PHB/PCL fibrous membranes modified with SiO2@TiO2-based core@shell composite nanoparticles for hydrophobic and antibacterial applications

In order to prepare multifunctional fibrous membranes with hydrophobicity, antibacterial properties and UV resistance, we used silica and titanium dioxide for preparing SiO₂@TiO₂ nanoparticles (SiO₂@TiO₂ NPs) to create roughness on the fibrous membranes surfaces. The introduction of TiO₂ was used for improving UV resistance. N-Halamine precursor and silane precursor were introduced to modify SiO₂@TiO₂ NPs to synthesize SiO₂@TiO₂-based core@shell composite nanoparticles. The hydrophobic antibacterial fibrous membranes were prepared by a dip-pad process of electrospun biodegradable polyhydroxybutyrate/poly-ε-caprolactone (PHB/PCL) with the synthesized SiO₂@TiO₂-based core@shell composite nanoparticles. TEM, SEM and FT-IR were used to characterize the synthesized SiO₂@TiO₂-based core@shell composite nanoparticles and the hydrophobic antibacterial fibrous membranes. The fibrous membranes not only showed excellent hydrophobicity with an average water contact angle of 144° ± 1°, but also appreciable air permeability. The chlorinated fibrous membranes could inactivate all S. aureus and E. coli O157:H7 after 5 min and 60 min of contact, respectively. In addition, the chlorinated fibrous membranes exhibited outstanding cell compatibility with 102.1% of cell viability. Therefore, the prepared hydrophobic antibacterial degradable fibrous membranes may have great potential application for packaging materials.

Schematic illustration of the synthesis of SiO₂@TiO₂-based core@shell composite nanoparticles (top) and antibacterial hydrophobic behavior of fibrous membranes (bottom).