No abstract

The main goals of the present work are the production of bifunctional initiators through reactions between n‐butyl lithium (n‐BuLi) and divinylbenzene (DVB) and evaluation of the initiator performance in styrene polymerizations. Bifunctional initiators are desired for production of elastomers because they can be used to produce telechelic polymers. Initiators were prepared in solution in presence of the polar modifier 2,2‐ditetrahydrofurylpropane (DTHFP), used for solvation of the lithium cation and increase of the ion solubility in aliphatic hydrocarbons. It is shown that useful multifunctional initiators can be produced at the analyzed conditions, as indicated by the high average molar masses of the final product.

Multifunctional anionic initiators based on n‐BuLi and the diolefin m‐DIB (meta‐diisopropenylbenzene) were synthesized and stored at different temperatures, using different polar modifier contents and solvents. Solution styrene polymerizations were then used to evaluate the performances of the produced initiators. Based on the obtained results, it is shown that the best initiators were the ones prepared at 40 °C, using the DTHFP/BuLi molar feed ratio of 0.1 in cyclohexane. At these preparation conditions, the produced initiator has higher contents of multifunctional species and presents higher stability. The DTHFP/n‐BuLi ratio of 0.1 was shown to be the most appropriate because it minimizes the formation of oligomers and allows for suitable initiation of styrene polymerizations.