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This review draws a rather comprehensive picture of how Suzuki polycondensation was discovered in 1989 and how it was subsequently developed into the most powerful polymerization method for polyarylenes during the last 20 years. It combines insights into synthetic issues with classes of polymers prepared and touches upon aspects of this method's technological importance. Because a significant part of the developmental work was carried out in industry, the present review makes reference to an unusually large number of patents.

Oxygen permeabilities of nanocomposite films consisting of poly(methyl methacrylate) (PMMA) and different amounts of spherical zinc oxide (ZnO) nanoparticles were determined to investigate the barrier effect of this material with respect to particle content. A method was applied which is based on quenching of an excited phosphorescent dye by oxygen. Possible effects of the nanoparticles on the response of the dye molecules were investigated and were ruled out.

The proton conductivities of polyvinylbenzyl phosphonic acid PVBPA homopolymer and its statistical copolymers with 4vinyl pyridine polyVBPAstat4VPs are comprehensively studied in this work. Temperature and compositiondependent “dry” proton conductivities of the copolymers have been determined and the selfcondensation of phosphonic acid groups has been quantified. The results show that the intrinsic proton conductivities of polyVBPAstat4VPs and PVBPA are quite low at 150 °C and exhibit timedependent changes due to anhydride formation at elevated temperatures. The effect of polymer composition on proton conduction shows a minimum at a 1:1 molar ratio of proton donor and acceptor groups and is discussed on the basis of the pKavalues of the electrolyte species. A trace amount of water significantly increases conductivity probably due to additional hydronium ion diffusion and water bridging effects. Water content and proton conductivities of polyVBPAstat4VPs are determined at different relative humidities. High amounts of water are absorbed at high humidities leading to high proton conductivities.

Summary:Chain length dependence of the photoemission (fluorescence, phosphorescence, delayed fluorescence) and the respective life times of poly conjugated macromolecules is subject of controversy since long. An underlying question concerns coherence and extension/localization of the photoexcited states. Energy transfer within and between macromolecules as well as between sensitizers and macromolecules are relevant processes in systems to be used for displays or solar energy harvesting. In this context our recent work on photophysical characterization of pure oligo(fluorene)s and of the same oligomers containing just one fluorenone (“keto‐defect”) group is reviewed. Energy transfer between poly(fluorene)s and metal porphyrins is also covered. Triplet‐ triplet‐annihilation opens a route to efficient non‐coherent energy upconversion at ultralow excitation intensity (ca 1 Wcm−2). Light from the red region (635–700 nm) of terrestrial sun‐light is converted into the green region with ΔE ≥ 0.5 eV.

Amphiphilic diblock codendrimers consisting of dendrons of hydroxyl‐containing poly(methallyl dichloride) (PMDC) and long alkyl‐containing poly(urethane amide) (PUA) were synthesized in different generations. These codendrimers were found to self‐assemble into ribbonlike aggregates in organic solvent and further formed three‐dimensional networks and behaved macroscopically as gels. The width of the self‐assembled ribbons decreases with the generation of both dendritic blocks. Multiple intermolecular hydrogen bonds between amide and hydroxyl groups were found to be the main driving force to form these self‐assembled gels.

Oxygen permeabilities of different polymers were determined by using two different methods based on quenching of an excited phosphorescent dye by oxygen. In the first method, the phosphorescent dye platinum octaethylporphyrin is directly dissolved in the polymer film of interest whereas in the second method a sensor film is used which is separated from the film of interest by a spacer. The polymers investigated are PMMA, PVC, PVAc, cellulose acetate, PEMA, and PS. The resulting oxygen permeability coefficients are compared with data reported in the literature. It was found that oxygen permeation strongly depends on the protocol of preparation and thermal history of the films.