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Poly(methyl methacrylate)
IUPAC name
Poly(methyl 2-methylpropenoate)
Other names
  • Poly(methyl methacrylate)
  • PMMA
  • Methyl methacrylate resin
  • Perspex
3D model (JSmol)
  • None
ECHA InfoCard 100.112.313 Edit this at Wikidata
  • CCC(C)(C(=O)OC)CC(C)(C(=O)OC)CC(C)(C(=O)OC)CC(C)(C(=O)OC)CC(C)(C(=O)OC)C
Molar mass Varies
Density 1.18 g/cm3[1]
−9.06×10−6 (SI, 22 °C)[2]
1.4905 at 589.3 nm[3]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Lichtenberg figure: high-voltage dielectric breakdown in an acrylic polymer block

Poly(methyl methacrylate) (PMMA) is the synthetic polymer derived from methyl methacrylate. It is used as an engineering plastic, and it is a 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 (see below). This plastic is often used in sheet form as a lightweight or shatter-resistant alternative to 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.


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[4] 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 Company under the trademark Plexiglas.[5]

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] 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.[6] 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.[7] Civilian applications followed after the war.[8]


Common orthographic stylings include polymethyl methacrylate[9][10] and polymethylmethacrylate. The full IUPAC chemical name is poly(methyl 2-methylpropenoate). (It is a common mistake to use "an" instead of "en".)

Although PMMA is often called simply "acrylic", acrylic can also refer to other polymers or copolymers containing polyacrylonitrile. Notable trade names and brands include Acrylite,[11] Altuglas,[12] Astariglas,[13] Cho Chen,[14] Crystallite, Cyrolite,[15] Hesalite (when used in Omega watches), Lucite,[16] Optix,[15] Oroglas,[17] PerClax, Perspex,[15] Plexiglas,[15][18] R-Cast,[19] and Sumipex.

PMMA is an economical alternative to polycarbonate (PC) when tensile strength, flexural strength, transparency, polishability, and UV tolerance are more important than impact strength, chemical resistance, and heat resistance.[20] Additionally, PMMA does not contain the potentially harmful bisphenol-A subunits found in polycarbonate and is a far better choice for laser cutting.[21] 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 force, and is more prone to scratching than conventional inorganic glass, but modified PMMA is sometimes able to achieve high scratch and impact resistance.


Skeletal structure of methyl methacrylate, the constituent monomer of PMMA
Pieces of Plexiglas®, 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 g/cm3,[1][22] which is less than half that of glass.[1] It also has good impact strength, higher than both glass and polystyrene, but significantly lower than polycarbonate and some engineered polymers. PMMA ignites at 460 °C (860 °F) and burns, forming carbon dioxide, water, carbon monoxide, and low-molecular-weight compounds, including formaldehyde.[23]

PMMA transmits up to 92% of visible light (3 mm thickness), and gives a reflection of about 4% from each of its surfaces due to its refractive index (1.4905 at 589.3 nm).[3] It filters ultraviolet (UV) light at wavelengths below about 300 nm (similar to ordinary window glass). Some manufacturers[24] add coatings or additives to PMMA to improve absorption in the 300–400 nm range. PMMA passes infrared light of up to 2,800 nm and blocks IR of longer wavelengths up to 25,000 nm. Colored PMMA varieties allow specific IR wavelengths to pass while blocking visible light (for remote control or heat sensor applications, for example).

PMMA swells and dissolves in many organic solvents; it also has poor resistance to many other chemicals due to its easily 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.[25]

PMMA has a maximum water absorption ratio of 0.3–0.4% by weight.[22] Tensile strength decreases with increased water absorption.[26] Its coefficient of thermal expansion is relatively high at (5–10)×10−5 °C−1.[27]

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.[28][29]

PMMA can be joined using cyanoacrylate cement (commonly known as superglue), with heat (welding), or by using chlorinated solvents such as dichloromethane or trichloromethane[30] (chloroform) to dissolve the plastic at the joint, which then fuses and sets, forming an almost invisible 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.[31] 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, it will not shatter. Rather, it breaks into large dull pieces. Since PMMA is softer and more easily scratched than glass, 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 comonomers, additives, and fillers are created for uses where specific properties are required. For example,

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.[33]

The glass transition temperature (Tg) of atactic PMMA is 105 °C (221 °F). The Tg values of commercial grades of PMMA range from 85 to 165 °C (185 to 329 °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 Tg. The forming temperature starts at the glass transition temperature and goes up from there.[34] 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.


