The aim of this work was to understand the reactions involved in the photocrosslinking processes of a alpha,omega-unsaturated copolyamide foreseen as a new UV-curable powder coating. The crosslinking reaction was photoinitiated with benzophenone. In this paper, the photochemical reaction between benzophenone and several model compounds was investigated. The model compounds contained functional groups which could be present in copolyamide. The products resulting from UV curing were identified using a combination of high-resolution mass spectrometry and MS(n) experiments. The characterization of the products allowed localization of the hydrogen abstraction by the type II photoinitiator during UV curing and, consequently, the determination of the reactive sites of the unsaturated polyamide chain which were involved in the photochemical reaction.
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