In recent years, there has been a growing awareness as to impact of microplastics on our environmental surroundings. Although steps are being taken to minimise these toxic materials, e.g. the banning of microplastics in cosmetics, there are still numerous sources in everyday life like clothes washing and car tyre wear. MICROPLASTIX II project uses modified nanocellulose films as a cheap and sustainable method to remove microplastics from the environment. The entrapment of particles from aqueous dispersion is a result of the high hygroscopicity and large active surface area of the nanocellulose network, which induces capillary forces to trap floating microplastics within the nanocellulose porous structure. Once inside the network, favorable surface interactions enhance the attraction between the particles and the surface of the material leading to efficient capturing. The aim is to improve these films to develop products that can be easily utilised to reduce microplastics flow into ecosystems.
We have observed that capillary forces introduced by the hygroscopic nature of cellulose nanomaterials are strong enough to attract especially nano- and microsized colloidal plastic particles invisible to the naked eye.
The amphiphilic nature of nanocellulose materials plays a role in cohesion between cellulose nanomaterials and plastic particles. On the other hand, charge does not play a major role in capturing small colloidal/nanosized particles but has a major role in capturing larger microplastic particles.
We have shown that nanocellulose networks can be harnessed to capture and quantify even the most challenging fraction of the colloidal plastics (Nature Communications, 2022)
Publications and exhibitions (see also links below the news item)
Leppänen, I., Inherent and Tailored Properties of Cellulose - A Versatile Toolbox for Materials Engineering, Aalto University publication series DOCTORAL THESES, 96/2023, http://urn.fi/URN:ISBN:978-952-64-1323-5
Leppänen, I., Lappalainen, T., Lohtander, T., Jonkergouw, C., Arola, S., and Tammelin, T. Capturing colloidal nano- and microplastics with plant-based nanocellulose networks. Nat Commun, 13, 1814, 2022. https://doi.org/10.1038/s41467-022-29446-7
"Capturing microplastics and pharmaceuticals from waste water" at Helsinki Design Week, Designs for a Cooler Planet exhibition, 2020. https://www.aalto.fi/en/events/capturing-microplastics-and-pharmaceuticals-from-waste-water