FORMATION OF SI-C BONDS AT THE SURFACE OF SILICA AND GLASS-FIBERS

Amorphous silica and glass fibres have been derivatised at the Surface with fluorinated aromatic molecules. The resultant materials have bee n analysed by various techniques including thermogravimetry (TG), dyna mic contact-angle analysis and, to a large extent, mass spectrometry. The last method was found to be particularly useful for the analysis o f the surface of silica materials. Two different experimental routes w ere used to produce a -CH2C6F5 modified surface. Further modifications to these materials involved attempted nucleophilic replacement of flu orine of the pentafluorobenzyl group with phenolate and benzoate anion s. The materials were relatively hydrophobic and have potential use in glass-fibre composites by prevention of water ingress along the inter face of the material.