Insertion metathesis depolymerization of aromatic disulfide-containing dynamic covalent polymers under weak intensity photoirradiation

Aromatic disulfide bonds become dynamic in a radical process under weak intensity photoirradiation and can undergo metathesis. Aryl disulfide-containing dynamic covalent polyurethanes were prepared by the polyaddition of disulfidecontaining diol and diisocyanate compounds. To determine the dynamic nature of the aryl disulfide-containing polymers, insertion metathesis depolymerization was performed under weak intensity photoirradiation at room temperature. The molecular weights of the dynamic covalent polymers decreased as the irradiation time increased.