UCLA researchers have demonstrated a polymer light-emitting device with intrinsically stretchable properties.
Stretchable electronic materials are a class of modern electronic materials that have bending and stretching properties. They can be used in varied applications, such as minimally invasive type of biomedical devices, "smart skins", and wearable electronics. Currently used electronic devices are made of inorganic materials and are brittle in nature. When ultra-thin layers of inorganic materials are used, the electronic devices can be bent or stretched. These devices contain a discrete LED chip that is interconnected with electrodes that are stretchable. But all parts of these devices cannot be stretched.
Stretchable polymer LED
Researchers belonging to the UCLA Henry Samueli School of Engineering and Applied Science have now shown that a polymer light-emitting device has "intrinsic stretchability", in which all parts of the device are stretchable. For fabricating the transparent devices they used electrodes made of single-walled carbon nanotube polymer composites. They made the device by roll laminating two composite electrodes that have an emissive polymer layer sandwiched between them.
The surface layer of the composites, which is made of polymer matrix, and the interpenetrating nanotube networks lead to a sheet that has high transparency, low surface roughness, low sheet resistance and high compliance. Without affecting the resistance of the sheet, the composite electrodes can be stretched reversibly and the electronic devices can be stretched linearly by 45%.
The polymer light-emitting device with "intrinsic stretchability" is a milestone achievement in the development of stretchable electronics.