Liquid Transfer for Viscoelastic Solutions
Hrishikesh Pingulkar1, Jorge Peixinho1,2, Olivier Crumeyrolle1
1LOMC, CNRS and Université Le Havre Normandie, Le Havre 76600, France.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 18, 2021
Summary
Liquid transfer between surfaces, crucial for printing, is reduced by higher polymer concentration and viscosity. Capillary bridge shape significantly impacts transfer, with Newtonian and viscoelastic fluids behaving oppositely.
Area of Science:
- Fluid dynamics
- Rheology
- Surface science
Background:
- Liquid transfer between surfaces is vital in technologies like printing.
- Understanding viscoelastic fluid behavior is key to optimizing these processes.
- Capillary bridges formed between surfaces are a model system for studying liquid transfer.
Purpose of the Study:
- To experimentally investigate factors affecting viscoelastic liquid transfer between two parallel disks.
- To analyze the influence of polymer concentration, viscosity, and capillary bridge geometry on liquid transfer.
- To compare the behavior of Newtonian and viscoelastic solutions.
Main Methods:
- Preparation of Newtonian and viscoelastic solutions using polyethylene glycol and polyethylene oxide.
- Experimental investigation of liquid transfer in a uniaxial extensional flow setup.
- Systematic variation of parameters: polymer mass fraction, viscosity, disk diameter, aspect ratio, stretching velocity, and filling fraction.
Main Results:
- Increased polymer mass fraction and solvent viscosity reduce liquid transfer.
- Higher initial and final stretching heights decrease liquid transfer for both fluid types.
- Newtonian and viscoelastic solutions exhibit opposing behaviors concerning liquid transfer as capillary bridge shape changes.
Conclusions:
- Interfacial shape instability and gravitational drainage govern liquid transfer.
- Fluid properties and geometry critically influence the efficiency of liquid transfer.
- The study provides insights into optimizing printing and other related technologies.
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