Reversible Plastic Deformation of Polymer Blends as a Means to Achieve Stretchable Organic Transistors

Intrinsically stretchable semiconductors will facilitate the realization of seamlessly integrated stretchable electronics. However, to date demonstrations of intrinsically stretchable semiconductors have been limited. In this study, a new approach to achieve intrinsically stretchable semiconductors is introduced by blending a rigid high-performance donor-acceptor polymer semiconductor poly[4(4,4dihexadecyl4Hcyclopenta [1,2b:5,4b' ] dithiopen2yl) alt [1,2,5] thiadiazolo [3,4c] pyridine] (PCDTPT) with a ductile polymer semiconductor poly(3hexylthiophene) (P3HT). Under large tensile strains of up to 75%, the polymers are shown to orient in the direction of strain, and when the strain is reduced, the polymers reversibly deform. During cyclic strain, the local packing order of the polymers is shown to be remarkably stable. The saturated field effect charge mobility is shown to be consistently above 0.04 cm² V^-1s^-1 for up to 100 strain cycles with strain ranging from 10% to 75% when the film is printed onto a rigid test bed. At the 75% strain state, the charge mobility is consistently above 0.15 cm² V^-1s^-1. Ultimately, the polymer blend process introduced here results in an excellent combination of device performance and stretchability providing an effective approach to achieve intrinsically stretchable semiconductors.