Bio-polymer are on the rise: a good thing, as they have the advantages of hydro-carbon plastic but are also recyclable. As production increases, so too does the demand for the raw ingredients of bio-plastic. Researchers are now turning to algae, for various reasons.

For a start, algae grow copious amounts of the bio-polymer alginate. This substance is extracted from brown algae, and absorbs water to form a gelatinous gum; the basis of the bio-plastic.

In addition, algae grow around the world, and in a wide range of environments. They are also inedible, meaning that using algae for industrial use doesn’t affect agriculture. By building algae-farms in deserts or underground, valuable space can be used for less hardy crops.

The Sahara Forest Project aims to introduce vegetation into the largest desert in the world. Incorporating algae means that the Sahara may become a huge, sustainable bio-polymer production facility.

Now, researchers are testing a novel idea: using the algae as tiny factories themselves. This means that rather than harvesting alginate from algae, the algae would produce high-quality alginate fibres. These can be used as a raw material for plastics, ropes, panels and more.

Various companies are introducing algae-based fibres. German manufacturer Smartfiber makes a type of insulation material using algae fibres, while the Dutch business Algaecom develops algae production sites. Meanwhile, plastics makers Cereplast have launched a bio-propylene for injection moulding that is 20% algae by mass.

As with seaweed production, residual smell can be a problem. Recent developments have shown that it is possible to remove the smell from certain algae-based bio-plastics, but colouring is still an issue: after processing, the material can only be dyed black or (dark) brown. Recent advances in bioluminescence may help change that.

It is clear that algae have huge advantages for the materials industry. Because algae are incredibly efficient at what they do – basically turn CO2 and water into useful materials – we may be seeing algae-based materials on the increase very soon.

Images via Sahara Forest Project, Algaecom, Cereplast and Smartfiber.