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Poly(methyl methacrylate) (PMMA) is a synthetic polymer derived from methyl methacrylate. It is a transparent thermoplastic, used as an engineering plastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Hesalite, Plexiglas, Acrylite, Lucite, and Perspex, among several others .
Light microscopic picture of a PMMA-copolymer, made by suspension polymerization SEM-Picture of PMMA-particles, that started to coalesce during suspension polymerization, close to a single bead SEM-picture of a Pac-Man shaped PMMA-copolymer particle, made by suspension polymerization
Block copolymers are made up of blocks of different polymerized monomers. For example, polystyrene-b-poly(methyl methacrylate) or PS-b-PMMA (where b = block) is usually made by first polymerizing styrene, and then subsequently polymerizing methyl methacrylate (MMA) from the reactive end of the polystyrene chains. This polymer is a "diblock ...
The polymers are colorless. This homopolymer is far less important than copolymers derived from methyl acrylate and other monomers. PMA is softer than polymethyl methacrylate (PMMA), [1] It is tough, leathery, and flexible. [2]
The development of coordination polymerization that enables copolymerization with polar monomers is more recent. [4] Examples of monomers that can be incorporated are methyl vinyl ketones, [5] methyl acrylate, [6] and acrylonitrile. [7] Illustrative metallocene-based coordination catalysts
Recycling codes on products. Recycling codes are used to identify the materials out of which the item is made, to facilitate easier recycling process.The presence on an item of a recycling code, a chasing arrows logo, or a resin code, is not an automatic indicator that a material is recyclable; it is an explanation of what the item is made of.
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 manufacture. PMMA lenses were easier to produce so the production of glass lenses soon ended. Lenses made of PMMA are called hard lenses. [5]
The use of the term polymer alloy for a polymer blend is discouraged, as the former term includes multiphase copolymers but excludes incompatible polymer blends. [3] Examples of miscible polymer blends: homopolymer–homopolymer: polyphenylene oxide (PPO) – polystyrene (PS): noryl developed by General Electric Plastics in 1966 (now owned by ...