Catalyst-free and visible light-induced RAFT alternating polymerization of 1,3-pentadiene isomers and maleic anhydride

• Published in: European polymer journal Vol. 196; p. 112292
• Main Authors: Liu, Kun, Xiong, Qiaoqiao, Gu, Zhuowei, Zhang, Feng, Fu, Yawen, Xie, Fengli, Yi, Wenjun, Li, An, Xu, Jundong, Li, Lijun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 11.09.2023
• Subjects: 1,3-Pentadiene isomers; Alternating photopolymerization; Reversible addition-fragmentation chain transfer polymerization; Visible light-mediated photoinduced; 1,3-Pentadiene isomers; Reversible addition-fragmentation chain transfer polymerization; Visible light-mediated photoinduced; Alternating photopolymerization
• ISSN: 0014-3057; 1873-1945
• DOI: 10.1016/j.eurpolymj.2023.112292

[Display omitted] •Visible-light mediated photoinduced-RAFT copolymerization of 1,3-pentadiene isomers (TP, CP and PD) and maleic anhydride (MAH) in the absence of photocatalysts or photoinitiators has been realized in THF solvent at r.t. under various visible wavelengths.•both TP and PD isomers can be copolymerized with MAH to afford alternating copolymer with high yields up to 100%, even the photo-polymerization rates listed in the order: PD > CP > TP. And the copolymerization can be implemented by simply switching the light source ON/OFF.•We supposed that the donor–acceptor interaction between the PD and MAH (similar with St/MAH system) played an important role in this novel light-induced RAFT alternating coplymerization behavior. Visible light-mediated photoinduced reversible addition-fragmentation chain transfer polymerization (RAFT) copolymerization of 1,3-pentadiene isomers and maleic anhydride (MAH) in the absence of photocatalysts or photoinitiators was realized in tetrahydrofuran (THF) solvent at r.t. under various visible wavelengths. The well-defined alternating copolymers were successfully and efficiently synthesized by directly using O-ethyl-S-benzoic thioanhydride (EBT) as chain transfer agent activated by blue light (460 nm). The conventional thermal-initiated radical copolymerization of 1,3-pentadiene (PD) isomers (except cis-1,3-pentadiene (CP)) and MAH gave both DA cycloaddition products and alternating sequence copolymers. In contrast, the alternating copolymer was the only isolated product in this photoinitiated polymerization system, in which the DA reaction was completely suppressed. Moreover, both trans-1,3-pentadiene (TP) and PD isomers can be copolymerized with MAH to give alternating copolymers with high yields up to 100%, although the photopolymerization rates are in the order: PD > CP > TP. And the copolymerization can be implemented by simply switching the light source ON/OFF. We supposed that the donor–acceptor interaction between the PD and MAH (similar to St (styrene)/MAH system) plays an important role in this novel light-induced RAFT alternating copolymerization behavior.