Premium
Kinetic study of polymerization/curing of filament‐wound composite epoxy resin sytems with aromatic diamines
Author(s) -
Golub M. A.,
Lerner N. R.,
Hsu M. S.
Publication year - 1986
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.1986.070320536
Subject(s) - diglycidyl ether , epoxy , curing (chemistry) , differential scanning calorimetry , polymerization , materials science , polymer chemistry , glass transition , activation energy , bisphenol a , polymer , composite material , chemistry , thermodynamics , physics
The kinetics of the polymerization/curing of an 80/20 blend of a diglycidyl ether of bisphenol A (DGEBA) and a diglycidyl ether of 1,4‐butanediol (DGEBD) with a commercial mixture of methylene dianiline and m ‐phenylene diamine (Tonox 60/40) was studied, at amine/epoxy ratios ranging from 1.1 to 4.4. Fourier transform infrared (FT‐IR) measurements were used to follow the extent of epoxy conversion at 18–122°C, and bulk viscosity measurements were used to define the working range of the resin. For an amine/epoxy ratio of 1.1, the activation energy for the polymerization/curing reaction (based on time to 50% epoxy conversion in the S‐shaped conversion‐time plots) was 11.9 kcal/mole by FT‐IR. This value compared favorably with the corresponding value of 12.7 kcal/mole obtained by Moroni and co‐workers in a complementary differential scanning calorimetry (DSC) study of the same system. The FT‐IR conversion‐time plots were fitted to a kinetic expression that can be accommodated by an autocatalytic mechanism; the expression contains two rate constants with activation energies of 13.7 and 10.0 kcal/mole, respectively. The viscosity of the curing epoxy resin was found to obey the Williams‐Landel‐Ferry equation, with a Di Benedetto expression for the glass transition temperature.