A one-step and metal-free route to triblock quaterpolymers from mixtures of vinyl monomers, epoxides, anhydrides, and racemic lactide (rac-LA) has been described, which bridges three polymerization cycles involving ring-opening copolymerization (ROCOP) of epoxides/anhydrides, ring-opening polymerization (ROP) of rac-LA, and RAFT polymerization of vinyl monomers. Taking advantage of the switchable polymerization between ROCOP and ROP, concurrent chain propagation of ROCOP/RAFT and ROP/RAFT sequentially occurs by using a trithiocarbonate compound with carboxylic group (TTC–COOH) as a versatile chain transfer agent. The multiple-chain transfer effect enables independent and precise control over the molecular weights of the three blocks and ensures narrow distribution of the resultant triblock quaterpolymers (Đ < 1.20). This work demonstrates the possibility to acquire block copolymers with high degree of structural complexities in a single efficient process by combining different block polymerization strategies.

A Et3B/DBU pair with a 2/1 feed ratio allowed for the chemoselective control and kinetic control over terpolymerization of epoxides, anhydrides and rac-lactides, affording unique AzCy(AB)xCyAz pentablock terpolymers in a one-step procedure.

A strategy that uses carbon monoxide (CO) as a molecular trigger to switch the polymerization mechanism of a cobalt Salen complex [salen=(R,R)‐N,N′‐bis(3,5‐di‐tert‐butylsalicylidene)‐1,2‐cyclohexanediamine] from ring‐opening copolymerization (ROCOP) of epoxides/anhydrides to organometallic mediated controlled radical polymerization (OMRP) of acrylates is described. The key phenomenon is a rapid and quantitative insertion of CO into the Co−O bond, allowing for in situ transformation of the ROCOP active species (Salen)CoIII‐OR into the OMRP photoinitiator (Salen)CoIII‐CO2R. The proposed mechanism, which involves CO coordination to (Salen)CoIII‐OR and subsequent intramolecular rearrangement via migratory insertion has been rationalized by DFT calculations. Regulated by both CO and visible light, on‐demand sequence control can be achieved for the one‐pot synthesis of polyester‐b‐polyacrylate diblock copolymers (Đ<1.15).

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Large-area bulk oxidized cellulose nanocrystal (OCNC)/graphene nanocomposites with highly oriented structures were produced through a straightforward, cost-effective large-scale evaporation-induced self-assembly process followed by thermal curing. Well-aligned nano-sized graphene layers were evident and separated by the OCNC planar layers, which facilitate highly interconnected and continuous thermal transport parallel to the alignment. Hence, the laminated graphene-based nanocomposites possess an excellent in-plane thermal conductivity of 25.66 W/m K and a thermal conductivity enhancement (η) of 7235% with only a 4.1 vol % graphene loading. This value is the highest recorded among all laminated composite films with <70 wt % filler content reported to date. Using this design strategy, other large-area aligned composites with other functional nanomaterials, already in large-scale production, can be made for use in a wide range of applications.