Clear Polyethylene microspheres are often used as:

• - Controlled spherical polymer particles in studies of how plastics move, float, settle, filter, separate, adhere, or accumulate in water, air, soil, devices, filters, and test systems, in microplastic transport, detachment, settling, and environmental movement studies where PE composition, spherical shape, and low density are controlled variables.
• - Defined spherical polyethylene challenge particles for filtration, separation, retention, recovery, and removal-efficiency testing.
• - Defined-shape spherical polymer particles for environmental fate studies involving adhesion, biofouling, adsorption, plant contact, and microplastic behavior.
• - Defined-shape spherical polymer particles allowing researchers to isolate the effect of particle shape on plant interaction, adsorption, aging, and biofilm formation and to compare against irregular plastic fragments, films, fibers, or environmental particles.

In general, CPMS clear polyethylene microspheres are selected when the particle must behave as polyethylene: low-density, hydrophobic, non-glass, non-ceramic, non-metallic, and visually unobtrusive. They are used as target size and defined shape polymer particles for filter and screen challenge testing, device passage/blockage studies, floating and settling experiments, formulation trials, and coating or surface-effect development where spherical PE particles are required.

Material: Polyethylene (LDPE)
Color: Translucent
Shape: Spherical
Form: Dry powder
Size Range: Each product code specifies size range (min size - max size)
Density: 0.96g/cc-0.98g/cc, each product code specifies density
Particles in Size Range: > 90%
Spherical Particles: > 90%
Auto-Ignition Temperature: 330C-410C
Index of Refraction: ~1.5
Good resistance to alcohols, dilute alkalis and acids
Limited resistance to aliphatic and aromatic hydrocarbons, mineral oils, oxidizing agents and halogenated hydrocarbons
High temperatures reduce resistance to solvents
Hydrophobic
Might soften and/or melt at temperatures above 100C
Susceptible to stress cracking, if high pressure is applied

Material Safety Data Sheet - Polyethylene Spheres, Beads, Microspheres, and Nanospheres

Some examples of applications utilizing clear polyethylene microspheres:

• Bondline spacers and gap-control particles
• Sacrificial pore formers for porous ceramics and porous polymer structures
• Porosity control in artificial bone scaffolds and tissue-engineering research
• Unpigmented particles of known size for physical simulations and process modeling
• Low-density polymer particles for floating, settling, suspension, and separation studies
• Filter, screen, membrane, and channel challenge testing
• Particle passage, blockage, retention, and recovery studies
• Device, tubing, nozzle, valve, and flow-path testing
• Coating, adhesive, resin, and polymer formulation trials
• Surface texture, slip, matting, or haptic-effect studies in coatings and films
• Controlled polyethylene particles for microplastics research
• Microplastic effects on living organisms
• Microplastics and nanoplastics method development, recovery, and detection studies

Below is just a small sample of articles that have been published referencing Cospheric CPMS spheres and microspheres:

Nardella, F., Brits, M., van Velzen, M.J. et al. Advancing pyrolysis-gas chromatography-mass spectrometry for the accurate quantification of micro- and nanoplastics in human blood. Micropl.&Nanopl. 5, 48 (2025). https://doi.org/10.1186/s43591-025-00152-7

Ewa Babkiewicz, Julita Nowakowska, Marcin L. Zebrowski, Selvaraj Kunijappan, Katarzyna Jarosińska, Rafał Maciaszek, Jacek Zebrowski, Krzysztof Jurek, and Piotr MaszczykMicroplastic Passage through the Fish and Crayfish Digestive Tract Alters Particle Surface Properties, Environmental Science & Technology, 2025, 59 (11), 5693-5703 DOI: https://pubs.acs.org/doi/full/10.1021/acs.est.4c08909.

Wilco Nijenhuis, Kas J. Houthuijs, Marthinus Brits, Martin J.M. van Velzen, Sicco H. Brandsma, Marja H. Lamoree, Frederic M. Béen,
Improved multivariate quantification of plastic particles in human blood using non-targeted pyrolysis GC-MS, Journal of Hazardous Materials, Volume 489, 2025, 137584, ISSN 0304-3894, https://doi.org/10.1016/j.jhazmat.2025.137584.

J. R. Bissonnette, N. E. Harvey, M. L. Rowsell, S. Kiefte, K. J. Houthuijs, F. M. Béen, M. H. Lamoree, L. S. Cahill, K. J. Jobst, Identification of micro-/nanoplastics in human placental blood using comprehensive multidimensional pyrolysis - gas chromatography x ion mobility mass spectrometry, Analytica Chimica Acta, Volume 1376, 2025, 344606, ISSN 0003-2670, https://doi.org/10.1016/j.aca.2025.344606

Q. Wang, P. Kong, Q. Wang, et al., “Polyethylene Microplastic Exposure Disrupts Sex and Gut Hormones via Gut Microbial and Metabolic Pathways,” The FASEB Journal40, no. 6 (2026): e71632, https://doi.org/10.1096/fj.202502063R.

Nicholas V Letwin, Naomi S Varnovitski, Juliska Princz, Gladys L Stephenson, Ryan S Prosser, Toxicity and behavioral responses of environmentally relevant microplastics in earthworms (Eisenia fetida): Ingestion, survival, reproduction, and avoidance across common polymer types, Environmental Toxicology and Chemistry, 2026;, vgag141, https://doi.org/10.1093/etojnl/vgag141

Uroosa and Piwosz K (2026) Systematic optimization of Nile Red staining parameters for the reliable detection of microplastics ≤ 2 µm. Front. Mar. Sci. 13:1818345. https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2026.1818345/full

Born, P., Holldack, K. & Sperl, M. Particle characterization using THz spectroscopy. Granular Matter 17, 2015, 531–536. https://doi.org/10.1007/s10035-015-0578-9

Takaki, K., Rinaldi, G., Berriman, M., Pagán, A, Ramakrishnan, L. Schistosoma mansoni eggs modulate the timing of granuloma formation to promote transmission. bioRxiv 2020.04.14.  https://doi.org/10.1101/2020.0...

L. X. Xu, M. S. Bhamla. Biophysical mechanism of ultrafast helical twisting contraction in the giant unicellular ciliate Spirostomum ambiguum. bioRxiv 854836; https://doi.org/10.1101/854836

Kim, SJ., Kim, JH., The interaction of colloidal particles with weak homeotropic anchoring energy in homogeneous nematic liquid crystal cells. Soft Matter, 2014,10, 2664-2670 https://doi.org/10.1039/C3SM53092B