Evaluation of the Suitability of Poly(Lactide)/Poly(Butylene-Adipate-co-Terephthalate) Blown Films for Chilled and Frozen Food Packaging Applications

Abstract

The use of biopolymers can reduce the environmental impact generated by plastic materials. Among biopolymers, blends made of poly(lactide) (PLA) and poly(butylene-adipate-co-terephthalate) (PBAT) prove to have adequate performances for food packaging applications. Therefore, the present work deals with the production and the characterization of blown films based on PLA and PBAT blends in a wide range of compositions, in order to evaluate their suitability as chilled and frozen food packaging materials, thus extending their range of applications. The blends were fully characterized: they showed the typical two-phase structure, with a morphology varying from fibrillar to globular in accordance with their viscosity ratio. The increase of PBAT content in the blends led to a decrease of the barrier properties to oxygen and water vapor, and to an increase of the toughness of the films. The mechanical properties of the most ductile blends were also evaluated at 4 °C and −25 °C. The decrease in temperature caused an increase of the stiffness and a decrease of the ductility of the films to a different extent, depending upon the blend composition. The blend with 40% of PLA revealed to be a good candidate for chilled food packaging applications, while the blend with a PLA content of 20% revealed to be the best composition as frozen food packaging material.

Synthesis, Characterization and Properties of Biodegradable Poly(Butylene Sebacate-Co-terephthalate)

“…The low T g means that the polymers are in rubber state with possible elastomeric properties at room condition. These polymers, which had low glass transition temperatures, showed very soft properties similar to those of PBAT and poly(ethylene) [ 48 , 49 ].…”

Fracture behavior and mechanical, thermal, and rheological properties of biodegradable films extruded by flat die and calender

“…In particular, the glass transition temperature (T g ) corresponds to the transition temperature between glassy brittle behavior and ductile behavior. 9 The glass transition temperatures of PLA and PBAT are $60 and − 34 C, respectively. Thus, at ambient temperature, PLA is brittle, whereas PBAT is ductile.…”

Evaluation of Mussel Shells Powder as Reinforcement for PLA-Based Biocomposites

“…To achieve good values of flexibility and ductility, many attempts have been made and with various methodologies [ 20 , 21 , 22 ]. The addition of PBAT to PLA has been widely investigated in literature [ 23 , 24 , 25 ], also in different temperature conditions [ 26 ], and tailored formulations have been developed and tested in our research group for several applications [ 27 ]. In the present work PLA has been blended with a biodegradable elastomer, PBAT, in a weight ratio 3:1, as previously reported by the authors with a small amount of talc [ 28 ].…”