The polymerization of styrene catalyzed by n-butyllithium in the presence of carbon black

✍ Scribed by Kumakazu Ohkita; Naoki Nakayama; Masato Shimomura

• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 383 KB
• Volume: 18
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(80)90051-2

✦ Synopsis

The polymerization of styrene catalyzed by n-butyllithium has been carried out in the presence of carbon black at 0°C in toluene. A large portion of the catalyst was consumed by the reaction with the carbon black surface and thus the growth of polystyrene anions on the surface was hindered to a considerable extent. The typical retardation of conversion of styrene monomer to polymer does not change even in the presence of carbon black pretreated with sodium borohydride solution. The intrinsic viscosities of the homopolymers formed in the presence of carbon black were found to be higher than those of the ones formed in the absence of carbon black. On the other hand, the addition of carbon black during the anionic polymerization of styrene was found to promote grafting the growing polymer anions onto the surface of carbon black, consequently giving polymer-grafted particles, while hindering the conversion of styrene into polymer. However, little grafting was observed when the carbon black pretreated with sodium borohydride solution was used. The phenomena indicate that quinonic groups present on the surface of carbon black may be responsible for the capture of growing polymer anions.