Plexiglas/Perspex

In order to ensure perpendicular beam incidence on the cylindrical specimen, the circular B-scan profiles were acquired by high frequency (narrow beam) transducers in a synthetic circular aperture array. From these profiles two-dimensional reflection tomograms were reconstructed using a filtered backprojection technique. Straight line propagation was assumed. Several artificial discontinuity types in a cylindrical Plexiglas (Perspex) specimen were compared with similar artificial discontinuities in a cylindrical A/Si-alloy [2]. Furthermore, examples of real discontinuities (an inclusion and a feed head) in the cylindrical AlSi-alloy are presented. 

Acrylates. Polymethylmethacrylate (Lucite, Plexiglas, Perspex) is easily machined and is widely used with dilute aqueous solutions. Acrylates are resistant to nonoxidizing acids and weak alkalies, but are attacked by concentrated oxidizing acids and strong alkalies. They will withstand petroleum oils and most alcohols, but are generally unsuitable for use in contact with organic solvents. They are dissolved by ketones, esters, and aromatic and chlorinated hydrocarbons. They are thermoplastic and cannot be used continuously above 75 °C. The acrylates are perfectly clear and transparent and often are used to make shields or inert atmosphere enclosures. The materials bum slowly when ignited. 

Poly(methyl methacrylate) Aircraft windows, glazing, fighting Plexiglas, Perspex... 

Methyl ester, methyl methacrylate, polymerizes easily, forming a clear plastic known as Lucia, Plexiglas, Perspex. Sol in methyl ethyl ketone, tetrahydrofuran, esters, aromatic and chlorinated hydrocarbons. LDm orally in rats 8.4... 

Perspex, Plexiglas or lucite) is one of these the two radicals are —CH3 and —COOCH3. Now the difficulties of getting regular arrangements increases, and most of these polymers are amorphous. 

Examples of commercial poly(methyl methacrylate) sheet are Perspex (ICI), Oroglas and Plexiglas (Atoglas). Poly(methyl methacrylate) moulding powders include Diakon (ICI), Acry-ace (Fudow Chemical Co., Japan), Lucite (Du Pont) and Vedril (Montecatini). 

Poly (methyl methacrylate) has excellent optical properties and is marketed under the names Lucite, Plexiglas, and Perspex. 

Acrylite, Altuglas, Altulite, Cyrolite, Diakon, Hesalite, Oroglas, Perspex, Plexiglas, RTP acrylics, Vedril... 

PEP-2 PEP-3 PIPE = mixtures of PETN and Gulf Crown Oil (USA) perchlorate d ammonium 17 perchlorate de barium 29 perchlorate explosives 247 perchlorate de guanidine 157 perchlorate d hydrazine 182 perchlorate de lithium 205 perchlorate de potassium 263 perchlorate de sodium 292 percussion cap percussion primer 95 201 202 247 267 288 289 perforation of oil and gas wells 247 perle d allumage = squib 43, 236 Perlit = picric acid (german) 256 permissibles permitted explosives 14 75 86 88 248 370 peroxides 31 170 252 346 371 peroxide de benzoyle 31 peroxide de tricycloacetone 346 peroxide de zinc = zinc peroxide 371 Perspex = acrylic acid methylester polymer (same as Plexiglas ... 

PMA PMMA = polymer acrylic methylester (Plexiglas Lucite, Perspex) 89... 

The imaging performance of the CW-NMRI system can be demonstrated by showing 2- and 3-D images of a rigid polymer such as poly (methyl methacrylate) (PMMA) (Perspex/Plexiglas). Spectroscopic investigations carried out on this... 

Methyl methacrylate (MMA) is an important commodity since it is polymerized to give poly methylmethacrylate (PMMA), a strong, durable and transparent polymer sold under the trade-names Perspex and Plexiglas. Since the conventional routes to MMA involve either the reaction of acetone with HCN to give the cyanohydrin (which has environmental problems), or the oxidation of isobutene, alternative carbonylation routes to MMA are being developed. One of these is the Lucite Alpha process which is claimed to decrease production costs by ca. 40%. This first synthesizes methyl propionate by a methoxycarbonylation of ethylene (Equation 23), using a palladium catalyst with very high (99.8%) selectivity. In the second step, MMA is formed in 95% selectivity by the reaction of methyl propionate with formaldehyde (Equation 24). 

PALACOS PARAGLAS PARAPLEX P 543 PERSPEX PLEXIGLAS PLEXIGUM M 920 PMMA... 

Radiation is a major hazard and its stochastic effects should not be underestimated (Ballance et al., 1984). For instance, -particles emitted by have a maximum range of 6 m in air, but less in glass (0.38 cm). Perspex (Plexiglas, 0.64 cm) or water (0.84 cm). The maximum permissible occupational skin dose equivalent in the United States is 30000 mRem/year (7500 mRem/3 months) but six times lower for the lens of the eye. The dose equivalent rate at the surface of a glass container with P (such as Combi-v-vial ) can be close to 500 mRem/hmCi whereas it may be over 170000 mRem/hmCi outside a plastic syringe with a P solution (Zoon, 1987). Without precautions, the maximum permissible dose can thus be received in a matter of minutes or even seconds. In contrast, S does not penetrate the walls of typical containers or the dead layer of skin cells. The main hazard of S is due to inhalation. 

Polymethylacrylate (PMA) and polymethylmethacrylate (PMMA) were discovered, respectively, in 1880 and 1930. The resins have been used for the production of transparent plastic sheets, viz. Plexiglas or Perspex , used for the military aircraft cockpit canopies, gunner s turrets and the like [Riddle, 1954]. Acrylic elastomers (ACM or ANM) were developed by Rohm in 1901, and commercialized in 1948 as Hycar vulcanizable copolymers of ethyl acrylate, allyl maleated lactones, chloroethyl vinyl ether, butadiene, isoprene, acrylonitrile, etc. [Mast et al., 1944]. Since the 1950 s, a wide variety of acrylic compatibilizers and impact modifiers have been developed. 

The other development by ICI laboratories which made a vital wartime contribution was poly (methyl methacrylate), widely known as acrylic, Perspex or Plexiglas. First produced commercially in the UK in 1934, its rigidity, transparency and shatter-resistant properties were soon in high demand for glazing, aircraft canopies and protective screens because acrylics provided a lower density, weather-resistant alternative to glass (Figure 2.10). Production of poly (methyl methacrylate) increased 1200 per cent during the period 1940-43 due to the escalation in production of aircraft (Kline, 1944). 

Trade names and synonyms Acrylite Acrylplast , Altuglas , Lucite , Perspex , Plexiglas , Plazcryl , poly (methyl 2-methylpropenoate) (lUPAC name)... 

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