A versatile approach for the preparation of end‐functional polymers and block copolymers by stable radical exchange reactions. Issue 24 (8th May 2019)

• Record Type: Journal Article
• Authors: Goksu, Yonca Alkan; Yilmaz, Gorkem; Yagci, Yusuf
• Is Part Of: Journal of polymer science. Volume 57:Issue 24(2019)
• Page Start: 2387
• Page End: 2395
• Publication Date: 2019-05-08
• Subjects: block copolymer -- nitroxide mediated radical polymerization -- radical coupling -- stable radical -- telechelic polymer; 547
• DOI: 10.1002/pola.29400
• Languages: English
• ISSNs: 0887-624X

Abstract

ABSTRACT: A versatile strategy for the preparation of end‐functional polymers and block copolymers by radical exchange reactions is described. For this purpose, first polystyrene with 2, 2, 6, 6‐tetramethylpiperidine‐1‐oxyl end group (PS‐TEMPO) is prepared by nitroxide‐mediated radical polymerization (NMRP). In the subsequent step, these polymers are heated to 130 °C in the presence of independently prepared TEMPO derivatives bearing hydroxyl, azide and carboxylic acid functionalities, and polymers such as poly(ethylene glycol) (TEMPO‐PEG) and poly(ε‐caprolactone) (TEMPO‐PCL). Due to the simultaneous radical generation and reversible termination of the polymer radical, TEMPO moiety on polystyrene is replaced to form the corresponding end‐functional polymers and block copolymers. The intermediates and final polymers are characterized by 1 H NMR, UV, IR, and GPC measurements. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2387–2395 Abstract : Synthesis of block copolymers with well‐designed architectures is of special interest since intermediary properties in between main segments could be obtained. In the frame of ongoing interest in the development of synthetic routes for the preparation of well‐defined macromolecular architectures, the authors report a simple and versatile methodology for telechelic and block copolymer formation by stable radical exchange reactions.