Thermal oxidative degradation reactions of linear perfluoroalkylethers

Abstract

Monoand bis(pentafluorosulfur)-substituted diacetylenes were thermally polymerized in both the bulk liquid and vapor phases at temperatures between 25 and 80 °C. The polymer formed in the liquid phase at 25 °C with SF5Cs=CC=CH was insoluble, while the polymer derived from SF5C^CC^CSF5 at 80 °C was soluble in fluorinated solvents. The vapor phase polymerization of both monomers occurred at 25 °C; the rate of polymerization of SFsC=CC^CH was rapid compared to SF5C^CC^CSF5. The newly formed polymers were characterized by a variety of spectroscopic and physical property measurements.

Studies on degradation mechanisms of lubricants for magnetic thin-film rigid disks

“…The corresponding degradation was not observed with Klubes (with ¾CF(CF 3 )¾CF 2 ¾O¾ units in the molecule). According to various workers [12,30,47], the greater vulnerability of Z-lube towards degradation was attributed to the presence of acetal units in the polymeric chains. Kasai [10] investigated degradation reactions of PFPEs affected by alumina.…”

Optimized structures and proton affinities of fluorinated dimethyl ethers: an ab initio study

“…They are being intensively studied in order to develop a better understanding of the mechanisms of their catalytic decomposition on metal and metal oxide surfaces [1][2][3][4][5][6]. One predominant theory suggests that the reaction is initiated by weak Lewis acid-base interactions at the metal-ether interface [7].…”

Experimental density and PC-SAFT modeling of Krytox® (perfluoropolyether) at pressures to 275MPa and temperatures to 533K

“…The physical properties of PFPEs that make them excellent lubricants at extreme conditions include their low vapor pressure, low surface energy, good thermal stability, and nonflammability [3][4][5]. PFPEs only contain carbon, oxygen, and fluorine atoms and are inert to most chemicals including oxidizing agents, which makes PFPEs compatible in various chemical environments under extreme conditions [6,7].…”