Fourier self-deconvolution (FSD) is used to enhance the spectral resolution of Fourier transform infrared results obtained from thick solution-cast films of bisphenol-A-polycarbonate-poly(dimethylsiloxane) blends and random block copolymers. Despite the severity of band overlap in the region from 1300 to 1200 cm−1, accurate determinations of bulk composition are made from the deconvolved absorbance (transmission mode) spectra of eleven blends and three random block copolymers. With compositions expressed in terms of each component's relative concentration, these results are used to develop a multicomponent Beer's law relationship that is verified through the determination of appropriate homopolymer absorptivities. Fourier transform infrared attenuated total reflectance results are compared to the multicomponent Beer's law relationship in an effort to quantitate the surface excess of siloxane 0.004–1.6 µm from the air/solid interface.
The retention behavior of a heterogeneous group of solutes has been examined on seven different stationary phases under isothermal and temperature-programmed conditions. Both AH, (enthalpy of solute vaporization from the stationary phase) andAS, (entropy of solute vaporization from the stationary phase) valbes were determined for each solutestationary phase combination under isothermal conditions. Both program rate and carrier gas velocity were shown to affect solute elution order. Unless these and other experimental factors discussed are controlled, column equivalency studies based on solute elution order have dubious value.
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