Dispersions of Polypropylene for Nanoplastics Research
BAM prepares new reference materials for a more realistic risk assessment of nanoplastic particles
After World War II, the production of plastic products and packaging has been increasing. As we use and dispose of this plastic, more and more of it ends up in our environment. The plastic decomposes and microplastics are formed. In the meantime, people have become aware of this problem. Released microplastic (1-1000 µm in size) can decompose into even smaller nanoplastic (1-1000 nm in size). Since this is smaller, there is a greater risk of humans and animals ingesting these plastic particles unintentionally. Experiments investigating the ingestion or toxicity of nanoplastics usually use nanospheres consisting of polystyrene (PS) or other types of plastic. Yet these were usually not manufactured primarily for the purpose of nanoplastic research, and they often vary by manufacturer. In addition, these types of plastic make up only a fraction of the plastic produced; most of the plastic consists of polyolefins, which include polypropylene (PP).
The goal of the project was to prepare nanoplastic particles consisting of PP that would provide a more realistic reference material for risk assessments. For this purpose, commercially produced PP granules were used and mechanically stressed, causing them to decompose into micro- and nanoplastics. An aqueous nanoplastic dispersion with a diameter of (180.5 ± 5.8) nm was obtained by filtering off the larger fractions, which is thus in the nanoplastic range. In addition, the preparation of the dispersion is repeatable and therefore well suited for the preparation of reference material with specific properties. Additionally, this dispersion does not contain any other surfactants, which may increase stability but can also falsify test results. The stability comes solely from a negative potential in an aqueous medium, which is caused by the hydrophobic properties of the plastic. The preparation of these nanoplastic dispersions is also possible for other molar masses using the method presented, which suggests that it is thus easy to prepare reference materials that respond to the wishes and needs of users.
Publication:
Aqueous Dispersions of Polypropylene: Toward Reference Materials for Characterizing Nanoplastics
Jana Hildebrandt, Andreas F. Thünemann
Macromolecular Rapid Communications, 2023, Jahrgang 44, Ausgabe 6, Aufsatznummer 2200874, Seiten 1-15
DOI:10.1002/marc.202200874 | PUBLICA
Contact:
Bundesanstalt für Materialforschung und -prüfung (BAM)
Dr. rer. nat. habil. Andreas Thünemann
Head of Division Synthesis and Scattering of Nanostructured Materials
Phone +49 30 8104-1610
Email Andreas.Thuenemann(at)bam.de
Source: BAM Paper of the month, 01 June 2023