Effect of boehmite alumina nanoparticles on the physical and chemical characteristics of eco-friendly sodium alginate/polyvinyl alcohol bio-nanocomposite film

In the present work, bio-nanocomposite films of sodium alginate/polyvinyl alcohol (SA/PVA) blend with different loadings of boehmite alumina (BA) nanoparticles were developed via the film-casting technique. The bio-nanocomposite films obtained, containing boehmite alumina nanoparticles, are highly transparent and eco-friendly. The morphological characterization, by using TEM, AFM and SEM, indicate the fact that the BA nanoparticles showed a homogeneous dispersion at low BA loading, with rod-like features and plates with cubic crystal shapes morphology. Conversely, BA agglomeration was observed at higher BA loading. The mechanical properties indicate improvements in the tensile strength and elongation-at-break and flexibility in the 3 wt% BA nanoparticles loading. This (3 wt%) is stable with homogeneous dispersion of BA nanoparticles in the SA/PVA blend matrix, which is confirmed by SEM and TEM analysis. Additionally, the contact angle of the blend matrix was observed to be 34.7° and with the incorporation of boehmite alumina (BA) of between 3 to 9 wt % to the hydrophilic blend matrix, the results in contact angles of the nanocomposite films in increasing hydrophobic order of 47.9–67.9°, respectively. Furthermore, the incorporation of BA nanoparticles shows that the SA/PVA blend matrix have desirable thermal stability. From the present study, the novel ternary SA/PVA/BA bio-nanocomposite films could be a potential candidate to be used in the fields of biomedical (such as wound healing) and packaging applications.