Non-isothermal crystallization of NaX nanocrystals/poly (vinyl alcohol) nanocomposite

Abstract

This paper reports the successful synthesis of NaX nanocrystals using an organic, additive-free hydrothermal approach. Then, solution casting was used to fabricate nanocomposites of poly (vinyl alcohol) (PVA) and NaX nanocrystals. The structure and morphology of the nanozeolite and nanocomposite were determined by XRD, FE-SEM, and EDX analyses. The non-isothermal crystallization kinetic of the neat PVA and its nanocomposite consisting NaX nanocrystals have been investigated by differential scanning calorimetry (DSC). Judging from the crystallization kinetics based on the DSC data, it was demonstrated that NaX nanocrystals can play a role in an effective nucleating agent in the crystallization of PVA. It has been demonstrated that crystallinity degree of the nanocomposite had been enhanced by increasing the content of NaX nanocrystals up to 1 mass%. Using the Friedman isoconversional method, it was shown that the value of effective energy barrier for PVA/NaX nanocrystals (1 mass%) system is smaller than the neat PVA.