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Close-up of pressure sphere of the 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 & 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.[33]

Glass substitute

10-meter (33-foot) deep Monterey Bay Aquarium tank has acrylic windows up to 33 centimeters (13 inches) thick to withstand the water pressure.

Daylight redirection

Main article: Anidolic lighting


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


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.[49]

Art and aesthetics

Lexus Perspex car sculpture
PMMA art by Manfred Kielnhofer
Kawai acrylic grand piano
Lucite Bangle Bracelet

See also: Acrylic embedment

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

High-heel shoes made of Lucite
An electric bass guitar made from poly(methyl methacrylate)
A Futuro house in Warrington, New Zealand

See also


  1. ^ a b c Polymethylmethacrylate (PMMA, Acrylic) Archived 2015-04-02 at the Wayback Machine. Retrieved 2015-03-23.
  2. ^ Wapler, M. C.; Leupold, J.; Dragonu, I.; von Elverfeldt, D.; Zaitsev, M.; Wallrabe, U. (2014). "Magnetic properties of materials for MR engineering, micro-MR and beyond". JMR. 242 (2014): 233–242. arXiv:1403.4760. Bibcode:2014JMagR.242..233W. doi:10.1016/j.jmr.2014.02.005. PMID 24705364. S2CID 11545416.
  3. ^ a b Refractive index and related constants – Poly(methyl methacrylate) (PMMA, Acrylic glass) Archived 2014-11-06 at the Wayback Machine. Retrieved 2014-10-27.
  4. ^ "PMMA Material | Beluns® Plastic". Retrieved 2023-07-05.
  5. ^ Plexiglas history by Evonik (in German).
  6. ^ "DPMAregister | Marken - Registerauskunft". Retrieved 2021-09-29.
  7. ^ Congressional Record: Proceedings and Debates of the 77th Congress First Session (Volume 87, Part 11 ed.). Washington, D.C.: U.S. Government Printing Office. 1941. pp. A2300–A2302. Retrieved 3 August 2020.
  8. ^ "Polymethyl methacrylate | chemical compound". Archived from the original on 2017-10-31. Retrieved 2017-05-22.
  9. ^ "polymethyl methacrylate", Dorland's Illustrated Medical Dictionary, Elsevier
  10. ^ "polymethyl methacrylate". Dictionary.
  11. ^ "Acrylite Online Shop | Cut-to-Size | Sheets | Rods | Tubes". Archived from the original on 2013-10-07. Retrieved 2018-11-15.
  12. ^ David K. Platt (1 January 2003). Engineering and High Performance Plastics Market Report: A Rapra Market Report. Smithers Rapra. p. 170. ISBN 978-1-85957-380-8. Archived from the original on 21 April 2016.
  13. ^ "Cast Acrylic Sheet Manufacturer in Indonesia". Astari Global. 2016-08-22. Retrieved 2022-03-03.
  14. ^ "Cho Chen Ind. Co., Ltd". Retrieved 2020-04-17.
  15. ^ a b c d Charles A. Harper; Edward M. Petrie (10 October 2003). Plastics Materials and Processes: A Concise Encyclopedia. John Wiley & Sons. p. 9. ISBN 978-0-471-45920-0. Archived from the original on 20 April 2016.
  16. ^ "Trademark Electronic Search System". TESS. US Patent and Trademark Office. p. Search for Registration Number 0350093. Retrieved 29 June 2014.
  17. ^ "Misused materials stoked Sumerland fire". New Scientist. 62 (902). IPC Magazines: 684. 13 June 1974. ISSN 0262-4079. Archived from the original on 21 April 2016.
  18. ^ "WIPO Global Brand Database". Archived from the original on 2013-01-21. Retrieved 2013-01-25.
  19. ^ "R-Cast® a Brief History". Reynolds Polymer Technology. Archived from the original on 2015-09-24.
