Viscoelastic properties of amorphous boron trioxide

Creep compliance measurements have been made on low moisture and bubble-free amorphous boron trioxide, B2O3, over the temperature range from 250°C to 320°C in an attempt to determine the existence and form of molecular moieties in the material. No polymeric modes were found to be present in the retardation spectrum, L(τ), which was calculated from the recoverable compliance measurements. Based on the shape of L(τ) and the presence of liquid flow, it is concluded that boron trioxide behaves similarly to a low molecular weight glass former or a tightly cross-linked, but labile, network. Additional evidence is given that appears to rule out the existence of a network.