MEKP Cobalt-Free System (Amine Accelerated)

MEKP Cobalt-Free System is a specially formulated methyl ethyl ketone peroxide product designed to be used exclusively with amine accelerators, eliminating the need for cobalt compounds in the cure system. This system addresses growing regulatory pressure on cobalt salts (classified as CMR — carcinogenic, mutagenic, reprotoxic — under EU CLP regulation) while retaining the convenience and handling familiarity of MEKP. The amine accelerator system typically uses a combination of N,N-dimethyl-p-toluidine (DMPT) and/or DMP-30 to activate the peroxide and achieve ambient cure of UPR and vinyl ester resins. The cobalt-free approach also eliminates the color contributions of cobalt, beneficial for white and light-colored gelcoat and laminate applications. Gel times of 15–30 minutes at 20°C are achievable with optimized amine levels. Minor formulation adjustments — including amine type, amine loading, and potential addition of a Lewis acid promoter — may be needed relative to the cobalt-based system. This product is particularly suited for producers seeking REACH compliance and reduced occupational exposure to cobalt.