β Scribed by Philip R. Herrington; George F.A. Ball
No coin nor oath required. For personal study only.
Road asphalt oxidized at 100 and 130Β°C was examined by gel permeation chromatography (g.p.c.) and infrared spectroscopy. Increasing the sample concentration produced a relative increase in absorbance in the early part (region 1) of the g.p.c. chromatogram, suggesting that intermolecular associations are contributing to the chromatogram. However, no correlation was found between the concentration of carbonyl and sulfoxide-containing species (the major oxidation products) and region 1 of the chromatogram. Asphalts oxidized to the same viscosity level at different temperatures gave rise to significantly different g.p.c. profiles, indicating differences in the oxidation product composition.
π SIMILAR VOLUMES
The 3000-PAN-filament tows have been stretched by a constant axial load during heating in air at a constant rate of 7,5"C/min. The extension of the tow begins about the glass-transition temperature (70Β°C). Temperature dependence of the fibre diameter, width of X-ray reflection of the PAN, and endoth