Ladder blends

Recommendations on additional aspects of macromolecular nomenclature such as that of regular double-strand (ladder and spiro) and irregular single-strand organic polymers continue to be pubHshed in I ure and Applied Chemistty (100,101). Recommendations on naming nonlinear polymers and polymer assembHes (networks, blends, complexes, etc) are expected to be issued in the near future. 

E.J.W. List, L. Holzer, S. Tasch, G. Leising, M. Catellani, and S. Luzzati, Efficient, single layer yellow light emitting diodes made of a blend of a ladder-type poly(p-phenylene) and polyalkylthio-phene, Opt. Mater., 12 311-314, 1999. 

Fig. 29.14 Electroluminescence spectra for the ladder polyphenylene of the type shown in Fig. 29.4, with Ri = C6H4-C10H21, R2 = C6H13, and = H. The ladder polymer is diluted with polystyrene, so the weight fraction of the ladder polymer is (a) 30%. (b) 10%, and (c) 1%. Note that blend (a) shows yellow emission and blend (c) shows substantially blue emission. (From Ref. 66.)...

The polymers highlighted in this chapter include those based on polyazoles, polybenzazoles, aromatic polyimides, and a variety of ladder and semi-ladder polymers. The key synthetic strategies to produce these polymers as well as detailed assessment of various synthetic strategies are described in detail. Molecular composites, in which molecular-level blends of rigid rod polymers are produced to enhance strength, are described. 

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