We investigate the kinetics and dynamics of the reaction between Na2CO3 and the cathode ray tube panel glass
powder at 923–1173 K. The reaction causes foaming of the glass melt. After the reaction, the Tg decreases with
increasing Na2CO3 content and reaches a minimum value of Tg. However, this Tg value is even lower than that
of the homogeneous bulk glass with the same chemical composition. The lower Tg of the foam glass could be attributed
to inhomogeneous incorporation of Na in the glass, leading to Na-rich domains that cause an overall decrease
of Tg. Remarkably, after 5 min treatment at 1073 K, the Tg drops by 120 K, indicating that the reaction
between Na2CO3 and glass is very fast. Increasing treatment duration causes a slight increase of Tg likely due to
both a more homogeneous Na distribution and the compositional change of the glass as a result of Na2SrSi2O6
crystal formation.