RHEOLOGICAL PROPERTIES OF PHENOPHTHALEIN POLY(ETHER ETHER KETONE)

The rheological properties of the novel engineering thermoplastic phen ophthalein poly(ether ether ketone) (PEK-C) have been investigated usi ng both a rotational and a capillary rheometer. The dependence of the viscosity on the shear rate and temperature was obtained. The activati on energy was evaluated both from the Arrhenius and the Williams-Lande l-Ferry (WLF) equation. An estimate for the proper E(eta) (dependent o nly on the chemical structure of the polymer) has been found from the WLF equation at temperatures about T-g + 200 degrees C. Measurements o f the die swell have been performed. The first normal stress differenc es were evaluated from the die swell results and compared with the val ues obtained from the rotational rheometer at low shear rates.