Highly Stretchable and Conductive Polymer Material Made from Poly(3,4‐ethylenedioxythiophene) and Polyurethane Elastomers

Abstract

A highly elastic and stretchable conductive polymer material resulted from blending the conductive polymer poly(3,4‐ethylenedioxythiophene):p‐tosylate and an aliphatic polyurethane elastomer. The blend inherited advantageous properties from its constituents, namely high conductivity of 120 S cm–1 from its conductive polymer component, and elastomeric mechanical properties resembling those of the polyurethane, including good adhesion to various substrates. Stretching of the blend material by up to 50 % resulted in increased conductivity, while subsequent relaxation to the unstretched state caused a decrease of conductivity compared to the pristine blend. These initial changes in conductivity were reproducible on further cycling between 50 % stretching and the unstretched state for at least 10 cycles. Stretching beyond 50 % resulted in decreasing conductivity of the blend but with substantial conductivity remaining even when stretched by 200 %. Optical, mechanical, and thermal properties of the blend, as well as high resolution electron microscopy of bulk cross‐sections, suggest that the system is a single phase and not two separate phases. Ageing experiments indicate that the material retains substantial conductivity for at least a few years at room temperature.

Structure and design of polymers for durable, stretchable organic electronics

“…130 The lack of phase segregation in the material was confirmed by AFM, and by DSC, which showed a mixing of the glass transitions, resulting in a T g intermediate between the two components' T g . This blend was conductively stable through four cycles of a high 200% strain.…”

“…This can be explained by the morphology of these usually immiscible blends; larger domains of conjugated polymer improve electrical properties but introduce more of its brittle character as its concentration increases. 125,130,131 An example is illustrated in Figure 15, where larger phases of conducting polymer and higher miscibility between polymers showed increased conductivity. 129 To maintain conductivity without greatly changing the mechanical properties of the rubber, low percolation thresholds of conjugated polymers are desirable.…”

Tuning chain extender structure to prepare high-performance thermoplastic polyurethane elastomers

“…As shown in Fig. S10, † the d shis of 13 C-NMR at 80.12 and 79.98 ppm corresponds to the cyclopentadienyl carbon which conrms the successful incorporation of ferrocenyl diol into the polymer via chain extension. Due to the steric and aromatic effect from the ferrocenyl molecular center, the d for C]O in urethane (-NH-COO-) shied from 155.88 ppm in BDO-PU to lower d shis in monoFc-PU and bisFc-PU polymers.…”

“…[2][3][4][5] Recently it also shows interesting applications in self-healing materials, [6][7][8] stimuliresponsive materials, [9][10][11][12] and exible conductive materials. 13 Meanwhile, concerns about the poor heat resistance of PUs limit their further applications. 14 The mechanical properties of PUs will be greatly reduced when the operating temperature is above 120 C.…”

Progress and Prospects in Stretchable Electroluminescent Devices

“…The conductor showed unique property with rapidly decreased resistance under increasing tensile strain, attributed to the increased conductive paths with more nickel powders in contacts under strain. Many other fillers, such as nanotubes, nanoplates, nanoparticles, and textiles, were also demonstrated to be promising materials that could be embedded into the elastic polymer matrix for stretchable electrodes [60][61][62][63][64][65][66].…”