Journal of Polymer Science Part B: Polymer Physics, Vol.35, No.12, 1887-1897, 1997
A Rigorous Comparison of Theoretical Autocorrelation Functions with Dielectric-Relaxation Parameters for the Alpha-Process of Polymers
Recently, tables of parameters used to represent experimental dielectric relaxation data as well as autocorrelation functions have become available. The experimental and autocorrelation function data were represented with the Havriliak-Negami function using rigorous statistical techniques. These tables include not only parameters and their temperature dependencies, but also the confidence intervals for all of the parameters. The important parameters for this work are the two shape parameters, alpha and beta, which represent the width and skewness of the relaxation process, respectively. A comparison is made between the experimental data and several autocorrelation functions by calculating the minimum distance (in units of standard deviations) between the experimental values of alpha beta parameters for a specific polymer and the alpha beta parameters corresponding to the autocorrelation functions reported in these tables. Quantities derived from these minimum distances (a distribution function and an error function) are reported for each of the autocorrelation functions. These results are discussed in terms of the basic assumptions of the mode coupling theory.