PolyCaproLactone (PCL)

Polycaprolactone (PCL) is an organic, biodegradable polyester produced through the ring-opening polymerization (ROP) of the monomer ε-caprolactone.

Structure of Polycaprolactone (PCL)

The chemical formula of its repeating unit is:
(C₆H₁₀O₂)ₙ

PCL has a semi-crystalline chain structure with flexible polymer chains and a relatively low melting temperature (around 60°C), allowing it to be easily blended with other polymers and reinforcing materials.

Properties of Polycaprolactone

• Low melting temperature: approximately 58–63°C

• Glass transition temperature (Tg): around –60°C

• Excellent processability: suitable for injection molding, extrusion, and 3D printing

• Biodegradability: decomposes under environmental or industrial composting conditions

• Biocompatibility: suitable for medical and pharmaceutical applications

• High flexibility: retains elasticity even at low temperatures

Applications of Polycaprolactone

• Medical and pharmaceutical uses: absorbable sutures, drug delivery systems, tissue engineering scaffolds

• 3D printing and rapid prototyping: due to its low melting temperature and precise printability

• Biodegradable products: compostable bags, packaging, and films

• Polymer blending: used as an additive to improve flexibility or lower the melting point of other polymers such as PLA

Advantages of Polycaprolactone

• Biodegradable and environmentally friendly

• Flexible even at low temperatures

• Excellent compatibility with other polymers

• Non-toxic and safe for medical applications

• Good dimensional stability during processing

Disadvantages of Polycaprolactone

• Relatively high production cost compared to common polymers

• Low melting temperature, making it unsuitable for high-temperature applications

• Slow degradation rate under natural conditions (without industrial composting)

• Lower mechanical strength compared to some thermoplastics such as PET or ABS