The PVDF reference article from the English Wikipedia on 24-Jul-2004
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PVDF

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PVDF, or PolyVinyliDine Fluoride, is a highly non-reactive and pure thermoplastic fluoropolymer. It is also known as KYNAR®.

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PVDF is very expensive; its use generally reserved for applications requiring the highest purity, strength, and resistance to solvents, acids, bases and heat. It is available as piping products, sheet and plate. It can be injection molded and welded and is commonly used in the chemical, semiconductor and medical industries.