Acrylic glass
Other names	poly(methyl methacrylate) (PMMA) methyl methacrylate resin
Identifiers
CAS number	[9011-14-7]
SMILES	C[C](C)C(=O)OC
Properties
Molecular formula	(C5O2H8)n
Molar mass	varies
Density	1. CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 19 g/cm³
Melting point	130–140 °C (265–285 °F)
Boiling point	200. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid 0 °C (392 °F)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Poly(methyl methacrylate) (PMMA) or poly(methyl 2-methylpropenoate) is a thermoplastic and transparent plastic. In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly A thermoplastic is a Plastic that Melts to a liquid when heated and freezes to a Brittle, very Glassy state when cooled sufficiently In Optics, transparency (also called pellucidity) is the Material property of allowing Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products Chemically, it is the synthetic polymer of methyl methacrylate. Methyl methacrylate is an Organic compound with the formula CH2=C(CH3CO2CH3 It is sold by the tradenames Plexiglas, Limacryl, R-Cast, Perspex, Plazcryl, Acrylex, Acrylite, Acrylplast, Altuglas, Polycast, Oroglass and Lucite and is commonly called acrylic glass or simply acrylic. Acrylic, or acrylic fiber, can also refer to polymers or copolymers containing polyacrylonitrile. Acrylic fibers are Synthetic fibers made from a polymer ( Polyacrylonitrile) with an average molecular weight of ~100000 Polyacrylonitrile ( PAN) is a Resinous fibrous, or Rubbery organic Polymer. The material was developed in 1928 in various laboratories and was brought to market in 1933 by Rohm and Haas Company. Rohm and Haas Company ( a Philadelphia Pennsylvania based company manufactures miscellaneous materials

PMMA is often used as an alternative to glass, and in competition with polycarbonate (PC). Glass in the common sense refers to a Hard, Brittle, transparent Solid, such as that used for Windows many It is often preferred because of its moderate properties, easy handling and processing, and low cost, but behaves in a brittle manner when loaded, especially under an impact force. An impact force is a high Force or shock applied over a short time period To produce 1 kg of PMMA, about 2 kg of petroleum is needed. Petroleum ( L petroleum, from Greek πετρέλαιον, lit In the presence of oxygen, PMMA ignites at 460 °C and burns completely to form only carbon dioxide and water. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the The Celsius Temperature scale was previously known as the centigrade scale. Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Water is a common Chemical substance that is essential for the survival of all known forms of Life.

Contents 1 History 2 Synthesis 3 Processing 4 Properties 4.1 Modification of properties 5 Related polymer poly(methyl acrylate) 6 Uses 6.1 Impact resistant substitute for glass 6.2 Medical technologies and implants 6.3 Artistic and aesthetic uses 6.4 Other uses 7 See also 8 References 9 External Links

History

The first acrylic acid was created in 1843. Year 1843 ( MDCCCXLIII) was a Common year starting on Sunday (link will display the full calendar of the Gregorian Calendar (or a Common Methacrylic acid, derived from acrylic acid, was formulated in 1865. Year 1865 ( MDCCCLXV) was a Common year starting on Sunday (link will display the full calendar of the Gregorian calendar (or a Common year The reaction between methacrylic acid and methyl alcohol results in the ester methyl methacrylate. German chemists Fittig and Paul discovered in 1877 the polymerization process that turns methyl methacrylate into polymethyl methacrylate. Year 1877 ( MDCCCLXXVII) was a Common year starting on Monday (link will display the full calendar of the Gregorian calendar (or a Common In 1936 the first commercially viable production of acrylic safety glass began. Year 1936 ( MCMXXXVI) was a Leap year starting on Wednesday (link will display the full calendar of the Gregorian calendar. During World War II acrylic glass was used for submarine periscopes, and windshields, canopies, and gun turrets for airplanes. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including ^[1]

Synthesis

PMMA is routinely produced by emulsion polymerization, solution polymerization and bulk polymerization. Emulsion polymerization is a type of Radical polymerization that usually starts with an Emulsion incorporating water Monomer, and Surfactant Solution polymerization is a method of industrial Polymerization. Generally radical initiation is used (including living polymerization methods), but anionic polymerization of PMMA can also be performed. In Polymer chemistry, living polymerization is a form of Addition polymerization where the ability of a growing Polymer chain to terminate has

