Polyurethane-based nanofibrous structures can be used as adsorbents for arsenic in water. Their adsorption capacity can be significantly increased by doping the structure with ferrous sulphate.

This paper presents an attempt to improve the properties of poly(3-hydroxybutyrate) (P3HB) using linear aliphatic polyurethane (PU400) and organomodified montmorillonite (MMT)—(Cloisite®30B). The nanostructure of hybrid nanobiocomposites produced by extrusion was analyzed by X-ray diffraction and transmission electron microscopy, and the morphology was analyzed by scanning electron microscopy. In addition, selected mechanical properties and thermal properties were studied by thermogravimetric analysis, TGA, and differential scanning calorimetry, DSC. The interactions of the composite ingredients were indicated by FT IR spectroscopy. The effect of the amount of nanofiller on the properties of prepared hybrid nanobiocomposites was noted. Moreover, the non-equilibrium and equilibrium thermal parameters of nanobiocomposites were established based on their thermal history. Based on equilibrium parameters (i.e., the heat of fusion for the fully crystalline materials and the change in the heat capacity at the glass transition temperature for the fully amorphous nanobiocomposites), the degree of crystallinity and the mobile and rigid amorphous fractions were estimated. The addition of Cloisite®30B and aliphatic polyurethane to the P3HB matrix caused a decrease in the degree of crystallinity in reference to the unfilled P3HB. Simultaneously, an increase in the amorphous phase contents was noted. A rigid amorphous fraction was also denoted. Thermogravimetric analysis of the nanocomposites was also carried out and showed that the thermal stability of all nanocomposites was higher than that of the unfilled P3HB. An additional 1% mass of nanofiller increased the degradation temperature of the nanocomposites by about 30 °C in reference to the unfilled P3HB. Moreover, it was found that obtained hybrid nanobiocomposites containing 10 wt.% of aliphatic polyurethane (PU400) and the smallest amount of nanofiller (1 wt.% of Cloisite®30B) showed the best mechanical properties. We observed a desirable decrease in hardness of 15%, an increase in the relative strain at break of 60% and in the impact strength of 15% of the newly prepared nanobiocomposites with respect to the unfiled P3HB. The produced hybrid nanobiocomposites combined the best features induced by the plasticizing effect of polyurethane and the formation of P3HB–montmorillonite–polyurethane (P3HB-PU-MMT) adducts, which resulted in the improvement of the thermal and mechanical properties.

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This paper reposts on nanofibers of polymers doped with ferrous sulphate (FeSO4) possibly in combination with quaternary ammonium salt (QAS) prepared by electrospinning. Three types of polymers (polyvinylidene fluoride/PVDF, polylactic acid/PLA and polyurethane/PU) with good electrospinning processability and good mechanical properties of nanofibers were chosen. The prepared nanofibrous membranes were characterised in terms of morphology of the fibres assessed by SEM, and the pore sizes were determined by porometry. The leaching test showed a firm anchoring of the additive in the nanofiber structure. Antimicrobial activity was monitored after 0 h, 4 h and 24 h using Staphylococcus aureus (CCM 4516) and Klebsiella pneumoniae (CCM 4415) strains. Furthermore, aerosol filtration efficycy was dermined and also quality factor of filtration.The membrane prepared from PU doped with FeSO4 showed the best antibacterial efficiency. The porosity and morphology of the nanofibrous membrane effectively contributed to the trapping of microorganisms. This system was also evaluated as the most suitable for the electrospinning process from the effectivity point of view. Spinning ang dopping process of preparation is easily applicatbole to the the industrial conditions of production which is very importatnt aspect of this submitted scientifique work.