This document is a technical bulletin that provides information on how to formulate anhydride-cured epoxy systems. It covers the types of anhydrides that can be used, the ratios of anhydride to epoxy resin, the accelerators that can be used, and the properties of the cured epoxy resin.
This technical bulletin from Dixie Chemical Company explains how to formulate anhydride-cured epoxy systems using their alicyclic anhydrides. It covers epoxy resins, anhydrides, cure chemistry, side reactions, and cure accelerators. The document provides details on specific anhydrides like THPA, HHPA, and NMA, as well as epoxy resins such as D.E.R.™ 330 and EPON™ 826. It also discusses the effects of crosslinking on performance and how to prepare the curing agent/accelerator mixture for optimal results.
The bulletin emphasizes that no single formulation yields optimal properties for all applications, and that factors like curing time, temperature, and accelerator level must be adjusted based on desired performance. It includes information on side reactions, such as homopolymerization, and how to mitigate them. Accelerators like tertiary amines, imidazoles, and quaternary ammonium salts are discussed, along with their effects on color and performance.
Tetrahydrophthalic anhydride (THPA), Hexahydrophthalic anhydride (HHPA), Methyltetrahydrophthalic anhydride (MTHPA), Methylhexahydrophthalic anhydride (MHHPA), Nadic® methyl anhydride (NMA), and formulated blends of these materials.
Bisphenol A epoxy resins with 'n' values between 0.06-0.12 and epoxy equivalent weight of about 178-192.
One mole of anhydride per mole of epoxy.
Mix anhydride and epoxy resin first, then add the accelerator and mix until uniform.