Chemistry

Materials science

Scanning electron microscope

Engineering

Composite material

Ductility (Earth science)

Polymer blend

Lactic acid

Organic chemistry

Polymer chemistry

Bacteria

Biology

Crystallinity

Ultimate tensile strength

Creep

Elongation

Phase (matter)

Morphology (biology)

Chemical engineering

Copolymer

Adipate

Polymer

Genetics

Volume fraction

Journal of Polymers and the Environment

This paper examines the effect of the melt viscosities of the two component polymers on the morphology and mechanical properties of a series of biodegradable polymer blends. Melt blended compounds of poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) are prepared and their melt viscosities, thermal properties, crystallinity, mechanical properties and phase morphology are investigated. From the relative melt viscosities of PLA and PBAT in the processing regime used in the study, it is possible to calculate the volume fraction at which a co-continuous phase structure is formed. The predicted value is 19 wt% of PBAT and this value is verified by the results of mechanical properties, where results for elongation-to-break show a dramatic rise from around 10% up to 300% in the composition range between 10 and 20 wt% of PBAT. The co-continuous phase structure is also validated by scanning electron microscopy.

Optimising Ductility of Poly(Lactic Acid)/Poly(Butylene Adipate-co-Terephthalate) Blends Through Co-continuous Phase Morphology