Mechanisms 4,4 -diaminodiphenyl

The conversion of a hydrazobenzene into a diaminodiphenyl upon treatment with acid is termed the benzidine rearrangement. The following mechanism for the formation of benzidine from hydrazobenzene appears reasonable ... 

Mechanism and Kinetics of the Cure Process in Tetraglycidyl-methane Dianiline-Diaminodiphenyl Sulphone Thermoset System... 

Morgan, R. J., Mones, E. T. The Cure Reactions, Network Structure and Mechanical Response of Diami nodiphenyl Sulfone Cured Tetraglycidyl 4,4 Diaminodiphenyl Methane Epoxies, Polymer (submitted)... 

Compounds such as aniline, aminophenol, and other compounds generated from the diaminodiphenyl ether moiety are common in the pyrolysate of all polymers. The presence of specific fragments allows the polymer identification and the structure of the cycles determines the decomposition mechanism of each polymer [15]. 

Most of the commerically available high-performance moulding materials use epoxidized cresol-novolak/novolak (especially phenolic novolak) as a base. Systems with amine curing agents, for instance 4,4 -diaminodiphenyl-sulfone (2) or 4,4 -diaminodiphenylmethane, do provide high-quality moulding substances with a thermo-mechanical performance comparable to our system. They are, however even less stable under storage. 

In the early works, it was found that the pulse method could lead to the fastest heating of epoxy resins [98] and improve their mechanical properties [99]. For example, it was shown that a computer controlled pulsed microwave processing of epoxy systems that consisted of diglycidyl ether of bisphenol A (DER 332) and 4,4 -diaminodiphenyl sulfone (DOS) in a cavity operated in TM012 mode could be successfully applied to eliminate the exothermic temperature peak and maintain the same cure temperature at the end of the reaction [100]. The epoxy systems under pulsed microwave irradiation were cured faster, and it was possible to cure them at higher temperatures when compared with a continuous microwave or conventional thermal processing. 

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