A highly easy and efficient metal-free methodology for the synthesis of polyaziridine-based polymers with controlled architectures and desired functionalities was developed by organocatalytic ring-opening polymerization (ROP) of N-sulfonyl aziridines with a carboxylic acid as initiator. 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (MTBD) and phosphazene t-Bu-P4 organocatalysts have demonstrated high catalytic efficiency in connection with the controlled/living character of the ROP of 2-methyl-N-tosylaziridines (TsMAz) initiated by benzoic acid. Aryl carboxylic acids bearing an azido or a hydroxyl group as well as bio-derived vanillic acid and syringic acid and alkyl- and alkenyl-substituted carboxylic acids, such as acetic acid, palmitic acid, and methacrylic acid, can all initiate the ROP of TsMAz toward well-defined P(TsMAz)s. α,ω-Diamino telechelic, star-shaped P(TsMAz)s, and poly(styrene-co-methacrylic acid)-graft-poly(2-methyl-N-tosylaziridine) [P(St-co-MAA)-g-P(TsMAz)] have been conveniently synthesized from the corresponding multicarboxyl (macro)initiators. Finally, this protocol has been applied for the synthesis of a linear photoresponsive P(TsMAz) and an aggregation-induced emission (AIE)-active 4-arm P(TsMAz) star from the corresponding functionalized carboxylic acids.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This work is financially supported by the National Natural Science Foundation of China (21801049) and the start-up funding of Guangdong University of Technology (220413206 and 220418129). N.H. acknowledges the support of King Abdullah University of Science and Technology. The authors thank Prof. Hefeng Zhang at Shantou University for his help in SEC-MALS measurement.