Effect of composition on permeability, mechanical properties and biodegradation of PBAT/PCL blends films

The aim of this work is to evaluate the effect of poly-ε-caprolactone addition and concentration on the gas permeability, tensile properties and biodegradation of PBAT/PCL blends prepared by extrusion in a bench scale single-screw extruder. The blends were characterized by scanning electron microscopy (SEM), tensile properties, permeability to oxygen (O 2 ) and carbon dioxide (CO 2 ) gas and biodegradation in soil. Our data indicate that PCL addition to poly(butylene adipate-co-terephthalate) (PBAT) increases its permeability to both O 2 and CO 2 . The tensile properties of the blends are sensitive to PCL concentration and, particularly, their modulus is higher than that of PBAT. SEM images did not show changes in PBAT morphology upon PCL incorporation and content. Biodegradation (bio-disintegration) in soil was shown to increase with both the presence and content of PCL in the blends. Incorporation of up to 25% of PCL to PBAT can be suitable to develop materials with high potential of biodegradation with preserved tensile properties. The higher permeability upon blending with PCL can also be useful in applications such as cooking food coated with polymeric films.