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Encyclopedia > Polymethyl methacrylate
Polymethyl methacrylate
Polymethyl methacrylate

Polymethyl methacrylate Image File history File links Download high resolution version (1004x1271, 16 KB) Summary Description: Skeletal formula of the polymethyl methacrylate repeating unit (Perspex, (C5O2H8)n). ... Image File history File links Download high resolution version (2877x909, 51 KB) Summary Description: Skeletal formula of a short length of a polymethyl methacrylate chain (Perspex, (C5O2H8)n). ...

Chemical name poly(methyl 2-methylpropenoate)
Chemical formula (C5O2H8)n
Synonyms polymethylmethacrylate
PMMA
poly(methyl methacrylate)
methyl methacrylate resin
Molecular mass varies
CAS number 9011-14-7
Density 1.19 g/cm3
Melting point 130-140°C (265-285°F)
Boiling point xx.x °C
Refractive index 1.492 (λ=589.3 nm)
V-number 55.3
SMILES C[C](C)C(=O)OC
Disclaimer and references
Structure of methyl methacrylate, the monomer that makes up PMMA
Enlarge
Structure of methyl methacrylate, the monomer that makes up PMMA

Polymethyl methacrylate (PMMA) or poly(methyl 2-methylpropenoate) is the synthetic polymer of methyl methacrylate. This thermoplastic and transparent plastic is sold by the tradenames Plexiglas, Perspex, Acrylite, Acrylplast, and Lucite and is commonly called acrylic glass or simply acrylic. The material was developed in 1928 in various laboratories and was brought to market in 1933 by the German Company Rohm and Haas (GmbH & Co. KG). IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. ... A chemical formula (also called molecular formula) is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... ‹ The template below has been proposed for deletion. ... The molecular mass (abbreviated MM) of a substance, called molecular weight and abbreviated as MW, is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of carbon-12). ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... The melting point of a solid is the temperature at which it changes state from solid to liquid. ... The boiling point of a substance is the temperature at which it can change its state from a liquid to a gas throughout the bulk of the liquid at a given pressure. ... The refractive index of a material is the factor by which the phase velocity of electromagnetic radiation is slowed relative to vacuum. ... An Abbe diagram plots the Abbe number against refractive index for a range of different glasses (red dots). ... The simplified molecular input line entry specification or SMILES is a specification for unambiguously describing the structure of chemical molecules using short ASCII strings. ... Image File history File links Download high resolution version (1215x976, 14 KB) Summary Description: Skeletal formula of methyl methacrylate (methyl 2-methylprop-2-enoate, C5H8O2). ... Image File history File links Download high resolution version (1215x976, 14 KB) Summary Description: Skeletal formula of methyl methacrylate (methyl 2-methylprop-2-enoate, C5H8O2). ... Methyl methacrylate is a chemical compound mostly known as monomer for the production of the transparent plastic polymethyl methacrylate (PMMA). ... Synthetic polymers are often referred to as plastics, such as the well-known polyethylene and nylon. ... Methyl methacrylate is a chemical compound mostly known as monomer for the production of the transparent plastic polymethyl methacrylate (PMMA). ... A thermoplastic is a material that is plastic or deformable, melts to a liquid when heated and freezes to a brittle, glassy state when cooled sufficiently. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Plastic covers a range of synthetic or semisynthetic polymerization products. ... 1928 (MCMXXVIII) was a leap year starting on Sunday (link will take you to calendar). ... 1933 (MCMXXXIII) was a common year starting on Sunday (link will take you to calendar). ... Rohm and Haas is a special materials manufacturing company based in Philadelphia, Pennsylvania. ...


Properties

The material is often used as an alternative to glass. Differences in the properties of the two materials include: This article refers to the material. ...

  • PMMA is lighter: its density (1190 kg/m3) is about half that of glass.
  • PMMA does not shatter.
  • PMMA is softer and more easily scratched than glass. This can be overcome with scratch-resistant coatings.
  • PMMA can be easily formed, by heating it to 100 degrees Celsius.
  • PMMA transmits more light (92% of visible light) than glass.
  • Unlike glass, PMMA does not filter UV (ultraviolet) light. PMMA transmits UV light, at best intensity, down to 300 nm. Some manufacturers coat their PMMA with UV films to add this property.
  • PMMA allows infrared light of up to 2800 nm wavelength to pass. 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).

