Mechanical Properties And Antibacterial Properties Of Inorganic Nanoparticles/Polymer Composite Nanofibers

Due to the high porosity and surface to mass ratio,electrospun nanofibers have potential applications in the field of biomedical,environmental,personal protection and electronic engineering.Tissue engineering materials and wound dressings are the most important research.The performance of nanofiber membranes are not sufficient?In this paper,the following studies are carried out on the optimization of mechanical and antibacterial properties.Firstly,through ring-opening multibranching polymerization of glycidol,ND nanoparticles surface can be covered by the hyperbranched polyglycerol?PG?.ND-PGs were suspended in aqueous solution of PVA to generate composite nanofibers by the electrospinning technique.FITR and differential scanning calorimetry?DSC?results revealed the enhanced filler–PVA interactions following PG functionalization.The improved dispersivity of PG-functionalized NDs?ND-PGs?in water and PVA matrix was verified by sedimentation tests and TEM,respectively.The grafting of PG on ND surface increased the tensile strength up to 60%,Young's modulus up to 51%,and toughness up to 59%,for 3 wt% ND/PVA composite nanofiber membranes.Therefore,the enhanced mechanical performance of ND-PG/PVA nanocomposites can be attributed to the enriched hydroxyl groups of PG which improved the dispersion of nanofillers within composite matrix and strengthened filler–matrix interactions.Therefore,functionalization of nanofillers with hyperbranched polyglycerol could be a promising strategy for mechanical enhancement of filler/polymer composite nanofibers.This method is also applicable for enhancement of mechanical properties of the hydrophilic polymer nanofibers by other nanoparticles containing-OH and –COOH.Secondly,we chose CS/GE as the polymer matrix due to its excellent biocompatibility and biodegradability.Fe₃O₄ nanoparticles?NPs?were utilized to improve the mechanical and antibacterial properties of chitosan?CS?/gelatin?GE?composite nanofiber membranes.SEM,DSC and TGA indicated Fe₃O₄ nanoparticles could improve the diameter of nanofiber and the stability of matrix.FTIR and XRDinduced the interaction between Fe₃O₄ and CS/GE matrix through hydrogen bonding.The incorporation of Fe₃O₄ NPs resulted in a substantial enhancement of mechanical properties.The optimum mechanical performance was demonstrated on 1 wt%Fe₃O₄/CS/GE nanofiber membranes,achieving 128% increase of tensile strength,155% augment of Young's modulus,and 100% boost of toughness from CS/GE.The excellent mechanical enhancement can be explained by the effective dispersion of fillers and the filler-matrix interactions.Moreover,zones of inhibition for Escherichia coli and Staphylococcus aureus expanded markedly with the supplement of Fe₃O₄ NPs.In all,nanofiber membranes made of Fe₃O₄/CS/GE composite with tailored mechanical and antibacterial properties appear a promising wound dressing material.Finally,the aim of this work is to enhance and maintain the antibacterial properties with appropriate mechanical properties.We studied the drug loading nanofibers with core-shell structure by PLA and drug loading HNTs as core and PVA/CS as shell.SEM shows the incorporation of HNTs does not affect the structure of nanofiber.FTIR and DSC suggested the existence of interaction between HNTs and matrix.The incorporation of HNTs resulted in an enhancement of mechanical properties of core-shell nanofiber.Importantly,from the drug release curve,the drug loading HNTs with core-shell nanofibers are able to release the antibacterial drug TCH in a sustained manner for 10 days,more effective than the TCH-HNT and TCH-polymer without HNT.Moreover,zones of inhibition for Escherichia coli and Staphylococcus aureus could maintain for 9 days,due to the sustained release of TCH.Combining drug loading particle and core-shell structure could enhance and maintain the antibacterial properties with appropriate mechanical properties.