loads.

== Applications ==

{{prose|section|date=May 2023}}

[[file:Bathyscaphe Trieste sphere.jpg|thumb|Close-up of pressure sphere of the [[Trieste (bathyscaphe)|bathyscaphe ''Trieste'']], with a single conical window of PMMA set into sphere hull. The very small black circle (smaller than the man's head) is the inner side of the plastic "window", only a few inches in diameter. The larger circular clear black area represents the larger outer side of the thick one-piece plastic cone "window".]]

Being transparent and durable, PMMA is a versatile material and has been used in a wide range of fields and applications such as rear-lights and instrument clusters for vehicles, appliances, and lenses for glasses. PMMA in the form of sheets affords to shatter resistant panels for building windows, skylights, bulletproof security barriers, signs and displays, sanitary ware (bathtubs), LCD screens, furniture and many other applications. It is also used for coating polymers based on MMA provides outstanding stability against environmental conditions with reduced emission of VOC. Methacrylate polymers are used extensively in medical and dental applications where purity and stability are critical to performance.<ref name=Stickler/>

=== Glass substitute ===

[[file:KelpAquarium.jpg|thumb|left|{{convert|10|m|ft|adj=on|sp=us}} deep [[Monterey Bay Aquarium]] tank has acrylic windows up to {{convert|33|cm|in|sp=us}} thick to withstand the [[fluid statics#Hydrostatic pressure|water pressure]].]]

* PMMA is commonly used for constructing residential and commercial [[aquarium]]s. Designers started building large aquariums when poly(methyl methacrylate) could be used. It is less often used in other building types due to incidents such as the [[Summerland disaster]].

* PMMA is used for viewing ports and even complete pressure hulls of submersibles, such as the [[Alicia (submarine)|''Alicia'' submarine]]'s viewing sphere and the window of the [[bathyscaphe Trieste]].

* PMMA is used in the lenses of exterior lights of automobiles.<ref>{{cite book |author=Kutz, Myer |title=Handbook of Materials Selection |url=https://archive.org/details/handbookmaterial00kutz |url-access=limited |publisher=John Wiley & Sons |year=2002 |page=[https://archive.org/details/handbookmaterial00kutz/page/n351 341] |isbn=978-0-471-35924-1}}</ref>

* Spectator protection in [[ice hockey]] rinks is made from PMMA.

* Historically, PMMA was an important improvement in the design of aircraft windows, making possible such designs as the bombardier's transparent nose compartment in the [[Boeing B-17 Flying Fortress]]. Modern aircraft transparencies often use stretched acrylic plies.

* Police vehicles for [[riot control]] often have the regular glass replaced with PMMA to protect the occupants from thrown objects.

* PMMA is an important material in the making of certain lighthouse lenses.<ref>[http://www.terrypepper.com/lights/closeups/illumination/index.htm Terry Pepper, Seeing the Light, Illumination] {{webarchive|url=https://web.archive.org/web/20090123055321/http://www.terrypepper.com/lights/closeups/illumination/index.htm |date=2009-01-23}}. Terrypepper.com. Retrieved 2012-05-09.</ref>

* PMMA was used for the roofing of the compound in the [[Olympiapark, Munich|Olympic Park]] for the [[1972 Summer Olympics]] in Munich. It enabled a light and translucent construction of the structure.<ref>{{cite book |editor=Deplazes, Andrea |title=Constructing Architecture – Materials Processes Structures, A Handbook |publisher=Birkhäuser |year=2013 |isbn=978-3038214526}}</ref>

* PMMA (under the brand name "Lucite") was used for the ceiling of the [[Reliant Astrodome|Houston Astrodome]].

