In order to explore the ultraviolet protection performance of nanofibers, the ultraviolet shielding nano titanium dioxide (TiO2) was added to the polyacrylonitrile (PAN) solution, and pure PAN and composite PAN/TiO2 nanofiber membranes were prepared. Scanning electron microscopy and UV transmittance analysis were used. The instrument analyzed the microscopic morphology and UV protection performance of nanofibers. The results show that the composite PAN/TiO2 nanofibers have a smaller diameter; the infrared spectrogram shows that PAN/TiO2 nanofibers not only contain the characteristic absorption peak of PAN, but also the characteristic absorption peak of TiO2. The addition of TiO2 effectively increases the UV absorption and UV protection properties of PAN/TiO2 hybrid nanofiber membranes. The UV protection factor (UPF) of pure PAN nanofiber membranes is 30.72, and the UPF of PAN/TiO2 nanofiber membranes is 1096.21～1865.49. And UPF increases with the increase of TiO2 mass fraction; when the TiO2 mass fraction is 0.5%, PAN/TiO2 nanofibers have a smooth surface, smaller diameter, and better UV protection performance.

Ultraviolet rays refer to electromagnetic waves with a wavelength range of 200 to 400 nm, which can be divided into UVA (3l5 to 400nm), UVB (280 to 3l5 nm), and UVC (200 to 280nm) according to their wavelengths. Short-term ultraviolet radiation is beneficial to the human body. It can not only sterilize and disinfect, but also promote the synthesis of vitamin D needed by the human body, which greatly reduces the probability of rickets. However, long-term ultraviolet radiation can cause great damage to the human body. UVA can easily cause people to tan, wrinkles, and accelerate skin aging; UVB can make the skin red, and even burn the skin to produce blisters. Long-term high-intensity irradiation can even induce skin cancer. UVB can be partially absorbed by the ozone layer; UVC is almost all absorbed by carbon dioxide in the atmosphere, and it is difficult to reach the ground. Therefore, the anti-ultraviolet radiation is mainly aimed at UVA and UVB. The anti-ultraviolet products that effectively protect humans from UVA and UVB have also become in recent years. Come to study the hot spots.

Pant et al. added titanium dioxide (TiO2) to the nylon 6 solution and prepared a nylon 6/TiO2 composite spider web nanofiber membrane by electrospinning. The results showed that a small amount of TiO2 and nylon 6 composite effectively improved the antifouling of the nanofiber membrane. Effect, mechanical strength, antibacterial and UV protection ability. Lee et al. prepared PU/ZnO nanofiber membranes by adding zinc oxide (ZnO) to the polyurethane (PU) solution, and composited the nanofiber membranes on the surface of cotton fabrics and polypropylene fabrics. The results showed that the PU/ZnO nanofiber membranes reduced The UV transmittance of the fabric effectively increases the UV protection performance of the fabric.

Inorganic ultraviolet shielding agents (such as ZnO, TiO2, etc.) are the most commonly used ultraviolet shielding agents, and nano-level shielding agents have a more obvious shielding effect on ultraviolet rays. Studies have shown that when ZnO, TiO2 and other ultraviolet shielding agents reach nano-scale size, they will exhibit excellent light absorption characteristics, can absorb a large amount of ultraviolet rays, and have excellent UV protection. The smaller the particles, the better the UV protection effect. The influence of fabric hand feel is also smaller.
The PAN nanofiber membrane has an obvious UV absorption peak at 260nm, and the absorption value drops significantly after 260nm until there is almost no absorption. The UV absorption value of PAN/TiO2 composite nanofiber membrane after adding TiO2 is significantly higher than that of pure PAN, and the UV absorption value of pure TiO2 powder is much higher than that of PAN/TiO2 composite nanofiber membrane. PAN/TiO2 nanofibers have relatively good absorption effects for ultraviolet rays between 200 and 325 nm, but the absorption value for ultraviolet rays greater than 320 nm drops sharply. It shows that PAN/TiO2 nanofibers and pure TiO2 powder have a good protective effect on medium-wave ultraviolet UVB. As the mass fraction of TiO2 increases, the greater the UV absorption value of PAN/TiO2 nanofibers, the better its UV protection performance.

The UPF of the pure PAN nanofiber membrane is 30.72, and the transmittances of UVA and UVB are 6.63% and 2.43%, respectively. According to the requirements of GB/T18830-2009 "Assessment of Anti-UV Performance of Standard Textiles", products with UPF greater than 40 are anti-ultraviolet Products, so PAN nanofiber membranes are not anti-ultraviolet products. After adding TiO2, due to the good UV absorption and UV shielding performance of TiO2, the UPF of PAN/TiO2 nanofiber membrane is 1096.21～1865.49, which is much larger than that of pure PAN nanofiber membrane, and with the increase of TiO2 mass fraction, nanofiber membrane The UPF increases. In addition, the UVA transmittance of PAN/TiO2 nanofiber film is 0.16% to 0.94%, which is much smaller than pure PAN, while the UVB transmittance is 0.05%.

The addition of trace nanometer TiO2 can make composite PAN/TiO2 nanofibers have excellent UV protection performance. Combined with the SEM photos of PAN/TiO2 nanofibers, it can be seen that when the mass fraction of nanometer TiO2 particles is 0.5%, PAN/TiO2 nanofibers have Smooth surface, small fiber diameter and very good UV protection performance.

SAT NANO can supply tio2 titanium dioxide nanopowder 10-20nm, 30-50nm particle, if you have any enquiry, please feel free to contact us at admin@satnano.com