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Novel bio-based and biodegradable electrospun membranes, containing bactericidal ricinoleic acid (RA) units either by copolymerization with butylene succinate (BS) units or by blending PRA and PBS homopolymers, are characterized in their chemical, thermal, mechanical and surface properties. In the blends E. coli and S. aureus mortality rate increases with PRA amount, while the copolymer shows lower bactericidal activity compared to the blend with similar composition. XPS demonstrates that in the blends an enrichment of RA units at the fiber surface occurs during electrospinning due to phase separation, while in the copolymer RA units are homogeneously dispersed along fiber cross-section. [ABSTRACT FROM AUTHOR]

• Poly(l -lactic acid) electrospun fibers loaded with struvite crystals were prepared. • PLLA fibers loaded with struvite can recover nutrients (N and P) from solution. • Struvite dispersion and location along the fiber section affect nutrient recovery. • The biodegradable nanostructured mat can be employed as ready-to-use fertilizer. One of the greatest global challenges of the 21st century is facing the depletion of phosphorous reserves, widely used in fertilizers. One possibility is to recover the phosphorous discharged in the water by human activities, with the consequent additional benefit of improving water quality by limiting eutrophication. In this work, biodegradable poly(l -lactic acid) (PLLA) nonwovens produced by electrospinning are proposed as highly porous fibrous materials characterized by high surface-to-volume ratio for promoting the crystallization of struvite crystals as a means to recover both phosphorus and nitrogen from a nutrient rich solution. To this aim, PLLA fibers were intentionally loaded with a small amount of struvite crystals (3,7 wt%) by applying different preparation procedures, including sonication steps, single-nozzle and coaxial electrospinning. PLLA fibers containing struvite crystals were immersed in a synthetic solution of suitable ions to investigate the occurrence of struvite accumulation through the analysis of the soaked nonwovens with several techniques, i.e. Scanning and Transmission Electron Microscopy, Wide Angle X-Ray Diffraction, Thermogravimetric analysis and Atomic Emission Spectrometry. We demonstrated that struvite loaded in the PLLA fibers successfully acted as crystal seeds and enabled the precipitation of struvite crystals firmly attached to fiber surface. Results showed that the quality of crystal seeds dispersion in PLLA fibers as well as their location along the fiber section heavily affect struvite recovery. Prospectively, these materials can be directly used, after being in contact with wastewater and enriched with struvite, as ready-to-use fertilizers. [ABSTRACT FROM AUTHOR]