Table 1 Synthesis, molecular weight, and thermal properties of the pentablock quintopolymer (pentablock-1a) and the corresponding precursors^a

^aThe polymerization was performed using PE-OH as macroinitiator at 80 °C in toluene via ^tBuP₄/DPP/Sn(Oct)₂ catalyst switch strategy. The targeting molecular weight for each block is 1.5 kg mol⁻¹, 15.0 kg mol⁻¹, 15.0 kg mol⁻¹, 30.0 kg mol⁻¹, and 7.0 kg mol⁻¹, respectively.
^bReaction time for the last block.
^cConversion of the last block, determined by ¹H NMR at 60 °C (600 MHz, toluene-d₈), except for the PGA block, where a mixture of toluene-d₈/HFIP-d₂ (~7/3 v/v) was used.
^dDetermined by ¹H NMR of the purified sample at 60 °C (600 MHz, toluene-d₈), except for the PGA block, where a mixture of toluene-d₈/HFIP-d₂ (~7/3 v/v) was used.
^eTotal M_n,NMR at each stage.
^fDetermined by SEC (polystyrene standards) in THF at 50 °C.
^gT_m and T_c were determined by DSC (10 °C min^-1 for heating and cooling, under N₂ atmosphere).
^hPrepared by polyhomologation of sulfoxonium methylene in toluene at 80 °C.

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