Chemical Properties
The most valuable property is low permeability to a wide
range of gases and vapors. The polymer is not health stable.
Chemical Properties
The polymerization of vinyl fluoride has been reported to be difficult but the
polymer is available in film form. Details of the polymerization techniques
used have not been disclosed. The polymer may be obtained by polymerization of vinyl fluoride in the presence of water, using benzoyl peroxide as
initiator at 80°C and pressures up to 100 MPa (1000 atmospheres).
Poly(vinyl fluoride) (PVF) resembles poly(vinyl chloride) in chemical properties but its mechanical properties are generally superior because of its
much greater ability to crystallize. The fluorine atom is sufficiently small to
permit the molecules to pack in the planar zig-zag fashion of polyethylene.
Thus films of poly(vinyl fluoride) have high tensile and
impact strengths and outstanding resistance to flexural fatigue.
The polymer is insoluble below about 100°C but dissolves above this
temperature in certain highly polar solvents such as dimethylformamide. The
polymer is also highly resistant to hydrolysis.
Although poly(vinyl fluoride) is more heat resistant than poly(vinyl chloride), it has a tendency to eliminate hydrogen fluoride and instability at
processing temperatures makes handling difficult. The weather resistance of
poly(vinyl fluoride) is exceptionally good and the film is used particularly for
outdoor applications such as glazing in solar energy collectors.
Definition
ChEBI: A polymer composed of repeating fluoroethyl units.
Application
The linear macromolecule of polyvinyl fluoride (PVF) is based on the monomer unit: [—CH2 —CHF—]n. PVF which is only used industrially as a thin film, exhibits good resistance to abrasion and resists staining. It also has outstanding weathering resistance and maintains useful properties from –100 to 150°C.
Industrial uses
Polyvinyl fluoride is a tough, partially crystallinethermoplastic material that has a highersoftening temperature than polyvinyl chloride.Films and sheets are characterized by highresistance to weathering.
Films are used in industrial and architecturalapplications. Coatings, for example, onpipe, are resistant to highly corrosive media.
