The notion of ceramics going together with fabrics is a little counterintuitive. Mixing the hard stuff with soft threads? But, it’s true, and sort of like peanuts on top of an ice cream sundae—a great combination can occur. Actually, it’s really not all that counterintuitive if one considers just one application developed years ago that must have seemed a little hard to believe when it was introduced: fiberglass.
There are several groups of researchers that have been experimenting with blending ceramic materials and fabrics, yielding applications that range from the relativey simple to the extremely novel and robust.
For example, at the simple end of the spectrum, shirts are now available that claim to permanently incorporate sunblocking materials into their threads. That seems great to me. As a runner and someone who has already had one run-in with cancer, I am very watchful (if not a little paranoid) about sun exposure and wear long sleeve shirts outdoors (even when swimming). Cotton or cotton-blends seem to do a good job of blocking the sun, but hold perspiration like a sponge. As an alternative, I tried wearing some of the lightweight synthetic “wicking” shirts designed for sports, but I always wondered whether the meshy material was blocking all of the UV rays.
That was before I ran across Coolibar long sleeve athletic shirts. Coolibar claims to be the first company to “develop UPF 50+ apparel and hats using a proprietary fabric with zinc oxide that cannot be absorbed by the skin, cannot wear or wash off and safely deflects all UV rays.” Coolibar also makes attire with another UPF 50 fabric that contains TiO2. (The UPF designation is the fabric corollary to the SPF system for sunscreens.) Coolibar says its fabrics have been evaluated by an independent lab following testing and labeling standards established by ASTM (D6544 and D123) and the American Association of Textile Chemists and Colorists. I just purchased several of these shirts and look forward to testing them during the rest of the summer.
Coolibar’s apparel is an example of ceramic science joining up with textiles that is easy to understand. A bigger stretch is some of the work being conducted at North Carolina State University, and reported in the new August issue of ACerS’ Bulletin, where researchers are experimenting with some novel ceramic surface treatments of textiles.
One NCSU group is using atomic layer disposition to expand the boundary of traditional textiles by exploiting the conducting and semiconducting properties of ceramic nanoscale materials. Jesse S. Jur and Gregory N. Parsons, professors at NCSU, discuss in one of the Bulletin stories how ALD-processing can be used for the fabrication of electronic devices using textiles. They note, for example, that ALD can be used to create building blocks for responsive sensors. “The nanoscale surface coverage of ALD offers the ability to fabricate device layers that take advantage of the high surface area and strategic structure-property relations available through the use of a textile substrate,” Jur and Parsons report. “This is important in the formation of responsive materials with electrical behavior that changes when flexed or exposed to certain chemicals, that is, fabrics that act as platforms for all-fiber-based electronic devices.” Jur and Parsons detail some of the materials being examined as well as the challenges to scaling up high-throughput ALD techniques, and they sketch a future where applications for surface-modified textiles (woven and nonwoven) go well beyond traditional clothing, furnishings and protective coverings.
Another Bulletin story, by Tiina Nypelö and Orlando J. Rojas, focuses on the combination of ceramic materials and cellulose to create new types of functionalized fibers. Nypelö, a postdoctoral student, and Rojas, another NCSU professor, report on the use of coatings of clay, calcium carbonate, TiO2, silica and magnetic particles on emerging cellulose-based materials. They describe organic-inorganic hybrid fibers that could be used for flexible, printed electronics, circuit board bases, sensors, actuators and resistance temperature detectors as well as conductive, magnetic and piezoelectric films.
Thus, from shirts to sensors, it seems that the emerging ceramics–fabrics mashup isn’t all that odd, and, the benefits loom large.