Miscibility and Crystallization Behavior of Poly (Ethylene Terephthalate)/Phosphate Glass Hybrids

Fundamental studies on miscibility and crystallization behavior of poly (ethylene terephthalate) (PET) and inorganic phosphate glass (Pglass) hybrids were conducted. The Flory-Huggins interaction parameter () value of -0.075 for the PET/Pglass hybrids was obtained using the Nishi-Wang equation, demonstrating that the Pglass and PET components were miscible in the melt state. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the phase separation occurred during quenching from the melt. The phase boundaries between PET and Pglass were blurred, which indicated partial compatibility of the components in the solid state. Contact angle measurements indicated the interfacial tension of PET/Pglass hybrids was 1.5mN/m, and the work of adhesion was 78.0mN/m at 28 degrees C. Based on the Hoffman-Lauritzen theory, the nucleation constant (K-g) and fold surface free energy (sigma(e)) of PET/Pglass hybrids were less than those of neat PET.