Stability of OLEDs Using LMMMs

The temporal stability of OLEDs using low-molar-mass organic compounds 

The use of insoluble, highly cross-linked anisotropic networks created by the polymerisation of photoreactive monomers, eliminates the problem of crystallisation, at least for organic materials, since polymer networks are macromole-cular structures incapable of crystallising, see Chapter 6. Furthermore, the fabrication of multilayer devices would be facilitated by the use of a cross-linked stable HTL next to the anode on the solid substrate surface, onto which subsequent layers can be deposited by vapour deposition. Multilayer OLEDs are intrinsically more stable than monolayer devices due to a better balance of charge-carriers and concentration of the charged species away from the electrodes. The synthesis and cross-linking of a suitable aromatic triarylamine derivative with a polymerisable oxetane group at each end of the molecule for use as a HTL has been reported recently,  

An additional advantage of the use of reactive, photopolymerisable liquid crystalline monomers with charge transfer or electroluminescent properties is the ability to generate circularly and linearly polarised light. This possibility 

Miyata and H. S. Nalwa, in Organic Electroluminescent Materials and Devices Gordon and Breach, New York, USA, 1997. 

Kalinowski, J. Godlewski and Z. Dreger, Appl. Phys. Lett. A., 1985,37,179. 

---