with 0 5 g of a cobalt naphthenate solution comprising 20 parts methyl methacrylate 20 g one part of a 6 cobalt naphthenate solution in hydrocarbon oil 1 g this formulation was added to an aluminium tube and exposed to a steady stream of argon gas through a syringe needle for 2 minutes n phenyl 2 propyl 3 5 diethyl 1 2 dihydropyridine 0 5 g was added to the formulation under an atmosphere of argon the aluminium tube was then sealed by crimping thus trapping argon gas in the head space above the formulation the aluminium tube was shaken for 10 20 seconds to ensure thorough mixing of the formulation components the adhesive composition was tested as follows samples of the adhesive were squeezed from the aluminium tube and spread onto grit blasted mild steel laps 4 u00d7 1 inches to form a film of approximately 0 1 mm in depth and exposed to air for a measured interval open time then the laps were brought together to form an adhesive joint with 0 5 inch overlap excluding air as a result of activation by exposure to air rapid fixturing was observed and the exact 3 kg fixture times from the.