Processing

Thermoplastic PMMA is typically processed at 240–250 °C. All common molding processes may be used, including injection molding, compression molding and extrusion. Injection molding (British moulding Compression molding is a method of Molding in which the molding material generally preheated is first placed in an open heated Mold cavity Extrusion is a process used to create objects of a fixed cross-sectional profile 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. The molecular mass (abbreviated m of a substance, more commonly referred to as molecular weight and abbreviated as MW, is the Mass of one Rubber toughening has been used to increase the strength of PMMA owing to its brittle behavior in response to applied loads. Many Thermoplastics such as Polystyrene and PMMA are brittle when stressed a property which limits applications

PMMA can be joined using cyanoacrylate cement (so-called "Superglue"), with heat (melting), or by using solvents such as di- or trichloromethane to dissolve the plastic at the joint which then fuses and sets, forming an almost invisible weld. Cyanoacrylate is the generic name for cyanoacrylate based fast-acting Glues such as ethyl-2-cyanoacrylate (commonly sold under trade names like Superglue and Krazy Dichloromethane ( DCM) or methylene chloride is the Chemical compound with the formula CH2Cl2 Chloroform, also known as trichloromethane and methyl trichloride, is a Chemical compound with formula C[[Hydrogen H]] Cl Welding is a fabrication process that joins materials usually Metals or Thermoplastics by causing coalescence.

Scratches may easily be removed by polishing.

Laser cutting may be used to form intricate designs from PMMA sheets. Laser cutting is a technology that uses a Laser to cut materials and is typically used for industrial manufacturing applications PMMA vaporises to gaseous compounds (including its monomers) upon laser cutting, so a very clean cut is made, and cutting is performed very easily. In this respect PMMA has an advantage over competing polymers such as polyethylene and polycarbonate, which require higher laser powers and give more messy and charred laser cuts. Polyethylene or polythene ( IUPAC name poly(ethene) is a Thermoplastic commodity heavily used in consumer products (notably the

Properties

• PMMA has a density of 1,150–1,190 kg/m³. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different This is less than half the density of glass, and similar to that of other plastics.
• PMMA has a good impact strength higher than that of glass or polystyrene, but significantly lower than that of polycarbonate or engineering polymers. It does not shatter but instead breaks into large dull pieces.
• PMMA is softer and more easily scratched than glass. Scratch-resistant coatings (which may also have other functions) are often added to PMMA sheets.
• PMMA transmits up to 98% of visible light (per metre)^[2], and gives a ~4% reflection from each of its surfaces on account of its refractive index of 1. In Optics and Spectroscopy, transmittance is the fraction of incident light at a specified Wavelength that passes through a sample The refractive index (or index of Refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves is reduced inside the medium 4893 to 1. 4899.

• PMMA filters ultraviolet (UV) light at wavelengths below ~300 nm. A monomer (from Greek mono "one" and meros "part" is a small Molecule that may become chemically bonded to other Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays A nanometre ( American spelling: nanometer, symbol nm) ( Greek: νάνος nanos dwarf; μετρώ metrό count) is a Some manufacturers^[3] add coatings or additives to PMMA to improve absorption in the 300–400 nm range.
• PMMA allows infrared light of up to 2800 nm wavelength to pass. Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. IR of longer wavelengths, up to 25,000 nm, are essentially blocked. Special formulations of colored PMMA exist to allow specific IR wavelengths to pass while blocking visible light (for remote control or heat sensor applications, for example). A remote control is an electronic device used for the remote operation of a Machine.
• PMMA has excellent environmental stability compared to other plastics such as polycarbonate, and is therefore often the material of choice for outdoors applications.
• PMMA has poor resistance to solvents, as it swells and dissolves easily. It also has poor resistance to many other chemicals on account of its easily hydrolyzed ester groups. Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least

Modification of properties

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,

• 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.
• Plasticizers may be added to improve processing properties, lower the glass transition temperature, or improve impact properties.
• Dyes may be added to give color for decorative applications, or to protect against (or filter) UV light.
• Fillers may be added to improve cost-effectivness.

Related polymer poly(methyl acrylate)

The polymer of methyl acrylate, PMA or poly(methyl acrylate), is similar to poly(methyl methacrylate), except for the lack of methyl groups on the backbone carbon chain. ^[4] PMA is a soft white rubbery material that is softer than PMMA because its long polymer chains are thinner and smoother and can more easily slide past each other.