=== Daylight redirection ===

{{Main|Anidolic lighting}}

* Laser cut acrylic panels have been used to redirect sunlight into a [[light tube#Light tube with reflective material|light pipe]] or tubular skylight and, from there, to spread it into a room.<ref>Yeang, Ken. [http://www.trhamzahyeang.com/features/img/Light%20pipe%20paper.pdf Light Pipes: An Innovative Design Device for Bringing Natural Daylight and Illumination into Buildings with Deep Floor Plan] {{webarchive|url=https://web.archive.org/web/20090305001322/http://www.trhamzahyeang.com/features/img/Light%20pipe%20paper.pdf |date=2009-03-05}}, Nomination for the Far East Economic Review Asian Innovation Awards 2003</ref> Their developers Veronica Garcia Hansen, [[Ken Yeang]], and Ian Edmonds were awarded the [[Far Eastern Economic Review#Awards presented by the Review|Far East Economic Review Innovation Award]] in bronze for this technology in 2003.<ref>{{cite web|website = Fresh Innovators|url = http://www.scienceinpublic.com/freshinnovators/2005/Veronica/veronicagarciahansen.htm |title = Lighting up your workplace |archiveurl=https://web.archive.org/web/20050702103235/http://www.scienceinpublic.com/freshinnovators/2005/Veronica/veronicagarciahansen.htm |archive-date=2 July 2005|date = May 9, 2005}}</ref><ref>[http://www.worldcities.com.sg/speaker3.htm#kenneth01 Kenneth Yeang] {{webarchive|url=https://web.archive.org/web/20080925033953/http://www.worldcities.com.sg/speaker3.htm |date=2008-09-25}}, World Cities Summit 2008, June 23–25, 2008, Singapore</ref>

* Attenuation being quite strong for distances over one meter (more than 90% intensity loss for a 3000&nbsp;K source),<ref>{{cite journal |doi=10.1582/LEUKOS.01.04.003 |first1=Victor |last1=Gerchikov |first2=Michele |last2=Mossman |first3=Lorne |last3=Whitehead |year=2005 |title=Modeling Attenuation versus Length in Practical Light Guides |journal=LEUKOS |volume=1 |issue=4 |pages=47–59 |s2cid=220306943}}</ref> acrylic broadband light guides are then dedicated mostly to decorative uses.

* Pairs of acrylic sheets with a layer of microreplicated prisms between the sheets can have reflective and refractive properties that let them redirect part of incoming sunlight in dependence on its [[angle of incidence (optics)|angle of incidence]]. Such panels act as miniature [[architectural light shelf|light shelves]]. Such panels have been commercialized for purposes of [[Daylighting (architecture)|daylighting]], to be used as a [[window]] or a [[canopy (building)|canopy]] such that sunlight descending from the sky is directed to the ceiling or into the room rather than to the floor. This can lead to a higher illumination of the back part of a room, in particular when combined with a white ceiling, while having a slight impact on the view to the outside compared to normal glazing.<ref>[http://www.bendinglight.co.uk/assets/pdf_downloads/How_Serraglaze_Works.pdf How Serraglaze works] {{webarchive|url=https://web.archive.org/web/20090305001319/http://www.bendinglight.co.uk/assets/pdf_downloads/How_Serraglaze_Works.pdf |date=2009-03-05}}. Bendinglight.co.uk. Retrieved 2012-05-09.</ref><ref>[http://www.bdonline.co.uk/story.asp?sectioncode=453&storycode=3088579&c=1 Glaze of light] {{webarchive|url=https://web.archive.org/web/20090110100911/http://www.bdonline.co.uk/story.asp?sectioncode=453&storycode=3088579&c=1 |date=2009-01-10}}, Building Design Online, June 8, 2007</ref>

=== Medicine ===

* PMMA has a good degree of compatibility with human [[tissue (biology)|tissue]], and it is used in the manufacture of rigid [[intraocular lens]]es which are implanted in the [[human eye|eye]] when the original lens has been removed in the treatment of [[cataract]]s. This compatibility was discovered by the English ophthalmologist [[Harold Ridley (ophthalmologist)|Harold Ridley]] in WWII RAF pilots, whose eyes had been riddled with PMMA splinters coming from the side windows of their Supermarine [[Spitfire]] fighters – the plastic scarcely caused any rejection, compared to glass splinters coming from aircraft such as the [[Hawker Hurricane]].<ref>Robert A. Meyers, "Molecular biology and biotechnology: a comprehensive desk reference", Wiley-VCH, 1995, p. 722 {{ISBN|1-56081-925-1}}</ref> Ridley had a lens manufactured by the Rayner company (Brighton & Hove, East Sussex) made from Perspex polymerised by ICI. On 29 November 1949 at St Thomas' Hospital, London, Ridley implanted the first intraocular lens at St Thomas's Hospital in London.<ref>{{cite book |last=Apple |first=David J |title=Sir Harold Ridely and His Fight for Sight: He Changed the World So That We May Better See It |year=2006 |publisher=Slack |location=Thorofare NJ USA |isbn=978-1-55642-786-2}}</ref>

In particular, acrylic-type lenses are useful for cataract surgery in patients that have recurrent ocular inflammation (uveitis), as acrylic material induces less inflammation.

