Ring-opening metathesis polymerization (ROMP) has been another commonly used method to prepare rod–coil block copolymers. For example, a PPV-precursor polymer was synthesized via ROMP of the paracyclophene-based monomers, followed by treatment with NaBu4F and HCl to obtain a PPV-b-PNBE copolymer [78]. Janssen and coworkers described an efficient synthetic route to prepare the high molecular weight P3HT-b-polyethylene (PE) copolymer using ruthenium-catalyzed ROMP [53]. Recently, Hillmyer and coworkers reported the synthetic routes of preparing regioregular poly(3-alkylthiophene)-b-polylactide (P3AT-b-PLA), where the end-functionalized P3AT was used as macroinitiators for the controlled ring-opening polymerization of D,L-lactide [54].