Stereoregularity of poly(1-butadienes) with aromatic substituents

Abstract

Poly[1,4-(1-phenylbutadiene)] and poly[1,4-(1-biphenylbutadiene)] polymerized anionically in THF had microstructure of 90.9%, 96.4% of 1,4, and 9.1%, 3.6% of 3,4, respectively as determined by 400㎒ $^1H$. However, poly[1,4-(1-naphthylbutadiene)] and poly[1,4-(1-phenanthrylbutadiene)] had complete 1,4 structure. The $^13C$ NMR spectra of the alternating copolymers of arylethylene and ethylene obtained by hydrogenation of poly[1,4-(1-arylbutadienes)] showed the fine structure that can be attributed to dyad or triad stereosequences. These spectra indicated that the alternating arylethylene-ethylene copolymers prepared from poly[1,4-(1-biphenylbutadiene)], poly[1,4-(1-naphthylbutadiene)] and poly[1,4-(1-phenanthrylbutadiene)] had the stereostructure slightly in favor of isotactic structures.