Combination of RAFT and Pd(II)-Initiated Isocyanide Polymerizations: A Versatile Method for Facile Synthesis of Helical Poly(phenyl isocyanide) Block and Star Copolymers

• Published in: Macromolecules Vol. 51; no. 3; pp. 737 - 745
• Main Authors: Jiang, Zhi-Qiang, Zhao, Song-Qing, Su, Yi-Xu, Liu, Na, Wu, Zong-Quan
• Format: Journal Article
• Language: English
• Published: American Chemical Society 13.02.2018
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/acs.macromol.7b02663

We report a new method for facile synthesis of block and star copolymers composed of helical poly­(phenyl isocyanide) and polyacrylate segments via combination of Pd­(II)-initiated isocyanide polymerization and reversible addition–fragmentation chain transfer (RAFT) controlled radical polymerization. First, an alkyne–Pd­(II) complex containing benzyl trithiocarbonate substituent was designed and synthesized. The Pd­(II) moiety of the complex can catalyzed the living polymerization of phenyl isocyanides, while the benzyl trithiocarbonate unit can be used as a chain transfer agent for RAFT polymerization. Upon combination of the two living polymerizations, a series of block copolymers containing poly­(phenyl isocyanide) and polyacrylate, poly­(aryl vinyl) blocks with expected molecular weights (M ns) and narrow molecular weight distributions (M w/M ns) can be facilely prepared under controlled manner. Some of these block copolymers exhibited interesting self-assembly and stimuli-responsive properties. Taking advantage of this synthetic approach, core cross-linked star block copolymer carrying polyacrylate-block-polyisocyanide arms can be readily prepared through the copolymerization with a cross-linker, ethylene glycol dimethacrylate. Moreover, miktoarm star copolymers carrying helical polyisocyanides and polyacrylates arms can also be prepared under controlled manner.