Desorption Kinetics of Polyether Lubricants from Surfaces
نویسندگان
چکیده
Desorption or evaporation is one of the mechanisms for loss of perfluoropolyalkylether (PFPE) lubricants from the surfaces of data storage media. One approach to minimizing PFPE loss to desorption is the use of lubricants with increasing molecular weight or increasing average chain length. In order to understand the effects of chain length on the lubricant evaporation kinetics we have studied the desorption kinetics of monolayer films of oligomeric ethers with varying chain length adsorbed on the surface of graphite. The desorption preexponents, v, and desorption barriers, E des, have been measured for poly(ethylene glycol) dimethyl ethers, CH3O(CH2CH2O)mCH3, with m = 1, 2, 3, 4, 8 and 10. These are models for the PFPE known as Fomblin Z, which has a structure CF3O(CF2CF2O)x (CF2O)yCF3. The results show that the desorption pre-exponents are independent of chain length and have an average value of v = 1018.7±0.3 s−1. The
منابع مشابه
Adsorption of fluorinated ethers and alcohols on fresh and oxidized carbon overcoats for magnetic data storage.
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