Premium
Epoxy thermosetting systems: Dynamic mechanical analysis of the reactions of aromatic diamines with the diglycidyl ether of bisphenol A
Author(s) -
Babayevsky P. G.,
Gillham J. K.
Publication year - 1973
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.1973.070170709
Subject(s) - diglycidyl ether , thermosetting polymer , glass transition , epoxy , materials science , diamine , polymer chemistry , ether , vitrification , dynamic mechanical analysis , bisphenol a , isothermal process , polymer , composite material , chemistry , organic chemistry , thermodynamics , medicine , physics , andrology
Dynamic mechanical behavior during the reactions of four aromatic diamines ( m ‐phenylenediamine, 4,4′‐diaminodiphenylmethane, 4,4′‐diaminodiphenyl sulfone, and benzidine) with the diglycidyl ether of bisphenol A was studied by torsional braid analysis under isothermal conditions. Depending on the cure temperature, three types of behavior were observed: (I) below T gg (the glass transition temperature of the reactive systems at the gel point); (II) between T gg and T g ∞ (the glass transition temperature of the ultimately cured polymers); (III) above T g ∞ . Overall activation energies and apparent overall rate constants of the cure reactions based on third‐order overall kinetics were determined before gelation, after gelation but before vitrification, and after vitrification, using gelation time, relative rigidity, and glass transition temperature T g ( t ) of the polymers as kinetic terms. The influence of cure temperature and structure of the diamines on the kinetic parameters is discussed.