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 degrees 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 degrees, 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.

Automated summary

Bio-nanocomposite films of sodium alginate/polyvinyl alcohol (SA/PVA) blend with boehmite alumina (BA) nanoparticles were developed in this study. The films exhibited high transparency and eco-friendliness. The BA nanoparticles showed a homogeneous dispersion at low loading but agglomerated at high loading. The addition of 3 wt% BA nanoparticles improved the mechanical properties and hydrophobicity of the films. The films also demonstrated good thermal stability. The novel ternary SA/PVA/BA bio-nanocomposite films have potential applications in biomedical and packaging fields.