SLRI researchers applied advanced science to develop and upgrade fabric from local natural fiber to surgical masks. The synchrotron technology was applied to analyze for three-dimensional (3D) structure, material and chemical properties, the main factors affecting mask filtration capacity, of the fabric. The study was conducted in comparing with structures and properties of disposable surgical masks and other masks made of different fibers and weaving patterns.
The X-ray Tomographic Microscopy (XTM) technique supported researchers to indicate characteristics of fiber, size of threads, weaving pattern, and space distribution within fabric in 3D model. The stated factors are significant to filtration capacity of different fabrics. The 3D analysis shows that fiber of natural Thai silk is smaller and constant longer than fabrics from synthetic fiber and enables tight weaving with small gaps. SLRI researchers then used the gained body of knowledge to design a new weaving pattern for Thai silk which made the woven fabric comparable to a surgical mask in term of dust and bacteria filtration. The newly designed weaving pattern uses three-twisted silk threads and plain weaving with two heddles. The silk fabric woven by the newly developed pattern achieves up to 85% of PM 2.5 and 0.3 micron filtration capacity which is much higher than a muslin-made mask can do at only 16-18% of capacity. Moreover, the Thai silk fabric also supports air circulation for long-wearing comfort.
SLRI researchers also implemented the in-situ Wide-angle X-ray Scattering (WAXS) technique to analyze crystal structure of the newly developed mask and found that silk contains stronger crystal structure and higher tensile strength than muslin does. Therefore, the silk fabric can be washed and reused without effect on fiber structure. SLRI researchers additionally used X-ray Absorption Near Edge Spectroscopy (XANES) and X-ray Fluorescence Spectroscopy (XRF) techniques and later reported the existence of ZnO distribution within silk fabric which is recognized as anti-bacterial agent.
This research is as a pilot project to demonstrate that advanced science and technology can be applied for analysis and development to upgrade local fabrics. The upgrading of fabrics can make fabrics with more value, not only to make fabric users look elegant but also the design can be made for different practical uses.
For the case of this research, the developed silk mask with higher filtration capacity achieves filtration capability standard and can be an alternative for a user as a surgical mask. In addition, the mask was environmentally friendly. Bodies of knowledge gained from this research are beneficial to design and development of innovation from various natural-fiber-fabrics in various patterns with required qualifications. Later, more employment and higher income will occur in local communities.