Facile Synthesis of Flexible, Donor–Acceptor Side-Chain Functionalized Copolymers via Ring-Opening Metathesis Polymerization

Abstract

A series of polymers has been synthesized via ring-opening metathesis polymerization of donor–acceptor side-chain functionalized monomers. The backbones of the polymers are based on poly(norbornene)s and/or poly(cyclooctene)s, while the side-chains consist of electron-rich 1,5-dialkoxynaphthalene and electron-deficient 1,2,4,5-benzenetetracarboxylic dianhydride (pyromellitic dianhydride). The monomers were proven to be living which allowed for the generation of controlled homopolymers and block copolymers. Side-chain functionalized alternating poly(norbornene/cyclooctene)s were generated using a Grubbs-type initiator containing an unsymmetrical N-heterocyclic carbene ligand. Using UV–vis spectroscopy, a charge-transfer band was detected in random and alternating copolymer solutions due to intramolecular interactions.