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A novel semi-crystalline polyhydroxyether, poly(hydroxyether ketone) (PHEK), was synthesized via the direct polycondensation between 4,4-dihydroxybenzophenone and epichlorohydrin. By means of Fourier transform infrared and NMR spectroscopy and gel permeation chromatography (GPC), the structure of PHEK was characterized. Differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXRD) show that PHEK is a semi-crystalline polymer with a high rate of crystallization. The polymer possesses a glass transition temperature of 109 • C and a melting temperature of 239 • C. When 4,4 -isopropylidenediphenol was used as a second bisphenol and was added to copolymerize with a stoichiometric amount of epichlorohydin, a series of polyhydroxyether copolymers were obtained. The copolymers with various compositions were characterized by means of NMR, GPC, WAXRD and DSC. It was found that the crystallinity of the copolymers dramatically decreased with increasing content of 4,4 -isopropylidenediphenol. The glass transition temperatures of the copolymers are intermediate between those of PHEK and the poly(hydroxyether of bisphenol A) and decreased with increasing content of 4,4 -isopropylidenediphenol.

The miscibility and specific intermolecular interactions in the blends of poly(hydroxyether ketone) (PHEK) and poly(4-vinylpyridine) (P4VP) were investigated by means of differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The PHEK/P4VP blends displayed single, composition-dependent glass transition temperatures (T g 's), indicating that the blends are miscible in the amorphous state. The miscibility was further confirmed by the equilibrium melting point depression of PHEK in the blends. The FTIR spectroscopy indicates that there were intermolecular specific interactions between PHEK and P4VP, involving intermolecular (and/or intramolecular) hydrogen bonding interactions including OH . . . . O C< and OH . . . . OH of PHEK, and OH of PHEK vs. pyridine rings of P4VP. The strength of these interactions was examined in terms of the determinations of several equilibrium constants according to the Coleman and Painter model. It indicated that the strength of the hydrogen bonding interactions was in the order from weak to strong: OH . . . O C< and OH . . . OH of PHEK and OH of PHEK vs. pyridine rings.