CoffeeRings · Understanding the drying behavior of polymer-coated particle dispersions using optical tweezers
Horizon Europe — Marie Skłodowska-Curie Actions
- Duration
- 2022-08-01 → 2024-07-31
- EU contribution
- €222,728
- Participants
- 1
- Scheme
- HORIZON-TMA-MSCA-PF-EF
Lines connect the coordinator with its partners.
Results in brief
Understanding the drying behavior of polymer-coated particle dispersions using optical tweezers
The "coffee ring effect" leads to the concentration of dispersed particles at the edges of a drying droplet, which poses challenges for technologies like coating and ink-jet printing that require uniform particle deposition. Traditional methods to counteract this effect, such as increasing liquid viscosity or inducing Marangoni flows, often involve complex systems and restrict material flexibility. In my initial studies, I found that coating dispersed particles with surface-active polymers can effectively mitigate this effect, resulting in a uniform particle film regardless of the particle type, shape, or solvent used. However, my preliminary data were based on an empirical approach—mixing particles with polymers and observing the drying behavior—which provided limited insights. This approach is insufficient for a fundamental investigation because commercial polymers exhibit a broad molecular weight distribution, and the mechanisms of polymer adsorption onto particle surfaces are not well understood. Consequently, a deeper understanding of how polymer coatings influence drying behavior remains necessary.
Data: CORDIS, © European Union
Project objective
After spilling coffee, a tell-tale circular stain is left by the drying droplet. This universal phenomenon, known as the “coffee ring effect”, is observed independent of the dispersed material. However, for many technological processes (e.g., coating and ink-jet printing) a uniform particle deposition is required and the coffee ring effect is a major drawback. In preliminary work, I found that the coffee ring effect can be avoided by coating the dispersed particles with surface-active polymers, which leads to a homogeneous particle film independent of the dispersed material type, shape and liquid. The aim of the project ""CoffeeRings"" is to provide a fundamental understanding on how the physio-chemical properties of the polymer coating affect the interactions of the particles and the drying behavior of the respective particle dispersion.I will receive hands-on training on optical tweezers by the hosting group to fundamentally determine and systematically quantify the changes induced by the polymer coating throughout all stages of the drying process with single-particle resolution. In WP1, I will synthesize a series of model particles with a defined polymer coating and adjust polymer type, grafting density and chain length. In WP2, I will use optical tweezers to measure their interaction potential in bulk liquid, their adsorption rate to liquid interfaces, and their interaction potential when confined at liquid interfaces, which will mimic the involved interactions within drying dispersion droplets. In WP3, I will investigate the drying behavior of the particle dispersions and combine the macroscopic drying manifestations with the microscopic interactions determined in WP2.The successful realization of this project will improve the compositions of particle–polymer–solvent mixtures to obtain reliable, homogeneous deposits, which will stimulate technological advances coating and ink-jet printing processes.""
Original text from CORDIS.
Participants
- GOETEBORGS UNIVERSITET · GoeteborgCoordinatorSweden
Links
- View on CORDIS
- DOI: 10.3030/101064381
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e510c39cb2&appId=PPGMS
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e5f96f252d&appId=PPGMS
Data: CORDIS, © European Union