Zwitterionic Alternating Polymerization to Generate Semicrystalline and Recyclable Cyclic Polythiourethanes. uri icon

abstract

  • Synthesis of cyclic, semicrystalline, and recyclable polythiourethanes was realized via the catalyst-free zwitterionic alternating copolymerization of N-alkyl aziridines with carbonyl sulfide (COS) under mild conditions. The copolymerization proceeded efficiently at room temperature and generated copolymers with fully alternating linkages in more than 99% selectivity in 5 min under solvent-free conditions. Notably, the copolymers are typical semicrystalline thermoplastics with melting temperatures up to 137 C (n-butyl-substituted) or 170 C (ethyl-substituted). The resulting polythiourethanes are predominantly cyclic as evidenced by 1H NMR and MALDI-TOF mass spectroscopies. Remarkably, the cyclic copolymers could be recycled into N-substituted cyclic thiourethanes in quantitative yield by heating at 250 C for 2 h.

published proceedings

  • ACS Macro Lett

author list (cited authors)

  • Tan, D., Hu, X., Cao, Z., Luo, M., & Darensbourg, D. J.

citation count

  • 18

complete list of authors

  • Tan, Dawei||Hu, Xin||Cao, Zheng||Luo, Ming||Darensbourg, Donald J

publication date

  • June 2020