Simple regulation of dielectric pulsing properties of polyethylene glycol‐poly(vinylidene fluoride) coaxial nanofiber films based on blow‐spinning process

Abstract

Understanding the relationship between the fabrication process and the dielectric behavior of thermo‐responsive dielectric materials and accordingly optimizing the dielectric response behavior through simple regulation is critical to advancing their practical applications. For this purpose, we systematically analyze and demonstrate the effects of blow‐spinning process parameters, the feed rate and airflow pressure, on the orientation of poly(vinylidene fluoride) (PVDF) chains, the individual phase fractions of PVDF, the structure of the core‐sheath nanofibers, the mechanical properties, and the dielectric pulsing properties in polyethylene glycol (PEG)‐PVDF core‐sheath fiber films, and achieve the goal of effectively regulating the thermo‐responsive dielectric behavior. In particular, by increasing the airflow pressure, the polar phase fraction of the PVDF can be effectively increased, thus strengthening the dielectric pulsing effect. The significant influence of the processing parameters on the nanofiber structure also allows us to tailor the strength and toughness of the nanofiber films over a wide range by adjusting the feed rate and airflow pressure. Our work shows that the regulation of feed rate and airflow pressure can be used as an effective strategy to optimize the dielectric pulsing and mechanical properties of PEG‐PVDF films, enabling a simple and low‐cost performance optimization of thermo‐responsive dielectric materials.Highlights Effective regulation of thermal dielectric behavior by tuning process parameters. Simple tuning of mechanical properties of nanofiber films over a wide range. High ratio of β‐ and γ‐phases of PVDF by solution blow spinning. Major polar phases contribute to improved mechanical and dielectric properties.

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

“…Ho et al used blow spinning to prepare a vertically stacked SWCNT/PVDF-HFP-SWCNT /PVDF-HFP-PVDF-HFP fabric capacitive strain sensor showing a high capacitance of 134 GF with a minimum detectable strain of 0.03%, validating the use of blow spinning technology in various textile electronic applications, which promised to open up a new era of wearable electronics [28]. Numerous studies used PVDF fibers prepared by blowing spinning to make nanogenerators or sensors for wearable applications to harvest energy from actions of human or monitor body health monitoring [29][30][31][32]. However, few researches using PVDF fibers prepared by blow spinning for SHM in engineering structures have been conducted.…”