Neat or pristine PLA while having good flexibility, biocompatibility and biodegradability,
also has limited thermomechanical properties that lead to limited applications and
inefficiencies in its processing.
Since PLA parts are more commonly produced using heat processing using methods
like injection molding, extrusion or 3D printing amongst others, this often necessitates
compounding to improve its processibility and performance.
Fillers and additives are used widely in PLA to improve its processibility. Particularly
thermal processing. A particular additive or filler can impact more than one property of PLA.
The properties of the final PLA compound or the performance of the final part, is the
combined effect of all the components as the conditions of processing.
In most applications PLA is rarely used in its neat form. It is either blended/compounded
with other polymers or with additives and fillers. For example in biomedical application like
tissue engineering, PLA might be blended with a compound like hydroxyapatite serving as a
filler to achieve a material that better mimics bone tissue in terms of mechanical properties
With PLA compounding, you are using either of two options; the conventional
compounding or injection molding compounding. The following sections discuss both methods. The rest of the article delves into the additives and fillers in PLA compounding