3 research outputs found
PEDOT:PSS âWiresâ Printed on Textile for Wearable Electronics
Herein, the fabrication of all-organic
conductive wires is demonstrated
by utilizing patterning techniques such as inkjet printing and sponge
stencil to apply polyÂ(3,4-ethylenedioxythiophene) polystyrenesulfonate
(PEDOT:PSS) onto nonwoven polyethylene terephthalate (PET) fabric.
The coating of the conducting polymer is only present on the surface
of the substrate (penetration depth ⌠200 Όm) to retain
the functionality and wearability of the textile. The wires fabricated
by different patterning techniques provide a wide range of resistance,
i.e., tens of kΩ/⥠to less than 2 Ω/⥠that
allows the resistance to be tailored to a specific application. The
sheet resistance is measured to be as low as 1.6 Ω/âĄ,
and the breakdown current is as high as 0.37 A for a 1 mm wide line.
The specific breakdown current exceeds the previously reported values
of macroscopic carbon nanotube based materials. Simple circuits composed
of the printed wires are demonstrated, and resistance of the circuit
from the measurement agrees with the calculated value based on Kirchhoffâs
rules. Additionally, the printed PEDOT:PSS wires show less than 6.2%
change in sheet resistance after three washing and drying cycles using
detergent
Screen-Printed PEDOT:PSS Electrodes on Commercial Finished Textiles for Electrocardiography
Electrocardiography
(ECG) is an essential technique for analyzing
and monitoring cardiovascular physiological conditions such as arrhythmia.
This article demonstrates the integration of screen-printed ECG circuitry
from a commercially available conducting polymer, PEDOT:PSS, onto
commercially available finished textiles. ECG signals were recorded
in dry skin conditions due to the ability of PEDOT:PSS to function
as both ionic and electronic conductors. The signal amplifies when
the skin transpires water vapor or by applying a common lotion on
the skin. Finally, PEDOT:PSS wires connected to PEDOT:PSS electrodes
have been shown to record ECG signals comparable to Ag/AgCl connected
to copper wires
Optimization of Organotin Polymers for Dielectric Applications
Recently,
there has been a growing interest in developing wide band gap dielectric
materials as the next generation insulators for capacitors, photovoltaic
devices, and transistors. Organotin polyesters have shown promise
as high dielectric constant, low loss, and high band gap materials.
Guided by first-principles calculations from density functional theory
(DFT), in line with the emerging codesign concept, the polymer polyÂ(dimethyltin
3,3-dimethylglutarate), pÂ(DMTDMG), was identified as a promising candidate
for dielectric applications. Blends and copolymers of polyÂ(dimethyltin
suberate), pÂ(DMTSub), and pÂ(DMTDMG) were compared using increasing
amounts of pÂ(DMTSub) from 10% to 50% to find a balance between electronic
properties and film morphology. DFT calculations were used to gain
further insight into the structural and electronic differences between
pÂ(DMTSub) and pÂ(DMTDMG). Both blend and copolymer systems showed improved
results over the homopolymers with the films having dielectric constants
of 6.8 and 6.7 at 10 kHz with losses of 1% and 2% for the blend and
copolymer systems, respectively. The energy density of the film measured
as a <i>D</i>â<i>E</i> hysteresis loop
was 6 J/cc for the copolymer, showing an improvement compared to 4
J/cc for the blend. This improvement is hypothesized to come from
a more uniform distribution of diacid repeat units in the copolymer
compared to the blend, leading toward improved film quality and subsequently
higher energy density