Used primarily as a monomer in the synthesis of biodegradable polymers, particularly poly(δ-valerolactone), which has applications in biomedical fields such as drug delivery systems, tissue engineering, and absorbable sutures due to its favorable degradation profile and biocompatibility. Also serves as a solvent and intermediate in organic synthesis, including the production of fragrances, flavors, and fine chemicals. Its ring-opening polymerization allows for the creation of aliphatic polyesters with tunable mechanical and thermal properties, suitable for specialty plastics and coatings.