Figure 4. The carbonyl and methine region of ¹³C NMR spectra of various PCXCs.

(a) Atactic PCXC; (b) enantiopure isotactic (S)-PCXC; (c) stereocomplexed PCXC prepared by mixing (R)- and (S)-polymers in 1:1 mass ratio; (d) PCXC prepared from rac-1/PPN–DNP mediated CXO/CO₂ copolymerization (Table 1, entry 1).