외부효과 최소화를 통한 스트레처블 소자의 신축성 평가법 최적화

Abstract

Stretchable devices have the advantage of high portability with a larger area when they are used. Stretchability is an important evaluation parameter of stretchable devices. The standard test method for evaluating it has not yet been established, and the uniaxial test is generally applied owing to its similar deformation modes. However, the methods to avoid errors caused by external effects on the uniaxial tensile test should be modified in the stretchability test owing to different tensile directions and materials. We suggest optimization methods for the stretchability tests considering the differences in this study. Polydimethylsiloxane (PDMS), which is widely used as a stretchable substrate, was used for the specimen, and the specimen shape was adapted according to ASTM E8/E8M. Because the polymer specimen had a low strength, a single-cut method was used to minimize the surface notch. Pre-stretching was performed to prevent axial distortion when fixing the specimen to the grip. When applying these optimization methods to stretching tests, the possibility of preventing errors caused by external effects was experimentally confirmed. The notch minimization effect was confirmed through the fracture of the specimen, and the axial alignment effect was confirmed through Poisson’s ratio.