Guiding the design of oxygen-tolerant and cascade syntheses of block copolymers in a metalloporphyrin-functionalized membrane reactor

Abstract

Industrialized membrane technology holds the promise to push the polymer syntheses into a more efficiently, economically and environmentally benign mode, while reserving the merits of photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization technique such as low-energy input, ppm-level catalyst dosages, mild reaction conditions and high polymerization yields. In this contribution, the polydopamine preactivated membranes as supporting materials were employed for the immobilization of metalloporphyrin-based copolymers to prepare heterogeneous membrane reactors. This membrane reactor boosted exquisite temporal control and provided diverse macromolecular materials with tunable molecular weights and narrow molecular weight distributions. In addition, the efficient, economic and environmental benignity of this technique was highlighted through significant simplicity with respect to the elimination of time-consuming deoxygenation and dialysis procedures. The membrane reactor rapidly removed 99% of unfavorable impurities from products in 4 ~ 5 diavolumes. Demonstrations of block copolymerization and catalyst regeneration in a succession of stages further pointed out the robust performance of this composite membrane. Benefiting from the versatility of metalloporphyrin-functionalized membrane reactor, we envisage that well-structured macromolecular buildups could be synthesized through facile upscaling and cascade processing without the need for intermittent purification.