Aminimide as hardener/curing promotor for one part epoxy resin composition

Abstract

SynopsisThree kinds of aminimide compounds were examined as latent hardenedpromotors for epoxy resins. Since aminimides are thermolyzed to generate tertiary amine and isocyanate, the compounds are useful as polymerization initiators for the epoxy group as well as promotors for epoxy-acid anhydride reaction. The pot l i e was over 30 days at 40°C for a formulated one-part epoxy resin system. In comparison with epoxy resins cured with conventional hardeners, several interesting characteristics of the mechanical and electrical properties were observed. In particular, the epoxy resins cured by aminimides exhibited high tensile strength and high impact strength, which make them excellent curing agents for adhesive applications. The reasons for these unique properties are discussed.

Effect of type of substitution in 4,4′‐bis‐(diaminodiphenyl) methane hardener on cure kinetics, mechanical, and flame retardant properties of tetrafunctional epoxy resins

“…An excellent approach toward the development of latency in curing agents has been demonstrated by the use of aminimide compounds 5. The aminimide contains a ylide structure (N − N + ), which is responsible for the latent properties of these compounds, and it is stable at room temperature.…”

Photobase generation from amineimide derivatives and their use for curing an epoxide/thiol system

“…More than three decades ago, reviews suggested that amineimide derivatives can produce tertiary amines and the corresponding isocyanates by pyrolysis 12, 13. Some articles have already proposed to apply amineimide derivatives to epoxide curing systems as thermally latent catalysts or thermally curing agents with the mechanism 14–18. Some reports also have indicated application to photoresists with polarity changes of amineimide moiety by UV irradiation 19, 20.…”

Aminimides derived from p -substituted benzoylformic acid ester as thermal/photolatent bases and photoradical initiators

“…In addition, thermal/photo dual base catalysts are expected to improve the issue that the photocuring cannot take place smoothly if the materials are not transparent enough toward the photoirradiation (so‐called “photo/thermal dual‐cure”) . Aminimides are attractive candidates for the photo/thermal dual base catalysts, because they are reported to undergo the thermal cleavage of the NN bond to produce tertiary amines, which are applicable as thermal latent base catalysts for epoxides, epoxide/acid anhydride system, and epoxide/thiol system, and because some of the aminimide derivatives such as benzimides, aminimides possessing PhCON − N + moieties, undergo photolysis to produce tertiary amines, that can be utilized as photobase catalysts for the epoxide/thiol system …”