Sea‐island polyurethane/polycarbonate composite nanofiber fabricated through electrospinning

Abstract

Sea-island polyurethane (PU)/polycarbonate (PC) composite nanofibers were obtained through electrospinning of partially miscible PU and PC in 3 : 7 (v/v) N,N-dimethylformamide (DMF) and tetrahydrofuran (THF) mixture solvent. Their structures, mechanical, and thermal properties were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric (TG), and differential scanning calorimetry (DSC). The structures and morphologies of the nanofibers were influenced by composition ratio in the binary mixtures. The pure PC nanofiber was brittle and easy to break. With increasing the PU content in the PU/PC composite nanofibers, PU component not only facilitated the electrospinning of PC but improved the mechanical properties of PU/PC nanofibrous mats. In a series of nanofibrous mats with varied PU/PC composition ratios, PU/PC 70/30 showed excellent tensile strength of 9.60 Mpa and Young's modulus of 55 Mpa. After selective removal of PC component in PU/PC composite nanofibers by washing with acetone, the residual PU maintained fiber morphology. However, the residual PU nanofiber became irregular and contained elongated indents and ridges along the fiber surface. PU/PC composite fibers showed sea-island nanofiber structure due to phase separation in the spinning solution and in the course of electrospinning. At PC content below 30%, the PC domains were small and evenly dispersed in the composite nanofibers. As PC content was over 50%, the PC phases became large elongated aggregates dispersed in the composite nanofibers.

Centrifugal Spinning: An Alternative Approach to Fabricate Nanofibers at High Speed and Low Cost

“…However, the material choices for other nanofiber production methods, including melt blowing, 7 bicomponent fiber spinning, 8,9 phase separation, 10 template synthesis, [11][12][13][14] and self-assembly, [15][16][17][18] Downloaded by [Laurentian University] at 07:31 25 November 2014 are limited. For example, melt blowing, a highly productive route, has been used widely in industry for producing fibers with diameters greater than 1 μm.…”

“…8,9 In order to produce nanofibers, at least one of the components has a nanosized cross-section. Commonly-seen cross-sectional shapes of bicomponent fibers are islands-in-the-sea, segmented pie, and hollow segmented pie.…”

“…Although electrospinning is popular in academic research, the wide-spread industrial use of electrospinning is limited mainly due to its low production rate. 5,6 Other nanofiber production methods have also been reported, such as melt blowing, 7 bicomponent fiber spinning, 8,9 phase separation, 10 template synthesis, [11][12][13][14] and self-assembly. [15][16][17][18] However, the material choices for these complex methods are limited, which hinders their practical applications.…”

Formation of bead‐free and core–shell superfine electrospinning fibers under the assistance of another polymer and an interfacial compatibilizer

“…Moreover, electrospinning of polymer blend could combine the advantages of polymer components to improve properties of the final fiber mats. For instance, after adding 30% polycarbonate (PC), Young's modulus of as‐electrospun blend fibers increased to 55 MPa which is almost four times higher than that of pure PU fibers .…”

Measurement of Nanofilament-fabric Optical Properties

“…Liu et al [7] examined sea-island PU/PC composite nanofibers by electrospinning, and Kamiyama et al [8] produced the world's first 700 nm ultra-fine polyester using improved sea-island composite-spinning technology. Li and Joo [9] studied nanofiber nonwovens composed of PET/co-PET sea-island bicomponent fibers by an alkali treatment.…”