Direct fluorination—Useful tool to enhance commercial properties of polymer articles

Fundamental features and industrial applications of the direct fluorination of polymers are reviewed. Fundamental features of the direct fluorination of a set of polymers, such as polystyrene, polyethyleneterephthalate, poly(2,6-dimethyl-1,4-phenylene oxide), PMMA, LDPE (two types), HDPE (six types), polyvinyltrimethylsilane, poly(4-methyl-pentene-1), polyimide Matrimid 5216^®, polysulfones, polyetheretherketone, polycarbonatesiloxane, polysulphone-polybuthadiene block-copolymers, polypropylene, PVF, PVDF, etc. are described. Influence of composition of the fluorinating mixture (F₂-He-N₂-O₂-HF), fluorine partial pressure, temperature and fluorination duration, on the rate of formation of the fluorinated layer and the chemical composition, density, refraction index, surface energy, gas separation properties and friction coefficient of fluorinated layer have been investigated. Processes of formation and termination of long-living and short-living radicals and grafting of acrylonitrile to fluorinated polymers have been studied. Industrial applications of the direct fluorination to enhance the commercial properties of polymeric goods, such as separation factor of polymeric membranes for gas separation, barrier properties of polymer vessels, pipes and packagings, adhesion, printability, wetting and transparency in visible and IR are reviewed.