摘要:
An activator composition for accelerating hardening and achieving cure-through-volume of cyanoacrylate adhesives) comprising; (a) one or more compounds selected from the group consisting of :(i) pyrazine; or a pyrazine derivative; said pyrazine derivative being pyrazine substituted with at least one electron-releasing group; (ii) pyridine N oxides substituted with at least one electron-releasing group; or (iii) 2,6 pyridines being pyridines substituted in the 2- and 6-positions by substituents, at least one of the substituents being electron-releasing provided that both substituents are not methyl; and (b) a volatile solvent carrier for the compound.
摘要:
An activator composition for accelerating hardening and achieving cure-through-volume of cyanoacrylate adhesives) comprising; (a) one or more compounds selected from the group consisting of :(i) pyrazine; or a pyrazine derivative; said pyrazine derivative being pyrazine substituted with at least one electron-releasing group; (ii) pyridine N oxides substituted with at least one electron-releasing group; or (iii) 2,6 pyridines being pyridines substituted in the 2- and 6-positions by substituents, at least one of the substituents being electron-releasing provided that both substituents are not methyl; and (b) a volatile solvent carrier for the compound.
摘要:
A method of forming a gasket in situ between two components which includes injecting into a groove in at least one of said components a curable composition including:one or more free-radical polymerizable vinyl esters, and ingredients of a rapid free-radical cure system therefor,the cure system being inactivated prior to injection of the composition,and the composition having a viscosity at 25.degree. C. in the range from 200 to 500,000 mPas;and permitting the composition to cure.The composition can be a two part composition wherein the first part contains a prepolymer, monomer and activator and the second part a prepolymer, monomer and activator. The composition can also include two expansion reactants, each in a separate part of the composition prior to injection, which react to form a gas in situ in the composition. The gasketing composition is suitable for use in engines and other machines e.g. in industrial manufacturing plants.