Nano titanium dioxide embedded nano fibers spun from electro spinning technology to produce stain removal and UV blocking nano fibers

Abstract

Titanium dioxide nano particle possess photo catalytic, chemical resistance and has the ability of blocking UV light. Reinforcing TiO₂ nano particles to nano fibers will give rise to specific properties such as UV blocking, stain removal and antibacterial properties. Electro spinning technology has the ability to produce nano fiber composites containing titanium dioxide nano particles which can be used to produce nonwoven fabrics or yarns with properties of UV blocking and stain removal. This nano scale modification to the composite will enhance the performance of the end product. Fabrics or nonwovens developed from nano fibers which contain the anti UV, self-cleaning and antibacterial properties are more durable and efficient than fabrics coated with conventional finishes.

During this research study a Nano fiber/TiO₂ composite was prepared by electro spinning a PAN/TiO₂ polymer (PAN with an average molecular weight of 10000 and anatase form of TiO₂ with an average particle size of 50-100 nm) solution in N,N’-dimethyl formamide (DMF), where all the chemicals and materials were from Sigma Aldrich, USA. Electro spinning allows forming a fiber composite with an aspect ratio in the range of 1000 and a high molecular orientation to the fiber. Scanning Electron Microscope (SEM) studies showed that the average diameter of the electro spun PAN/TiO₂ nano composite fibers was in the range of 250-300 nm with a homogenous diameter and revealed the presence of nano titanium dioxide particles embedded inside the nano fiber with an average particle size of 100 nm. UV-VIS spectroscopic studies showed the prepared nano composite can absorb UV light in the range of 200-350 nm. A model experiment showed the prepared nano composite can block the UV light compared to PAN nano fibers by 76%. Stain removal properties of the polymer nano composite were analyzed using the color reduction of an organic stain (Bromothymol Blue) under the sunlight. After 3 hours of sunlight exposure the color reduction was 84% present compared to color reduction of PAN nano fibers under same conditions of only 4%.