Effects of a Distribution of Volume Relaxation Times in the Annealing of Bse Glass

The inAu ence of a di s tribution of relaxation times is studied in annealing ex pe rim ents . A twore la xation tim e mode l is proposed , whic h pe rmits th e ca lculatio n of the di stribution o f relaxation times from the c rossover data of Spinn e r and Napolitano as we ll as that of Ritland. This mode l al so characte ri zes th e struc ture of any glass in te rms of two parame te rs . Thus , qu enc hed equilibrium as well a s none quilibrium glass we re compared with rat e cooled glasses with respect to the ir behavior upon furth e r annealing as well as the ir condu ctivit y at low te mperatures with excelle nt agree ment. Boros ilica te c rown glass was found to have a narrow di s tribution of re laxation times which is partic ular to associated liquid monomers rathe r than pol yme rs. The result s can be explained in te rms of a topological model for the di s tribution of re laxation tim es. The te mpe rature de pendence of th e viscos it y is due to a true ac tivation ene rgy rathe r than a free volume e ffec t.