Polymer surface fluorination

Surface engineering by means of fluorination is an effective way to change surface properties, and is used for both polymer surfaces and inorganic substrates. Polymer surface fluorination has been around a long time. The first patent we know of dates back to 1938,1 but it was only in the 1970s that the introduction of several major industrial applications led to a rapid acceleration in development. 

However, the fact that industrial applications of polymer surface fluorination employ a fluorine/nitrogen mixture as the fluorinating agent complicates matters because fluorine gas is toxic, may explode when brought into contact with organic substances, and causes severe bums on human tissue. Moreover, the use of fluorine requires highly qualified personnel and special safety systems. 

It is appropriate at this point to recall that XeF2 was originally considered to be exotic and was used only as laboratory chemical in very small quantities. While direct polymer surface fluorination with a gaseous F2/N2 mixture was already in use for several significant commercial applications. 

However, one should not forget that apart from the complexity of the synthesis fluoropolymers are very expensive. For example, the price of fluoro-rubber is more than 30-fold that of an ordinary rubber such as butadiene-styrene (SBR) or ethylene-propylene (EPDM). Cost was one of the factors that gave impetus to research polymer surface fluorination, with the object of imparting the properties of fluoropolymers to the surfaces of less expensive polymers without changing their bulk properties. 

It is believed that polymer surface fluorination proceeds via a free radical mechanism, where fluorine abstracts hydrogen atoms from the hydrocarbon, and fluorine atoms are substituted.11 Of course, the precise conditions depend on the nature of the polymer in question and the surface properties required. 

POLYMER SURFACE FLUORINATION WITH XENON DIFLUORIDE... 

The XeF2 polymer surface fluorination technique can be easily applied at manufacturing companies that have no experience in dealing with fluorine. 

Corbin, G.A., Cohen, R.E. and Baddour, R.F., Kinetics of Polymer Surface Fluorination Elemental and Plasma Enhanced Reactions , Polymer, 23, 1546-1548 (1982)... 

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