Diacylhydrazines have copper deactivating activity for polypropylene. The multiple regression analysis was made to estimate their activities. That is, sixty-two diacylhydrazines were synthesized and their activities with other physical properties were measured. Among the calculated equations, a second order equation of five physical properties provided the highest accuracy of estimation. Thus, it was shown that the multiple regression analysis can be used as a screening test for copper deactivator efficiency.

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Recently new prediction models taking into consideration of the depletion of ozone layer for polymeric surface finishing materials have been required. This is because the depletion of ozone layer will cause not only the increase of the dangerous shorter wavelength ultraviolet light, but also the change of the deterioration mechanisms themselves. In this paper, new theory containing exponentialy increasing function of photon flux of absorption band is proposed for the predictions of service life of the materials.

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High-speed frictional tests of C/C composites having different densities and the final heat treatment temperatures have been studied. It was found that the wear resistance of C/C composites expressed by the number of tests increased with the increase of the densities at heat treatment temperatures (HTT) 1873 and 2273K, while this value decreased at HTT 2473K when the density was high. It was confirmed from the analysis of the experimental results that the best value for wear resistance of C/C composites was obtained at the average atomic face lattice distance d₍₀₀₂₎ was 0.339 to 0.340nm.

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