* [[Glasses|Eyeglass]] lenses are commonly made from PMMA.

* Historically, hard [[contact lens]]es were frequently made of this material. Soft contact lenses are often made of a related polymer, where acrylate monomers containing one or more [[hydroxyl|hydroxyl group]]s make them [[hydrophile|hydrophilic]].

* In [[orthopedic surgery]], PMMA [[bone cement]] is used to affix implants and to remodel lost bone.<ref>{{Cite journal |last1=Carroll |first1=Gregory T. |last2=Kirschman |first2=David L. |date=2022-07-13 |title=A portable negative pressure unit reduces bone cement fumes in a simulated operating room |journal=Scientific Reports |language=en |volume=12 |issue=1 |page=11890 |doi=10.1038/s41598-022-16227-x |issn=2045-2322 |pmc=9279392 |pmid=35831355|bibcode=2022NatSR..1211890C }}</ref> It is supplied as a powder with liquid methyl methacrylate (MMA). Although PMMA is biologically compatible, MMA is considered to be an irritant and a possible [[carcinogen]]. PMMA has also been linked to [[cardiopulmonary resuscitation|cardiopulmonary]] events in the operating room due to [[hypotension]].<ref>{{cite journal |first1=Timothy J. |last1=Kaufmann |first2=Mary E. |last2=Jensen |first3=Gabriele |last3=Ford |first4=Lena L. |last4=Gill |first5=William F. |last5=Marx |first6=David F. |last6=Kallmes |title=Cardiovascular Effects of Polymethylmethacrylate Use in Percutaneous Vertebroplasty |journal=American Journal of Neuroradiology |pmid=11950651 |url=http://www.ajnr.org/cgi/pmidlookup?view=long&pmid=11950651 |date=2002-04-01 |volume=23 |issue=4 |pages=601–4 |pmc=7975098}}</ref> Bone cement acts like a [[grout]] and not so much like a glue in [[arthroplasty]]. Although sticky, it does not bond to either the bone or the implant; rather, it primarily fills the spaces between the prosthesis and the bone preventing motion. A disadvantage of this bone cement is that it heats up to {{Convert|82.5|C|F}} while setting that may cause thermal necrosis of neighboring tissue. A careful balance of initiators and monomers is needed to reduce the rate of polymerization, and thus the heat generated.

* In [[plastic surgery|cosmetic surgery]], tiny PMMA microspheres suspended in some biological fluid are injected as a soft-tissue filler under the skin to reduce wrinkles or scars permanently.<ref>{{cite web |title=Filling in Wrinkles Safely |url=https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm049349.htm |publisher=U.S. Food and Drug Administration |access-date=8 December 2015 |date=February 28, 2015 |url-status=live |archive-url=https://web.archive.org/web/20151121160450/https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm049349.htm |archive-date=21 November 2015}}</ref> PMMA as a soft-tissue filler was widely used in the beginning of the century to restore volume in patients with HIV-related facial wasting. PMMA is used illegally to shape muscles by some [[bodybuilding|bodybuilders]].

* [[Plombage]] is an outdated treatment of [[tuberculosis]] where the [[pleural]] space around an infected [[lung]] was filled with PMMA balls, in order to compress and collapse the affected lung.

* Emerging biotechnology and [[medical research|biomedical research]] use PMMA to create [[microfluidics|microfluidic]] [[lab-on-a-chip]] devices, which require 100 micrometre-wide geometries for routing liquids. These small geometries are amenable to using PMMA in a [[biochip]] fabrication process and offers moderate [[biocompatibility]].

* [[Bioprocess]] [[chromatography]] columns use cast acrylic tubes as an alternative to glass and stainless steel. These are pressure rated and satisfy stringent requirements of materials for [[biocompatibility]], toxicity, and extractables.

=== Dentistry ===

Due to its aforementioned biocompatibility, poly(methyl methacrylate) is a commonly used material in modern dentistry, particularly in the fabrication of dental prosthetics, artificial teeth, and orthodontic appliances.

