Many fluids exhibiting complex molecular structure or interactions solidify by glass-formation rather than crystallization. This tendency is especially prevalent in polymeric and biological systems where glass-formation is normal rather than exceptional. Glass-formation involves a continuous 14 order of magnitude viscosity increase upon cooling, while crystallization is accompanied by an abrupt juimp to infinite values.The mechanical and transport properties of glasses are largely dictated by thr rate at which the viscosity changes with temperature ('fargility'), and an elucidation of the molecular and thermodynamic factors that influence fragility is crucial for engineering the properties of polymer materials and for designing processes for preserving biological materials.The present paper develops a systematic desription of fragility for general classes of polymer fluids based on direct lattice model computations of the configurational entropy S in combination with the Adam-Gibbs theory of structural relaxation.
, Freed, K.
and Douglas, J.
Fragility of Glass-Forming Polymer Liquids, Journal of Physical Chemistry B, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852482
(Accessed September 21, 2023)