PVDF piezoelectric sensor based on solution blow spinning fibers for structural stress/strain health monitoring

Abstract

Strain monitoring is of great significance to the maintenance and safe operation of engineering structures. To address the shortcomings of piezoelectric ceramics such as high inflexibility and brittleness, in this study, polyvinylidene fluoride (PVDF) fibrous films were prepared by a safe and efficient solution blow spinning technique. In the case of similar β-phase content, the preparing efficiency of PVDF fibers by the solution blow spinning method increased by about 8–10 times compared to that of electrospinning method in our previous work. The fibers with average diameter of 0.79 μm had the highest β-phase content, around 83%. A flexible piezoelectric fiber sensor with simple design for structural strain monitoring was prepared based on the PVDF fibers. The sensor responded well to strains as low as 23 μϵ, better than commercial strain gauges, with a high response accuracy of 1.11 mV/μϵ. And the piezoelectric properties of the sensors could charge a 4.7 μF capacitor to 3 V in 40 s, offering the potential for low-cost, self-powered structural health monitoring.