* Acrylic prosthetic construction: Pre-polymerized, powdered PMMA spheres are mixed with a Methyl Methacrylate liquid monomer, Benzoyl Peroxide (initiator), and NN-Dimethyl-P-Toluidine (accelerator), and placed under heat and pressure to produce a hardened polymerized PMMA structure. Through the use of injection molding techniques, wax based designs with artificial teeth set in predetermined positions built on gypsum stone models of patients' mouths can be converted into functional prosthetics used to replace missing dentition. PMMA polymer and methyl methacrylate monomer mix is then injected into a flask containing a gypsum mold of the previously designed prosthesis, and placed under heat to initiate polymerization process. Pressure is used during the curing process to minimize polymerization shrinkage, ensuring an accurate fit of the prosthesis. Though other methods of polymerizing PMMA for prosthetic fabrication exist, such as chemical and microwave resin activation, the previously described heat-activated resin polymerization technique is the most commonly used due to its cost effectiveness and minimal polymerization shrinkage.

* Artificial teeth: While denture teeth can be made of several different materials, PMMA is a material of choice for the manufacturing of artificial teeth used in dental prosthetics. Mechanical properties of the material allow for heightened control of aesthetics, easy surface adjustments, decreased risk of fracture when in function in the oral cavity, and minimal wear against opposing teeth. Additionally, since the bases of dental prosthetics are often constructed using PMMA, adherence of PMMA denture teeth to PMMA denture bases is unparalleled, leading to the construction of a strong and durable prosthetic.<ref>{{cite book |title=Prosthodontic treatment for edentulous patients: complete dentures and implant-supported prostheses |date=2013 |publisher=Elsevier Mosby |last1=Zarb |first1= George Albert |isbn=9780323078443 |edition=13th |location=St. Louis, Mo. |oclc=773020864}}</ref>

=== Art and aesthetics ===

[[File:Lexus LF-A Crystallised Wind.jpg|thumb|left|[[Lexus LFA#Sculpture models|Lexus]] Perspex car sculpture]]

[[File:Maylan-interior-design-neue-wiener-werkstaette-interlux-roehm- evonik- indeustries-contemporary-light-art-sedan-chair-seats-manfred-kielnhofer-illumination-auchtion.jpg|thumb|PMMA art by [[Manfred Kielnhofer]]]]

[[File:Kawai CR-40A.jpg|upright|thumb|left|[[Kawai (company)|Kawai]] acrylic grand piano]]

[[File:"Rootbeer" Lucite Bangle Bracelet - DPLA - 72b817c152132c7bf0d40c71240c4f1e.jpg|thumb|right|Lucite Bangle Bracelet]]

* [[Acrylic paint]] essentially consists of PMMA suspended in water; however since PMMA is [[hydrophobe|hydrophobic]], a substance with both hydrophobic and hydrophilic groups needs to be added to facilitate the [[suspension (chemistry)|suspension]].

* Modern [[furniture]] makers, especially in the 1960s and 1970s, seeking to give their products a space age aesthetic, incorporated Lucite and other PMMA products into their designs, especially office chairs. Many other products (for example, guitars) are sometimes made with acrylic glass to make the commonly opaque objects translucent.

* Perspex has been used as a surface to paint on, for example by [[Salvador Dalí]].

* [[Diasec]] is a process which uses acrylic glass as a substitute for normal glass in [[picture frame]]s. This is done for its relatively low cost, light weight, shatter-resistance, aesthetics and because it can be ordered in larger sizes than standard [[picture framing glass]].

* As early as 1939, Los Angeles-based Dutch sculptor [[Jan de Swart|Jan De Swart]] experimented with samples of Lucite sent to him by DuPont; De Swart created tools to work the Lucite for sculpture and mixed chemicals to bring about certain effects of color and refraction.<ref>de Swart, Ursula. My Life with Jan. Collection of Jock de Swart, Durango, CO</ref>

* From approximately the 1960s onward, sculptors and glass artists such as [[Jan Kubíček]], [[Leroy Lamis]], and [[Frederick Hart (sculptor)|Frederick Hart]] began using acrylics, especially taking advantage of the material's flexibility, light weight, cost and its capacity to refract and filter light.

* In the 1950s and 1960s, Lucite was an extremely popular material for jewelry, with several companies specialized in creating high-quality pieces from this material. Lucite beads and ornaments are still sold by jewelry suppliers.

* Acrylic sheets are produced in dozens of standard colors, most commonly sold using color numbers developed by Rohm & Haas in the 1950s.

