SYNTHESIS AND MATERIAL PROPERTIES OF SOLUBLE POLY(1,1'-FERROCENYLENE-ALT-P-OLIGOPHENYLENES)

A series of poly(1,1'-ferrocenylene-alt-p-oligophenylenes) has been pr epared via Pd-catalysed polycondensation, i.e. poly(1,1'-ferrocenylene -alt-p-terphenyl-4,4 ''-ylene), poly(1,1'-ferracenylene-alt-p-quinquep henyl-4, 4 ''''-ylene), and poly(1,1'-ferrocenylene-alt-p-septiphenyl- 4,4 ''''''-ylene), which bear two solubilising n-hexyl or n-dodecyl si de chains at every repeating unit. The homogeneous constitution of all soluble polymers has been proved using high-resolution H-1 and C-13 n .m.r. spectroscopy, and the degrees of polymerization have been shown to vary from P-n = 15 to 55. The material properties of the poly(1,1'- ferrocenylene-alt-p-oligophenylenes) have been analysed in bulk and so lution using t.g.a., d.s.c., WAXS, g.p.c., viscosimetry and light scat tering. Some of the results are contrasted with those of measurements on poly(p-phenylene) and poly[2,9-(o-phenanthroline)-alt-p-oligophenyl ene] reference polymers showing that the main chains of the poly(1,1'- ferrocenylene-alt-p-oligophenylenes) are by no means rodlike, like tho se of the poly(p-phenylenes) but assume randomly coiled conformations. However, the coils are less densely packed and significantly more fle xible than those of the poly [2,9-(o-phenanthroline)-alt-p-oligophenyl enes]. (C) 1998 Published by Elsevier Science Ltd. All rights reserved .