Polyacetylene cyclooctatetraene with tungsten

The third route involves metathesis polymerization of cyclooctatetraene with tungsten catalysts, yielding polyacetylene as an insoluble film along with oligomers (iOi). By first polymerizing cyclooctene and then adding cyclooctatetraene, a soluble, red block copolymer was obtained. On the basis of the visible absorption spectrum, at least two or three cyclooctatetraene units were concluded to have been added to the polymer chain forming a short polyacetylene block. No conductivity data were reported for this copolymer. 

Possibly the most convenient direct route to polyacetylene, namely the polymerisation of cyclooctatetraene (COT), was introduced by Grubbs and co-workers [4], They initially showed that polyacetylene can be obtained via ROMP of COT using the very active Schrock type tungsten hexafluoro-t-butoxide initiator W(=CHR)(OC(Cp3)2 CH3 )2(=NAr). A freestanding film was obtained when the monomer was polymerised as the neat liquid. A random copolymer was obtained from the polymerisation of a mixture of COT and 1,5-cyclooctadiene (COD) and, as expected, a gradation in colour and Raman shift showed that the conjugation length of the polyene sequences increased with COT... 

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