PlantSea

Plastic packaging is widely used across consumer goods and industrial supply chains, yet it remains one of the largest sources of persistent waste. Even materials designed to dissolve in water often rely on synthetic polymers that can remain in aquatic environments. As regulatory pressure and sustainability commitments increase, manufacturers are seeking alternative materials that can replicate the functionality of plastics while reducing environmental impact. PlantSea, founded in 2020 and headquartered in St Asaph, Wales, develops biomaterials derived from seaweed designed to replace certain single-use plastics and synthetic water-soluble films. By combining marine biomass processing with material engineering, the company explores packaging solutions that dissolve in water or biodegrade naturally. The approach positions seaweed-derived polymers as alternatives to petroleum-based materials commonly used in packaging and consumer products.

Technology and Product

Across several industries, water-soluble films are widely used for packaging applications such as detergent capsules and portioned consumer goods. PlantSea develops biomaterials derived from sustainably sourced seaweed that can be processed into flexible films designed to dissolve in water after use. The materials aim to provide the strength and barrier properties required for packaging while avoiding synthetic polymers commonly used in water-soluble plastics. Seaweed naturally contains polysaccharides that can be processed into film-forming materials. PlantSea’s development work focuses on refining these marine biomolecules into stable materials suitable for industrial processing and packaging applications.

Seaweed biomass used as a raw material for biodegradable packaging materials. (© PlantSea)

Industrial Fit and Applications

The packaging sector is under increasing pressure to reduce plastic waste while maintaining product protection and supply-chain efficiency. PlantSea positions its materials for applications where flexible plastic films are widely used but difficult to recycle. Potential applications include water-soluble packaging for household products, biodegradable films for consumer goods, and materials used within paper-based packaging systems designed to reduce plastic content. Seaweed-derived films may also support emerging packaging formats designed to dissolve during use. By focusing on materials compatible with existing packaging processes, the company aims to support manufacturers seeking alternatives to conventional plastics.

Seaweed-derived packaging materials developed by PlantSea as alternatives to conventional plastic films. (© PlantSea)

Founding Team

PlantSea was founded by Rhiannon Rees, Alex Newnes, and Gianmarco Sanfratello. The company emerged from research exploring the potential of seaweed as a raw material for biodegradable packaging. The founding team combines experience in entrepreneurship, environmental science, and materials innovation.