Cobalt Replacement In Unsaturated Polyester Resins; Going For Sustainable Composites

As alternative to cobalt based catalysts, various other catalysts based on manganese, iron and/or copper were developed for curing unsaturated polyesters in styrene with a hydroperoxide. This development is based on the simultaneous tuning of the redox chemistry taking place on the transition metal as well as on the ligand. From a mechanical point of view, based on DMA, these systems behave as drop-ins. Employing these systems, unsaturated polyesters diluted in vinyl esters can also be cured. This makes cobalt-free and styrene- free unsaturated polyesters possible.