3]] + bpy 1 h 15 min 3 h 5 h (a) The drying time was measured in a clear varnish based on Uralac AD 152 WS-40 from DSM Resins (a medium oil alkyd resin based on soy-bean oil, 47% oil) (b) Commercial cobalt combination drier (c) Commercial manganese combination drier (d) Commercial manganese drier based on manganese 2-ethylhexanoate and bipyridine
First of all, the performance of the commercial cobalt driers and manganese driers were analyzed; the effect of bipyridine inclusion on the reactivity of these driers has been investigated and the results compared with the actual effectiveness of these systems in real alkyd paints.
3]]/bpy and the results obtained for the commercial combination of cobalt driers and manganese driers are listed in Table 2.
The rates of disappearance of EL in the reaction with dioxygen, as catalyzed by the commercial cobalt driers and the manganese driers, correlate reasonably well with the actual drying times as found in the real alkyd paints.
3]] also functions as a very good drying catalyst in a real alkyd system, better than conventional manganese driers and comparable with, or even better than a cobalt combination drier.