| Popis: |
Polyvinyl alcohol (PVA) decompose before melting, making it difficult for melt processing. This phenomenon limits the applications of PVA. Therefore, to widen the application of PVA, in the present work, the PVA films have been prepared by the flow casting method. And talc added as an inorganic nucleating agent to improve the crystallinity of PVA. The effects of talc on the crystallization behavior of PVA are tested by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and successive self-nucleation annealing (SSA). The crystallization kinetics behavior of talc was is further studied by Mo Zhishen equation and Avrami equation. The results show that the addition of talc to the PVA film promotes its crystallization, and as the content of the nucleating agent increases, the crystallinity tends to increase, and the thickness of the wafer becomes uniform due to the increase of nucleation points. These results show that talc regulates the crystallization of PVA, improves the crystallinity and crystallization rate of PVA, and has a heterogeneous nucleation effect. PVA itself exhibits hydrophilicity because it contains large number of hydroxyl groups, and has good physical and chemical properties. In addition, the mechanical properties and water resistance have been further improved by improving the crystallinity of PVA, and the practicability of PVA film in actual production was improved. |
