Thermal stability of piezoelectricity in polylactide polymers and related piezoelectric minimotor application
Jinxi Zhang, Yonggui Wang, Junyuan Tian, Xiangchen Xu, Weidong Wang, Kailiang Ren
Abstract
Abstract Piezoelectric polymers have been widely used in a variety of applications, including tactile sensors, energy harvesting, polymer actuators, and biological devices. In this investigation, we fabricated the PLLA (poly(L‐lactic Acid)‐based bimorph structures for piezoelectric motor applications. First, a strain measurement setup was established to measure the strain of the PLLA and PDLA film at different temperatures. The effective piezoelectric constants d 14 calculated for the PLLA and PDLA films were 10.2 pC/N and 9.4 pC/N, respectively. Furthermore, the PLLA films showed a strong thermostability of piezoelectricity at 130°C. The PLLA bimorph minimotor showed the maximum load of 1.2 g and the maximum torque of 0.019 cN·m. The minimotors were capable of rotating a plastic hemisphere container in the clockwise and counterclockwise directions at 65 V voltage. Due to the light weight, low driving voltage, and thermal stability, the PLLA/PDLA motors show a great promise in future Braille display, robots, and mini‐digital camera applications.