Abstract
The controlled anionic ring-opening polymerization of hexamethylcyclotrisiloxane (D3) was optimized for a commercial and easy-to-use organic catalyst, 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), employing various types of initiators. Alcohols and silanols were compared for the synthesis of monofunctional and telechelic PDMS. Polymerizations were monitored by 1H NMR spectroscopy, MALDI-TOF mass spectroscopy and SEC to compare the effects of the initiator structure and catalyst concentration. TBD was shown to control the AROP of D3 when using silanols as the initiator, thus affording well-defined PDMS structures. When alcohols were used as initiators, the polymerization proceeded with a lower level of control due to slower initiation. These differences in initiation rates likely originated from the differences in pKa between silanols and alcohols.