Using dynamic mechanical analysis to characterize the cure of phenolic resins

This research has primarily focused upon using dynamic mechanical analysis (DMA) as a technique for characterizing the curing progression of aqueous phenol formaldehyde (PF) resins. These resins are utilized by the forest products industry to produce a wide variety of structural flakeboard and other composite panels.; The technique is based upon a measurement of the area under the tan delta curve when a partially precured PF resin specimen is isothermally heated in the DMA. The DMA scan is sensitive to a series of rheological events which lead to the full cure or vitrification stage of the sample. The magnitude of tan delta area has been found to be directly proportional to the time required to completely vitrify the partially precured resin sample.; This technique has been successfully applied to quantitatively describe the curing behavior of PF resins under a variety of chemical and environmental conditions.