The first question is, "What are Liquid Properties?" Are they some kind of underwater real estate?
No, Liquid Properties are Not Underwater Real Estate. Rather, they are the characteristics of flowing substances or fluids. We concentrate on understanding and measuring five of these:
1. Surface Tension
4. Contact Angle
You have experienced each in your daily lives. Here are some examples.
Things we often encounter and rarely examine:
A. What kind of water do you use to wash your hands - hot water with soap, maybe?
B. Is your ketchup the right thickness, and is it hard to get out of the bottle?
C. Why does the door stop squeaking when you put on a few drops of 2-in-1 oil on the hinge?
D. A clean, waxed car has bubbles of water after a rain, how come no bubbles when it was dirty?
E. Have you ever noticed that a liter of wine is lighter than a liter of water?
Each of these experiences is the result of a singular attribute of one of these five liquid properties.
The science connected with each of these examples explains why they behave this way.
One way to think about ketchup is the thicker it is, the more it stands up on the hamburger
What the Bottle Problem and the Squeaky Door Fix Have in Common
When you wax your car, you do this strange thing of lowering the surface energy of the
We hope that these cursory explanations of the nature of liquid characteristics provide a rudimentary understanding of and a curiosity about these five liquid properties: surface tension, consistency, viscosity, contact angle and density.
These snippets demonstrated how liquid properties touch your life. I am sure that many of you will respond with, "OK, but so what? Who cares?"
The examples that follow illustrate where and why measurement and control of liquid properties are important. We hope they answer the question, “Why should I care?”
For soap or detergent manufacturers, surface tension has serious implications. A laundry detergent must effectively remove dirt from clothing. To do this, the detergent must lower the surface tension of the water so it will effectively mix with the stains and foreign matter and wash these away.
The ketchup, mustard or mayonnaise producer has two problems. The first is to measure what I call apparent thickness, or how well it flows, otherwise called consistency. A second problem relates to packaging. If a squeeze bottle is used to dispense the product, viscosity has a dramatic impact on how it flows from the bottle.
The design of liquid processing plants, and the piping systems used to move the fluids around are constrained by viscosity. This is a liquid property that can mean success or not.
Where the cleanliness of a surface is important, as in the production of silicon computers chips, a method is needed to test for cleanliness. The measurement of the contact angle of a water drop on the silicon directly correlates to this important detail.
In the process of producing wine, fermentation changes the amount of sugar present. This alters the density of the wine and correlates to the progress of the wine's development. Density measurement is quick and easy. This is another example of the importance of the liquid characteristic of density.
Now for an example of the development and production of a product that uses measurements of all five liquid properties:
A producer of poster paint must provide for a range of surfaces. Various materials or substrates such as coated paper, plastics, and polymers each react differently with paint.
The contact angle of a paint drop on each surface/substrate will be an indicator of how well the paint works, i.e. will it adhere, or tend to runoff? When you get that part of the formulation correct for a specific substrate, the resulting surface tension measurement, which is independent of the substate, is useful in setting up and controlling the production process for that formulation.
This new product option may also have a different viscosity. Application systems such as spray nozzles may have to be modified for the different viscosity reactions. If it turns out that the density varies, the packaging and coverage specifications may need to be changed.
These are but a few examples of the vast world where liquid characters are important elements in production and application for liquid-based products.
Because each of the liquid properties has a different dynamic, the nature of the equipment used to measure each is singular. The basics of these instrument types are as follows:
There are numerous variations, models and techniques used in each of these instrument types.
The following list of industries that depend on the measurement of one or more of these liquid properties illustrates their importance.
|* Adhesives||* Beverage||* Biomedical||* Building Materials|
|* Chemical||* Construction||* Cosmetic||* Electric Power|
|* Food Production||* Paint & Coatings||* Petroleum||* Pharmaceutical|
I hope this harangue about the importance of liquid properties has been interesting, and has shown that liquid properties are not underwater real estate. Please share it with colleagues you think would enjoy it.
Thanks for your attention.
As flabbergasted as usual about these measurement puzzles,
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