In this study, differences in the surface composition of commercial glass fibre have been characterized as a function of process. The two processes studied were flame attenuation, a high-temperature combustion-assisted process, and continuous filament drawing through a bushing. The techniques used to determine the surface compositions were TOF-SIMS and XPS; the presence of a very thin, boron-depleted silica-enriched layer on the flame-attenuated fibres was most significant. Thermodynamic modeling of the equilibrium vapor pressures at the surface, during fiberization, showed significant differences in the behaviour of Na, B and F species in the two processes. To further test the models, glass fibres were produced under more closely controlled conditions in a laboratory-scale flame attenuation system.
