Polyvinylidene fluoride is white powder with its melting point 166-170°C . It has a highly dipolar molecule so that, if the correct morphology is achieved, valuable piezo- and pyro-electric properties result. The desired form is known as the ß phase or Form I, in which the predominantly "head to tail" polymer chains have an all-trans extended planar zig-zag form with the dipoles of adjacent chains parallel to one another.
This is formed from the more common Alpha phase (Form II) by mechanical deformation followed by electrical polarisation at very high electrical fields. It is soluble in some polar solvents such as organic esters and amines. In practice, both uniaxial and biaxial mechanical orientations are used which, after poling, give a different balance of piezo-/pyro-electric properties. It is stable but incompatible with strong oxidizing agents, silica. It can be used for coatings for chemical engineering equipment, electrical cables, high-protection coatings for metal surfaces, etc.
For sterile and general filtration applications, our unique, modified hydrophilic polyvinylidene fluoride (PVDF) membrane with ultra low binding properties, broad chemical and temperature resistance, and high flow rates is an excellent choice.
For the filtration and degassing of solvent-based mobile phases, our portfolio includes an HPLC-certified material available in 0.2 and 0.45 µm, which provides assurance that the filter material will not add artifacts or extractables to the sample for analysis.
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