Determining interfacial tension for fluid-fluid-solid environments

Patent metadata

Field	Value
Publication number	US-11243156-B2
Application number	US-202016923180-A
Country	US
Kind code	B2
Filing date	Jul 8, 2020
Priority date	Jul 8, 2020
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

Aspects of the invention include determining, by a first AFM tip, a first snap-off force of a solid surface immersed in a first fluid, determining, by a second AFM tip, a second snap-off force, determining, by a third AFM tip, a third snap-off force, determining, by the first AFM tip, a fourth snap-off force of a droplet of the first fluid immersed in the second fluid on the solid surface, determining, by the second AFM tip, a fifth snap-off force, determining, by the third AFM tip, a sixth snap-off force, determining a first capillary force for first AFM tip and first droplet based on first snap-off force and fourth snap-off force, determining a second capillary force for second AFM tip and first droplet and a third capillary force for third AFM tip and first droplet, and determining interfacial tension between first fluid and second fluid based on the capillary forces.

First claim

What is claimed is:

1. A computer-implemented method comprising:
using a processor to control an atomic force microscope (AFM) to make determinations;
wherein the AFM comprises:
a first AFM tip having a first radius;
a second AFM tip having a second radius; and
a third AFM tip having a third radius; and

wherein the determinations include:
determining, by the processor operating the first AFM tip, a first snap-off force of a solid surface immersed in a first fluid;
determining, by the processor operating the second AFM tip, a second snap-off force of the solid surface immersed in the first fluid;
determining, by the processor operating the third AFM tip, a third snap-off force of the solid surface immersed in the first fluid;
determining, by the processor operating the first AFM tip, a fourth snap-off force of a first droplet of the first fluid deposited on the solid surface, wherein the first droplet, the first AFM tip, and the solid surface are immersed in a second fluid;
determining, by the processor operating the second AFM tip, a fifth snap-off force of the first droplet of the first fluid deposited on the solid surface, wherein the first droplet, the second AFM tip, and the solid surface are immersed in the second fluid;
determining, by the processor operating the third AFM tip, a sixth snap-off force of the first droplet of the first fluid deposited on the solid surface, wherein the first droplet, the third AFM tip, and the solid surface are immersed in the second fluid;
determining, by the processor, a first capillary force for the first AFM tip and the first droplet of the first fluid immersed in the second fluid based on the first snap-off force and the fourth snap-off force;
determining, by the processor, a second capillary force for the second AFM tip and the first droplet of the first fluid immersed in the second fluid based on the second snap-off force and the fifth snap-off force;
determining, by the processor, a third capillary force for the third AFM tip and the first droplet of the first fluid immersed in the second fluid based on the third snap-off force and the sixth snap-off force; and
determining, by the processor, an interfacial tension between the first fluid and the second fluid based at least in part on the first capillary force, the second capillary force, and the third capillary force.

2. The computer-implemented method of claim 1 , wherein:
the second fluid comprises a gas; and
the first fluid comprises a liquid.

3. The computer-implemented method of claim 1 , wherein:
determining the first capillary force comprises taking the difference between the first snap-off force and the fourth snap-off force;
determining the second capillary force comprises taking the difference between the second snap-off force and the fifth snap-off force;
determining the third capillary force comprises taking the difference between the third snap-off force and the sixth snap-off force.

4. The computer-implemented method of claim 1 , wherein:
determining the interfacial tension between the first fluid and the second fluid based at least in part on the first capillary force, the second capillary force and the third capillary force comprises:
determining a mathematical expression for the first capillary force, the second capillary force and the third capillary force versus the first radius, the second radius and the third radius;
determining at least one parameter for the first fluid and the second fluid from the mathematical expression; and
calculating the interfacial tension utilizing the at least one parameter.

5. The computer-implemented method of claim 1 , wherein the first AFM tip is attached to a cantilever of the AFM.

6. The computer-implemented method of claim 1 , wherein:
the first AFM tip comprises a first material; and
the solid surface comprises a second material.

7. The computer-implemented method of claim 1 , wherein a size of the first droplet of the first fluid is micrometric or sub-micrometric.

8. A system comprising:
a processing circuit configured to operate an atomic force microscope (AFM), the AFM comprising a first AFM tip having first radius, a second AFM tip having a second radius, and a third AFM tip having a third radius;
wherein the processing circuit is further configured to:
determine, by operation the first AFM tip, a first snap-off force of a solid surface immersed in a first fluid;
determine, by operation of the second AFM tip, a second snap-off force of the solid surface immersed in the first fluid;
determine by operation of the third AFM tip, a third snap-off force of the solid surface immersed in the first fluid;
determine, by operation of the first AFM tip, a fourth snap-off force of a first droplet of the first fluid deposited on the solid surface, wherein the first droplet, the first AFM tip, and the solid surface are immersed in a second fluid;
determine, by operation of the second AFM tip, a fifth snap-off force of the first droplet of the first fluid deposited on the solid surface, wherein the first droplet, the second AFM tip, and the solid surface are immersed in the second fluid;
determine, by operation of the third AFM tip, a sixth snap-off force of the first droplet of the first fluid deposited on the solid surface, wherein the first droplet, the third AFM tip, and the solid surface are immersed in the second fluid;
determine a first capillary force for the first AFM tip radius and the first droplet of the first fluid immersed in the second fluid based on the first snap-off force and the fourth snap-off force;
determine a second capillary force for the second AFM tip radius and the first droplet of the first fluid immersed in the second fluid based on the second snap-off force and the fifth snap-off force;
determining a third capillary force for the third AFM tip radius and the first droplet of the first fluid immersed in the second fluid based on the third snap-off force and the sixth snap-off force; and
determine an interfacial tension between the first fluid and the second fluid based at least in part on the first capillary force, the second capillary force, and the third capillary force.

9. The system of claim 8 , wherein:
the second fluid comprises a gas; and
the first fluid comprises a liquid.

10. The system of claim 8 , wherein:
determining the first capillary force comprises taking the difference between the first snap-off force and the fourth snap-off force;
determining the second capillary force comprises taking the difference between the second snap-off force and the fifth snap-off force; and
determining the third capillary force comprises taking the difference between the third snap-off force and the sixth snap-off force.

11. The system of claim 8 , wherein:
determining the interfacial tension between the first fluid and the second fluid based at least in part on the first capillary force, the second capillary force and the third capillary force comprises:
determining a mathematical expression for the first capillary force, the second capillary force and the third capillary force versus the first radius, the second radius and the third radius;
determining at least one parameter for the first fluid and the second fluid from the mathematical expression; and
calculating the interfacial tension utilizing the at least one parameter.

12. The system of claim 8 , wherein the first AFM tip is attached to a cantilever of the AFM.

13. The system of claim 8 , wherein:
the first AFM tip comprises a first material; and
the solid surface comprises a second material.

14. The system of claim 8 , wherein a size of

Assignees

• IBM

Inventors

• Engel Michael
• Viana Ferreira Filipe
• Neumann Barros Ferreira Rodrigo
• Giro Ronaldo
• Steiner Mathias

Classifications

• G01Q30/04

  Display or data processing devices · CPC title

• G01N2013/0208

  by measuring contact angle · CPC title

• G01N13/02 Primary

  Investigating surface tension of liquids · CPC title

• G01Q60/28

  Adhesion force microscopy · CPC title