Knowing the reflection, transmission, and absorption properties of the yarns from which the woven fabric is made, prediction of a fabric’s UV-protective properties is simple. Using the geometrical ...properties of monofilament yarns and fabrics, which were determined optically, and following the cover factor theory, we have determined the areas of fabrics covered with no yarns, only one yarn, and two yarns. From a special selected set of high-module polyethylene terephthalate (PET) monofilament materials (e.g., fabrics), we have elaborated a method for determining the reflection, transmission, and absorption of yarns. By first defining the differently covered areas of fabrics, we were able to use them in a mathematical model for calculating and predicting the UV-protective properties of the fabrics. The calculated and measured values of the UV-protective properties of the selected test fabrics were highly correlated, with a correlation coefficient >0.98.
The desire to offer clothes protective properties against the harmful UV rays continues to attract the interest of researchers. Several works have been elaborated in this topic and have proved that ...the clothes do not protect sufficiently against the solar ultraviolet radiation. Their protectiveness depends on the fiber type, the fabric composition, the fabric construction and the dyeing method. This research presents a novel approach which target the improvement of the textile protective properties against UV rays by their dyeing with grape pomace aqueous extract. These properties were tested in combination with several fabrics (natural and synthetic) and mordants (potassium alum and ferrous sulphate). Through this study, it has been shown that the UV-protective properties of the several dyed fibers were upgraded after dyeing with the grape pomace extract, and is intensely relying on the types of fibers and mordants.
In this work, a novel cerium-based anti-ultraviolet fiber (CAUF) was prepared by masterbatch method for the first time. A pigment material, nano-cerium phosphate (nano-CePO
4
) was modified by ...aluminate coupling agent and then applied as the cerium-based anti-ultraviolet agent (CAUA) in the preparation of masterbatch. The characteristics of anti-ultraviolet agent, masterbatch and fibers were investigated by Fourier transform infrared spectroscopy, electron microscopy, differential scanning calorimeter, X-ray diffractometer, contact angle meter and ultraviolet spectrophotometer. The results indicated that masterbatch with the CAUA content of 10 wt.% could achieve the excellent dispersion of nanoparticles in PET matrix and improve the compatibility between nanoparticles and PET matrix, which was chosen for spinning. As the content of masterbatch (CAUA) in fibers reached to 15 wt.% (1.5 wt.%), not only the good physical–mechanical properties of fibers were achieved, but also the ultraviolet transmittance of fibers in UVA and UVB bands decreased to 2.27% and 0.57%, which presented the better anti-ultraviolet property than nano-titanium dioxide. Therefore, surface modified nano-CePO
4
is a promising inorganic anti-ultraviolet agent with great chemical inertia, low photocatalytic activity and high absorption in the UV region, which could endow fibers with excellent protection properties in both UVA and UVB bands.
The aim of this study is to investigate the effects of chemical treated halloysite nanotube (HNT) on the optical and UV-protective properties of poly(lactic acid) (PLA) nanocomposites. Two strategies ...were used to modify the HNT, i.e., sodium dodecyl sulfate (SDS) surface modification and zinc oxide (ZnO) immobilization on HNT. The Si-O index measurement via Fourier transform infrared (FTIR) spectroscopy analysis proved that chemical interaction occurred between HNT and SDS. Transmission electron microscopy (TEM) evidenced that the ZnO nanoparticles were successfully immobilized on the HNT surface. PLA/treated HNT nanocomposites were prepared using melt compounding followed by compression molding. The PLA/HNT nanocomposites were characterized by UV-visible spectroscopy (UV-Vis). The visible-shielding ratio (VR) and UV-blocking ratio (UVR) of the PLA/HNT nanocomposite films were determined. Both PLA/SDS-treated HNT and PLA/ZnO treated HNT nanocomposites exhibited higher UV-blocking property compared to that of PLA/untreated HNT nanocomposites.
Curcumin is a natural dye used in a wide variety of applications including textiles. In this study, it was attempted to determine whether curcumin can be modified for mordant-free coloring of ...textiles. Curcumin was chemically modified in aqueous system using glycidyltrimethylammonium chloride. The modified product called CurGTMAC was analyzed for structure by mass spectroscopy and examined for absorption properties. Results showed that its absorbance significantly shifted to UV region with an extinction coefficient high enough to function as a natural-based dye with UV protective properties. After applying CurGTMAC to cotton fabrics pre-treated with citric acid and sodium hypophosphite, excellent UV protection property and good durability to home laundering were obtained, possibly due to ionic interaction between cellulose citrate groups and CurGTMAC cations. These promising results suggest a new approach to dye cationic curcumin on cotton in the absence of mordants.
