HREELS analysis of the interface formation between vacuum evaporated aluminium and three polymer substrates poly(vinyl alcohol), poly(acrylic acid) and poly(ethylene terephthalate)

Abstract

In order to compare the reactivity of different chemical functionalities against metal (aluminium) deposition on polymer surfaces, spectroscopic vibrational data recorded from different polymers were gathered and compared. Three polymers, poly(vinyl alcohol) (PVOH), poly(acrylic acid) (PAA), and poly(ethylene terephthalate) (PET) were aluminized under ultra-high vacuum with submonolayer incremental steps. High resolution electron energy loss spectroscopy (HREELS) was used to characterize the interface formation at each incremental step. Many vibrational bands were observed for each polymer; their study (intensity and frequency) during metallization gave a rather rich picture of the interfacial reaction mechanisms in terms of first reaction sites and compounds formed. On the PET sample, for example, we could distinguish aromatic and aliphatic C-H vibrations, observe the C=O and C-O-CH2 parts of the molecule, and study their changes during the metallization process.