Journal of Polymer Science Part B: Polymer Physics, Vol.33, No.16, 2235-2244, 1995
Miscibility and Cure Kinetics Studies on Blends of Bisphenol-A Polycarbonate and Tetraglycidyl-4,4’-Diaminodiphenylmethane Epoxy Cured with an Amine
Differential scanning calorimetry (DSC) has been applied to characterize the glass transition behavior of the blends formed by bisphenol-A polycarbonate (PC) with a tetrafunctional epoxy (tetraglycidyl-4,4’-diaminodiphenyl methane, TGDDM) cured with 4,4’-diaminodiphenylsulphone (DDS). A rare miscibility in the complete composition range has been demonstrated in these blends. Additionally, the blend morphology was examined using scanning electron microscopy (SEM) and a homogeneous single-phase PC/epoxy network has been observed in the blends of all compositions. Moreover, polycarbonate incorporation has been found to exert a distinct effect on the cure behavior of the epoxy blends. The cure reaction rates for the epoxy-PC blends were significantly higher due to the presence of PC. In addition, the cure mechanism of the epoxy blends was no longer autocatalytic. An n-th order reaction mechanism with n = 1.2 to 1.5 has been observed for the blends of DDS-cured epoxy with PC of various compositions studied using DSC. The proposed n-th order kinetic model has been found to describe well the cure behavior of the epoxy/PC blends up to the vitrification point.
Keywords:TOUGHENING MECHANISMS;FRACTURE-BEHAVIOR;AROMATIC-AMINES;RESINS;DIGLYCIDYLANILINE;POLYETHERIMIDE;SPECTROSCOPY