Introduction: The disposal of plastic waste in the oceans has long been an important area of research in the field of environmental protection. For decades, the marine environment has been affected by the degradation of fossil polymers (the vast majority of plastic products), which accumulate on beaches, oceans and even on Arctic sea ice through the flow of ocean currents. To reverse this situation, bio-based polymer composites have been created. This suitable alternative to fossil resources can meet the growing demand for marine composites.
SeaBioComp
The research into these composites is being carried out by a European project called SeaBioComp. In order to reduce the ecological impact of plastics, the challenge is to create renewable materials that can withstand the harsh marine environment for long periods of time, SeaBioComp has developed a flax-based thermoplastic biocomposite. The project has 3D printed several initial prototypes, including fenders and other structures. Research has shown that polymers and composites made from natural raw materials such as biopolymers and biocomposites are seen as potential alternatives to fossil polymers, but with a lower environmental impact, such as the formation of microplastics.
△A range of SeaBioComp demonstration products for maritime applications. Image courtesy of SeaBioComp.
SeaBioComp has been actively seeking to create a durable bio-based composite material for the marine environment since 2019, with a budget of €4.1 million ($4.2 million), co-funded by the EU's Interreg 2 Seas programme. More than half of the funding comes from the European Regional Development Fund (ERDF), which has already funded other 3D printing-related projects in the region, including Portugal's first robot for high-performance and large-format metal 3D printing. Led by Belgian textile research institute Centexbel, SeaBioComp is also conducting analytical work to assess the long-term durability of its materials in order to reduce the ecological impact on the marine environment.
Biocomposites
Firstly, the project has created a self-reinforced polypropylene cross-ester (PLA) composite that has been made into a variety of non-woven and woven fabrics suitable for compression moulding. Secondly, the team developed a new flax-reinforced PLA or acrylic (PMMA) reinforced composite that can be used for resin infusion, compression moulding and additive manufacturing through the flexible moulding (RIFT) manufacturing process.
After extensive testing of the mechanical properties of various biocomposites developed by SeaBioComp, researchers and experts have concluded that these materials approach and in some cases outperform traditional non-biobased composites, such as Sheet Molding Composites (SMC), which can now be used in marine environments. The new bio-based products have been shown to use the same compression moulding conditions as conventional products, while process cycle times can be shorter.
In addition, the project also aims to create products that help reduce the impact on the marine environment and early research has identified flax as the most suitable natural plant fibre to be used as a reinforcement for biocomposites. Flax absorbs large amounts of carbon dioxide as it grows and cleans the soil through phytoremediation. This method of using plant extracts to remove contaminants reduces their bioavailability in the soil.
To combat global sources of marine pollution, the team at SeaBioComp has combined thermoplastic polymers, natural fibres and 3D printing technology. In addition to fenders and other structures, SeaBioComp uses large-scale additive manufacturing techniques to create other semi-industrial products, including boat pumps and topsides.
3D-printed biocomposites
In 2020, SeaBioComp revealed that it relies on FDM printers from Dutch industrial manufacturer Poly Products to 3D print complex structures from bio-compliant materials.
△SeaBioComp uses a CEAD FDM printer to demonstrate the use of bio-based thermoplastic composites in various maritime applications. Image courtesy of CEAD.
In addition to the ecological benefits of the new material, SeaBioComp sees 3D printing as an eco-efficient manufacturing process. Compared to conventional product manufacturing.
● 3D printing of biopolymers is highly eco-efficient as it does not require moulds and there is little production waste.
● It is compatible with the sustainable materials developed for the project and 3D printed products can be recycled at the end of their useful life.
