Creating compostable packaging foams from seaweed

In 2019, 353 million tonnes (Mt) of plastic waste were generated globally, from which 235 Mt came from products with a lifespan under five years¹. Packaging was the greatest source of plastic waste, with around 141 Mt, from which about 47 Mt leaked from collection systems and polluted the environment². Plastic foams are one of the most widely used packaging materials for delivering fragile and perishable products due to their excellent properties (e.g. low-density, low thermal conductivity, excellent cushioning properties and low cost). However, they are mainly made from fossil fuel-derived materials that, although recyclable in principle, recycling is not their usual end-of-life option due to the numerous challenges in our current waste management system.

Algae (seaweed), as a renewable resource, presents an ideal solution offering a pathway to reduce reliance on fossil fuels without competing with food production for land and water resources. Developing compostable foams from algae addresses the environmental impact of plastic pollution and supports sustainable production and consumption patterns, making it a vital step towards a greener, more sustainable future.

CORAL is a UKRI-funded Marie Curie Fellowship Project that aims to develop a family of algae-based and compostable foams as a sustainable alternative for plastic packaging and investigate their applicability and acceptability within the waste management system to identify strategies for their successful implementation. To reach this aim, the project focuses on the following objectives:

• To implement algae-based feedstocks to produce hydrogels and films as precursors to manufacture solid foams. Algae presents a multitude of advantages. It grows rapidly, does not compete for arable land or freshwater resources and is cultivated in various environments, including saline and wastewater.
• To develop cost-effective and scalable foam production methods.
• To obtain tailored formulations and processes to produce compostable and biobased alternatives to conventional plastic foams (e.g. EPS, Expanded Polystyrene; EPE, Expanded Polyethylene; and EPU, Expanded Polyurethane) in bulk size with low densities (10-60 kg/m3), low thermal conductivity (0.033-0.040 W/m⋅K) and bespoke mechanical properties.
• To integrate eco-design in the development of the hydrogels and biofoams with results from LCA, meeting the 'OK Compost Home' certification scheme and industrial-composting according to the EU standard for compostable and biodegradable packaging – EN 13432:2000.
• To explore attitudes towards the biofoams developed and bioplastics in general from a broad stakeholder perspective to understand the challenges associated with their implementation and end-of-life and propose actions to influence policy, labelling and community engagement.

The project's ultimate goal is to mitigate the environmental impact of packaging waste by offering a sustainable alternative that is biobased and compostable. By aligning our research with strategic European and international sustainability goals, including the European Green Deal and the Sustainable Development Goals, we are committed to contributing to a circular economy where materials are reused and recycled, reducing waste and promoting sustainable production and consumption patterns.

• Promoting sustainable packaging and reducing plastic pollution. The development of biobased and compostable foams from algae-based as an alternative to conventional plastic packaging materials.
• Raw materials. Algae-based feedstocks can potentially reduce competition for arable land and food crops used in more traditional bioplastics feedstocks.
• Influencing Policy. By exploring stakeholders' challenges and attitudes towards the materials developed and bioplastics, the project can inform policymakers about the need for compostable materials and end-of-life management regulations.
• Consumer awareness and education. Understanding consumer attitudes and behaviours can lead to better consumer education and awareness campaigns.

CORAL findings can be applied to the packaging industry, waste management systems, policy-making and consumer education. Ultimately, CORAL aims to positively contribute to a circular economy by promoting more sustainable and responsible practices in the production, handling and disposal of packaging materials.