Microwave processing of two-phase systems : composites and polymer blends

The objective of the current paper was to extend the relationships between complex polymer structures and microwave absorptivity that were formulated in the first three papers of this series (1-3). The microwave processing of composite and polymeric blends via a cylindrical resonance wave cavity and a rectangular standing wave applicator is described. These polymeric materials were irradiated in a low power (< 100W) electric field at 2.45 GHz. Graphite-epoxy laminates were processed in both standing and traveling wave applicators. Rapid heating and curing were achieved in both cases. An observation of significance was that, with proper tuning of the traveling wave device (the precursor of a portable repair tool), it proved to be highly effective in processing. Additionally, a compatible blend of poly(methyl methacrylate) and poly(vinylidene fluoride) was heated in an applicator and the rates of temperature rise were demonstrated to depend upon morphology.