Universal Effects of Chirality on the Self-Assembly of Chiral Block Copolymers and Polymers

Here, we aim to investigate the universal effects of chirality on the self-assembly of chiral block copolymers (BCPs*) and polymers. Poly(cyclohexylglycolide) (PCG)-containing BCPs* have been synthesized for self-assembly to give systematic comparisons with polylactide (PLA)-containing BCPs*. Opposite handedness of PCG helical chains in enantiomeric BCPs* were identified by the vibrational circular dichroism (VCD) results of carbonyl group (C=O) stretching due to intramolecular chiral interactions. By taking advantage of intermolecular chiral interactions as evidenced by the VCD results of C-O-C vibration, the self-assembly of the PCG-containing BCP* gave helical phase (H*) with preferential handedness as recognized by electron microscopy tomography, suggesting the chirality effect on BCP self-assembly and the homochiral evolution from molecular to hierarchical scales; the results are in line with theoretical prediction based on chiral orientational self-consistent field theory. For chiral polylactides, twisted lamellae in crystalline banded spherulite with preferred handedness could be formed, reflecting the homochiral evolution in crystallized chiral polylactides.