{{See also|Acrylic embedment}}

[[File:Bromine vial in acrylic cube.jpg|thumb|Illustrative and secure [[bromine]] chemical sample used for teaching. The glass sample vial of the corrosive and poisonous liquid has been cast into an acrylic plastic cube]]

[[Methyl methacrylate]] "[[synthetic resin]]" for casting (simply the bulk liquid chemical) may be used in conjunction with a polymerization catalyst such as [[methyl ethyl ketone peroxide]] (MEKP), to produce hardened transparent PMMA in any shape, from a mold. Objects like insects or coins, or even dangerous chemicals in breakable quartz ampules, may be embedded in such "cast" blocks, for display and safe handling.

=== Other uses ===

[[File:Acrylic Heels.jpg|thumb|upright|[[High-heeled footwear|High-heel shoes]] made of Lucite]]

[[File:Basscat Bass.jpg|thumb|left|An electric [[bass guitar]] made from poly(methyl methacrylate)]]

[[File:Futuro house Warrington.JPG|thumb|upright|A [[Futuro]] house in [[Warrington, New Zealand]]]]

* PMMA, in the commercial form Technovit 7200 is used vastly in the medical field. It is used for plastic histology, electron microscopy, as well as many more uses.

* PMMA has been used to create ultra-white opaque membranes that are flexible and switch appearance to transparent when wet.<ref>{{cite journal |last1=Syurik |first1=Julia |last2=Jacucci |first2=Gianni |last3=Onelli |first3=Olimpia D. |last4=Holscher |first4=Hendrik |last5=Vignolini |first5=Silvia |date=22 February 2018 |title=Bio-inspired Highly Scattering Networks via Polymer Phase Separation |journal=Advanced Functional Materials |volume=28 |issue=24 |page=1706901 |doi=10.1002/adfm.201706901 |doi-access=free}}</ref>

* Acrylic is used in tanning beds as the transparent surface that separates the occupant from the tanning bulbs while tanning. The type of acrylic used in tanning beds is most often formulated from a special type of polymethyl methacrylate, a compound that allows the passage of ultraviolet rays.

* Sheets of PMMA are commonly used in the sign industry to make flat cut out letters in thicknesses typically varying from {{convert|3|to|25|mm|in|1|sp=us}}. These letters may be used alone to represent a company's name and/or logo, or they may be a component of illuminated channel letters. Acrylic is also used extensively throughout the sign industry as a component of wall signs where it may be a backplate, painted on the surface or the backside, a faceplate with additional raised lettering or even photographic images printed directly to it, or a spacer to separate sign components.

* PMMA was used in [[Laserdisc]] optical media.<ref>{{cite book |url=https://archive.org/details/howelectronicthi00good_0 |url-access=registration |quote=PMMA Laserdisc. |title=How Electronic Things Work... And What to do When They Don't |last=Goodman |first=Robert L. |date=2002-11-19 |publisher=McGraw Hill Professional |isbn=9780071429245 |language=en}}</ref> ([[CD]]s and [[DVD]]s use both acrylic and polycarbonate for impact resistance).

* It is used as a light guide for the backlights in [[TFT LCD|TFT-LCDs]].<ref>{{Citation |last1=Williams |first1=K.S. |title=Recycling liquid crystal displays |date=2012 |url=https://linkinghub.elsevier.com/retrieve/pii/B9780857090898500143 |work=Waste Electrical and Electronic Equipment (WEEE) Handbook |pages=312–338 |publisher=Elsevier |language=en |doi=10.1533/9780857096333.3.312 |isbn=978-0-85709-089-8 |access-date=2022-06-27 |last2=Mcdonnell |first2=T.}}</ref>

* [[Plastic optical fiber]] used for short-distance communication is made from PMMA, and perfluorinated PMMA, clad with fluorinated PMMA, in situations where its flexibility and cheaper installation costs outweigh its poor heat tolerance and higher attenuation versus glass fiber.

* PMMA, in a purified form, is used as the matrix in [[laser dye]]-doped organic solid-state gain media for tunable [[solid state dye lasers]].<ref>[[F. J. Duarte|Duarte, F. J.]] (Ed.), ''Tunable Laser Applications'' (CRC, New York, 2009) Chapters 3 and 4.</ref>

