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Title: Tandem Living Insertion and Controlled Radical Polymerization for Polyolefin–Polyvinyl Block Copolymers
Abstract

Practical synthesis of polyolefin–polyvinyl block copolymers remains a challenge for transition‐metal catalyzed polymerizations. Common approaches functionalize polyolefins for post‐radical polymerization via insertion methods, yet sacrifice the livingness of the olefin polymerization. This work identifies an orthogonal radical/spin coupling technique which affords tandem living insertion and controlled radical polymerization. The broad tolerance of this coupling technique has been demonstrated for diverse radical/spin traps such as 2,2,5‐trimethyl‐4‐phenyl‐3‐azahexane‐3‐nitroxide (TIPNO), 1‐oxyl‐(2,2,6,6‐tetramethylpiperidine) ‐4‐yl‐α‐bromoisobutyrate (TEMPO‐Br), andN‐tert‐butyl‐α‐phenylnitrone (PBN). Subsequent controlled radical polymerization is demonstrated with nitroxide‐mediated polymerization (NMP) and atom transfer radical polymerization (ATRP), yielding polyolefin–polyvinyl di‐ and triblock copolymers (Đ<1.3) with acrylic, vinylic and styrenic segments. These findings highlight radical trapping as an approach to expand the scope of polyolefin‐functionalization techniques to access polyolefin macroinitiators.

 
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NSF-PAR ID:
10364167
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
134
Issue:
10
ISSN:
0044-8249
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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