Vinylidene fluonde based

Replacement of a vinylidene fluonde unit by an e ylene or propylene unit in a locally perfluonnated cham environment greatly reduces the acidity ot the methylene hydrogens Copolymers of TFE and propylene are therefore considerably more resistant to bases and polar solvents than VDF-based elastomers TFE and propylene form a highly altematmg structure... 

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