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A homogeneous composite nonwoven support (HCNS) for high temperature‐resistant separation membranes is developed by wet‐laid and hot‐pressing technology using undrawn polyethlene terephthalate fibers as bonding fibers. Poly(phthalazine ether sulfone ketone)(PPESK)ultrafiltration (UF) membrane supported by HCNS performs excellent permeability, retention, and long‐term stability at high temperature, thereby suggesting the potential application of HCNS in high‐temperature filtration.

A composite membrane of sulfonated poly(ether sulfone) (SPES)/poly(ether sulfone) (PES) nanofiber (NF) mat impregnated with Nafion was prepared and evaluated for its potential use as a proton conductor for proton exchange membrane (PEM) fuel cells. The supporting composite nanofibrous mat was prepared by solution blowing of a mixture of SPES/PES solution. The characteristics of the SPES/PES NF and the composite membrane, such as morphology, thermal stability, and performance of membrane as PEMs, were investigated. The performance of composite membranes was compared with that of Nafion117. The introduction of solution blown NFs to composite membranes modestly improved proton conductivity, water swelling, and methanol permeability. Therefore, composite membrane containing SPES/PES NFs can be considered as a novel PEM for fuel cell applications. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42572.

Increasing attention has been given to nanofiber fabrication techniques. Solution blow spinning (SBS) is an innovative, simple, and effective method for producing nanofibers, and it only uses the drawing force of high-velocity airflow. However, solution-blown nanofibers easily form bundles; this results in an uneven distribution of nanofibers and an inhomogeneity of nanofiber mats. In this study, electrostatic-induction-assisted solution blow spinning (EISBS) was established by the introduction of an additional electrostatic field with an induction circle electrode into the SBS system. The effects of the electrostatic force on the fiber configuration and structure were examined. The results indicate that the electrostatic field effectively separated the fibers. Response surface methodology, based on the four-factor, three-level Box–Behnken design, was used to facilitate a more systematic understanding of the processing parameters of EISBS. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42326.

To introduce N-methylmorpholine-N-oxide (NMMO) process to prepare antibacterial lyocell fiber, the blend films of O-carboxymethyl chitosan (O-CMCS) and cellulose were prepared. O-CMCS in aqueous suspension with particles having a surface mean diameter of 2.24 μm was blended with cellulose in NMMO hydrate. The blend films with different O-CMCS content were prepared with the blend solutions. SEM confirmed that O-CMCS remained within the cellulose film in the particle. The mechanical properties of the blend films show little increased value when O-CMCS was less 5%; however, it decreased sharply when O-CMCS was over 8%. Thus, the optimum O-CMCS content may give a good combination of antibacterial action and mechanical properties.

An O−carboxymethylated chitosan (O− CMCh) water solution (I) and N,N-dimethylacetamide (DMAc) emulsion (II) were blended with a cellulose LiCl/DMAc solution, and corresponding polyblends (Polyblends I and II) were obtained. The rheology of the three fluids, that is, the cellulose solution and Polyblends I and II, was investigated. The cellulose solution was characterized by a power-law fluid. When an O-CMCh water solution or DMAc emulsion was added to the cellulose solution, the power-law curve was preserved. The power-law indexes (n) of all three fluids increased along with the temperature. Polyblend I displays an n close to but a little higher than that of the cellulose solution, while Polyblend II shows a much higher power index than those of the other two fluids. The values of the apparent viscosity (ηa) for all the three fluids are close and decrease along with an increase in the temperature. Adding O-CMCh microparticles into Polyblends I and II results in a decrease in the structural viscosity index (Δη) in comparison to that of the cellulose solution, and this effect is very obvious for Polyblend I. A cellulose solution's Δη declines with the augmentation of temperature, while the Δη's of both Polyblends I and II show minimum values at about 323 K. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1719–1725, 2003

Chitosan/N,O-carboxymethylated chitosan/viscose rayon antibacterial fibers (CNVFs) were prepared by blending chitosan emulsion, N,O-carboxymethylated chitosan (N,O-CMC), and viscose rayon together for spinning. The fibers were characterized by transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). TEM micrographs showed that chitosan microparticles dispersed uniformly along the oriented direction with the mean size ranging from 0.1 to 0.5 μm. DSC spectra of these fibers showed that no significant change in thermal property was caused by adding chitosan and N,O-CMC into the viscose rayon. TGA spectra showed that the good moisture retentivity was not affected by the addition of chitosan and N,O-CMC. Both DSC and TGA suggested that the decomposing tendency of the viscose rayon above 250°C seemed to be weakened by the chitosan. The fibers' mechanical properties and antibacterial activities against Escherchia coli,Staphylococcus aureus, and Candida albicans were measured. Although the addition of chitosan slightly reduced the mechanical properties, the antibacterial fibers' properties were obtained and were found to meet commercial requirements. CNVF exhibited excellent antibacterial activity against E. coli,S. aureus, and C. albicans. The antibacterial activity increased along with the chitosan concentration and was not greatly affected by 15 washings in water. Scanning electron microscopy (SEM) was used to observe the morphology of bacteria cells incubated together with the antibacterial or reference fibers. SEM micrographs demonstrated that greater amounts of bacteria could be adsorbed by the antibacterial fiber than by the reference fiber; these bacteria were overwhelmingly destroyed and killed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2049–2059, 2002; DOI 10.1002/app.10501