Anionic Polymerization of 4-Diphenylaminostyrene: Characteristics of the Alkyllithium/N,N,N′,N′-Tetramethylethylenediamine System for Living Anionic Polymerization

• Published in: Macromolecules Vol. 41; no. 11; pp. 3852 - 3858
• Main Authors: Natori, Itaru, Natori, Shizue, Usui, Hiroaki, Sato, Hisaya
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 10.06.2008
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polymerization; Preparation, kinetics, thermodynamics, mechanism and catalysts; Solvent effect; Priming activity; Living polymer; Experimental study; Syndiotactic polymer; Functional polymer; Solution polymerization; Styrene derivative polymer; Diamine; Lithium Organic compounds; Amine polymer; Preparation; Tertiary amine; Anionic polymerization; Stereospecific polymerization
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/ma800222z

A well-controlled anionic polymerization of 4-diphenylaminostyrene (DAS) with alkyllithium (RLi) has been achieved for the first time. The nucleophilicity and solubility of RLi, 4-diphenylaminostyryllithium (DASLi), and poly(4-diphenylaminostyryl)lithium (PDASLi) were very important controlling factors. An initiator system of tert-butyllithium (t-BuLi)/N,N,N′,N′-tetramethylethylenediamine (TMEDA) in toluene was found to be very effective. In this system, the t-BuLi/TMEDA complex reacts with toluene to form the benzyllithium (BzLi)/TMEDA complex, and this complex initiates the anionic polymerization of DAS. The DASLi/TMEDA and PDASLi/TMEDA complexes have sufficient nucleophilicity and stability as propagating species, without the metalation of toluene, and as a result, living anionic polymerization was achieved. The high molecular weight poly(4-diphenylaminostyrene) (PDAS), synthesized using the RLi/TMEDA system, had a syndiotactic-rich configuration, independent of the polymerization solvent.