Radio frequency plasma polymer

XPS data, on the other hand, showed that the ETC AT treatment of Ar + CF4 and Ar + C2F4 yielded just as good, if not better, fluorination of PET fibers than radio frequency plasma treatment with these gases [14,15]. These examples clearly demonstrate that polymerizable species in plasma polymerization are not photon-emitting species in most cases. This is in accordance with the growth and deposition mechanism based on free radicals, which account for the presence of large amount of dangling bonds in most plasma polymers. 

Fig. 3.1 Apparatus used for producing a gradient with radio frequency plasma discharge (RFPD). The RF plasma appears between the RF hot plate and the grounded plate. The plasma is exposed to the polymer surface at various lengths of time as regulated by the movable cover30,55...

McCord M G, Hwang Y J, Qui Y, Hughes L K and Bourham, M K, Surface analysis of cotton fabrics fluorinated in radio-frequency plasma . Journal of Applied Polymer Science, 2003, 88(8), 2038-2047. 

Germanium internal reflection elements (IRE, 50x20x3, 45 aperture) were polished twice with 0.3 urn alumina polish, rinsed with distilled water, rinsed with ethanol, and then cleaned in a radio frequency plasma discharge. The IRE s were pulled vertically (dip coated) from the polymer solutions at 3mm/min. Each coated IRE was dried in a vacuum oven at 60 C for at least 4 hours, and was stored under vacuum until use. 

Polymer-film modified electrodes are used for a variety of applications, such as electrocatalysis (5-8). analysis (9.10). and more recently for their permselectivity characteristics (11-1H). These polymer films are formed by casting the film on an electrode surface (12), using radio-frequency plasma (15), or by electropolymerization (13.16.17). Alternatively, a polymer film 1s formed as a discrete membrane Eind subsequently applied to an electrode (18). The use of both cast and discrete membrane films... 

Wang, C., Wang, C., 2010. Surface pretreatment of polyester fabric for inkjet printing with radio frequency plasma. Fibers Polym. 11 (2), 223-228. 

A detailed study of the physical and electrochemical properties of electrodeposited poly(vinylferrocene) has been presented 2 4 . -pije effect of different solvents on the electrochemical response of this polymer, deposited from a radio-frequency plasma, has been reported . The poly-(vinylferrocene/ferricinium) system has also been proposed as a reference electrode for non-aqueous media . 

Poljraer surfaces can be easily modified with microwave or radio-frequency-energized glow discharge techniques. The polymer surface cross-links or oxidizes, depending on the nature of the plasma atmosphere. Oxidizing (oxygen) and nonoxidizing (helium) plasmas can have a wide variety of effects on polymer surface wettability characteristics (92). 

Physical methods include plasma treatments, UV irradiation, corona discharge, and flame treatment. Among these, plasma treatment is widely used for the surface modification of synthetic polymers. Plasma can be obtained by exciting gases into an energetic state by radio frequency, microwave, or electrons from a hot filament discharge. Generation of plasma requires a vacuum, which normally poses several... 

In 1972, Liepins and Sakaoku [7] reported that polymeric powders were formed nearly exclusively in the radio frequency reactors shown in Figures 8.12 and 8.13, in which an organic vapor was introduced into the glow discharge of a carrier gas. The monomers that formed powders nearly exclusively and the yield of powder formation are summarized in Table 8.1. Monomers that did not form powders exclusively (i.e., formed plasma polymer in the form of a film or a film with powders) are shown in Table 8.2. The significant points about these experiments are as follows ... 

The internal stress of plasma polymers is dependent not only on the chemical nature of monomer but also on the conditions of plasma polymerization. In the plasma polymerizations of acetylene and acrylonitrile, apparent correlations are found between and the rate at which the plasma polymer is deposited on the substrate [2], as depicted in Figure 11.3. The effect of copolymerization of N2 and water with acetylene on the internal stress is shown in Figures 11.4 and 11.5. The copolymerization with a non-polymer-forming gas decreases the deposition rate. These figures merely indicate that the internal stress in plasma polymers prepared by radio frequency discharge varies with many factors. The apparent correlation to the parameter plotted could be misleading because these parameters do not necessarily represent the key operational parameter. 

Ihara and Yasuda investigated the deposition behavior of methane in the medium-sized tubular reactor with 13.56 MHz radio frequency discharge [2]. They observed that the critical WjFM value, WjFM), for methane was 8GJ/kg, and nearly 100% of monomers were converted to the plasma polymer beyond this critical WjFM value. As shown in Figure 19.5, the critical WjFM value of perfluoropropene in the small reactor is around 6GJ/kg and the DjFM is 15%, and the corresponding value in the medium is around 4GJ/kg, and the maximal conversion is around 30%. In the large reactor, (WIFM) is about 1 GJ/kg and the maximal DjFM is 20%. The lower value of the critical WjFM for C3F6 than that for CH4 is explained in Chapter 7. 

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