Caprolactone, scientifically identified as ε-Caprolactone and bearing the CAS number 502-44-3, is a vital chemical compound characterized by its colorless oily liquid appearance and a mild ester aroma. Its molecular structure, a seven-membered lactone ring, equips it with a unique combination of stability, reactivity, and solubility, making it a highly versatile chemical for industrial applications. This article aims to provide a comprehensive overview of Caprolactone, detailing its properties, applications, and essential handling guidelines for professionals in the chemical industry.

The physical and chemical properties of Caprolactone are central to its widespread use. With a high assay of 99.5%min, it ensures purity and consistency in downstream products. Typical properties include a low acidity value (≤0.3 mg KOH/g) and minimal water content (≤0.05%), which are critical for maintaining its stability during storage and its reactivity in polymerization processes. Its low viscosity further facilitates ease of handling and incorporation into various formulations. The inherent chemical structure of Caprolactone makes it an excellent monomer for ring-opening polymerization, a process that yields polycaprolactone (PCL). PCL is a biodegradable and biocompatible polyester widely utilized in medical applications, 3D printing, and as a component in advanced coatings and adhesives.

The application spectrum of Caprolactone is broad and impactful. It is a cornerstone in the production of synthetic rubbers, synthetic fibers, and synthetic resins, imparting enhanced properties such as improved flexibility, durability, and processability. In the medical field, Caprolactone is indispensable for creating PCL-based materials, which are employed in drug delivery systems, tissue engineering scaffolds, and biodegradable medical devices due to their excellent biocompatibility and controlled degradation rates. Its utility extends to enhancing the performance of UV coatings, where it contributes to improved gloss and weather resistance, and it serves as a key component in various adhesive formulations. The compound’s role in creating materials suitable for 3D printing highlights its relevance in modern manufacturing and prototyping.

Proper storage and handling of Caprolactone are paramount to maintaining its quality and ensuring safety. To prevent unwanted polymerization or gelling, it is recommended to store Caprolactone in sealed containers in a dry, well-ventilated environment, protected from heat and direct light. Adherence to recommended storage temperatures, typically below 30°C, ensures its stability for up to 6 months under appropriate conditions. Understanding these properties and handling guidelines is crucial for industrial users to effectively harness the full potential of Caprolactone in their product development and manufacturing processes, driving innovation and delivering high-quality materials across diverse industries.