Obtenção de nanofibras por eletrofiação de biopolímeros para liberação modificada de nutrientes

Abstract

The present work aimed to develop electrospun nanofibers based on NPK with the polymers Ecovio®, polyvinyl alcohol (PVA) and cationic starch, aiming at the production of a material with modified release of nutrients. The material obtained was of the Ecovio/(PVA/Starch)/Ecovio sandwich type. The fibers were obtained by electrospinning, and characterized by various physical, chemical and mechanical techniques. The incorporation of NPK significantly increased the conductivity of the solutions (from 0.628 mScm-1 to 9.66 mScm-1 in PVA/Starch), favoring electroreliability. The fibers with nutrients (F1) had a lower amount of beads and an average diameter of 503.86 ± 8.4 nm, compared to 516.45 ± 15.04 nm of the reference (R1). The mechanical analysis showed an increase in the breaking stress (0.71 MPa vs. 0.36 MPa), elongation (41.02% vs. 30.8%) and Young's modulus (6.06 MPa vs. 2.02 MPa). The conductivity of the water indicated rapid release of nutrients, with a peak of 16.19 μScm-1 in 24 hours. TOC analysis revealed release of up to 5.43 mgL-1 of organic carbon and 1.47 mgL-1 of nitrogen in 28 days. The lettuce seed germination assay demonstrated similar performance to the conventional method, indicating potential for agricultural application. Despite the promising results, improvements in the hydrophobicity of the material are necessary to prolong the release of nutrients.