PMMA can be joined using cyanoacrylate cement (so-called "Superglue"), or by using liquid di- or trichloromethane to dissolve the plastic at the joint which then fuses and sets, forming an almost invisible weld. PMMA can also be easily polished to restore cut edges to full transparency. Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... A degree Celsius (°C) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701-1744), who first proposed a similar system in 1742. ... Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength shorter than that of the visible region, but longer than that of soft X-rays. ... A nanometre (American spelling: nanometer, symbol: nm) is 1. ... Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than that of visible light, but shorter than that of microwave radiation. ... A nanometre (American spelling: nanometer, symbol: nm) is 1. ... Cyanoacrylate monomer Cyanoacrylate is the generic name for substances such as methyl-2-cyanoacrylate, which is typically sold under trademarks like Superglue and Krazy Glue, and 2-octyl cyanoacrylate, which is used in medical glues such as Dermabond and Traumaseal. ... Dichloromethane or Methylene chloride is a chemical compound widely used as a solvent for organic materials. ... PEL-TWA (OSHA) 50 ppm (240 mg/m3) IDLH (NIOSH) 500 ppm Flash point non-flammable RTECS number FS9100000 Supplementary data page Structure & properties n, εr, etc. ...


To produce 1 kg of PMMA, about 2 kg of petroleum is needed. In the presence of air, PMMA ignites at 460° C and burns completely to form only carbon dioxide and water. Pumpjack pumping an oil well near Sarnia, Ontario Petroleum (from Greek petra – rock and elaion – oil or Latin oleum – oil ), crude oil, sometimes colloquially called black gold or Texas Tea, is a thick, dark brown or greenish liquid. ... A degree Celsius (°C) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701-1744), who first proposed a similar system in 1742. ... Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. ... A girl in a swimming pool Water (from the Old English waeter; c. ...


If in the structure of PMMA the methyl groups (CH3) attached to the C atoms are replaced by single hydrogen atoms, we obtain poly(methyl acrylate), a white soft rubbery material. It is softer than PMMA because its long polymer chains are thinner and smoother and can more easily slide past each other. In chemistry a methyl-group is a hydrophobic Alkyl functional group which is derived from methane (CH4). ...


Uses

Underwater restaurant Ithaa, five meters below sealevel, is encased in PMMA
Underwater restaurant Ithaa, five meters below sealevel, is encased in PMMA

PMMA is used for instance in the lenses of automobile running-lights. The spectator protection in ice hockey stadiums is made of PMMA, as are the largest windows and aquariums in the world. The material is used to produce laserdiscs, and sometimes also for DVDs, but the more expensive polycarbonate (also used for CDs) has better properties when exposed to moisture. Image File history File links Ithaa1. ... Image File history File links Ithaa1. ... Inside view of Ithaa Ithaa, which means pearl in Dhivehi, is the worlds first-ever undersea restaurant, secured five meters below sea level, at Rangali Island of Hilton Maldives Resort & Spa. ... Ice hockey, known simply as hockey in areas where it is more common than field hockey, is a team sport played on ice. ... For other uses, see Aquarium (disambiguation). ... Pioneers LaserDisc Logo Laserdisc certification mark The laserdisc (LD) was the first commercial optical disc storage medium, and was used primarily for the presentation of movies. ... DVD-R writing/reading side DVD (also known as Digital Versatile Disc or Digital Video Disc) is an optical disc storage media format that can be used for data storage, including movies with high video and sound quality. ... Polycarbonates are a particular group of thermoplastics. ... CD may stand for: Compact Disc Canadian Forces Decoration Cash Dispenser (at least used in Japan) CD LPMud Driver Centrum-Demokraterne (Centre Democrats of Denmark) Certificate of Deposit České Dráhy (Czech Railways) Chad (NATO country code) Chalmers Datorförening (computer club of the Chalmers University of Technology) a 1960s...


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. Git Up!, Acrylic painting of Muhammad Ali vs. ... A girl in a swimming pool Water (from the Old English waeter; c. ... In chemistry, hydrophobic or lipophilic species, or hydrophobes, tend to be electrically neutral and nonpolar, and thus prefer other neutral and nonpolar solvents or molecular environments. ...


