Viscosity-temperature relation based on the evolution of medium-range structures of silica

The viscosity of glass is the most important technological property to manufactures and various applications. Practically, finding an accurate equation express behavior in entire transition temperature range tremendously challenge because it spans more than ten orders magnitude. After a brief review existing empirical equations, this work focuses on correlating silica with evolution medium-range structure, based recently proposed nanoflake model. From new model, constructed, which correctly describes Arrhenius-type η above melting Tm, non-Arrhenius-type from Tm critical Tc. At lower Tc, predicts again for viscous flow increased activation energy. agrees experimental data spanned extremely high low. application shown extend sodium silicate glasses as well.