Polycaprolactone is a biodegradable polyester

Polyester

Polyester is a category of polymers which contain the ester functional group in their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene terephthalate...

 with a low melting point

Melting point

The melting point of a solid is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at standard atmospheric pressure...

 of around 60°C and a glass transition temperature of about −60°C. PCL is prepared by ring opening polymerization

Ring-opening polymerization

In polymer chemistry, ring-opening polymerization is a form of chain-growth polymerization, in which the terminal end of a polymer acts as a reactive center, where further cyclic monomers join to form a larger polymer chain through ionic propagation...

 of ε-caprolactone

Caprolactone

ε-Caprolactone or simply caprolactone is a cyclic ester, a member of the lactone family, with a seven-membered ring with the formula 5CO2. This colorless liquid is miscible with most organic solvents...

 using a catalyst such as stannous octoate. Recently a wide range of catalysts for the ring opening polymerization of caprolactone have been reviewed. The most common use of polycaprolactone is in the manufacture of speciality polyurethane

Polyurethane

A polyurethane is any polymer composed of a chain of organic units joined by carbamate links. Polyurethane polymers are formed through step-growth polymerization, by reacting a monomer with another monomer in the presence of a catalyst.Polyurethanes are...

s.