The AFC Accelerators are a unique series of catalysts for anhydride-epoxy and carboxylic acid-epoxy resin systems. They promote exceptionally fast gel and cure at moderate temperatures. AFC Accelerator ATC-3 has been designed for use with anhydride-epoxy resin systems although it is also suitable for promoting acid-epoxy reactions.


Specificity of AFC Accelerator AMC-3

AFC Accelerator ATC-3 will promote gelation and eventual cure of anhydride- epoxy resins at room temperature. The rate and extent of cure will be dependent on the rheology of the system and ultimate physical properties will develop slowly below the glass transition temperature. Room temperature cure with AFC Accelerator ATC-3 may often be adequate in molding, potting, encapsulation, sealing, adhesive and coating applications where ultimate initial physical properties are not paramount. Subsequent heating in service will lead to development of the properties inherent to the system employed.

At elevated temperatures, AFC Accelerator ATC-3 gives three to four times the rate of reaction of common promoters such as tertiary amines. This allows a significant reduction in the time and/or temperature required for gelation and cure. Processing cycles can therefore be modified to increase throughput and reduce energy requirements.

Raw material savings can also be realized with AFC Accelerator ATC-3. At high processing temperatures, anhydrides are caused to react to a greater extent before loss through volatilization. Alternatively, the processing temperature can be reduced to lessen or eliminate anhydride volatilization.

It is well known that incorporating dimer, trimer and other polybasic acids into epoxy resins imparts flexibility and toughness. AFC Accelerator ATC-3 is particularly useful in such formulations because it effects essentially complete addition of the carboxylic acid groups to the epoxide groups before any etherification or homopolymerization reactions take place. This allows the preparation of stable, acid terminated adducts or oligomers from a dibasic acid and a diepoxide; the resulting products can be cured by addition of further epoxy resin or an anhydride-epoxy mixture. Thermosetting formulations can be prepared by using a slight excess of epoxy resin with a dibasic acid or by use of acids or epoxides with functionally greater than two. The rates of reaction in all of these cases will be fast as indicated for AFC Accelerator ATC-3 in anhydride-epoxy systems.

In general, AFC Accelerator ATC-3 will be found useful in all applications where there is a need for faster or lower temperature cure with anhydride-epoxy or acid-epoxy resin systems. It has been found to be effective with all commonly used anhydrides and epoxy resins, including cycloaliphatic as well as glycidyl ether types. Suggested areas of application include potting, encapsulation, molding, filament windings, laminates and structural composites, adhesives, sealants and coatings.

Contact Us

For more information on AFC Accelerator ATC-3™ or any of our Accelerators, please contact AMPAC Fine Chemicals:
Tel +1 916 353 3555
Fax +1 916 353 3505
Email accelerators@apfc.com