PMMA has a good degree of compatibilty 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. Hard contact lenses are frequently made of this material; soft contact lenses are often made of a related polymer, in which acrylate monomers are used that contain one or more hydroxyl groups to make them hydrophilic. To meet Wikipedias quality standards, this article or section may require cleanup. ... This article or section does not cite its references or sources. ... Human eye cross-sectional view. ... A contact lens (also known simply as a contact) is a corrective, cosmetic, or therapeutic lens usually placed on the cornea of the eye. ... Hydroxide is a functional group consisting of oxygen and hydrogen: -O−H It has a charge of 1-. The term hydroxyl group is used when the functional group -OH is counted as a substituent of an organic compound. ... The adjective hydrophilic describes something that likes water (from Greek hydros = water; philos = friend). ...


In orthopedics, PMMA bone cement is used to affix implants and to remodel lost bone. It is supplied as a powder with liquid methyl methacrylate (MMA); when mixed together these yield a dough-like cement that gradually hardens in the body. Surgeons can judge the curing of the PMMA bone cement by the smell of MMA in the patient's breath. Athough PMMA is biologically compatible, MMA is considered to be an irritant and a possible carcinogen. Dentures are often made of PMMA. In cosmetic surgery, tiny PMMA microspheres suspended in some biological fluid are injected under the skin to reduce wrinkles or scars permanently. Orthopedic surgery or orthopedics (BE: orthopaedics) is the branch of surgery concerned with acute, chronic, traumatic and recurrent injuries and other disorders of the locomotor system, its musclular and bone parts. ... Methyl methacrylate is a chemical compound mostly known as monomer for the production of the transparent plastic polymethyl methacrylate (PMMA). ... Categories: Stub | Dentistry ... Plastic surgery is a general term for operative manual and instrumental treatment which is performed for functional or aesthetic reasons. ...


Recently, a blacklight-reactive tattoo ink using PMMA microcapsules has surfaced. The technical name is BIOMETRIX System-1000, and it is marketed under the name "Chameleon Tattoo Ink". This ink is reportedly quite safe for use, and claims to be FDA approved for use on wildlife that may enter the food supply. Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... A tattoo is a design or marking made by the insertion of a pigment into punctures or cuts in the skin. ... An ink is a liquid containing various pigments and/or dyes used for colouring a surface to render an image or text. ... Micro-encapsulation is a process in which tiny particles or droplets are surrounded by a coating to give small capsules with many useful properties. ... The United States Food and Drug Administration is the government agency responsible for regulating food, dietary supplements, drugs, cosmetics, medical devices, biologics and blood products in the United States. ...


See also


  Results from FactBites:
 
Advice And Tips About RGP Contact Lenses (386 words)
The beauty behind these contact lenses is that is that people suffering from moderately impaired vision or a severe astigmatism now have the opportunity to improve their vision through the use of contacts for the very first time.
As a result of this unhealthy condition research was conducted in order to produce a soft contact lens and shortly thereafter the RGP contact lenses, which became available for mass purchase during the 1980s.
Rigid gas permeable lenses are constructed from a silicone base allowing them to be slightly more flexible and able to easily pass oxygen to the eyes unlike their forefathers, the polymethyl methacrylate hard contact lenses.
Process for producing a casting plate of polymethyl methacrylate - Patent 4214064 (2172 words)
In 100 parts of the methyl methacrylate syrup as used in Example 1 were dissolved azobisisobutyronitrile as an initiator, dilauryl thiodipropionate as a stabilizer and sodium dioctylsulfosuccinate as a surfactant in amounts as indicated in Table 2, and the resulting mixture was deaerated.
A continuous casting plate of polymethyl methacrylate was obtained in the same manner as in Example 1 except using 0.1 part of distearyl thiodipripionate as the stabilizer and 0.01 part of polyethyleneglycol dodecylphenyl ether as the surfactant.
A continuous casting plate of polymethyl methacrylate was obtained by using the resulting syrup as in Example 1, except that 0.05 part of phosphoric acid ester of laurylpolyethyleneglycol was used as the surfactant.
  More results at FactBites »

 
 

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