Diblock dialternating terpolymers by one-step/one-pot highly selective organocatalytic multimonomer polymerization

Abstract

The synthesis of well-defined block copolymers from a mixture of monomers without additional actions (“one-pot/one-step”) is an ideal and industrially valuable method. In addition, the presence of controlled alternating sequences in one or both blocks increases the structural diversity of polymeric materials, but, at the same time, the synthetic difficulty. Here we show that the “one-pot/one-step” ring-opening terpolymerization of a mixture of three monomers (N-sulfonyl aziridines; cyclic anhydrides and epoxides), with tert-butylimino-tris(dimethylamino)phosphorene (t-BuP1) as a catalyst, results in perfect diblock dialternating terpolymers having a sharp junction between the two blocks, with highly-controllable molecular weights and narrow molecular weight distributions (Ð < 1.08). The organocatalyst switches between two distinct polymerization cycles without any external stimulus, showing high monomer selectivity and kinetic control. The proposed mechanism is based on NMR, in-situ FTIR, SEC, MALDI-ToF, reactivity ratios, and kinetics studies.

Synthesis of hyperbranched polyesters via the ring-opening alternating copolymerisation of epoxides with a cyclic anhydride having a carboxyl group

“…Recently, the ring-opening alternating copolymerisation (ROAC) of cyclic anhydrides and epoxides has attracted much attention as a third method to access polyesters following polycondensation and ROP because it affords more advantages than them. [22][23][24][25][26][27][28][29][30][31] Polyesters obtained by ROAC involve two types of monomers in the repeating unit, which allow for the easy construction of polymer libraries with a broad structural diversity. In addition, polyesters with functional side chains can be easily synthesised using epoxides having functional side chains.…”

Lithium achieves sequence selective ring-opening terpolymerisation (ROTERP) of ternary monomer mixtures

“…(ABC) n or (ABAC) n , are unknown. [42][43][44][45][46][47][48] The hypothesis of O/S exchange here led us to discover a new type of polymerisation, sequence selective ring-opening terpolymerisation (ROTERP) that we report in this contribution. ROTERP produces poly(ester-altester-alt-trithiocarbonates), i.e.…”

Self-Switchable Polymerization: A Smart Approach to Sequence-Controlled Degradable Copolymers

“…Recently, Hadjichristidis et al reported a breakthrough finding of N-sulfonyl aziridines (Az)'s control over the copolymerization of epoxides in couple with PA (Figure 12). 112 With the t BuP 1 catalyst, perfect diblock copolymers were produced from a mixture of Az, PA, and epoxide monomers. The first-stage ROCOP of PA/Az proceeded very fast.…”