Challenging the Kauzmann paradox using an ultra-stable perfluoropolymer glass with a fictive temperature below the dynamic VFT temperature

Ultra-stable fluoropolymer glasses were created using vacuum pyrolysis deposition that show large fictive temperature T(f) reductions relative to the glass transition temperature T(g) of the rejuvenated material. T(f) was also found to be 11.4 K below the dynamic VFT temperature T(VFT). Glass films with various thickness (200–1150 nm) were deposited onto different temperature substrates. Glassy films were characterized using rapid-chip calorimetry, Fourier-transform infrared spectroscopy and intrinsic viscosity measurements. Large enthalpy overshoots were observed upon heating and a T(f) reduction of 62.6 K relative to the T(g) of 348 K was observed. This reduction exceeds values reported for a 20-million-year-old amber and another amorphous fluoropolymer and is below the putative Kauzmann temperature T(K) for the material as related to T(VFT). These results challenge the importance of the Kauzmann paradox in glass-formation and illustrates a powerful method for the exploration of material dynamics deep in the glassy state (T(f) < T < T(g)).