Abstract:

This data contains measurements of the force vs. height of a particle as it is lifted from a fluid interface. Images of the shape of the interface accompany the force-distance measurements. The goal is to probe the effects of particle shape and roughness and the effect of other particles at the interface. The data supports this publication: Wei He, Nesrin Senbil, A. D. Dinsmore, "Measured Capillary Forces on Spheres at Particle-Laden Interfaces," Soft Matter 11, 5087-5094 (2015). DOI: 10.1039/C5SM00245A

Suggested Citation:

Dinsmore, Anthony, Wei He, Nesrin Senbil. 2016. Dataset supporting publication 'Measured Capillary Forces on Spheres at Particle-Laden Interfaces'. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7Q52MMX

Publications:

He, W., Şenbil, N., & Dinsmore, A. D. (2015). Measured capillary forces on spheres at particle-laden interfaces. Soft Matter, 11(25), 5087–5094. doi:10.1039/c5sm00245a

Purpose:

The goal of these experiments is to measure the forces needed to pull a spherical particle across the interface between two fluids. This data can derive the work needed (1) to remove a particle from the interface or (2) to bind a particle to the interface. The experiments allowed us to probe the effects of interfacial curvature, particle species, and crowding of the interface by other adsorbed particles.

Data Parameters and Units:

Forces (capillary plus buoyancy) are measured in mN and displacements in mm. The shape of the air-water or oil-water interface is measured using a camera with sub-mm resolution. Fig2b.xlsx: Measured force (mN), displacement (mm), and error of free surface spheres and acrylic 1/8 inch spheres. Theory displacement and force. Fig3a.xlsx: Measured force (mN) and displacement (mm) of target spheres - PDMS-coated glass at free water-silicone oil interface and interface with polystyrene (PS) spheres. Fig3b.xlsx: Measured force (mN) and displacement (mm) of target spheres – PDMS coated glass at free water-air interface and interface with polypropylene (PP) 1/8 inch spheres. Fig3c.xlsx: Measured force (mN) and displacement (mm) of target spheres – PTFE sphere at clean interface silicone oil-water and interface with polystyrene (PS) 5/32 inch spheres. Fig3d.xlsx: Measured force (mN) and displacement (mm) of target spheres – PTFE sphere at free interface water-squaline and interface with polypropylene (PP) 1/8 inch spheres. Fig4.xlsx: Maximum force reduction (mN) and size of hole (mm) in array of free-floating spheres. Fig5_inset.xlsx: Displacement (mm) and contact radius (mm) – PDMS coated glass sphere clean interface water-air and with glass slips. Fig5a.xlsx: Measured force (mN) and displacement (mm) - PDMS coated glass sphere clean interface water-air and with glass slips.

Methods:

We used a calibrated cantilever to measure forces and a digital optical camera to measure particle positions and interface shapes. A translation stage was used to move the particle (mm size) step by step through the interface. Figure 1: Force-displacement measurements. R: sphere radius, Rc: contact radius

Instruments:

principally a Nikon D3200 digital camera. Glass spheres with PDMS coatings were used as the particle and water, silicone oil and squalane were used as the fluids.

Error Analysis:

standard error analysis methods were used. Errors were estimated by repeating measurements.

Provenance and Historical References:

Data were generated at UMass Amherst by Wei He and Anthony Dinsmore and Nesrin Senbil. Wei He email: weih@physics.umass.edu

Individual Files: