Kansai University, Osaka, Japan, and Teijin Ltd. have announced that Prof. Yoshiro Tajitsu, Engineering Science, Kansai University, and Teijin have developed what the company terms the world’s first polylactic acid (PLA) fiber- and carbon-fiber-based piezoelectric fabrics.
The new piezoelectric fabrics combine Teijin’s polymer and textile technologies with Prof. Tajitsu’s knowledge of piezoelectric materials. Piezoelectricity is the ability of certain dielectric materials to generate an electric charge in response to mechanical stress. It also has the opposite effect–the application of electric voltage produces mechanical strain in the materials. Both of these effects can be measured, making piezoelectric materials effective for both sensors and actuators.
The fabrics comprise a piezoelectric poly-L-lactic acid (PLLA) and carbon fiber electrode. A sensing function, which can detect arbitrary displacement or directional changes, incorporates Teijin’s weaving and knitting technologies. The function allows fabric to be applied to the actuator or sensor to detect complicated movements, even three-dimensional movements. Plain, twill and satin weave versions were produced for different applications: plain weave detects bending, satin weave detects twisting, and twill weave detects shear and three-dimensional motion, as well as bending and twisting.
The partnership previously developed a flexible, transparent piezoelectric film by alternately laminating PLLA and optical isomer poly-D-lactic acid (PDLA). The wearable piezoelectric fabric is the newest application of this technology. Development also received technological cooperation from the Industrial Technology Center of Fukui Prefecture.
The partnership will continue working on ideal weaves and knits for fabric applications that enable elaborate human actions to be monitored via clothing; this is expected to contribute to the evolution of the Internet of Things (IoT) in fields ranging from elderly care to surgery, artisanal techniques to space exploration.