Fibrous mats with hydrophobic and oleophilic properties have been fabricated and used as absorbents of oil from stable water in oil emulsions. The mats were prepared by initially mixing two polymers, poly(methyl methacrylate) (PMMA) and polycaprolactone (PCL), in a common solvent. The subsequent electrospinning of the prepared solutions resulted in the production of mechanically stable fiber mats, with enhanced oil absorption capacity and oil absorption selectivity from the emulsions, compared to the pure PMMA or PCL mats. Furthermore, the formed fibrous substrates have been successful in the absorption of oil from different emulsions with a wide range of oil content, from 10 to 80 v%. The performance of the fibrous mats was optimized by the incorporation of hydrophobic silica nanoparticles, reaching oil absorption capacities of 28 g g⁻¹ and negligible water uptake, in the emulsions with 80 v% oil content.

Superhydrophobic and oleophilic polyurethane foams were obtained by spray-coating their surfaces with solutions of thermoplastic polyurethane and hydrophobic silicon oxide nanoparticles. The developed functionalized foams were exploited as reusable oil absorbents from stable water-in-oil emulsions. These foams were able to remove oil efficiently from a wide range of emulsions with oil contents from 10 to 80 v.%, stabilized using Span80. The modified foams could reach oil absorption capacities up to 29 g/g, becoming a suitable candidate for water-in-oil stable emulsions separation.

The excellent catalytic properties of copper nanoparticles (CuNPs) for the degradation of the highly toxic and recalcitrant chlorpyrifos pesticide are widely known. However, CuNPs generally present low stability caused by their high sensitivity to oxidation, which leads to a change of the catalytic response over time. In the current work, the immobilization of CuNPs into a polycaprolactone (PCL) matrix via electrospinning was demonstrated to be a very effective method to retard air and solvent oxidation and to ensure constant catalytic activity in the long term. CuNPs were successfully anchored into PCL electrospun fibers in the form of Cu₂O at different concentrations (from 1.25 wt % to 5 wt % with respect to the PCL), with no signs of loss by leaching out. The PCL mats loaded with 2.5 wt % Cu (PCL-2.5Cu) almost halved the initial concentration of pesticide (40 mg/L) after 96 h. This process was performed in two unprompted and continuous steps that consisted of adsorption, followed by degradation. Interestingly, the degradation process was independent of the light conditions (i.e., not photocatalytic), expanding the application environments (e.g., groundwaters). Moreover, the PCL-2.5Cu composite presents high reusability, retaining the high elimination capability for at least five cycles and eliminating a total of 100 mg/L of chlorpyrifos, without exhibiting any sign of morphological damages.

Investigation of cell wall composition is necessary to understand the interactions between fungi and the environment as it is the external layer exposed to stimuli and detected by other organisms. Pochonia chlamydosporia and Akanthomyces lecanii, two fungal species living in the soil and infecting nematodes and insects, exhibit endophytic interactions with various plant species. Determination of cell wall composition is essential to understand the mechanisms underlying these interactions. Therefore, in this study, for the first time, we assessed the relative amounts of chitin and chitosan in the cell walls of P. chlamydosporia (PC123) and A. lecanii (69NZ, 85SCT, 126KNY, and 447SAF) via Raman spectroscopy. The isolate with the highest chitosan percentage was 69NZ, followed by 85SCT, PC123, 447SAF, and 126KNY. Moreover, combination with conventional approaches for chitin and chitosan quantification yielded quantitative results for all cell wall components. Overall, these results highlight the mechanisms by which fungi exhibit chitosan resistance and avoid detection by the host plant during root colonization.

A new and straightforward route to produce polymeric hollow microfibers has been proposed, for the first time, using a gas dissolution foaming approach.

Nanocellular polymers (i.e., cellular polymers with cells and walls in the nanometric range) were first produced in the early 2000s, with the works of