Monomers such as tetrafluoroethylene and
chloro-trifluoroethylene can be copolymerized with a variety of different vinyl
monomers to yield polymeric materials that are amorphous in structure and have
excellent solubility in common organic solvents. Reactive functionality can
also be introduced into these copolymers through the introduction of suitably
functionalized monomers during the polymerization process. Polymers of this
type have excellent room-temperature processability and can be readily
fabricated into coatings and films on a wide variety of substrates. Using TFE
as the monomer enables some of the inherent characteristics of PTFE to be
retained in the final copolymer (TFEC) such as excellent weatherability and
dirt resistance, but with the added advantage of the improved ease of
processing. The properties of common fluoropolymers are summarized in Table 1.
Figure 1 summarizes the structural components of the newly developed TFEC and
their role in providing performance properties to a finished coating. The
introduction of alkenyl groups into TFEC enables the hydrosilylation
crosslinking that is widely used today in many common reactive silicone
materials. In terms of fluoro resin functionality the TFE unit contributes
excellent weatherability, chemical resistance and anti-corrosion properties,
while incorporation of vinyl monomers enables modification of the co-polymer
characteristics to provide important properties such as transparency, solvent
solubility and compatibility with pigments and polymer additives. The TFEC
coating can be cured with conventional Si-H-containing crosslinkers in the
presence of a platinum catalyst, as shown in Figure 2.