Uses

PMMA or Acrylic is a versatile material and has been used in a wide range of fields and applications.

Impact resistant substitute for glass

• PMMA Acrylic glass is commonly used for constructing residential and commercial aquariums. An aquarium (plural aquariums or aquaria) is a Vivarium consisting of at least one transparent side in which Water -dwelling Plants
• PMMA is used in the lenses of exterior lights of automobiles. ^[5]
• The spectator protection in ice hockey stadiums is made from PMMA. Ice hockey, often referred to simply as hockey, is a team Sport played on Ice.
• Motorcycle helmet visors
• Police vehicles for riot control often have the regular glass replaced with acrylic to protect the occupants from thrown objects. A motorcycle helmet is a type of protective headgear used by Motorcycle riders Riot control refers to the measures used by police military or other forces to control, disperse and arrest civilians that are involved in a Riot, demonstration
• Acrylic is used for viewing ports and even complete hulls of submersibles, such as the Alicia submarine's viewing spheres and the Bathyscaphe Trieste's windows. Visibility The passenger section of the pressure hull consists of two intersecting transparent acrylic spheres inside diameter and thick Design Trieste was designed by the Swiss scientist Auguste Piccard and built in Italy
• Polycast acrylic sheet is the most widely used material in aircraft transparencies (windows). In applications where the aircraft is pressurized, stretched acrylic is used.

Medical technologies and implants

• PMMA has a good degree of compatibility with human tissue, and can be used for replacement intraocular lenses in the eye when the original lens has been removed in the treatment of cataracts. Tissue is a cellular organizational level intermediate between cells and a complete organism An intraocular lens (IOL is an implanted lens in the Eye, usually replacing the existing crystalline lens because it has been clouded over by a Cataract Eyes are organs that detect Light, and send signals along the Optic nerve to the visual areas of the brain A cataract is a clouding that develops in the crystalline lens of the Eye or in its envelope varying in degree from slight to complete opacity Hard contact lenses are frequently made of this material. A contact lens (also known simply as a contact) is a corrective, cosmetic, or therapeutic lens usually placed on the Cornea Soft contact lenses are often made of a related polymer, where acrylate monomers containing one or more hydroxyl groups make them hydrophilic. Hydroxyl in Chemistry stands for a molecule consisting of an Oxygen atom and a Hydrogen atom connected by a Covalent bond. Hydrophile, from the Greek (hydros "water" and φιλια (philia "friendship" refers to a physical property of a Molecule
• In orthopaedics, PMMA bone cement is used to affix implants and to remodel lost bone. Orthopedic surgery or orthopedics (also spelled orthopaedics) is the branch of Surgery concerned with injuries to or conditions involving the It is supplied as a powder with liquid methyl methacrylate (MMA). When mixed these yield a dough-like cement that gradually hardens. Surgeons can judge the curing of the PMMA bone cement by pressing their thumb on it. Although PMMA is biologically compatible, MMA is considered to be an irritant and a possible carcinogen. The term carcinogen refers to any substance Radionuclide or radiation that is an agent directly involved in the promotion of Cancer or in the fatation of its propagation PMMA has also been linked to cardiopulmonary events in the operating room due to hypotension. In Physiology and Medicine, hypotension refers to an abnormally low Blood pressure. ^[6] Bone cement acts like a grout and not so much like a glue in arthroplasty. Grout is a Construction material used to embed Rebars in Masonry walls connect sections of pre-cast Concrete, fill voids and seal joints (like Arthroplasty (literally "formation of Joint " is an operative procedure of orthopaedic surgery performed in which the arthritic or dysfunctional joint surface Although sticky, it does not bond to either the bone or the implant, it primarily fills the spaces between the prosthesis and the bone preventing motion. A big disadvantage to this bone cement is that it heats to quite a high temperature while setting and because of this it kills the bone in the surrounding area. It has a Young's modulus between cancellous bone and cortical bone. In Solid mechanics, Young's modulus (E is a measure of the Stiffness of an isotropic elastic material Cancellous Bone is a type of Osseous tissue with a low density and strength but very high Surface area, that fills the inner cavity of long bones Cortical bone, or compact bone, is one of two main types of Osseous tissue. Thus it is a load sharing entity in the body not causing bone resorption. Bone resorption is the process by which Osteoclasts break down Bone and release the Minerals resulting in a transfer of calcium from bone fluid to the blood ^[7]
• Dentures are often made of PMMA, and can be colour-matched to the patient's teeth & gum tissue. Dentures are prosthetic devices constructed to replace missing teeth and which are supported by surrounding soft and hard tissues of the Oral cavity. In cosmetic surgery, tiny PMMA microspheres suspended in some biological fluid are injected under the skin to reduce wrinkles or scars permanently. Plastic surgery is a medical specialty interested in the correction of form and function

