Surface functionalization of porous polymer networks was investigated using the sulfonation of macroporous styrene-divinylbenzene (S-DVB) copolymers as model reaction. Reaction conditions for the surface sulfonation were studied. Sulfonation with sulfuric acid in the presence of nitromethane was found to be a suitable method. Models and ideas of network structure are developed in order to estimate surface capacities and to show that surface-sulfonated networks were obtained. ZUSAMMENFASSUNG:Die Oberflachenfunktionalisierung polymerer Netzwerke wurde anhand der Sulfonierung makroporoser Styrol-Divinylbenzol-Copolymerer (S-DVB) als Modellreaktion untersucht. Die Bedingungen fur eine Oberflachensulfonierung wurden untersucht. Es wurde gefunden, daB die Sulfonierung mit Schwefelsaure in Gegenwart von Nitromethan eine geeignete Methode ist. Modelle und Vorstellungen uber die Struktur der Netzwerke werden entwickelt, um Oberflachenkapazitaten abzuschatzen und um zu zeigen, daB oberflachensulfonierte Netzwerke erhalten wurden.

We present numerical studies of localization properties of oxidized and protonated disordered polyaniline. The calculations are performed on the single electron level, using Hiickel theory for~electrons. The spatial extension of the eigenstates at the Fermi energy is determined by a fast and accurate transfer-matrix scheme. The spatial extension of eigenstates diverges for a large degree of protonation, provided all bonds within the benzoid and quinoid can be described with the same set of tight-binding parameters. Localization effects become important for small degrees of protonation and in systems that show bond-length alternation in quinoid rings and aromatic bonds in benzoid rings.

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