D. Lynch, U. Geissler, K. Byriel
Oct 22, 2001
Citations
1
Influential Citations
22
Citations
Journal
Synthetic Metals
Abstract
Abstract The polysquaraines of six oligo(1-methylpyrrole)s have been synthesised and studied for electrical conduction properties. The oligomers used include 1-methylpyrrole itself, the dimer, the trimer, the tetramer, the hexamer and a mixture of 6–12 1-methylpyrrole units long. The X-ray crystal structures of the trimer and tetramer are reported and provide a valuable insight into the potential packing of their polysquaraine analogues. Of the series, only the tetramer polysquaraine (Sq.Py 4 ) conducts (2×10 −7 S cm −1 ) whereas the first three members are essentially insulators with dielectric breakdown values of 1–0.05 MV cm −1 . The X-ray powder diffraction analysis of Sq.Py 4 indicates that this polymer has one-dimensional order with a close interlayer spacing of 3.4 A, which compares to 3.6–3.8 A in several of the other polymers. This close packing is also evident by the red–purple colouration of Sq.Py 4 while the other polymers are dark blue. The results indicate that a consideration of the solid-state packing of polysquaraines is required before these materials will exhibit some of their predicted electrical conduction properties.