* In [[semiconductor]] research and industry, PMMA aids as a [[resist (semiconductor fabrication)|resist]] in the [[electron beam lithography]] process. A solution consisting of the polymer in a solvent is used to [[spin coating|spin coat]] [[silicon]] and other semiconducting and semi-insulating wafers with a thin film. Patterns on this can be made by an electron beam (using an [[electron microscope]]), deep UV light (shorter wavelength than the standard [[photolithography]] process), or [[X-ray]]s. Exposure to these creates chain scission or (de-[[cross-link]]ing) within the PMMA, allowing for the selective removal of exposed areas by a chemical developer, making it a positive photoresist. PMMA's advantage is that it allows for extremely high resolution patterns to be made. Smooth PMMA surface can be easily nanostructured by treatment in oxygen [[radio-frequency plasma]]<ref name="vacuum2010">{{cite journal |doi=10.1134/S1027451010010015 |title=Vacuum ultraviolet smoothing of nanometer-scale asperities of poly(methyl methacrylate) surface |year=2010 |last1=Lapshin |first1=R. V. |last2=Alekhin |first2=A. P. |last3=Kirilenko |first3=A. G. |last4=Odintsov |first4=S. L. |last5=Krotkov |first5=V. A. |journal=Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques |volume=4 |issue=1 |pages=1–11 |s2cid=97385151}}</ref> and nanostructured PMMA surface can be easily smoothed by [[vacuum ultraviolet]] (VUV) irradiation.<ref name="vacuum2010"/>

* PMMA is used as a shield to stop beta radiation emitted from radioisotopes.

* Small strips of PMMA are used as [[dosimeter]] devices during the [[gamma ray|Gamma]] Irradiation process. The optical properties of PMMA change as the gamma dose increases, and can be measured with a [[spectrophotometry|spectrophotometer]].

* [[black light|Blacklight]]-reactive [[UV tattoo|UV tattoos]] may use [[tattoo ink]] made with PMMA [[micro-encapsulation|microcapsule]]s and [[Fluorescence|fluorescent]] dyes.<ref>{{Cite journal |last=Bedocs |first=Paul M. |last2=Cliffel |first2=Maureen |last3=Mahon |first3=Michael J. |last4=Pui |first4=John |date=March 2008 |title=Invisible tattoo granuloma |url=https://pubmed.ncbi.nlm.nih.gov/18441850/ |journal=Cutis |volume=81 |issue=3 |pages=262–264 |issn=0011-4162 |pmid=18441850}}</ref>

* In the 1960s, [[luthier]] [[Dan Armstrong]] developed a line of electric guitars and basses whose bodies were made completely of acrylic. These instruments were marketed under the [[Ampeg]] brand. [[Ibanez]]<ref>[http://www.ibanezregister.com/Gallery/js/gal-js2k.htm JS2K-PLT] {{webarchive|url=https://web.archive.org/web/20070928120415/http://www.ibanezregister.com/Gallery/js/gal-js2k.htm |date=2007-09-28}}. Ibanezregister.com. Retrieved 2012-05-09.</ref> and [[B.C. Rich]] have also made acrylic guitars.

* [[Ludwig-Musser]] makes a line of acrylic drums called Vistalites, well known as being used by [[Led Zeppelin]] drummer [[John Bonham]].

* [[Artificial nails]] in the "acrylic" type often include PMMA powder.<ref>{{cite book |title=Australian nail technology |last=Symington |first=Jan |publisher=Tertiary Press |year=2006 |isbn=978-0864585981 |location=Croydon, Victoria, Australia |page=11 |chapter=Salon management}}</ref>

* Some modern briar, and occasionally meerschaum, tobacco pipes sport stems made of Lucite.

* PMMA technology is utilized in roofing and waterproofing applications. By incorporating a polyester fleece sandwiched between two layers of catalyst-activated PMMA resin, a fully reinforced liquid membrane is created ''in situ''.

* PMMA is a widely used material to create [[deal toy]]s and [[tombstone (financial industry)|financial tombstones]].

* PMMA is used by the Sailor Pen Company of [[Kure, Hiroshima|Kure, Japan]], in their standard models of gold-[[nib (pen)|nib]] [[Fountain Pen|fountain pens]], specifically as the cap and body material.

== See also ==

* [[Cast acrylic]]

* [[Organic laser]]

* [[Organic photonics]]

* [[Polycarbonate]]

== References ==

{{refs}}

== External links ==

* [https://www.theplasticshop.co.uk/plastic_technical_data_sheets/perspex_technical_properties_data_sheet.pdf Perspex Technical Properties]

* [https://www.theplasticshop.co.uk/plastic_safety_data_sheets/perspex_safety_data_sheet.pdf Perspex Material Safety Data Sheet (MSDS)]

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