  Dielectric spectroscopy was carried out on polycyclohexylmethacrylate (PCHMA)
and its blend with poly-alpha-methylstyrene (PaMS) as a function of temperature
and pressure. When measured at conditions whereby the local segmental
relaxation time for the PCHMA was constant, the dispersion in the loss spectra
had a fixed shape; that is, the relaxation time determines the breadth of the
relaxation time distribution, independently of T and P. This result is known
for neat materials and could be observed for the blend herein due to the
nonpolar character of the PaMS and the degree of thermodynamic miscibility of
the blend.
