Analysis of epoxy resin curing kinetics using the Avrami theory of phase change

To przoduce efficiently high quality structural parts from fiber-reinforced epoxy materials systems, it is necessary to develop detailed process models. One key component in any such model involves the prediction of the cure kinetics, which in turn governs the viscosity, resin flow, void formation, and other important processing parameters. In this study, a series of isothermal and dynamic differential scanning calorimetry experiments was performed using Hercules 3501-6 and 3502 resins (TGDDM epoxy with DDS curing agent). The hypothesis of a dispersion of growing microgel particles, which become a continuous-phase solid at the gel point, was used as a basis to apply the Avrami theory of phase change to describe the polymerization kinetics up to the gel point. The extended equations for nonisothermal conditions properly accounted for the temperature effects on the kinetics. Comparison of the theoretical predictions with experimental data suggests that the Avrami theory of phase change may model adequately the cure kinetics of these systems, at least up to the gel point.

[1]  L. Nielsen,et al.  Characterization of Network Structure of Epoxy Resins by Dynamic Mechanical and Liquid Swelling Tests , 1969 .

[2]  L. Nicolais,et al.  Thermokinetics and chemorheology of the cure reactions of the tetraglycidyl diamino diphenyl methane–diamino diphenyl sulfone epoxy systems , 1984 .

[3]  R. Bruce Prime,et al.  Differential scanning calorimetry of the epoxy cure reaction , 1973 .

[4]  M. Avrami.  Kinetics of Phase Change. I General Theory , 1939 .

[5]  R. Cuthrell.  Epoxy polymers. II. Macrostructure , 1968 .

[6]  E. Sacher,et al.  Kinetics of epoxy cure: (1) The system bisphenol-A diglycidyl ether/m-phenylene diamine , 1971 .

[7]  Farrington Daniels,et al.  The Application of Differential Thermal Analysis to the Study of Reaction Kinetics1 , 1957 .

[8]  James L. Racich,et al.  Nodular structure in epoxy resins , 1976 .

[9]  T. Amano,et al.  Some aspects of nonisothermal crystallization of polymers. II. Consideration of the isokinetic condition , 1973 .

[10]  C. Browning.  Composite Materials: Quality Assurance and Processing , 1983 .

[11]  E. G. Bobalek,et al.  Some implications of the gel point concept to the chemistry of alkyd resins , 1964 .

[12]  Musa R. Kamal,et al.  Kinetics and thermal characterization of thermoset cure , 1973 .

[13]  J. Kardos.  PROPERTY CONTROL IN REINFORCED PLASTICS THROUGH INTERFACE TAILORING , 1973 .

[14]  R. Fava,et al.  Differential scanning calorimetry of epoxy resins , 1968 .

[15]  P. Flory.  Principles of polymer chemistry , 1953 .

[16]  E. Sacher,et al.  Kinetics of epoxy cure: 2. The system bisphenol-A diglycidyl ether/polyamide , 1972 .

[17]  M. Avrami.  Kinetics of Phase Change. II Transformation‐Time Relations for Random Distribution of Nuclei , 1940 .

[18]  Takeo Watanabe,et al.  Some aspects of nonisothermal crystallization of polymers. I. Relationship between crystallization temperature, crystallinity, and cooling conditions , 1972 .

[19]  D. Coulter,et al.  The mechanism of cure of tetraglycidyl diaminodiphenyl methane with diaminodiphenyl sulfone , 1983 .

[20]  Lester M. Cohen.  The Effects Of Epoxy Shrinkage On The Advanced X-Ray Astrophysics Facility Technology Mirror Assembly , 1984, Other Conferences.

[21]  R. B. Prime,et al.  Dynamic Cure Analysis of Thermosetting Polymers , 1970 .

[22]  Jinhwan Kim,et al.  Cure kinetics of epoxy formulations of the type used in advanced composites , 1984 .