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An investigation was conducted of the low-friction and low-wear mechanism of the adsorbed layer formed by dibasic acid ester derivative. First, the film thickness and film density of the adsorbed layer on an iron surface was evaluated by neutron reflectometry. The density of the adsorbed layer formed at 25°C was twice that at 100°C. The macroscale tribological properties of an adsorbed layer formed by dibasic acid ester derivative and its constituent additives (succinic acid and amine) were evaluated using a ball-ondisk tribometer at 25°C and 150°C. The derivative exhibited low friction and wear properties even at high temperature. To clarify the mechanism of the excellent low friction property, nanoscale tribological testing was conducted using an atomic force microscope. The precise measurement indicated that the dibasic acid ester derivative initially exhibits low friction due to generation of metal soap from the amine, and then subsequent friction generates metal soap from the succinic acid that has superior friction reduction performance, which promotes lower friction, especially under low-contact-pressure sliding conditions.

The infrared spectra of polypyrrole contacting with T 20 gas were observed for ca. l00days. After adding T 2 0 (1.2 Ci; isotopic purity: 15%) the band at 2180cm-1 was observed, which is assigned to the N-T stretch. Although the bands at 1560 and 1204 cm-1 were initially strong, they became relatively weak by T P-irradiation. On the other hand, the bands at 1655 and 1400 cm-1 as well as 1700 cm-1 became relatively strong by T Pirradiation. These are explained in terms that the quinonoid-type structure with partially the aromatic-type structure decreases and the structure with probably C = N bonds is formed. It was also found that many carbony defects are formed in both the atmosphere and T P-radiolysis. KEY WORDS Polypyrrole / T /3-Radiolysis / Infrared Spectrum/ Tritium We have studied T /3-radiolysis for such systems as poly(vinyl alcohol) by means of infrared spectroscopy. 1-4 The method is quite useful for clarifying structural changes and decomposed species which _ result from T /3-radiolysis. In the present study we will report the infrared spectra of polypyrrole (PPy)-T 2 0 system, drawing the structural change by T /3-irradiation. PPy prepared by electrochemical oxidation of pyrrole in the presence of inorganic salts includes counter anions as dopant. This is true for PPy prepared by chemical oxidation. That is, doped PPy has cation defects, so-called polaron and bipolaron, which play important role in electronic conductivity. The vibrational study of PPy 5-14 has been widely carried out in relation to the structural change accompanying with electrochemical redox. On the other hand, the infrared spectra of doped PPy 5-11 reveal quite complex features that they depend on the method of oxidation and the kinds of dopant and their concentrations. The similar feature is also seen in reduced PPy. 5 • 7 • 10 • 11 It is also reported 7 • 10 that carbonyl groups, C = N bonds and sp 3 C-H bonds are formed.

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