In Search of the Driving Factor for the Microwave Curing of Epoxy Adhesives and for the Protection of the Base Substrate against Thermal Damage

This study used controlled microwaves to elucidate the response of adhesive components to microwaves and examined the advantages of microwave radiation in curing epoxy adhesives. Curing of adhesives with microwaves proceeded very rapidly, even though each component of the adhesive was not efficiently heated by the microwaves. The reason the adhesive cured rapidly is that microwave heating was enhanced by the electrically charged (ionic) intermediates produced by the curing reaction. In contrast, the cured adhesive displayed lower microwave absorption and lower heating efficiency, suggesting that the cured adhesive stopped heating even if it continued to be exposed to microwaves. This is a definite advantage in the curing of adhesives with microwaves, as, for example, adhesives dropped onto polystyrene could be cured using microwave heating without degrading the polystyrene base substrate.

Synthesis and reactivity of rare-earth metal phosphaethynolates

The reactivity and coordination behaviour of OCP− towards three rare-earth elements: Y, Nd and Sm, was investigated. Mono- and bis-phosphaethynolate complexes in different oxidation states were prepared, leading to novel coordination modes of OCP− and ionic intermediates of Sm(ii) in the presence of 18-crown-6 or 2,2,2-crypt.

Diazene sulphonate as a cross-linking agent for polymers with pendant triarylamine hole-conducting units

Diazene sulphonates are readily available compounds which are soluble in water and polar solvents. They strongly absorb the UV-VIS light and they decompose under UV irradiation via radical or ionic intermediates. These properties render them valuable, e.g. for analytical purposes and for photo-printing. In this presentation, it will be demonstrated that polymers with a pendant diazene sulphonate function as cross-linking agents and with pendant aromatic amines as hole-transporters can be considered as useful materials for organic light-emitting device (OLED) technology.