Partially fluorinated thermal

Partially fluorinated X-IP has been used for a number of years as an additive in the inert lubricant PFPE film on the surface of a magnetic hard disk to enhance start/stop durability of PFPE lubricants [29,30]. Recently it has been used as a vapor lubricated film on the surface of the disks [31 ]. In order to avoid the PFPE being catalyzed to decomposition by the slider material AI2O3 (refer to Section 3.4), XI -P was also examined as a protective film on the surface of the magnetic heads [25,32]. The results of CSS tests indicate that the thermal stability of the lubricant was greatly improved in the presence of X-1P, and the thickness of X-1P film on the slider surface has an important influence on HDD lubrication properties. 

As part of an effort to develop high-performance, high-temperature-resistant polymers for microelectronics applications, we also recently described a series of both partially fluorinated and nonfluorinated poly(aryl ether ketone)s containing amide, amide-imide, cyano oxadizole, or pyridazine groups and characterized their thermal and electrical properties.11... 

Girard JP, Savin S (1996) IntercrystaUine fractionation of oxygen isotopes between hydroxyl and non-hydroxyl sites in kaoUnite measured by thermal dehydroxylation and partial fluorination. 

Table 14.5 lists the thermal, electrical, and optical properties of perfluorinated polyimides, along with those of partially fluorinated and unfluorinated polyimides. Because of die flexible structure of the lOFEDA component, the polymer decomposition temperatures and values of perfluorinated polyimides are slightly lower than those of conventional polyimides. This coincides with the results of Hougham et al. who reported that an increase in fluorine content in... 

Table 14.5. Thermal, Electrical, and Optical Properties of Perfluorinated, Partially Fluorinated, and Unfluorinated Polyimides...

These characteristics show that perfluorinated polyimides are promising materials for waveguides in integrated optics and optical interconnect technology. The thermal, mechanical, and optical properties of perfluorinated polyimides can be controlled by copolymerization in the same manner as partially fluorinated polyimides. ... 

Partially fluorinated carbons (CFX) vary in color from gray to dark black. They are thermally less stable, particularly if the fluoride content is 0.2 < x < 0.5. They hydrolyze above 150 C in the presence of moisture and are susceptible to the attack of strong alkalis.12... 

Very recently, a stable 5-thiabicyclo[2.1.0]pentane derivative has been prepared by a thermal reaction. Co-evaporation of solutions of the partially fluorinated fullerene C60F18 and tetrathiafulvalene 109 in toluene led to 110 as the major product, which, on standing in toluene in the presence of CDCI3, reacted further to give the episulfide 111 (Scheme 58) <2003CEJ2008>. The formation of the initial product 110 was formulated via a unique six-electron process involving elimination of fluorine. The second reaction proceeds by elimination of the thioketene derivative 112. 

Partially fluorinated fluoropol5miers are significantly different from the perfluoropol5miers with respect to properties and processing characteristics. For example, perfluoropolymers are more thermally stable but physically less hard than partially fluorinated polymers. Both classes of fluoropolymers are discussed in Ch. 3. 

The chemical nature of the base polymer is an important aspect in membrane development. There has been preference for the thermally stable fluorinated polymers over hydrocarbon polymers. Fluorine-containing polymers, characterized by the presence of carbon-fluorine bonds, are widely used as the base matrices owing to their outstanding chemical and thermal stability, low surface energy, and the ease of modiflcation of various properties by the grafting method. Per fluorinated polymers and partially fluorinated polymers combining hydrocarbon and fluorocarbon structures are excellent candidates as base polymers. For instance, fluorinated FEP has drawn wide attention due to its reasonably good radiation stabiUty [58]. 

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