TOF SIMS and XPS study of the interaction of aminosilanised E-glass fibres with epoxy resins. Part I: Diglycidyl ether of bisphenol S

Abstract

The interaction between hydrolysed γ-aminopropyl-triethoxysilane (HAPS) and the epoxy resin, diglycidyl ether of bisphenol S (DGEBS), with E-glass fibres has been studied by means of time-of-flight secondary ion mass spectrometry (TOF SIMS) and X-ray photoelectron spectroscopy (XPS). The contamination of the as-received, apparently non-silanised or non-coupled, E-glass fibre surface by a patchy monomolecular layer of HAPS has been demonstrated. Its influence on the chemisorption of an epoxy resin on to the fibre surface was also studied. After treatment of the non-coupled fibres with a fresh aqueous HAPS solution, the formation of a multilayer of HAPS on the fibre surface with the amino groups at the outer surface and in a non-ionised from available for coupling with the epoxy groups of DGEBS was apparent. On the DGEBS coated HAPS-coupled fibre surface, the formation of a coupling reaction product between the amino groups of the HAPS deposit with the epoxy groups in the DGEBS deposit during the treatment has been demonstrated. Because of the presence of the HAPS contaminants, a similar result was also obtained from the DGEBS coated non-coupled fibre surface. This provides direct evidence for the interfacial microchemistry which explains the adhesion of the non-coupled fibres to an epoxy resin matrix implicit in a similar interfacial shear strength to that of the HAPS-coupled ones (Comp. Sci. Technol., 48 (1993) 89–96).