Facile Synthesis of α,ω‐Dihydroxy Telechelic Macromonomers From Ethylene and α‐Olefins for Recyclable Alternating Block Copolymers

AA‐type α,ω‐dihydroxy telechelic polyolefins ( t POs) are key macromonomers for the step‐growth construction of circular polyolefin(‐like) materials and, in particular, block‐level sequence‐controlled olefin block copolymers (OBCs), yet a general route to α,ω‐dihydroxy t POs directly from commodity ethylene/α‐olefins has remained inaccessible. Here, a catalyst‐free tandem Zn–B exchange/oxidation enables near‐quantitative conversion of CCTP‐derived poly(ethylene‐ co ‐α‐olefin) polymeryl‐Zn intermediates into AA‐type α,ω‐dihydroxy t POs with >95% difunctional ratios while preserving industrially relevant microstructures and allowing scale‐up to ∼60 g per batch. These t POs and their corresponding diester t POs undergo polycondensation to afford alternating OBCs with controlled block lengths and tunable compositions. An architecture‐controlled comparison with corresponding random analogs further shows that, although the overall composition primarily determines the total crystallinity, the alternating sequence leads to a more homogeneous nanoscale physical network, lower viscoelastic dissipation, more effective strain hardening, and improved cyclic stability with reduced stress relaxation. These results demonstrate that the AA‐type telechelic platform not only expands telechelic polyolefin chemistry but also enables sequence‐programmable polyolefin architectures with distinct and practically meaningful performance advantages, establishing sequence control as a powerful design lever for recyclable multiblock polyolefin materials.