Ultrasonic evaluation of aging kinetics in amorphous polymer

The physical aging of amorphous polymers induces changes in material properties, which are challenging to detect situ industrial settings. Here, we present a nondestructive nonlinear ultrasonic evaluation technique that enables localized measurements the combined effects temperature and time polymers, without needing remove materials. proposed is demonstrated using commercial grade poly(vinyl chloride) samples supported by analysis wave–material interactions. results show polymer described Arrhenius equation with an effective activation energy 103 kJ/mol over analyzed range.