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MMA is a raw material for the manufacture of other methacrylates. These derivatives include ethyl methacrylate (EMA), butyl methacrylate (BMA) and 2-ethyl hexyl methacrylate (2-EHMA). Methacrylic acid (MAA) is used as a chemical intermediate as well as in the manufacture of coating polymers, construction chemicals and textile applications.
Methacrylic acid, abbreviated MAA, is an organic compound with the formula CH 2 =C(CH 3)CO 2 H. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor.
Soft contact lenses are often made of a related polymer, where acrylate monomers containing one or more hydroxyl groups make them hydrophilic. In orthopedic surgery, PMMA bone cement is used to affix implants and to remodel lost bone. [41] It is supplied as a powder with liquid methyl methacrylate (MMA).
The monomer is a viscous liquid with a pungent odour. The first polymeric form of methacrylic acid was described in 1880 by Engelhorn and Fittig. The use of high purity monomers is required for proper polymerization conditions and therefore it is necessary to remove any inhibitors by extraction (phenolic inhibitors) or via distillation. [ 2 ]
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Many monomers are purified industrially by distillation, which can lead to thermally-initiated polymerisation. Styrene, for example, is distilled at temperatures above 100 °C whereupon it undergoes thermal polymerisation at a rate of ~2% per hour. [ 1 ]
Acrylic resin is a common ingredient in latex paint (UK: "emulsion paint"). Latex paints with a greater proportion of acrylic resin offer better stain protection, greater water resistance, better adhesion, greater resistance to cracking and blistering, and resistance to alkali cleaners compared to those with vinyl. [2]
The first contact lenses were made of glass, in 1888. Initially the glass was blown but soon lenses were made by being ground to shape. For the first fifty years, glass was the only material used. The lenses were thin, yet reports of injury were rare. In 1938 perspex (polymethylmethacrylate, or PMMA) began to replace glass in contact lens ...