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Detailed investigations of the interaction of 1,2- diaminoethane with aluminium surfaces have been performed to understand the mechanisms of interphase formation in epoxy-amine/aluminium joints. In particular, it has been shown that both metal bond surface complexes (O-Al … N bonds) and hydrogen-bonded surface complexes (Al-OH … N and CxOyHz … N bonds) can be formed on aluminium surfaces covered with a partly contaminated (hydr)oxide film. However, surface dissolution can only be induced by mononuclear bidentate metal bond surface complexes (chelates), which result from a ligand exchange mechanism between specific hydroxyl sites (η1- and µ2-OH) of the surface and the amino terminations of the molecule. The formation of these chelates weakens the trans Al-O bonds and detachment of the ligand-metal complexes can occur. This mechanism is enhanced by the presence of moisture. In practical epoxy-amine/aluminium joints, the interphase can, thus, be formed by migration of these complexes in the liquid polymeric phase before curing is achieved. [ABSTRACT FROM PUBLISHER]

Although the industrial development of complex metallic alloys (CMAs) and quasicrystals (QCs) has remained quite limited so far, these materials exhibit interesting and sometimes unexpected properties in terms of technological applications. A few selected examples of the most promising properties and trends for potential applications are presented. [ABSTRACT FROM AUTHOR]

The modifications induced on PET, poly(ethylene terephthalate), by an excimer laser irradiation performed below the polymer ablation threshold were studied. The laser treatment of the polymer before aluminum thermal evaporation improved the Al-PET adhesion. The enhancement of the metal-polymer interface strength is attributed to surface morphological changes rather than to chemical modifications of the PET surface. Surface oxidation under UV irradiation was found to degrade the adhesion. [ABSTRACT FROM AUTHOR]