Polymer plasma-fluorinated

Mention has already been made of the effectiveness of corona or plasma treatment in increasing the influence of subsequent or concurrent polymer treatment. As examples of polymers used in this way, mention can be made of reactive cationic polysiloxane [294] and polymerisation on the fibre of tetrafluoroethylene or hexafluoropropylene [299]. Water repellency was also improved by the fluorinated polymers. Tetrafluoroethylene gave superior shrink resistance this polymer covered the scale edges of the wool, whereas this did not occur with poly(hexafluoropropylene). 

This chapter examines the deposition of fluorinated polymers using plasma-assisted physical vapor deposition. Ultrathin coatings, between 20 and 5000 nm have been produced, using RF magnetron sputtering. The method of coating, fabrication, and deposition conditions are described. 

Tungsten films can be etched easily in fluorine-containing plasma 73,80). If carbon or sulfur is present in the gas atmosphere, oxygen is typically added to prevent polymer and residue formation and to increase the concentration of fluorine atoms. 

Quantitative characterization of plasma-polymer films, especially of ultrathin fluorinated carbon plasma polymer films, has been performed by ToF-SIMS to study changes in the surface composition and molecular distribution. CFX films on silicon and polyethylene terephthalate (PET) substrates were exposed to a pulsed Ar/CHF3 plasma by varying the deposition time from 10-90 s.111-113 The results show differences in film growth and CFX cross linking for the silicon and PET substrates.111... 

Fluorine contamination has been reported in various environments and applications in the past. It has shown up in plasma processing [10-18], as crosscontamination from storage in contaminated containers or with contaminated samples [14,18], and modification of aluminum deposited on fluoropolymer substrates and other polymers having fluorine-based plasma treatments has also been observed [19-21]. Fluorocarbon lubricants have also been noted to modify the oxide structures on aluminum alloys [22,23], and the degradation of AI2O3 catalytic supports has been associated with fluoride conversion during reactions with fluorocarbons [24]. Alloy oxide modification has also been well noted in the presence of fluorine compounds not of the fluorocarbon family [25]. 

Plasma polymerized fluorine-containing polymers Plasma polymerized PMA Polyion complexes Polysulfones POUA PP PPO... 

Some of the most important pre-treatments for plastics were developed in the 1950s. These include the corona and flame treatments for polyolefins [9,10,11,12,13] and the use of sodium complexes for fluorinated polymers [14 - 17]. The plasma treatment was developed somewhat later [18, 19], as was halogenation [20, 21]. 

The most difficult-to-bond plastics family is polytetrafluoroethylene and the other fluori-nated polymers which are the Teflon-like materials. The widespread use of these polymers as coatings for cookware is, of course, based on this property of nonsticking. The conventional methods of etching which can be useful with other difificult-to-bond plastics, like polyethylene and polypropylene, simply do not work on these fluorinated polymer surfaces. Instead the surfaces must be treated with an exotic mixture of metallic sodium and naphthalene in tetrahydrofuran.( 37,i38) More recently, ionized gases (plasma treatment) have also been used successfully. Once treated the surfaces become bondable using conventional two-part liquid... 

The sensitivity of the SFM to changes in crosslink density has been exenqjlified with a plasma deposited hexafluoropropylene (HFP) films (25, 28). This fluorinated polymer plays an inqjortant role in biomedical applications, especially the coating of vascular grafts. Plasma deposited fluoropolymer films promote tight protein adsorption, and are relatively non-reactive to blood platelets (29). As mentioned... 

The most reported effect of plasma is the deliberate alteration of the surface region with new chemical functionalities. Reactive plasma is used to add polar functional groups, which can dramatically increase the surface free energy of the polymer. Plasma can also be used for surface fluorination and silylation, surface-chemical changes, which tend to reduce wettability and superficial strength. 

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