Fabrication of core–sheath structured smart nanofibers loaded with Cs x WO 3 by coaxial electrospinning which demonstrate high heat capacity and NIR absorbance.
High thermostability of phase change materials is the critical factor for producing phase change thermoregulated fiber (PCTF) by melt spinning. To achieve the production of PCTF from melt spinning, a composite phase change material with high thermostability was developed, and a sheath-core structure of PCTF was also developed from bicomponent melt spinning. The sheath layer was polyamide 6, and the core layer was made from a composite of polyethylene and paraffin. The PCTF was characterized by scanning electron microscopy (SEM), thermal analysis (TG), Fourier Transform Infra-Red (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and fiber strength tester. The results showed that the core material had a very high thermostability at a volatilization temperature of 235 °C, the PCTF had an endothermic and exothermic process in the temperature range of 20–30 °C, and the maximum latent heat of the PCTF reached 20.11 J/g. The tenacity of the PCTF gradually decreased and then reached a stable state with the increase of temperature from −25 °C to 80 °C. The PCTF had a tenacity of 343.59 MPa at 0 °C, and of 254.63 MPa at 25 °C, which fully meets the application requirements of fiber in textiles.
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer known for its excellent hydrophobic properties. In this work, samples from PTFE dispersions with different combinations of water and carbon microparticles were prepared using an electrospraying method. The morphologies and sizes of carbon particles were investigated and the properties of layers including roughness, hydrophobicity and electrical resistivity were investigated. The non-conductive carbon microparticles were selected as a model particle to check the compatibility and electrospraying ability, and it had no effect on the hydrophobic and electrical properties. Carbon microparticles in polymer solution increased the degree of ionization and was found to be beneficial for the shape control of materials. The results showed that PTFE dispersion with the composition of water and carbon microparticles produced fine sphere particles and the layer fabricated with increased roughness. It was also found that the electrical resistivity and hydrophobicity of all the layers comparatively increased. The fabricated microporous layers can be used in various applications like interlining layer in multilayer textile sandwiches.
P-aminophenol is a hazardous environmental pollutant that can remain in water in the natural environment for long periods due to its resistance to microbiological degradation. In order to decompose p-aminophenol in water, manganese oxide/polytetrafluoroethylene (PTFE) hollow fiber membranes were prepared. MnO2 and Mn3O4 were synthesized and stored in PTFE hollow fiber membranes by injecting MnSO4·H2O, KMnO4, NaOH, and H2O2 solutions into the pores of the PTFE hollow fiber membrane. The resultant MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were characterized using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermal analysis (TG). The phenol catalytic degradation performance of the hollow fiber membranes was evaluated under various conditions, including flux, oxidant content, and pH. The results showed that a weak acid environment and a decrease in flux were beneficial to the catalytic degradation performance of manganese oxide/PTFE hollow fiber membranes. The catalytic degradation efficiencies of the MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were 70% and 37% when a certain concentration of potassium monopersulfate (PMS) was added, and the catalytic degradation efficiencies of MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were 50% and 35% when a certain concentration of H2O2 was added. Therefore, the manganese oxide/PTFE hollow fiber membranes represent a good solution for the decomposition of p-aminophenol.
Structural-colored fabrics have been attracting much attention due to their eco-friendliness, dyelessness, and anti-fading properties. Monodisperse microspheres of metal, metal oxide, and semiconductors are promising materials for creating photonic crystals and structural colors owing to their high refractive indices. Herein, Cu2O microspheres were prepared by a two-step reduction method at room temperature; the size of Cu2O microspheres was controlled by changing the molar ratio of citrate to Cu2+; and the size of Cu2O microspheres was tuned from 275 nm to 190 nm. The Cu2O microsphere dispersions were prepared with the monodispersity of Cu2O microspheres. Furthermore, the effect of the concentration of Cu2O microsphere and poly(butyl acrylate) on the structural color was also evaluated. Finally, the stability of the structural color against friction and bending was also tested. The results demonstrated that the different structural colors of fabrics were achieved by adjusting the size of the Cu2O microsphere, and the color fastness of the structural color was improved by using poly(butyl acrylate) as the adhesive.