Michael Monkenbusch

On Structure and Properties of Polypyrrole Alkyl-Sulf(on)Ates

Abstract Tenside anion “doped”, highly conducting polypyrroles (PPY) have been grown electrochemical-ly from aqueous electrolytes. The influence of the electrolysis parameters on the conductivity have been investigated. The X-ray diffraction patterns allow to derive a structural model.

Radical Cation Salts of Arenes. Structure, Properties and Model Character for Conducting Polymers

Abstract Radical cation salts of arenes are obtained by anodic oxidation. They are a new family of organic conductors. Common structural principles are reviewed. Radical cation salts of oligomers of poly-p-phenylene have been prepared and characterized. The packing found in these model compounds can be used to construct models for conducting polymers.

New Routes to Conducting Polymers and New Insights into Structure-Properties Relations

Abstract The structure of conducting polymers is discussed in comparison to simple, so-called organic metals derived from naphthalene and similar arenes. In this context the conducting polymers are viewed as ion-radical salts of the backbone-units. This view is substantiated by recent results from X-ray investigations on electrochemically oxidized p-quaterphenyl as a model for poly(p-phenylene), poly-pyrrol salts of detergent ions and oxidized, highly oriented polyacetylene.

Structure of Doped Polymers

Abstract Studies of the synthesis, molecular weight, structure and morphology of polyacetylene (PA) indicate that the average length of linar chain segments between structural defects like crosslinks and chain folds is of the order of 20 units. Several models for the crystal structure of trans PA are given. The influence of the morphology on the mechanism of charge tranport is discussed. The doping is found to be inhomogeneous and the macroscopic conductivity is controlled by the topology of interlamellar contracts.

On the packing properties of poly(acetylene) chains

Packing calculations relevant to the crystal structure of trans-poly(acetylene) are described. Three classes of chain arrangements have been studied: pseudomonoclinic structures with one chain per unit cell and orthorhombic and monoclinic structures containing two symmetry related chains. The results are compared with experimental data on trans-poly(acetylene) reported in the literature and structure analyses of octatriene(2,4,6)-acid and 1,10-dicyanooctatetraene(1,3,5,7) which are reported as well. The same packing program has been used to recalculate the structure of cis-poly(acetylene). The results indicate the possibility for polymorphism in poly(acetylene) because several packing modes can be derived which differ very little with regard to their packing energy. However, literature data on the assignment of lattice parameters from poorly resolved X-ray, electron and neutron diffraction data can now be critically discussed.

Morphology of Pristine Poly (Acetylene) Obtained by Luttinger's Catalyst

Abstract Poly (acetylene) was jprepared as freestanding mechanically stable film using Luttingers catalyst. The cis isomer formed initially is stable during storage at room temperature over many days. Electron micrographs show a loose conglomerate of irregularly shaped platelets with a diamjeter of several ten nanometers and a thickness of less than 10 nm. Electron diffraction on the cis form shows the chain axes perpendicular to the lamella surface. Annealing conver ts the polymer into the trans isomer. Morphological changes are not observed. The chanins however tilt in the course of the phase transition associated with the isomerization. Films of the material obtained by Luttingers cataltyst show essentially the same electrical and mechanical behavior as the ones prepared by a Shirakwa-technique.