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Chemoviscosity modeling for thermosetting resins - i
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Hou, T. H. |
| Copyright Year | 1984 |
| Description | A new analytical model for chemoviscosity variation during cure of thermosetting resins was developed. This model is derived by modifying the widely used WLF (Williams-Landel-Ferry) Theory in polymer rheology. Major assumptions involved are that the rate of reaction is diffusion controlled and is linearly inversely proportional to the viscosity of the medium over the entire cure cycle. The resultant first order nonlinear differential equation is solved numerically, and the model predictions compare favorably with experimental data of EPON 828/Agent U obtained on a Rheometrics System 4 Rheometer. The model describes chemoviscosity up to a range of six orders of magnitude under isothermal curing conditions. The extremely non-linear chemoviscosity profile for a dynamic heating cure cycle is predicted as well. The model is also shown to predict changes of glass transition temperature for the thermosetting resin during cure. The physical significance of this prediction is unclear at the present time, however, and further research is required. From the chemoviscosity simulation point of view, the technique of establishing an analytical model as described here is easily applied to any thermosetting resin. The model thus obtained is used in real-time process controls for fabricating composite materials. |
| File Size | 1176732 |
| Page Count | 46 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19850003788 |
| Archival Resource Key | ark:/13960/t8x97203d |
| Language | English |
| Publisher Date | 1984-11-01 |
| Access Restriction | Open |
| Subject Keyword | Composite Materials Viscosity Rheology Reaction Kinetics Curing Polymerization Mathematical Models Thermosetting Resins Autoclaving Diffusion Glass Transition Temperature Real Time Operation Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