Resonant wave mixing is a promising technology based on employing non-linear waves to intensify heat and mass transfer and enhancing dispersion processes in mixed materials. In the present work, for ...the first time, resonant wave mixing was used to prepare film-forming dispersions based on gelatinized maize starch and spherical TiO
2
nanoparticles (0.5–1.5 wt%) synthesized by sol–gel technique. Then, nanocomposite films were obtained by solution casting method. The dynamic viscoelastic properties, including relaxation spectra of the film-forming dispersions were investigated by oscillatory squeeze film rheometry, while the structure of the nanocomposite films was studied by X-ray diffraction, FTIR spectroscopy and scanning electron microscopy. The mechanical, water-related and UV-protective properties of the film materials were evaluated. It was shown that nanofiller incorporation enhanced the density of the 3D network structure of a gelatinized starch dispersion. The resonant wave treatment favored homogenous dispersion of the TiO
2
nanoparticles in the nanocomposites. All nanocomposite film samples displayed higher tensile strength and lower water vapor permeability in comparison with starch films without the nanofiller. The obtained nanocomposites possessed UV-protective properties, which could be potentially applied to produce biodegradable packaging materials with improved functional characteristics.
The aim of our work was to establish whether very good to excellent UV (ultraviolet) protective properties of fabrics can be obtained through a suitable fabric construction and yarn colour, at the ...same time ensuring suitable air permeability.
For this purpose, six different fabric structures divided into three groups were employed. The samples were made in blue and red combinations of weft with different sequences and proportions between the upper and lower weave threads. A comparison of different fabric structures and colours was attempted to enable the assessment of the impact of the mentioned parameters on both, UV protective properties and air permeability of fabrics.
The analysis comprised the investigation of physical and permeability properties, as well as the colour measurements on twelve different cotton fabrics.
The research indicated excellent UV protection (>60) in all samples. UV protection depended on their construction and in a sufficiently closed structure, also on the colour of the used yarn. There was no significant difference between the samples in blue and red. In addition to excellent UV protection, four samples (one double-weft and three double fabrics) also demonstrated very high air permeability, which was 3–5 times higher than in the one-layer sample, which demonstrated the best UV protective properties.
The research has shown that fabrics with a very high ultraviolet protective factor value and good air permeability can be made by using a suitable construction and yarn colours that sufficiently absorb UV light; the latter being particularly important for light summer cotton clothes.
The oppositely charged titanium dioxide (TiO
2
) nanoparticles were deposited on the surface of poly(ethylene terephthalate) (PET) substrates by a layer-by-layer (LBL) assembly method. The PET films ...were pretreated by concentrated alkaline solution so as to introduce functional groups to attract TiO
2
nanoparticles onto the surface. The oppositely charged TiO
2
nanoparticles in the suspension can be controlled by adjusting the pH value. The multilayer buildup was monitored by UV-vis spectroscopy, which showed a linear increase of the film absorbance with the number of adsorbed TiO
2
layers. Moreover, the morphology, structural, and chemical composition of the multilayer nanocomposite films were analyzed by scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results confirmed the presence and even distribution of TiO
2
nanoparticles on the PET surfaces. The UV protective properties, thermal stability, and mechanical properties of the nanocomposite films were investigated. The values of ultraviolet protection factor (UPF) showed that the multilayer nanocomposite films exhibited high UV protective property. The TGA curves showed that TiO
2
nanoparticles enhanced the thermal stability of nanocomposite films. Additionally, the nanocomposite films showed a lower tensile strength but a higher elongation than that of PET film.
The purpose of this study was to investigate the possible influence of different emulsification methods and formulation composition such as emulsifier type, emulsifier concentration, liquid oil type ...and film-forming agents on the matrix carrier and its comprehensive influence on the UV-protective property of UV-filters. Different particle size of sunscreen emulsions were prepared by different emulsification methods with the same concentration on UVA filters only or combined UVB filters. The size and size distribution of the droplets were analyzed by dynamic light scattering, and the UV protective property was evaluated by UV-Vis absorption spectroscopy in solution and 3 M tape methods. The results showed the synergistic UV protection effect could be realized when the particle size of the matrix carrier was equivalent with the wavelength of the ultraviolet light at the same UV filters dosage. In addition, liquid oil also affected the UV protection performance of sunscreen by the intermiscibility and homogeneity with the UV filters. The addition of film-forming polymers made all system had good UV absorption properties.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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