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Department of Engineering, ICT and Technologies for Energy and Transport Patent Title Conductive polymer sponge for integrated sensors. Ref. CNR 10425 Assignee (s): CNR CNR Institute: IMEM Main inventor: Nicola Coppedè Countries: IT, PCT Priority date: 22/12/2015 Abstract The invention is directed towards the field of sensors made of commercial materials that allow you to make active otherwise passive materials (smart materials, active materials, internet of things) without changing the structure and functionality of them. The invention relates to the functionalization process of an elastic porous material, such as sponge, with a conductive polymer, which adheres to the inner walls of the structure, making it electrically active, and then allowing the realization of integrated pressure sensors in industrial materials, such as insoles, mattresses , pillows, floors. The operational principle is based on increasing the current passing through the material following the increase of pressure and of the inner contact of the parts. With these conductive materials it is also possible to realize organic electrochemical sensors integrated directly in industrial materials, useful for the analysis of fluids. Background Active materials that transform inert products into smart objects, able to become sensitive due to suitably integrated sensors, are assuming an increasingly applicative interest. This is possible by making functional the same material through nanotechnologies and smart materials. These devices must, of course, be convenient, low cost, durable and stable. For pressure sensors, attempts at functionalization have been made with graphene, however, such material still continues to have a high cost and a lack of continuity of the structure itself. Technology The technology is based on the use of conductive organic polymers, conveniently prepared in an aqueous solution and deposited on the porous material for absorption. Following treatment, the polymer forms a thin film of about 200 nm, which covers each inner part of the porous material, making it to all effects conductive. Thanks to the pressure, the sides of the pores collapse on one another, proportionally increasing the conduction. Advantages and Applications Make active an inert material, in a simple and direct, way, in order to form a sensitive structure that is able to respond to the environment. From the industrial point of view, the ability not to change the use of common materials, but simply render them functional , allows the realization of a sensor at low cost and scalable to the industrial process, without varying the structural characteristics. Development stage The functional material has been made on different types of porous polymer and has been shown to make the structure conductive. Pressure sensors have been realized on an orthopedic insole, in order to measure the posture during walking. An electrochemical sensor has been made that is capable of absorbing fluids and 53 analyzing the content of salts and other organic components (Adrenaline, Dopamine).