Polymethyl methacrylate

Polymethyl methacrylate (PMMA) or poly (methyl 2-methylpropanoate) is the synthetic polymer of methyl methacrylate. This thermoplastic and transparent plastic is sold by the tradenames Plexiglas, Limacryl, R-Cast, Perspex, Plazcryl, Acrylex, Acrylite, Acrylplast, Altuglas, Polycast 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 Rohm and Haas Company.
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Noun
1. a transparent plastic used as a substitute for glass
(hypernym) acrylic, acrylic resin, acrylate resin
(hyponym) Lucite, Perspex