Artistic and aesthetic uses

• Acrylic paint essentially consists of PMMA suspended in water; however since PMMA is hydrophobic, a substance with both hydrophobic and hydrophilic groups needs to be added to facilitate the suspension. Acrylic paint is fast-drying Paint containing pigment suspended in an acrylic polymer Emulsion. In Chemistry, hydrophobicity (from the combining form of water in Attic Greek hydro- and for fear phobos) refers to the physical property of Hydrophile, from the Greek (hydros "water" and φιλια (philia "friendship" refers to a physical property of a Molecule In Chemistry, A suspension is a Heterogenous fluid containing Solid particles that are sufficiently large for Sedimentation.
• 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. Furniture is the Mass noun for the movable objects which may support the human body (seating furniture and beds, provide storage or hold objects on horizontal The Space Age is a contemporary period encompassing the activities related to the Space Race, Space exploration, space technology and the cultural developments 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. Salvador Domingo Felipe Jacinto Dalí i Domènech 1st Marquis of Púbol (May 11 1904 &ndash January 23 1989 was a Spanish Catalan Surrealist
• Occasionally used as a glass substitute in picture framing, due to its relatively inexpensive cost, light weight, and shatter-resistant nature, as well as the fact that it can be ordered in larger sizes than standard picture-framing glass. A picture frame is a container added to a picture in order to enhance it make it easier to display or in some cases to protect it
• From approximately the 1960s onward, sculptors and glass artists began using acrylics, especially taking advantage of the material's flexibility, light weight, cost and its capacity to refract and filter light.
• Sometimes used to make a Deal toy (in the world of finance or investment banking). A deal toy, or "tombstone" in the Finance and Investment banking world is a highly customizable object which is intended to mark and commemorate the closing The field of finance refers to the concepts of Time, Money and Risk and how they are interrelated Investment banks profit from companies and governments by raising money through issuing and selling Securities in the Capital markets (both equity and

