Please forward this error when i copy from a pdf it pastes as garbage to sharedip-10718044127. This article is about the transparent plastic sometimes called acrylic glass.
The same material can be used as a casting resin, in inks and coatings, and has many other uses. It is often preferred because of its moderate properties, easy handling and processing, and low cost. PMMA is sometimes able to achieve high scratch and impact resistance. The first acrylic acid was created in 1843. ICI registered the product under the trademark Perspex.
Rohm 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. Both Perspex and Plexiglas were commercialized in the late 1930s. In the United States, E. During World War II both Allied and Axis forces used acrylic glass for submarine periscopes and aircraft windshields, canopies, and gun turrets. Airplane pilots whose eyes were damaged by flying shards of PMMA fared much better than those injured by standard glass, demonstrating better compatibility between human tissue and PMMA than glass. It is a common mistake to use “an” instead of “en”.
PMMA can also be performed. The forming temperature starts at the glass transition temperature and goes up from there. PMMA to overcome its brittle behavior in response to applied loads. Scratches may easily be removed by polishing or by heating the surface of the material.
However, the pulsed lasercutting introduces high internal stresses along the cut edge, 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. In the majority of applications, it will not shatter. Rather, it breaks into large dull pieces. PMMA in any shape, from a mold.