  20. ^ Hydrosight. "Acrylic vs. Polycarbonate: A quantitative and qualitative comparison". Archived from the original on 2017-01-19.
  21. ^ "Never cut these materials" (PDF).[failed verification]
  22. ^ a b DATA TABLE FOR: Polymers: Commodity Polymers: PMMA Archived 2007-12-13 at the Wayback Machine. Retrieved 2012-05-09.
  23. ^ Zeng, W. R.; Li, S. F.; Chow, W. K. (2002). "Preliminary Studies on Burning Behavior of Polymethylmethacrylate (PMMA)". Journal of Fire Sciences. 20 (4): 297–317. doi:10.1177/073490402762574749. hdl:10397/31946. S2CID 97589855. INIST 14365060.
  24. ^ Altuglas International Plexiglas UF-3 UF-4 and UF-5 sheets Archived 2006-11-17 at the Wayback Machine. Retrieved 2012-05-09.
  25. ^ Myer Ezrin Plastics Failure Guide: Cause and Prevention Archived 2016-04-21 at the Wayback Machine, Hanser Verlag, 1996 ISBN 1-56990-184-8, p. 168
  26. ^ Ishiyama, Chiemi; Yamamoto, Yoshito; Higo, Yakichi (2005). Buchheit, T.; Minor, A.; Spolenak, R.; et al. (eds.). "Effects of Humidity History on the Tensile Deformation Behaviour of Poly(methyl–methacrylate) (PMMA) Films". MRS Proceedings. 875: O12.7. doi:10.1557/PROC-875-O12.7.
  27. ^ "Tangram Technology Ltd. – Polymer Data File – PMMA". Archived from the original on 2010-04-21.
  28. ^ Cappitelli, Francesca; Principi, Pamela; Sorlini, Claudia (2006). "Biodeterioration of modern materials in contemporary collections: Can biotechnology help?". Trends in Biotechnology. 24 (8): 350–4. doi:10.1016/j.tibtech.2006.06.001. PMID 16782219.
  29. ^ Rinaldi, Andrea (2006). "Saving a fragile legacy. Biotechnology and microbiology are increasingly used to preserve and restore the world's cultural heritage". EMBO Reports. 7 (11): 1075–9. doi:10.1038/sj.embor.7400844. PMC 1679785. PMID 17077862.
  30. ^ "Working with Plexiglas" Archived 2015-02-21 at the Wayback Machine.
  31. ^ Andersen, Hans J. "Tensions in acrylics when laser cutting". Archived from the original on 8 December 2015. Retrieved 23 December 2014.
  32. ^ López, Alejandro; Hoess, Andreas; Thersleff, Thomas; Ott, Marjam; Engqvist, Håkan; Persson, Cecilia (2011-01-01). "Low-modulus PMMA bone cement modified with castor oil". Bio-Medical Materials and Engineering. 21 (5–6): 323–332. doi:10.3233/BME-2012-0679. ISSN 0959-2989. PMID 22561251.
  33. ^ a b Stickler, Manfred; Rhein, Thoma (2000). "Polymethacrylates". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a21_473. ISBN 3527306730.
  34. ^ Ashby, Michael F. (2005). Materials Selection in Mechanical Design (3rd ed.). Elsevier. p. 519. ISBN 978-0-7506-6168-3.
  35. ^ Kutz, Myer (2002). Handbook of Materials Selection. John Wiley & Sons. p. 341. ISBN 978-0-471-35924-1.
  36. ^ Terry Pepper, Seeing the Light, Illumination Archived 2009-01-23 at the Wayback Machine. Retrieved 2012-05-09.
  37. ^ Deplazes, Andrea, ed. (2013). Constructing Architecture – Materials Processes Structures, A Handbook. Birkhäuser. ISBN 978-3038214526.
  38. ^ Yeang, Ken. Light Pipes: An Innovative Design Device for Bringing Natural Daylight and Illumination into Buildings with Deep Floor Plan Archived 2009-03-05 at the Wayback Machine, Nomination for the Far East Economic Review Asian Innovation Awards 2003
  39. ^ "Lighting up your workplace". Fresh Innovators. May 9, 2005. Archived from the original on 2 July 2005.
  40. ^ Kenneth Yeang Archived 2008-09-25 at the Wayback Machine, World Cities Summit 2008, June 23–25, 2008, Singapore
