Electrospun poly(methyl methacrylate) fibrous mat showing piezoelectric properties

Abstract

A piezoelectric effect, such as actuation behavior with voltage application, could be observed from a poly(methyl methacrylate) (PMMA) fibrous mat fabricated by electrospinning. This fibrous mat increased or decreased its thickness in accordance with the polarity of the applied voltage, which appears to be an inverse piezoelectric effect. The appearance d T constant was as large as 8.5 nm/V owing to the softness of the fibrous structure, and the coupling constant K T = 0.31 indicated its efficient piezoelectric property. This piezoelectric behavior was repeatedly observed to be stable at room temperature. In addition, the polarization components of the fibrous mat, which are considered to be the origin of its piezoelectric effect, and its relaxation behavior were confirmed from the results of thermally stimulated current measurements.

Fabrication of Pressure Sensor Using Electrospinning Method for Robotic Tactile Sensing Application

“…Regardless, tactile sensors such as capacitive, optical, magnetic, and piezoelectric types are expensive due to high fabrication costs. On the other hand, converse electromechanical responses were observed inadvertently with electrospun submicron/micron fiber mats composed of nonpiezoelectric polymers, such as poly(d,l-lactic acid (PDLLA), [ 21 ] poly(methyl methacrylate) (PMMA) and recently polystyrene (PS). In this article, we demonstrated the piezoelectric effect from atactic polystyrene (aPS) material and fabricated microfibers using an electrospinning method.…”

“…On the other hand, converse electromechanical responses were observed inadvertently with electrospun submicron/micron fiber mats composed of nonpiezoelectric polymers, such as poly(D,L-lactic acid (PDLLA), [ 21 ] poly(methyl methacrylate) (PMMA) [ 21 ], and their composites [ 22 ]. These non-piezoelectric materials exhibit piezoelectric properties like conventional piezoelectric materials, indicating a significant high apparent piezoelectric constant , as high as 8500 pm V −1 for an individual material [ 21 ] and 29,000 pm V −1 for a composite material [ 22 ]. These papers also reported that these excellent electromechanical properties are partly or mainly attributed to the unique electrically charged and mechanically soft nature of the electrospun fiber mats.…”

Electromechanically Active As‐Electrospun Polystyrene Fiber Mat: Significantly High Quasistatic/Dynamic Electromechanical Response and Theoretical Modeling

“…[ 8,9,14 ] Many groups have reported the piezoelectric properties of electrospun submicron/micron fibers composed of different piezoelectric polymers, such as poly(vinylidene fluoride) (PVDF), [ 8,10,15,16 ] poly(vinylidenefluoride‐co‐trifluoroethylene) (PVDF‐TrFE), [ 9,14,17–19 ] and poly( l ‐lactic acid) (PLLA), [ 20,21 ] and composites of piezoelectric materials. [ 22–24 ] Meanwhile, recently, converse electromechanical responses similar to the converse piezoelectric responses of piezoelectric materials have been observed inadvertently with electrospun submicron/micron fiber mats composed of nonpiezoelectric polymers, such as poly( d,l ‐lactic acid) (PDLLA), [ 25 ] poly(methyl methacrylate) (PMMA), [ 26 ] and their composites. [ 27 ] In general, nonpiezoelectric polymers do not show electromechanical properties in the film form.…”

“…[ 27 ] In general, nonpiezoelectric polymers do not show electromechanical properties in the film form. However, the quasistatic converse electromechanical characterizations of the electrospun fiber mats of nonpiezoelectric polymers have indicated significantly high apparent piezoelectric d constant ( d app ), as high as 8500 pm V −1 for an individual material [ 25,26 ] and 29 000 pm V −1 for a composite material. [ 27 ] Further, despite the observation of these unique properties of various nonpiezoelectric polymers and their composites, theoretical modeling, and analysis of the observed converse electromechanical responses have not been reported.…”

“…The very soft and modestly charged nature of the fiber mat should be the origin of the significantly high d app1 , as indicated by Equation (). As the as‐electrospun fiber mats of other nonpiezoelectric polymers, such as PMMA [ 26 ] and PDLLA, [ 25 ] have also shown relatively high quasistatic converse electromechanical characteristics, it can be inferred that the fiber mats of different polymers can potentially show electromechanical characteristics. Meanwhile, the chargeability and charge‐holding capacity of the fiber mats (σ Eff0 ) and the softness of the fiber mats ( Y C and Y D ) determine the d app , according to Equations () and ().…”