Information AboutPolymethyl Methacrylate |
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, 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). PROPERTIES The material is often used as an alternative to Glass . Differences in the properties of the two materials include:
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. 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 . If in the structure of PMMA the Methyl Group s (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. USES '', 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 Laserdisc s, and sometimes also for DVD s, but the more expensive Polycarbonate (also used for CD s) has better properties when exposed to moisture. 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. PMMA has a good degree of compatibilty with human tissue, and can be used for replacement Intraocular Lens es in the Eye when the original lens has been removed in the treatment of Cataract s. Hard Contact Lens es 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 Group s to make them Hydrophilic . 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. Denture s 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. Modern Furniture , especially in the 1960s and 1970s, makers looking to give their products a Space Age feel also incorporated Lucite and other PMMA products into their designs, especially in office chairs. Recently, a Blacklight -reactive Tattoo Ink using PMMA Microcapsule s 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. SEE ALSO
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