Polypropylene melt-blown nonwovens containing thick polycarbonate (PC) fibers were fabricated by a one-step extrusion process. The effects of the PC fibers on the thermal shrinkage and performance of Li-ion battery separators were assessed. PC fibers of 15–30 μm diameter were confirmed by scanning electron microscopy and X-ray computed tomography. An increase in PC fiber fraction was found to decrease the thermal shrinkage and increase the pore diameter and its distribution. The PC-containing samples showed no shrinkage under 130 ºC by thermomechanical analysis and under 100 ºC by free-end heat treatment. The PC fibers had little effect on battery performance at C-rates of 0.1–0.3. However, for C-rates of 5 and 10, a decrease in discharge capacity was observed when the PC content reached 88 %. The decrease of the discharge capacity for high C-rates may be caused by the increase in pore diameter distribution. These results demonstrate the importance of optimizing the PC fraction of nonwovens for use as Li-ion battery separators to minimize their decrease in discharge capacity while maintaining their thermal stability.

Nanofibers (NFs) produced by the electrospinning method have attracted much attention as cell culture scaffolds. On the other hand, olefinic polymers such as polypropylene (PP) can only be made into fibers and NFs by the melt-blown method due to the lack of solvent. We have succeeded in making PP-NF nonwoven fabrics with an average fiber diameter of 570 nm by controlling the amount of polymer pellets fed into the nozzle using the melt-blown method. This PP-NF nonwoven fabric showed excellent performance as a scaffold for Vero cell culture, which is necessary to make a vaccine for the SARS-CoV-2 coronavirus.

Appearance and compression property of tufted wool carpet modified by chlorination and enzyme treatment was examined. Compression and recovery of tufted carpet modified by DCCA and enzyme treatment was max value. Entropy and contrast from YCbCr image of tufted carpet image modified by chlorination and enzyme treatment was minimum. When wool yarn was modified by both chlorination and enzyme treatment, the change of feature after enzyme treatment was different from DCCA or sodium hypochlorite. Enzymatic treatment after chlorination in conc. is effective in improving the appearance and compression property of tufted wool carpet.

For environmental friendliness, new coloring methods are required to replace dyeing of textile products. Cellulose derivatives forming a cholesteric liquid crystal (CLC) structure under a room condition were synthesized by the esterification of hydroxypropyl cellulose (HPC) with propionic anhydride. Structural colored fibers were prepared by wet spinning from the acetone solution of these cellulose derivatives to water as a coagulation bath and liquid-crystallizing by removing water in the fiber under controlled humidity. The pitch of CLC structure was decreased with increasing fiber width deformation by self-weight under controlled humidity. The reflection intensity of CLC structure was increased with increasing the high shear rate at the wet spinning, lowering the degree of esterification, and lowing the rate to form CLC structures by controlled humidity. The fiber improved its reflection strength when it was kept under higher humidity above 80 % RH after crystallization via removing the water in the fiber. The fiber improved its pitch of CLC, when it was kept under higher humidity above 95 % RH and higher temperature bellow 50 ºC after liquid crystallization via removing the water in the fiber.

Polypropylene (PP) and polyethylene terephthalate (PET) nonwoven fabrics were treated with a mixed aqueous solution of sodium carboxymethylcellulose (CMC) and iron lactate (FeLac), and their ventilation resistance R, coefficient of kinetic friction μ and electrification voltage V were measured to evaluate the changes in physical properties due to the treatment. The results showed the following: The R of the PP and PET nonwovens increased with processing treatment with CMC and FeLac mixed aqueous solutions, and was greater for PET nonwovens than for PP ones. The R of the treated fabrics increases with increase in the concentration of CMC in the treatment solution. The R of the CMC + FeLac treated fabrics is slightly lower at a moisture content of less than 5.4 % than in the dry state, whereas it increases as the moisture content increases to several hundred percent. The μ of PP and PET nonwovens increases with CMC + FeLac treatment and is even higher at higher moisture contents. Furthermore, the V of PP and PET nonwovens are suppressed by the CMC + FeLac treatment.