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In this work, we have studied the uniaxial tension behaviors of the silicone-carbon nanotube (CNT) laminated structure (SCLS) with the load capacity of the CNT film comparable to that of silicone rubber, based on which a theoretical model is proposed to explore the underlying mechanism. The uniaxial tension behaviors of SCLS can be clearly divided into three stages corresponding to the uniform deformation of silicone rubber and CNT film, continuous fracture of CNT film, and uniaxial tension of silicone rubber, respectively. A zigzag plateau stress is observed in stage II. Indeed, the CNT film can act as a pinning ligament to constrain the deformation of silicone rubber, while its continuous fracture can gradually release the deformability of silicone rubber which is beneficial to increase the toughness of SCLS. By considering the in-plane tension stress of the CNT film and interface shear stress transfer, a continuous fracture and pinning model is proposed which can describe the uniaxial tension behaviors of SCLS very well. The results presented herein may shed useful insights for the design and optimization of the film-substrate based stretchable electronics. [ABSTRACT FROM AUTHOR]

In this work, the surface wrinkle modulation mechanism of the three-dimensional (3D) film/substrate system caused by biaxial eigenstrains in the films is studied. A theoretical model based on the energy minimization of the 3D wrinkled film/substrate system is proposed which shows that the change of the surface wrinkle amplitude is determined by four dimensionless parameters, i.e., the eigenstrain in the film, plane strain modulus ratio between the film and substrate, film thickness to wrinkle wavelength ratio, and initial wrinkle amplitude to wavelength ratio. The surface wrinkle amplitude decreases (even almost flat) upon contraction eigenstrain in the film, while increases for that of expansion eigenstrain. Parallel finite element method (FEM) simulations are carried out which have good agreements with the theoretical predictions, and experimental verifications are also presented to verify the findings. Besides, different patterns of 3D surface wrinkles are studied and the similar surface wrinkle modulation is also observed. The findings presented herein may shed useful insights for the design of complex stretchable electronics, cosmetic products, soft devices and the fabrication of 3D complex structures. [ABSTRACT FROM AUTHOR]

In this work, the surface wrinkle modulation of the film/substrate system caused by eigenstrain in the film is studied. A theoretical model is proposed which shows the change of the wrinkle amplitude is completely determined by four dimensionless parameters, i.e., the eigenstrain in the film, the plane strain modulus ratio between the film and the substrate, the film thickness to wrinkle wavelength ratio, and the initial wrinkle amplitude to wavelength ratio. The surface wrinkle amplitude becomes smaller (even almost flat) for the contraction eigenstrain in the film, while for the expansion eigenstrain it becomes larger. If the expansion eigenstrain exceeds a critical value, secondary wrinkling on top of the existing one is observed for some cases. In general, the deformation diagram of the wrinkled film/substrate system can be divided into three regions, i.e., the change of surface wrinkle amplitude, the irregular wrinkling, and the secondary wrinkling, governed by the four parameters above. Parallel finite element method (FEM) simulations are carried out which have good agreement with the theoretical predictions. The findings may be useful to guide the design and performance of stretchable electronics, cosmetic products, biomedical engineering, soft materials, and devices. [ABSTRACT FROM AUTHOR]