Facile Synthesis of Helical Rod–Coil Block Polymers by the Combination of ATRP and Pd(II)‐Initiated Isocyanides Polymerizations

Abstract

A bifunctional initiator containing propargyl bromoisobutyrate and alkyne‐Pd(II) (PBB‐Pd(II)) is designed and synthesized. The propargyl bromoisobutyrate unit of PBB‐Pd(II) can initiate the atom transfer radical polymerization (ATRP) of vinyl monomers, while the Pd(II) complex can initiate the polymerization of phenyl isocyanides. Both the ATRP and Pd(II)‐mediated isocyanide polymerization are proceeded in living/controlled manner. Thus, combining the two living polymerizations, a series of well‐defined block copolymers bearing rod poly(phenyl isocyanide)s and coil poly(acrylate) segments can be facilely prepared in high yield with tunable composition, controlled molar masses (Mns), and narrow molar mass distributions (Mw/Mns). What is more, benefiting from this synthetic strategy, well‐defined core cross‐linked star polymers are readily synthesized. Optically active block copolymers and star polymers can be facilely obtained by using chiral isocyanide monomers due to the formation of predominated one‐handed helix. The chiral star polymers show excellent enantioselective recognition ability in enantioselective crystallization of racemic compounds.

One-Pot Synthesis, Circularly Polarized Luminescence, and Controlled Self-Assembly of Janus-Type Miktoarm Star Copolymers

“…In addition, the linear diblock copolymer poly­( 1L 70 - b - 2b 280 ) ( M n = 196 kDa, PDI = 1.19), which possessed similar components to (poly- 1L 10 ) 7 -CD-(poly- 2b 20 ) 14 , was synthesized according to previous literature (Figure S22). The CPL measurement showed that poly­( 1L 70 - b - 2b 280 ) was CPL-active, but its g lum value was only 2.6 × 10 –3 (Figure S23), which was much lower than that of (poly- 1L 10 ) 7 -CD-(poly- 2b 20 ) 14 , indicating that the Janus structure advantaged the CPL performance of copolymers.…”

“…The CAC values for (poly- 1L 20 ) 7 -CD-(poly- 2c 10 ) 14 , (poly- 1L 20 ) 7 -CD-(poly- 2c 20 ) 14 , and (poly- 1L 20 ) 7 -CD-(poly- 2c 40 ) 14 were 21.2, 34.1, and 48.4 mg/L, respectively (Figure S28). Meanwhile, the linear diblock copolymer poly­( 1L 140 - b - 2c 140 ) ( M n = 101 kDa, PDI = 1.22) that had similar components to (poly- 1L 20 ) 7 -CD-(poly- 2c 10 ) 14 was prepared (Figure S29), and its CAC was 36.4 mg/mL (Figure S30), obviously larger than that of (poly- 1L 20 ) 7 -CD-(poly- 2c 10 ) 14 . The transmission electron microscope (TEM) and dynamic light scattering (DLS) results for (poly- 1L 20 ) 7 -CD-(poly- 2c 10 ) 14 , (poly- 1L 20 ) 7 -CD-(poly- 2c 20 ) 14 , and (poly- 1L 20 ) 7 -CD-(poly- 2c 40 ) 14 in aqueous solutions are depicted in Figure .…”