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SYNOPSISThe structure of oriented transfer films of poly (tetrafluoroethylene) (PTFE), previously used as orientation-inducing layers for a variety of materials, was studied. Transmission electron microscopy and X-ray diffractometry were employed to determine the continuity and relative volume of the PTFE films, which were deposited onto glass substrates by friction transfer at controlled temperatures, pressures, and sliding rates. The thickness and continuity of the films were found to increase with increasing temperature and applied pressure. In the range of sliding rates used (0.1-10 mm/s) , no significant correlation between this processing variable and the thickness or continuity was apparent. Transmission electron microscope investigations showed that, generally, the ( 100) plane of the PTFE crystalline unit cell was parallel to the glass surface. 0

Kinetic resolutions with enantioimpure chiral auxiliaries (reagents or catalysts) are considered, and a kinetic treatment for various rate laws is described. A useful parameter, the apparent stereoselectivity factor, is defined and correlated to the enantiomeric excess of the chiral auxiliary. Deviations from the regular laws are possible (asymmetric amplification or depletion). These anomalies have their origins in the same phenomena that cause nonlinear effects in enantioselective catalysis. Asymmetric amplifications have been experimentally observed.