Glen David Merfeld

Phase behavior and morphology of poly(phenylene ether)/epoxy blends

Abstract The miscibility of diglycidyl ether of bisphenol-A (DGEBA) based epoxies with a series of poly(2,6-dimethyl-1,4-phenylene ether) (PPE) resins was measured and the effects of PPE molecular weight, end-capped or grafted functionality, and blend composition were explored. Interpretation of phase behavior was aided by the use of the Flory–Huggins theory. Miscibility behavior in the unreacted blends was found to correlate with trends in phase separation during the curing reaction. The cured morphologies of these blend systems were also studied. The compatibilization effect of PPE-epoxy copolymer formation was found to play a dominant role in determining the final size of the dispersed phase, while temperature control of reaction and mass transfer kinetics were identified as a possible means of further affecting the cured morphology.

Development of low temperature curing, 120°C, durable, corrosion protection powder coatings for temperature sensitive substrates

Commercial low temperature cure powder coatings, including candidates representative of all the major coating chemistries, were evaluated. Nearly all failed to adequately react at a cure schedule of 120°C for 30 min, and none, even when prepared at their manufacturer’s lowest recommended cure conditions, met the stringent performance needs for temperature-sensitive military applications. Initial research is presented toward developing low temperature cure powder coatings that simultaneously meet all performance requirements at this target cure schedule. Using commercial resins, corrosion inhibitors, and catalysts, this research effort has closed gaps in low temperature cure coating performance and has helped to identify critical deficiencies. This study establishes direction for future developments in new resin and catalyst technologies.