The development of the industrial implementation of large-area printed electronics depends, among other things, on a sufficiently flexible source of key materials for both sensor and circuit structures. The market offering metallic printing formulations or materials based on conductive metal oxides is largely filled, whereas, in the field of organic conductive and semi-conductive materials, the offer is still in development.
Although several very interesting products have already been proposed within the research activities, it must be borne in mind that the transfer of the synthesis of these materials into a process of proper production with a pilot or operational scale is a time-consuming and financially demanding process.
Within the MADRAS project, conductive materials based on PEDOT are proposed for conductive electrode layers and charge transfer layer (HTL), including its hybrid combinations with inorganic materials. Successful laboratory experiments are currently being transferred to the scale of a glass pilot plant.
Within the synthesis of organic materials, there are large differences between processes suitable for small laboratory scale and the scale of a glass pilot plant, which is closer to real industrial conditions. Within the upscaling, it is necessary to keep in mind the changes of physicochemical parameters of syntheses. These are mainly the mixing conditions, the thermal annealing of the reaction mixture and the conditions for the isolation of the product.
Figure 1. Pilot plant evaporator for isolation of organic materials from organic solvents during purification and isolation process
The Center for Organic Chemistry (COC) is currently optimising synthetic processes, focusing primarily on hybrid systems where PEDOT is bound to inorganic carriers. The aim of this optimisation is the gradual conversion of synthesis from larger laboratory scales, which allow synthesis in the volume of the reaction mixture, up to 6 L to glass pilot scale, in which COC has apparatus with a volume of 15 to 100 L. The process can then be transferred to a real pilot scale equipped with stainless steel and enamelled apparatus with a volume of 600 L.
Figure 2. Glass pilot plant apparatus (100 L) for tests of synthetic procedures
The issue of product purification and recycling of used solvents is also related to the process of upscaling synthesis. For that matter, COC is equipped with standard purification procedures, including a pilot plant for column chromatography and pilot plant rotary evaporators.
The aim of the MADRAS project is to set up the entire production process, including the design of the production of starting materials in reliable printing form, intended for printing on flexible substrates. COC aims to design such a technology, which will also enable the production of new materials for the entire field of organic and large-area electronics (OLAE).
About the author
Dr.Lubomir Kubac, Executive Head of COC since 2009
- Long-term experience in the field of industrial research and design of new technologies
- Expert experience in the field of new functional modifications of conductive polymers and their fixation on solid carriers modified as dopants of conductive polymers
- Experience in the field of research project management and subsequent transfer of research results to the industrial scale
- Design of realizations of functional colorants
- More than 20 technologies implemented on an operational and pilot scale
COC is an industrial research organization that provides a wide range of services in the transfer of new innovative knowledge to the industrial sphere. As part of research projects funded within the EU, by the national government or private entities, it provides research into new materials in the field of printed and flexible electronics, photoactive materials, materials for battery construction and functional coatings. The company is fully equipped for the optimization of synthetic procedures in laboratory conditions and their subsequent verification in the conditions of glass and reguler pilot plant. At the same time, it has the necessary background for the analytical characterization of synthetic processes and the purity of the resulting products. As part of the service provided, COC is able to ensure cooperation in the transfer of technology to an industrial scale by being able to ensure low-tonnage production of products during the product marketing stage. Subsequently, a final technological regulation suitable for the operating conditions of the final industrial implementer is developed.
In addition, COC is developing applications for its own materials, in particular hybrid conductive materials modified with conductive polymers and photoactive organic substances capable of generating reactive oxygen species based on organic colorants. COC has long been dedicated to the application of functional materials and the possibility of their fixation in a polymer matrix so as to prevent their migration and at the same time preserve their functional properties.
