ε-Caprolactone

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Molecular formula: C6H10O2

Molecular weight: 114.1

CAS number: 502-44-3

EINECS number: 207-938-1

Structural formula:

Physical and Chemical Properties

Colorless liquid. Soluble in water, easily hygroscopic. Typical physical properties of ε-caprolactone monomer are shown in Table 5-12.

Characteristics and Uses

ε-Caprolactone is a low-viscosity, highly reactive liquid that can be ring-opened by active hydrogen compounds. It is generally used in the manufacture of polycaprolactone polyols, copolymer polyols, and polycaprolactone thermoplastic elastomers. Polycaprolactone polyols are used to produce polyurethane coatings and polyurethane elastomers with excellent hydrolysis resistance and flexibility.

ε-Caprolactone is also used for the modification of polyamides, PET polyesters, and other polymers, and as a reactive solvent/diluent.

The general storage time should not exceed one year. It should not be stored in plastic containers. Exposure to moisture will cause slow polymerization, resulting in turbidity or precipitation.