Polycaprolactone is a member of the larger polyester family. PCL is biodegradable (see: What’s the Difference Between Biodegradable and Compostable Filaments?) with a very low melting point of 60°C and a glass transition temperature of around -60°C. PCL is semi-crystalline and because of its low melting temperature is relatively soft at room temperature.
PCL is predominantly used in the manufacture of other polymers due to its ability to impart excellent low temperature toughness and flexibility, as well as good oil, fuel and solvent resistance. PCL is particularly important in the manufacture of polyurethanes like TPU. PCL is also commonly used as an additive for PVC.
PCL filament is commonly used in 3D printing to make rapid prototypes due to its very low temperature. The low melting temperature of PCL has both advantages and disadvantages. The obvious disadvantage is that PCL will deform at temperature easily reached on a hot, sunny day however it can easily be warmed to a consistency where it can be reshaped by hand. This makes PCL ideal for printing products that then need to be modified to have a perfect fit. A good example is printing a rivet that you can fit in a hole then heat slightly and reshape to lock in place.
PCL is usually printed at around 120°C however it may range anywhere between 115°C and 145°C. The low printing temperature of PCL means that it will be easily printed by just about any 3D printer. The problem faced when printing with any soft, flexible filament is that it can buckle when being pushed through the extruder, leading to blockages. To mitigate this, a lower print speed or a flexible specific extruder may be used.
As well as being biodegradable, PCL is also bioresorbable, meaning that it can be broken down by the human body into non-toxic substances. For this reason, PCL is commonly used in medical devices where it is particularly useful for drug delivery and medical scaffolds.
PCL is a fascinatingly unique filament due to its extremely low melting temperature and glass transition temperature as well as its good mechanical properties. Whilst most 3D printing filaments are focused on obtaining better thermal stability, PCL provides some fantastic opportunities for designing and printing innovative products that can be easily reheated and reworked. Here at Filaments.directory you can select the right PCL filament for you using our constantly updated list of suppliers and our comprehensive search tool!