Electrospun fibrous mats have a wide range of applications, and characterizing their mechanical behavior is an important task. In addition to the mechanical properties of the individual fibers, other factors can alter the overall mechanical behavior of the mat. In this study, we use computational and experimental methods to investigate the effect of interfiber bonding on the failure and rupture of typical fibrous mats. A non-linear finite element model of a mat is simulated with randomly distributed fibers with different porosities. The percentage of bonding between intersecting fibers is controlled by an auxiliary code. The results reveal that interfiber bonding increases the stiffness of the mat, and the toughness of the mat increases as well. Interestingly, a large percentage of interfiber bonding at a predefined porosity of a mat does not increase the elastic modulus of the mat, nor does it have considerable effects on the failure behavior. Moreover, the effect of interfiber bonding increases with a mat’s porosity. The findings of this study could help tune the mechanical properties of fibrous mats used for different applications.

The interfacial load transfer is of paramount importance to the bulk mechanical properties enhancement in nanotube-reinforced nanocomposites. Recent single-nanotube nanomechanical pull-out studies report quantitative interfacial load transfer characteristics of nanotube-matrix interfaces in close-to-ideal interfacial binding configurations. However, the elucidation of the actual interfacial load transfer in bulk nanotube nanocomposites remains a significant challenge due to the presence of many complex and inevitable nanotubes’ conformational nonidealities, such as nanotube misalignment and aggregation/entanglement. Here we quantitatively investigate the interfacial load transfer in electrospun carbon nanotube poly(methyl methacrylate) (PMMA) nanocomposite microfibers by using in situ Raman micromechanical characterization techniques. The micromechanical measurements capture the critical tensile strain in the composite microfiber that initiates collective interfacial slip. The nanotube alignment inside the microfiber is characterized by using polarized Raman spectroscopy. The equivalent maximum interfacial shear stress in the tested nanotube-PMMA composite microfibers, which takes into account the nanotube alignment, is quantified using shear-lag micromechanics models and is found to be substantially lower than the reported values from single-nanotube pull-out measurements. The reported findings are helpful to better understand the effect of nanotube conformational nonidealities produced from processing on the interfacial stress transfer characteristics and the strengthening efficiency in nanotube-reinforced nanocomposites.

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Electrospun fibrous meshes have a variety of applications such as filtration, drug delivery, energy storage, and engineered tissues due to their high surface area to mass ratio. Therefore, understanding the mechanical properties of these continuously evolving meshes is critical to expand and improve their performance. In this study, the effect of adding Boron Nitride Nanotube (BNNT) to Polymethylmethacrylate (PMMA) composite meshes on the mechanical properties of the polymer is studied. Electrospinning is used to fabricate microfiber meshes of PMMA and BNNT-PMMA. The fabricated meshes are tested experimentally with a uniaxial tensile tester. In addition, a theoretical model is introduced to investigate the effect of the number of fibers and the diameter of fiber inside the mesh on Young’s Modulus and Tensile Strength of the PMMA mesh. By adding 0.5% BNNT to the PMMA, Young’s Modulus and Tensile Strength of the PMMA mesh improved by 62.4% and 9.3%, respectively. Furthermore, simulated results show enhanced mesh properties when increasing the number of fibers and the single fiber diameter inside the mesh. The findings of this study help in understanding the mechanical properties of the nanocomposite electrospun meshes which expands and improves its utilization in different applications.

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