Used as a monomer in ring-opening metathesis polymerization (ROMP) to produce specialty polymers with unique mechanical and thermal properties. These polymers are applied in advanced materials, including elastomers, coatings, and biomedical devices. Cyclooctene also serves as a ligand or intermediate in organometallic chemistry and catalysis. Its strained cyclic structure makes it valuable in synthetic organic chemistry for studying reaction mechanisms and developing new synthetic routes.