Perhaps one of the most ubiquitous of laboratory items, Parafilm is a product of the American Can Company, consisting of a flexible film, available in several different lengths and widths, that is commonly used for sealing or protecting vessels. Because it is stretchable, moldable, waterproof, odorless, thermoplastic, semitransparent and self-adhering, it can be used to make a temporary flexible seal on open vessels (such as flasks or cuvettes) as one might employ plastic wrap. It can also be used to further seal a lidded container against moisture for long term storage.
It also has gained a reputation among modellers as an ideal masking material for use during airbrushing, due to its lack of tackiness, which can destroy a finish.
Parafilm can also be stretched and rolled to make a sort of rope which has elastic properties similar to those of the film itself, but with greater tensile strength.
Horticulturalists have discovered that Parafilm is ideal for grafting applications. Several grafting styles call for wrapping a graft to hold it together, and sealing it to prevent drying. Parafilm does both, cheaply and effectively. In this context Parafilm is also known as grafting tape.
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