Fabrication and characteristics of elastic siloxane hybrid materials for application on stretchable device

Abstract

With the advent of foldable devices in the market starting with foldable phones, the development of materials for them has also become indispensable. Unlike the flat devices, foldable devices could be easily damaged due to repetitive deformation, so it is essential to develop elastic materials with deformability. Among them, in foldable device structure, a large stress is applied to the cover window film present on the outermost part of the device under deformation. Therefore, the materials for the cover window are required to have elasticity to prevent the fracture came from the stress. In addition, since the cover window is a boundary that divides the inside and outside of the device, it is easily exposed to the external environment, and thus, it must have the capability to protect the inside from the outside. Therefore, it is necessary to develop a new material that can stretch elastically and protect the device from external harmful elements (e.g. scratch, UV irradiation). Recently, not only the method of imparting flexibility to rigid bulk materials through downscaling, but also the method of rendering flexibility to materials through nanomaterials or polymeric materials has attracted large interest. In this study, new siloxane hybrid materials that protects the device with rigidity and has stability against deformation with intrinsic flexibility were developed by hybridizing polymer materials with excellent flexibility such as PDMS or polyurethane at the molecular level with siloxane molecules having a rigid network. The newly developed elastic siloxane hybrid materials were confirmed for its applicability as a cover window film by various analyses. Furthermore, owing to its intrinsic elasticity properties, the newly developed elastic siloxane hybrid materials are expected to be applicable not only for cover windows, but also in various fields requiring elasticity.