Coated Fabrics
Stiffness does not rise gently as it gets colder — it rises exponentially, and the cloth is fine right up until it is not.
— mN·cm
Projected on the exponential stiffening law
Extrapolating an exponential fit far below the measured range is unreliable — near the glass transition the curve steepens sharply and the real crack temperature arrives earlier than this predicts. Fit the coefficient from measurements bracketing the service temperature, and confirm by cold bend test to the governing standard.
Coated Fabric Low-Temperature Flexural Rigidity Predictor — free, with the formula and a worked example, at Textile School.