Fluorocarbon Films

Optical Properties. Teflon FEP fluorocarbon film transmits more ultraviolet, visible light, and infrared radiation than ordinary window glass. The refractive index of FEP film is 1.341—1.347 (74). 

Teflon FEP—Fluorocarbon Film, bulletin T-5A, Optical, E. I. du Pont de Nemours Co., Inc., Wilmington, Del. 

Optical Properties and Radiation Effects. Within the range of wavelengths measured (uv, visible, and near-ir radiation), Teflon PFA fluorocarbon film transmits slightly less energy than FEP film (29) (Table 6). In thin sections, the resin is colorless and transparent in thicker sections, it becomes translucent. It is highly transparent to it radiation uv absorption is low in thin sections. Weather-O-Meter tests indicate unlimited outdoor life. 

A new concept in graphite disks includes addition of a fluorocarbon film barrier between the process and the disk, and is termed a duplex disk. These disks are suitable for temperatures to 392°F, with accuracies as just mentioned. 

J.X. Tang, Y.Q. Li, L.R. Zheng, and L.S. Hung, Anode-organic interface modification by plasma polymerized fluorocarbon films, J. Appl. Phys., 95 4397-4403 (2004). 

The critical surface tension has been evaluated by means of advancing contact angle measurements for water, various hydrocarbon liquids and for plasma polymerized fluorocarbon films " " . The most comprehensive, however, is that of Yasuda... 

Kelly, N. A Characterization of Fluorocarbon-Film Bags as Smog Chambers, Environ. Sci. Technol., 16, 763-770 (1982). 

Focusing collectors are usually cast acrylic Fresnel lenses, or mirrors of aluminized polyester film in frames of aluminum. These reflectors are either enclosed in a bubble of poly(vinyl fluoride) film, or under polycarbonate glazing, which may be covered with a fluorocarbon film to reduce the reflectivity. The absorbers for active systems are copper or aluminum since the temperatures are too high (325—370°C) for plastics. The frames, however, can be molded ABS, high density polyethylene or polyurethane, either solid or structural foam. Polybutylene or chlorinated PVC can be used for piping hot water, and tanks can be made of either reinforced polyester or blow- or rotational-molded, high density polyethylene (12—15). 

Reversible bonding of PDMS to PMMA was also achieved [177,178,364]. A PDMS replica containing microchannels (< 100 pm deep) was sealed against a PMMA plate (or a PDMS replica of it) that had deep (300-900 pm) solution reservoirs machined in it [1042]. PDMS was also sealed against a patterned hydrophobic fluorocarbon film [179]. 

Fig. 13. Effect of fluorocarbon film deposition in CF4—H2 mixtures on the F concentration in the gas phase (reprinted with permission from J. Appl. Phys., 62 (1987) 662 [63]).

Fig. 14. Fluorocarbon film thickness on Si and Si etching rate as a function of the gas mixture in CF4—H2 plasmas (reprinted with permission from Mat. Res. Soc. Symp. Proc., 98 (1987) 229 [64]).

Postdeposition plasma modifications to the plasma polymer of TMS have been seen to greatly improve bonding to various primers and paints [18-20]. One particular system has been observed to have tremendous adhesion between plasma-coated A1 alloy panels and paint applied to them. This system involves cathodic DC plasma deposition of a roughly 50-nm primary plasma polymer film from TMS onto a properly pretreated alloy substrate, followed by the deposition of an extremely thin fluorocarbon film by DC cathodic deposition of hexafluoroethane (HFE). It was the superadhesion aspect of this particular system that triggered the series of ESR studies [3,21]. 

Asphaltic membrane is adversely affected by solvent. A layer of fluorocarbon film such as Tedlar or Kynar 2 mils thick, is placed on top of the membrane in such exposures. 

Table II. Effect of Monomer on the Distribution of Functional Groups in Plasma-Polymerized Fluorocarbon Films... 

The films deposited in various substrates after plasma treatment in the presence of perfluorinated olefins were subject to partial removal with extraction. Generally, after extraction, the fluorine to carbon ratio, determined through XPS analysis, decreased to 0.2 1 to 0.3 1 regardless of the applied power and residence time used during the fonnation of the film. In all cases a moderate but consistent amount of oxygen was detected in the fluorocarbon film. The oxygen to carbon ratio 0.12 1 to O.l t before extraction and 0.08 1 to 0.1 1 after extraction. 

Figure 11. A cylindrical sector defect in a fluorocarbon film grown over a scratched glass surface...

Excluding glass, the only commercially available, transparent, UV screening plastic films which have been Identified are fluorocarbon films, Tedlar (Du Pont), and PMMA films, Acrylar (3M Co.). 

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