Viscoelastic properties of amorphous boron trioxide

Creep compliance measurements have been made on low moisture and bubble-fre e amorphous boron trioxide, B2O3, over the temperature range from 250 degre esC to 320 degreesC in an attempt to determine the existence and form of mo lecular moieties in the material. No polymeric modes were found to be prese nt in the retardation spectrum, L(tau), which was calculated from the recov erable compliance measurements. Based on the shape of L(tau) and the presen ce 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 existen ce of a network. (C) 2001 Elsevier Science B.V. All rights reserved.