Temperature-Modulated Calorimetry of Polymers with Single and MultipleFrequencies to Determine Heat Capacities as well as Reversible and Irreversible Transition Parameters

摘要

Temperature-modulated differential calorimetry (TMDSC) generated with acentrosymmetric saw-tooth oscillation can be considered to be a sinusoidal modulation with multiple frequencies. Different harmonics of the Fourier series of the heat-flow rate and heating rate of a single sawtooth-modulation can be deconvoluted to extract data pertaining to different frequencies. In order to give the higher harmonics similar amplitudes, a complex but simple-to-program, sawtooth-modulation is generated for the harmonics 1, 3, 5, 7, and 9. In the fashion, a single experiment can produce a frequency-dependent analysis under identical thermal history.