Cell casting is a method used for creating
poly(methyl methacrylate)
Poly(methyl methacrylate) (PMMA) belongs to a group of materials called engineering plastics. It is a transparent thermoplastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Plexiglas, Acrylite, ...
(PMMA) sheets. Liquid
monomer
In chemistry, a monomer ( ; ''mono-'', "one" + '' -mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization.
Classification
Mo ...
is poured between two flat sheets of
toughened glass
Tempered or toughened glass is a type of safety glass processed by controlled thermal or chemical treatments to increase its strength compared with normal glass. Tempering puts the outer surfaces into compression and the interior into tension. ...
sealed with a
rubber
Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...
gasket
Some seals and gaskets
A gasket is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression. It is a deformable material that is used to c ...
and heated for
polymerization
In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer, monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are ...
. Because the glass sheets may contain surface scratches or sag during the process, this traditional method has some disadvantages: among other problems, the PMMA sheets may contain variations in thickness and surface defects. For many applications it has since been replaced by other methods for making PMMA such as
extrusion
Extrusion is a process used to create objects of a fixed cross-sectional profile by pushing material through a die of the desired cross-section. Its two main advantages over other manufacturing processes are its ability to create very complex c ...
, which gives uniform surface features. However, for applications where strength is critical cell casting techniques are still employed in conjunction with stretching, which produces a stronger overall material.
"Cell Casting - A process in which a casting liquid is poured between two plates, usually glass, that have a gasket between them to form a cell to contain the casting liquid; then the resin solidifies, usually through polymerization or crosslinking." - A. Brent Strong
References
Monomers
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