Influence of La sub(2)O sub(3) and Ce sub(2)O sub(3) additions on structure and properties of aluminoborosilicate glasses

Aluminoborosilicate glasses with different amounts of La sub(2)O sub(3) and Ce sub(2)O sub(3) were prepared respectively by the conventional melting-quenching method. The structure, thermal property parameters and dielectric property parameters were investigated by Fourier-Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry and the impedance analyzer. Results from FTIR displayed that the degree of polymerization increased first and then fell down with the addition of La sub(2)O sub(3), and reached the maximum value when the amount was 0.5 mol%. Meanwhile, the degree of polymerization of glasses doped with Ce sub(2)O sub(3) arrived at the largest as the content of Ce sub(2)O sub(3) reached 2.0 mol%. The thermal stability of glasses doped with La sub(2)O sub(3) got enhanced first and then deteriorated, and reached the maximum when the content was 0.5 mol%; Meanwhile, the glasses doped with Ce sub(2)O sub(3) also fluctuated a little. The dielectric constant ( epsilon ) and dielectric loss (tan alpha ) of the samples fell down as the frequency increased. The epsilon and tan alpha of the samples doped with La sub(2)O sub(3) reached the minimum value when the amount got to 0.5 mol%; The epsilon of the glasses doped with Ce sub(2)O sub(3) turned minimum when the amount was zero, but the tan alpha was the smallest when the amount reached 1.0 mol%.