produced the carbazole based methacrylates, which were then polymerized in toluene with AIBN (Scheme 2.2). Molecular weights obtained using this method were low, with broad polydispersities. The reason was attributed to low solubility of the polymers in toluene. The polymerization was performed in more polar solvents, such as tetrahydrofuran (THF) and 1,4-dioxane, but still, only low molecular weight, oligomeric products were obtained. The reason was attributed to chain transfer with the solvent.233
The second method used by Strohriegl was successful in producing high molecular weight polymethacrylates with pendant carbazole groups. In the second method, the hydroxyalkylcarbazoles were reacted with butyllithium to form the corresponding alcoholates, which were then reacted with poly(methacryloyl chloride) in the solvent THF (Scheme 2.2). This method produced polymers with number average molecular weights of 50,000 g/mole or higher. The degree of substitution was at least 95 % for the entire series of carbazole based polymethacrylates. High quality films suitable for photoconductivity experiments were cast from these carbazole based polymethacrylates.234
Strohriegl, P. Makrol. Chem., 1993, 194, 393. Strohriegl, P. ibid.