Hybrid nanocomposites combining biopolymer fibers incorporated with nanoparticles (NPs) have received increasing attention due to their remarkable characteristics. Inorganic NPs are typically chosen for their properties, such as magnetism and thermal or electrical conductivity, for example. Meanwhile, the biopolymer fiber component is a backbone, and could act as a support structure for the NPs. This shift towards biopolymers over traditional synthetic polymers is motivated by their sustainability, compatibility with biological systems, non-toxic nature, and natural decomposition. This study employed the solution blow spinning (SBS) method to obtain a nanocomposite comprising poly(vinyl pyrrolidone), PVA, and gelatin biodegradable polymer fibers incorporated with magnetic iron oxide nanoparticles coated with poly(acrylic acid), PAA_2k, coded as γ-Fe₂O₃-NPs-PAA_2k. The fiber production process entailed a preliminary investigation to determine suitable solvents, polymer concentrations, and spinning parameters. γ-Fe₂O₃-NPs were synthesized via chemical co-precipitation as maghemite and coated with PAA_2k through the precipitation–redispersion protocol in order to prepare γ-Fe₂O₃-NPs-PAA_2k. Biopolymeric fibers containing coated NPs with sub-micrometer diameters were obtained, with NP concentrations ranging from 1.0 to 1.7% wt. The synthesized NPs underwent characterization via dynamic light scattering, zeta potential analysis, and infrared spectroscopy, while the biopolymer fibers were characterized through scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis. Overall, this study demonstrates the successful implementation of SBS for producing biopolymeric fibers incorporating iron oxide NPs, where the amalgamation of materials demonstrated superior thermal behavior to the plain polymers. The thorough characterization of the NPs and fibers provided valuable insights into their properties, paving the way for their potential applications in various fields such as biomedical engineering, environmental remediation, and functional materials.

Non-stoichiometric hydroxyapatite (HAp) presents an additional phase in its structure due to calcium or phosphorus excess, which can influence the material’s mechanical properties, as well as its bioactivity and biodegradability. While stoichiometric HAp, with calcium to phosphorus ratio (Ca/P) of 1.67, has been widely investigated, only a few studies have reported the synthesis of HAp with higher Ca/P ratio. In this work, non-stoichiometric HAp nanoparticles were synthesized using chemical precipitation method followed by a calcination protocol. In order to achieve better process control with chemical precipitation, starch, a natural additive, was applied. Three types of starch were selected for comparison: nonionic starch (NS), soluble starch (SS), and cationic starch (CS). Infrared spectroscopy and chemical analysis results confirmed the non-stoichiometric profile of the synthesized HAp, with a 1.98 Ca/P ratio. X-ray diffraction (XRD) results showed that HAp and calcium oxide (CaO) crystalline phases were obtained and no residual starch was detected. Rietveld refinements confirmed that, for all three types of starch, the content of crystalline HAp was greater than 96.5% and the unit cell volume was not affected. Scanning electron microscopy (SEM) showed agglomeration of particles. Nanoparticle tracking analysis (NTA) results demonstrated that the use of SS produced the smallest particles (approximately 60nm).

Anais do Simpósio de Engenharia Metalúrgica e de Materiais Sul Fluminense (978-85-5722-634-0) - Síntese De Nanocompósitos Através Da Fiação Por Sopro Em Solução: Fibras Poliméricas Incorporadas Com Nanopartículas