  41. ^ Gerchikov, Victor; Mossman, Michele; Whitehead, Lorne (2005). "Modeling Attenuation versus Length in Practical Light Guides". LEUKOS. 1 (4): 47–59. doi:10.1582/LEUKOS.01.04.003. S2CID 220306943.
  42. ^ How Serraglaze works Archived 2009-03-05 at the Wayback Machine. Retrieved 2012-05-09.
  43. ^ Glaze of light Archived 2009-01-10 at the Wayback Machine, Building Design Online, June 8, 2007
  44. ^ Robert A. Meyers, "Molecular biology and biotechnology: a comprehensive desk reference", Wiley-VCH, 1995, p. 722 ISBN 1-56081-925-1
  45. ^ Apple, David J (2006). Sir Harold Ridely and His Fight for Sight: He Changed the World So That We May Better See It. Thorofare NJ USA: Slack. ISBN 978-1-55642-786-2.
  46. ^ Carroll, Gregory T.; Kirschman, David L. (2022-07-13). "A portable negative pressure unit reduces bone cement fumes in a simulated operating room". Scientific Reports. 12 (1): 11890. Bibcode:2022NatSR..1211890C. doi:10.1038/s41598-022-16227-x. ISSN 2045-2322. PMC 9279392. PMID 35831355.
  47. ^ Kaufmann, Timothy J.; Jensen, Mary E.; Ford, Gabriele; Gill, Lena L.; Marx, William F.; Kallmes, David F. (2002-04-01). "Cardiovascular Effects of Polymethylmethacrylate Use in Percutaneous Vertebroplasty". American Journal of Neuroradiology. 23 (4): 601–4. PMC 7975098. PMID 11950651.
  48. ^ "Filling in Wrinkles Safely". U.S. Food and Drug Administration. February 28, 2015. Archived from the original on 21 November 2015. Retrieved 8 December 2015.
  49. ^ Zarb, George Albert (2013). Prosthodontic treatment for edentulous patients : complete dentures and implant-supported prostheses (13th ed.). St. Louis, Mo.: Elsevier Mosby. ISBN 9780323078443. OCLC 773020864.
  50. ^ de Swart, Ursula. My Life with Jan. Collection of Jock de Swart, Durango, CO
  51. ^ Plexiglas® Color Numbers Archived 2016-05-18 at the Portuguese Web Archive.
  52. ^ Syurik, Julia; Jacucci, Gianni; Onelli, Olimpia D.; Holscher, Hendrik; Vignolini, Silvia (22 February 2018). "Bio-inspired Highly Scattering Networks via Polymer Phase Separation". Advanced Functional Materials. 28 (24): 1706901. doi:10.1002/adfm.201706901.
  53. ^ Goodman, Robert L. (2002-11-19). How Electronic Things Work... And What to do When They Don't. McGraw Hill Professional. ISBN 9780071429245. PMMA Laserdisc.
  54. ^ Williams, K.S.; Mcdonnell, T. (2012), "Recycling liquid crystal displays", Waste Electrical and Electronic Equipment (WEEE) Handbook, Elsevier, pp. 312–338, doi:10.1533/9780857096333.3.312, ISBN 978-0-85709-089-8, retrieved 2022-06-27
  55. ^ Duarte, F. J. (Ed.), Tunable Laser Applications (CRC, New York, 2009) Chapters 3 and 4.
  56. ^ a b Lapshin, R. V.; Alekhin, A. P.; Kirilenko, A. G.; Odintsov, S. L.; Krotkov, V. A. (2010). "Vacuum ultraviolet smoothing of nanometer-scale asperities of poly(methyl methacrylate) surface". Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques. 4 (1): 1–11. doi:10.1134/S1027451010010015. S2CID 97385151.
  57. ^ Bedocs, Paul M.; Cliffel, Maureen; Mahon, Michael J.; Pui, John (March 2008). "Invisible tattoo granuloma". Cutis. 81 (3): 262–264. ISSN 0011-4162. PMID 18441850.
  58. ^ JS2K-PLT Archived 2007-09-28 at the Wayback Machine. Retrieved 2012-05-09.
  59. ^ Symington, Jan (2006). "Salon management". Australian nail technology. Croydon, Victoria, Australia: Tertiary Press. p. 11. ISBN 978-0864585981.