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Construction of CO2‐based amphiphilic block copolymers (ABCs) is an efficient method for providing CO2‐based polycarbonates with self‐assembly properties in aqueous media. It is challenging to construct CO2‐based ABCs by one‐step strategies from mixed monomers because hydrophilic blocks, usually composed of polar monomers, have negative effects on the synthesis of polycarbonates. In this work, we report a one‐step method to construct CO2‐based ABCs obtained by simultaneous ring‐opening copolymerization (ROCOP) of CO2/epoxides and reversible addition‐fragmentation chain transfer (RAFT) polymerization of N‐isopropyl acrylamide (NIPAM). A trithiocarbonate/carboxy compound was used as the bifunctional chain transfer agent, and an aluminum porphyrin complex was used as the catalyst for ROCOP, which proved to be efficient in CO2 copolymerization even in the presence of NIPAM with strong polarity. This strategy allows flexible control over the molecular weight (5–16 kg/mol) and the hydrophilic‐hydrophobic balance (HLB 9–18) of the ABCs, and ensures narrow polydispersity Đ (1.1–1.3) of the polymers. The ABCs can further self‐assemble into micelles in water with controllable diameters and reversible phase transformation behavior with temperature changes from 25 to 40 °C. This simple route to CO2‐based ABCs with multiple functions has large potential in biomedical applications. [ABSTRACT FROM AUTHOR]

A series of vanadium(V) aroylhydrazine‐arylolates is employed in ethylene polymerization to produce ultra‐high molecular weight polyethylene (UHMWPE), surprisingly extending to such coupling reactions beyond their common usage in the oxidation of hexanes and alcohols. Activated by either MAO or DMAC, the complexes V1–V3 efficiently catalyze the polymerization of ethylene into UHMWPE, that is, with an activity up to 3.37 × 106 g mol−1 h−1 (60°C) and the polyethylene obtained has a molecular weight around 3 million g mol−1, being the highest molecular weight achieved by a vanadium catalyst so far. More importantly, the significant effects of different cocatalysts are well illustrated; the catalytic system with MAO generally shows lower activity with almost one order in the magnitude than that with DMAC (0.43 vs. 3.37 × 106 g mol−1 h−1), but the polyethylenes with higher molecular weights are obtained by the system with MAO. [ABSTRACT FROM AUTHOR]