The Copolymer Approach to Controlled Light Emission in Polymers

2 The Copolymer Approach to Controlled Light Emission in Polymers 

We have studied two types of polymers that both belong to the second case those in which luminescent chromophores (typically Ti-conjugated oligomers) are separated by higher-energy-gap blocks (see Fig. 16-1 a) and those in which the chromophores are linked to each other in a non-coplanar way (see Fig. 16-1 b). 

3 Oligomers as Model Compounds for Structure-Property Studies 

These model compounds can also be used in device fabrication, since thin films of appropriate diickness can be obtained by sublimation and subsequent deposition onto a substrate in vacuum. Electrical as well as optical properties of such devices have turned out to be strongly dependent on both the molecular packing within the crystallites and the polycrystalline morphology. Understanding and control of this aspect is one of the current scientific challenges. 

Oligo(l,4-phenylene vinylene)s are in principle accessible via a large variety of methods [39]. However, out of this large number of methods, the use of only a small number has actually been reported. The most extensively used method is 

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