Aromatic Hardener

Another aromatic diamine hardener of which the glycidylamine has created interest is 4,4-diaminoxliphenyl suphone. The strength/temperature relationship of this epoxies cured with diaminodiphenyl sulphone, and also with two anhydrides.

Diaminodiphenyl sulphone has also been reacted with a limited amount of epichlorohydrin to give compounds that contain both amino hydrogen and epoxide groups. This is specially interesting because the compounds, whilst stable at room temperature, are self curing at elevated temperatures; they also have heat deflection temperature up to 300oC. One would expect such products to form a useful basis for one package adhesives.

It is only natural to be found to expect that mixture of glycidylamine and glycidyl resin ponding interest is the epoxydation of both the amino and hydroxyl groups in amino phenol. The hardeners used for glycidylamine adhesive can be either anhydrides or amines, but since these epoxy adhesives have their greatest value as high hot strength adhesives, there would not appear to be much ease for using aliphatic amines. A patent refering to glycidyl tertiary amines mentions that hardening can be effected by isocyanates and aldhehydes.

It is interesting, but not surprising, to see that a glycidyl tertiary amine can be used to catalyst the anhydride-curing of a glycidyl ether adhesive. On the whole, there is little detailed information on the adhesive properties of the glycidyl amine resins, but interest in the epoxides is increasing.