High-Oxygen-Barrier Multilayer Films Based on Polyhydroxyalkanoates and Cellulose Nanocrystals

Abstract

This study reports on the development and characterization of organic recyclable high-oxygen-barrier multilayer films based on different commercial polyhydroxyalkanoate (PHA) materials, including a blend with commercial poly(butylene adipate-co-terephthalate) (PBAT), which contained an inner layer of cellulose nanocrystals (CNCs) and an electrospun hot-tack adhesive layer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) derived from cheese whey (CW). As a result, the full multilayer structures were made from bio-based and/or compostable materials. A characterization of the produced films was carried out in terms of morphological, optical, mechanical, and barrier properties with respect to water vapor, limonene, and oxygen. Results indicate that the multilayer films exhibited a good interlayer adhesion and contact transparency. The stiffness of the multilayers was generally improved upon incorporation of the CNC interlayer, whereas the enhanced elasticity of the blend was reduced to some extent in the multilayer with CNCs, but this was still much higher than for the neat PHAs. In terms of barrier properties, it was found that 1 µm of the CNC interlayer was able to reduce the oxygen permeance between 71% and 86%, while retaining the moisture and aroma barrier of the control materials.

Recent Progress of Biodegradable Polymer Package Materials: Nanotechnology Improving Both Oxygen and Water Vapor Barrier Performance

“…The enhancement of the barrier qualities of cellulose-based films in high-humidity conditions has been the subject of certain research projects. One tactic is the creation of multilayer systems containing hydrophobic polymers, such as PP and PET, as exterior layers that can shield the cellulose layers [ 122 ]. Kim et al [ 123 ] introduced a transparent, water-stable, high-oxygen barrier packaging film made from a combination of succinylated cellulose nanofibers (SCNF) and a fluoropolymer (FP) coating.…”

Application of Biopolymers as Sustainable Cladding Materials: A Review

“…PHB needs modifications to enhance its barrier properties. Customised engineering can improve its barrier performance to satisfy certain application needs [176,177]. PBAT provides effective protection against moisture and UV radiation.…”

Management of Operational Parameters and Novel Spinneret Configurations for the Electrohydrodynamic Processing of Functional Polymers

“…[61,62] Similarly, fully compostable multilayer structures with high-oxygen-barrier properties can be developed by incorporating electrospun mats of biodegradable polyesters and carbohydrates, followed by the application of a thermal post-treatment to promote layer adhesion. [54][55][56] Moreover, this methodology has successfully yielded multilayer systems with active and bioactive properties of interest in, for instance, antimicrobial packaging. [54,57,58]…”