Physico‐mechanical properties of poly (vinyl alcohol), poly (vinyl alcohol)/boric acid, and poly (vinyl alcohol) nanocomposites incorporated with amino‐functionalized and pristine halloysite nanotubes films

Abstract

AbstractEco‐friendly poly(vinyl alcohol) (PVA), PVA/boric acid, PVA/halloysite nanotubes (HNTs), and PVA/amino‐functionalized HNTs (APTES‐HNTs) films were fabricated by a solution casting technique. The samples were characterized by fourier transform infrared, X‐ray diffraction, differential scanning calorimetry, scanning electron microscope, and energy‐dispersive spectroscopy. The characterization results proved the chemical and physical interactions between the PVA and different additives. The viscoelastic behavior of the films was evaluated by DMA and creep analysis. The storage modulus, loss factor, and both αα and ββ transitions affected by APTES‐HNTs as a potential filler to form effective cross‐links. APTES‐HNTs existence enhanced creep‐recovery beyond expectations. Tensile and impact strength were measured to understand samples' mechanical stability. PVA/APTES‐HNTs and PVA/boric acid showed more yield behavior after the elastic limit. Furthermore, the subsequent rupture and impact strength were increased significantly compared with neat PVA and PVA/HNTs. The viscoelastic and mechanical behaviors were linked to each other by the area under Tanδ curve and the work of rupture and impact strength, which their linear correlation coefficient is statistically significant at 95% confidence limits. It seems that the presence of APTES‐HNTs provides new cross‐links, which altered (improved) the physico‐mechanical properties of PVA, offering a bionanocomposite suitable for further applications. From the literature, possible explanations are provided for these observations.