Greening packaging: a step towards biopolymers in multilayer films

Synthetic polymers, both in monolayer and multilayer forms, have been widely utilized in the packaging industry for several decades. However, they have faced significant competition from other biodegradable materials such as paper and paperboard laminates in flexible packaging applications. The inherent structure of synthetic polymers affords them various properties such as flexibility, strong barrier capabilities, and favourable physical and optical characteristics. Moreover, they often prove to be economically advantageous given prevailing market prices.

With the escalating challenges of solid waste management and the diminishing reserves of natural fossil fuels, which serve as the raw materials for synthetic polymer production, there has been growing interest in biopolymers as an eco-friendly alternative for packaging materials. However, biopolymers must demonstrate comparable barrier properties to synthetic polymers, particularly concerning oxygen and moisture transmission rates. While biopolymers, like paper, offer biodegradability advantages, paper typically lacks the requisite strength and exhibits poor barrier properties.

Various formulations have been explored, incorporating different biopolymers through grafting and blending techniques, aimed at enhancing overall performance. This paper investigates the theoretical foundations supporting the future potential of biopolymers in packaging, explaining their types and the intricate relationship between their structures and properties as a greener alternative.