The scaling form presented by Nagel and coworkers for the α-process in supercooled liquids is re-examinated in the light of new dielectric relaxation data. Several data sets are compared in order to check quantitative relationships implied by the scaling and to examine the reliability of dielectric measurements. The analysis shows that no master curve can be obtained by the procedure suggested. Furthermore, we find that the scaling may obscure peculiarities in the dielectric response, e.g., for the glass formers salol and tricresyl phosphate additional relaxation processes are suppressed. We conclude that the spectral shape of the α-process remains an open question.

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Results of a study of the solution polycondensation of seven aromatic diamines with bisacid A2 are reported. The polymer of bisacid A2 with hexamethylene diamine is also synthesized. An evaluation of the polymers based upon wide angle X-ray scattering, infrared analysis, differential scanning calorimetry, thermogravimetric analysis, and mechanical properties has been carried out. Two of the polymers have been wet spun into fibers. KEY WORDS Polycondensation / Fibers / Polyamide / Mechanical Properties / Bisacid A2 / X-Ray Diffraction / Aromatic Diamine / Calorimetry / * Nylons nA2, where n stands for the number of C atoms in the aliphatic diamine chain.