Plasticization of poly(arylene ether nitrile) by the melt blending of phthalonitrile prepolymer: A rheological, mechanical, and thermal study

Abstract

AbstractPoly(arylene ether nitrile) (PEN)/phthalonitrile prepolymer (PNP) blends were prepared via a melt‐mixing process. The melt flow properties, compatibility, and thermal and mechanical properties were characterized by dynamic rheological testing, dynamic mechanical analysis, tensile testing, thermal analysis, and fracture surface morphology observation. The melt‐mixed PEN/PNP blends displayed excellent melt flow properties during processing. When the PNP content in PEN was increased, the viscosity of the blends decreased considerably. Compared with that of pure PEN, the dynamic complex viscosity of the PEN/PNP blend with an 11% addition of PNP dropped sharply from 7000 to 2000 Pa s at 350°C and a frequency of 10 Hz. The dynamic mechanical analysis and differential scanning calorimetry results showed good compatibility between PEN and PNP. Observations of the morphology of the fractured surfaces revealed better component dispersion in which PNP was dissolved in the PEN matrix. Importantly for further commercial applications, the blending materials maintained the characteristic thermal and thermooxidative stability and mechanical properties of PEN. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010