New Insights into the Microstructure of GILCH-Polymerized PPVs

The microstructure of GILCH-polymerized PPVs was examined by NMR techniques. Selectively main-chain 13C-labeled polymers were prepared and investigated by 1H NMR, 13C NMR, and 2D NMR methods. Only one major polymerization defect was discovered:  tolane−bisbenzyl (TBB) moieties could be proven in amounts of 1.5−2.2% for OC1C10−PPV. Furthermore, indications for ether-type end groups (∼0.2%) were found. These defects are readily explained by the polymerization mechanism. Other structural elements (e.g., cis double bonds, branching) were not detected.