Other uses

• PMMA was used in laserdisc optical media, and has been developed for use in CDs and DVDs. The Laserdisc (LD is an obsolete Home video disc format and was the first commercial Optical disc storage medium A Compact Disc (also known as a CD) is an Optical disc used to store digital data, originally developed for storing digital audio DVD (also known as " Digital Versatile Disc " or " Digital Video Disc " - see Etymology)is ^[8], although the more expensive polycarbonate is usually used because of its higher strength. PMMA-based optical media is also under development for the "TeraDisc" next-generation 3D optical data storage solution by Mempile. 3D optical data storage is the term given to any form of Optical Data storage in which information can be recorded and/or read with three dimensional ^[9]
• Artificial fingernails are made of acrylic.
• In the 1960s, luthier Dan Armstrong developed a line of electric guitars and basses whose bodies were made completely of acrylic. Dan Armstrong was an expert Guitar Luthier and recording session musician These instruments were marketed under the Ampeg brand. Ampeg is a musical instrument amplifier manufacturer headquartered in Woodinville, Washington. Ibanez ^[10] and BC Rich have also made acrylic guitars. Ibanez (ˈaɪbænɛz or /aɪˈbænɛz/ is a Guitar brand owned by Hoshino Gakki and based in Nagoya Aichi, Japan. BC Rich is a manufacturer of Guitars and Bass guitars started by the late Bernardo Chavez Rico in the early 1970s
• Recently a blacklight-reactive tattoo ink using PMMA microcapsules was developed. A Black light or UV Light is a lamp emitting Electromagnetic radiation that is almost exclusively in the soft near ultraviolet range and emits A tattoo is a permanent marking made by inserting ink into the layers of Skin to change the pigment for decorative or other reasons An ink is a Liquid containing various Pigments and/or Dyes used for coloring a surface to produce an Image, text, or Micro-encapsulation is a process in which tiny particles or droplets are surrounded by a coating to give small capsules many useful properties This ink is reportedly safe for use, and claims to be Food and Drug Administration (FDA) approved for use on wildlife that may enter the food supply.
• In semiconductor research and industry, PMMA aids as a resist in the electron beam lithography process. A semiconductor' is a Solid material that has Electrical conductivity in between a conductor and an insulator; it can vary over that Resist is also an album by Kosheen and a song by Rush In Semiconductor fabrication, " resist " refers to both Electron beam lithography (often abbreviated as e-beam lithography) is the practice of scanning a beam of Electrons in a patterned fashion across a surface covered A solution consisting of the polymer in a solvent is used to spin coat silicon and other semiconducting and semi-insulating wafers with a thin film. A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. Spin coating is a procedure used to apply uniform Thin films to flat substrates In short an excess amount of a solution is placed on the substrate which is then rotated Silicon (ˈsɪlɪkən or /ˈsɪlɪkɒn/ silicium is the Chemical element that has the symbol Si and Atomic number 14 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-rays. An electron microscope is a type of Microscope that uses Electrons to illuminate a specimen and create an enlarged image Photolithography (also called optical lithography) is a process used in Microfabrication to selectively remove parts of a thin film (or the bulk of a substrate X-radiation (composed of X-rays) is a form of Electromagnetic radiation. Exposure to these creates chain scission or (de-cross-linking) within the PMMA, allowing for the selective removal of exposed areas by a chemical developer, making it a positive photoresist. Cross-links are bonds that link one Polymer chain to another They can be Covalent bonds or Ionic bonds "Polymer chains" can refer PMMA's advantage is that it allows for extremely high resolution (nanoscale) patterns to be made. It is an invaluable tool in nanotechnology. Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular
• Small strips of PMMA are used as dosimeter devices during the Gamma Irradiation process. A dosimeter is any device used to measure an individual's exposure to a hazardous environment particularly when the hazard is cumulative over long intervals of Time Gamma (uppercase &Gamma, lowercase γ Γάμμα is the third letter of the Greek alphabet. The optical density of PMMA changes as the Gamma dose increases and can be measured with a spectrophotometer. In Physics, spectrophotometry is the quantitative study of electromagnetic spectra.
• It is used as a light guide for the backlights in TFT-LCDs. A thin film transistor liquid crystal display ( TFT-LCD) is a variant of Liquid crystal display (LCD which uses Thin film transistor (TFT technology to
• 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 over glass fiber. Plastic optical fiber (POF (or fibre) is an Optical fiber which is made out of Plastic.
• Sheets of PMMA are commonly used in the sign industry to make flat cut out letters in thicknesses typically varying from 0. 125" to 1". These letters may be used alone to represent a company's name and/or logo, or they may be a component of channel letters which are neon or LED illuminated sign "can" commonly seen worldwide. Acrylic's attractiveness, durability and resistance to warping makes it an ideal interior and exterior sign material.
• Ludwig-Musser makes a line of acrylic drums called Vistalites. Ludwig-Musser is a Drum and Percussion instrument Manufacturer owned by Conn-Selmer Inc They are well known as being used by Led Zeppelin drummer John Bonham. John Henry "Bonzo" Bonham (May 31 1948 – September 25 1980 was an English Drummer and member of the band Led Zeppelin.
• Ear stretching jewelry is also commonly formed out of PMMA, due to its inert nature and shatter-proof qualities. PMMA jewelry is fade-proof, odorless, durable, and easy to polish, giving it that modern stylish sheen.
• Apple Computer's Power Mac G4 Cube was made out of PMMA
• WWE's Elimination Chamber match has 4 "Containment Pods," each with a metal outlining and PMMA walls. Apple Inc, ( formerly Apple Computer Inc, is an American Multinational corporation with a focus on designing and manufacturing Consumer electronics The Power Mac G4 Cube (or as Steve Jobs put it "more affectionately the G4 Cube " was a compact Macintosh Personal computer from World Wrestling Entertainment Inc ( WWE) is a publicly traded privately controlled integrated media (focusing in Television, Internet, The Elimination Chamber is a match type in Professional wrestling (seen in World Wrestling Entertainment)

See also

• Other transparent plastics: polystyrene, polycarbonate

References

External Links

• Acrylic plexi color chart
• 'Vessels' - a sculptural book made from perspex – created by Adele Outteridge and held by the Australian Library of Art, State Library of Queensland

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