The Viscoelastic Relaxation Mechanism of Inorganic Polymers: Amorphous Selenium

摘要

Selenium is subject to bond interchange in the melt; this is seen from the existence of a dynamic equilibrium between rings and chains. In order to determine whether bond interchange extends down to the glass transition region, the viscoelastic properties of several samples of various chain length were studied. The chain length could be varied by the addition of iodine to the melt, and the iodine content correlated with the chain length by the application of a modified version of the previously developed theory of equilibrium polymerization. The results indicate that the relaxation behavior is molecular weight dependent in exactly the same way as in normal organic polymers, which implies that bond interchange is, for all practical purposes, absent in that temperature range. (Author)