Top UK Innovators Turning Seaweed into Bioplastics

I recently spent a day at the Rethinking Materials Summit in London. The day was packed full of innovative material companies seeking investment and showcasing their work. There were a number of themes coming through during the event, including a push to utilise AI for material development, and some big questions around recycling. One thing that did jump out at me was how many flexible films were being showcased that used seaweed as their main ingredient.

What is seaweed?

Seaweed, a diverse group of marine algae, is abundant and grows in oceans worldwide, from tropical all the way to polar regions. Seaweed thrives in a variety of marine environments, attaching to substrates like rocks and coral, and flourishing in nutrient-rich waters. Seaweed is categorized into three main types: brown algae (Phaeophyceae), red algae (Rhodophyta), and green algae (Chlorophyta). Each type has unique properties and uses. For example, brown seaweeds like kelp (Laminaria) are known for their rapid growth and high iodine content. Red seaweeds such as dulse (Palmaria palmata) are rich in proteins and vitamins. Green seaweeds like sea lettuce (Ulva) are nutrient-dense and are often used in salads. The rapid growth rate and minimal resource requirements of seaweed make it a sustainable choice for biomaterial production, contributing to its potential as a key player in addressing environmental challenges .

Why is seaweed so good for biomaterials and plastic alternatives?

Seaweed is a great resource for creating biomaterials due to its abundant availability, rapid growth rate, and minimal environmental impact. Unlike traditional crops, seaweed does not require fresh water, arable land, or fertilisers to grow. Seaweed contains natural polymers such as alginate, carrageenan, and agar, which are useful for creating biomaterials. Alginate, derived from brown seaweeds, is known for its gel-forming properties and is widely used in food, medical, and industrial applications. Carrageenan, extracted from red seaweeds, is valued for its thickening, gelling, and stabilising capabilities, making it ideal for various commercial uses. Agar, also from red seaweeds, is notable for its ability to form strong gels even at low concentrations. These polymers are biodegradable, compostable, and non-toxic, providing environmentally friendly alternatives to petroleum-based plastics, while also offering functional versatility in manufacturing and packaging.

The challenges of using seaweed in biomaterial production

Using seaweed for biomaterial production presents several challenges despite its potential benefits. One significant challenge is the scalability of seaweed farming and processing. Current seaweed cultivation methods are often labor-intensive and require specific environmental conditions, which can limit large-scale production. Another issue is the variability inherent in natural polymers; the properties of seaweed-based materials can vary depending on the season and location of harvest, affecting consistency and quality. Each batch of seaweed can have different levels of key components like alginate, carrageenan, and agar, meaning adjustments in the processing methods may be needed to maintain product standards. Furthermore, the properties of seaweed-based polymers, such as tensile strength and durability, sometimes fall short compared to conventional plastics. Overcoming these challenges requires investment in research, technology, and importantly public education to shift the expectations of what these materials can do. Bio-plastics will have very different qualities to the oil-based plastics they are aiming to replace.

Flexsea

FlexSea, a London-based company, is one of the companies making waves in the biomaterials industry by developing innovative seaweed-derived bioplastics. Their product line includes biodegradable films, pellets, and polymers designed to replace single-use plastics in both food and non-food applications. What sets FlexSea apart is their commitment to sustainability and efficiency; their production process uses renewable seaweed biomass without the need for strong chemicals or high temperatures, ensuring minimal environmental impact. Their bioplastics are marine and soil biodegradable and home-compostable within 8-12 weeks, offering a viable solution to plastic pollution. The company's dedication to integrating its materials seamlessly with existing manufacturing technologies is crucial and further enhances their appeal. Their products can be used on current industrial printing lines, sealing machines and vertical/horizontal fold-fill-seal lines.

Notpla

Notpla has made significant strides in creating seaweed-based packaging solutions, earning a reputation for their innovative products. Their notable inventions include edible water bubbles, known as Ooho, and seaweed-coated cardboard for food packaging. Notpla's products are fully biodegradable and have been used in various high-profile events, such as the London Marathon and major football matches, to replace conventional plastic packaging. The company's seaweed-based materials are designed to be composted at home, reducing waste and promoting environmental sustainability. Notpla's approach has been recognized globally, solidifying their position as a pioneer in the bioplastics industry.

Kelpi

Kelpi is a pioneering biotech company that focuses on creating sustainable biopolymers from seaweed. Their innovative approach uses the natural properties of seaweed to produce eco-friendly packaging solutions that are compostable, marine-safe, and carbon-negative. The company specialises in developing high-performance packaging products, including bioplastic coatings for paper and cardboard, which provide a water-resistant barrier suitable for food packaging. Kelpi is also working on creating thin films, which are some of the most challenging plastics to recycle, with less than 1% being recycled in the UK. Kelpi partners with leading institutions such as the University of Bath to advance their research and development, ensuring their products meet high-performance standards.