Monitoring the Cure of a Composite Matrix Resin with Microdielectrometry.
Abstract
Solvent free resin was prepared from a MY720-DDS prepreg solution by evaporation in a vacuum oven. This material was cured under vacuum by a ramp-hold-ramp to cure temperature cycle and the temperature and dielectric loss factor at 5 frequencies were measured every four minutes for the duration of the cure cycle. At selected times during the cure, small samples of the reacting mixture are removed and quenched and subsequently analyzed for Tg. At frequencies of 1 and 10 Hz, the ionic conductivity dominates the loss factor and the logarithmic derivative of the loss factor with respect to time equals the logarithmic derivative of the conductivity with respect to time. This derivative is then related to the derivative of Tg with respect to time by a WLF equation. Keywords: Conductivity, Thermosetting polymers, Williams-Landel-Ferry equation, Glass transition temperature, Epoxy resins, Amine hardener, Network structure, Microdielectrometry, Differential scanning calorimetry, Loss factor.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 15, 1986
- Accession Number
- ADA177490
Entities
People
- Stephen D. Senturia
- Wayne W. Bidstrup
Organizations
- Massachusetts Institute of Technology